title: Determining the Neutrino Mass Hierarchy with Atmospheric Neutrinos

abstract:
  The possibility to determine the type of neutrino mass hierarchy by studying
atmospheric neutrino oscillations with a detector capable to distinguish
between neutrino and antineutrino events, such as magnetized iron calorimeters,
is considered. We discuss how the ability to distinguish between the neutrino
mass spectrum with normal and inverted hierarchy depends on detector
characteristics like neutrino energy and direction resolutions or charge
miss-identification, and on the systematical uncertainties related to the
atmospheric neutrino fluxes. We show also how the neutrino mass hierarchy
determination depends on the true values of $\theta_{13}$ and $\theta_{23}$, as
well as on the type of the true hierarchy. We find that for $\mu$-like events,
an accurate reconstruction of the energy and direction of the neutrino greatly
improves the sensitivity to the type of neutrino mass spectrum. For
$\sin^22\theta_{13} \cong 0.1$ and a precision of 5% in the reconstruction of
the neutrino energy and $5^\circ$ in the neutrino direction, the type of
neutrino mass hierarchy can be identified at the 2$\sigma$ C.L. with
approximately 200 events. For resolutions of 15% for the neutrino energy and
$15^\circ$ for the neutrino direction roughly one order of magnitude larger
event numbers are required. For a detector capable to distinguish between
$\nu_e$ and $\bar\nu_e$ induced events the requirements on energy and direction
resolutions are, in general, less demanding than for a detector with muon
charge identification.


title: The Transition between Perturbative and Non-Perturbative QCD

abstract:
  We study both polarized and unpolarized proton structure functions in the
kinematical region of large Bjorken x and four-momentum transfer of few GeV^2.
In this region the phenomenon of parton-hadron duality takes place between the
smooth continuation of the deep inelastic scattering curve and the average of
the nucleon resonances. We present results on a perturbative-QCD analysis using
all recent accurate data with the aim of extracting the infrared behavior of
the nucleon structure functions.


title: Percolation and cosmic ray physics above $10^{17}$eV

abstract:
  We argue that the energy dependence of the average position of the shower
maximum, $\bar X_{max}$, and of the number of produced muons, $N_{\mu}$, can be
explained by a change, around $10^{17}$eV, in the energy dependence of the
inelasticity $K$, which decreases with the energy above the string percolation
threshold.


title: New Physics Search in Flavour Physics

abstract:
  With the running B, kaon and neutrino physics experiments, flavour physics
takes centre stage within today's particle physics. We discuss the
opportunities offered by these experiments in our search for new physics beyond
the SM and discuss their complementarity to collider physics.
  We focus on rare B and kaon decays, highlighting specific observables in an
exemplary mode. We also comment on the so-called B --> pi pi and B --> K pi
puzzles. Moreover, we briefly discuss the restrictive role of long-distance
strong interactions and some new tools such as QCD factorization and SCET to
handle them.


title: "Seesawing" away the hierarchy problem

abstract:
  We describe a model for the scalar sector where all interactions occur either
at an ultra-high scale L_U ~ 10^16 - 10^19 GeV or at an intermediate scale
L_I=10^9 - 10^11 GeV. The interaction of physics on these two scales results in
an SU(2) Higgs condensate at the electroweak (EW) scale, L_EW, through a
seesaw-like Higgs mechanism, L_EW ~ (L_I)^2/L_U, while the breaking of the SM
SU(2)XU(1) gauge symmetry occurs at the intermediate scale L_I. The EW scale
is, therefore, not fundamental but is naturally generated in terms of
ultra-high energy phenomena and so the hierarchy problem is alleviated. We show
that our ``seesaw-Higgs'' model predicts the existence of sub-eV neutrino
masses which are generated through a ``two-step'' seesaw mechanism in terms of
the same two ultra-high scales: m_nu ~ (L_I)^4/(L_U)^3 ~ (L_EW)^2/L_U. We also
show that our seesaw Higgs model can be naturally embedded in theories with
tiny extra dimensions of size R ~ 1/L_U ~ 10^{-16} fm, where the seesaw induced
EW scale arises from a violation of a symmetry at a distant brane if there are
7 tiny extra dimensions.


title: Massive neutrinos in a grounds-up approach with quark-lepton similarity

abstract:
  We examine neutrino oscillations in a two Higgs doublet model (2HDM) in which
the second doublet couples only to the third generation right-handed
up-fermions, i.e., to t_R and to N_3 which is the heaviest right-handed
Majorana neutrino. The inherently large tan(beta) of this model can naturally
account for the large top mass and, based on a quark-lepton similarity ansatz,
when embedded into a seesaw mechanism it can also account for the observed
neutrino masses and mixing angles giving a very small theta_13: -0.017 <
theta_13 < 0.021 at 99% CL, and a very restrictive prediction for the
atmospheric mixing angle: 42.9(deg) < theta_atm < 45.2(deg) at 99% CL. The
large value of tan(beta) also sets the mass scale of the heaviest right-handed
Majorana neutrino N_3 and triggers successful leptogenesis through a
CP-asymmetry in the decays of the N_1 (lightest right-handed Majorana) which is
tan^2(beta) enhanced compared to the CP-asymmetry obtained in models for
leptogenesis with one Higgs doublet or in the MSSM. This enhancement allows us
to relax the lower bound on M_{N_1} and consequently also the lower bound on
the reheating temperature of the early universe.


title: Inclusive and Exclusive Compton Processes in Quantum Chromodynamics

abstract:
  In our work, we describe two types of Compton processes. As an example of an
inclusive process, we consider the high-energy photoproduction of massive muon
pairs off the nucleon. We analyze the process in the framework of the QCD
parton model, in which the usual parton distributions emerge as a tool to
describe the nucleon in terms of quark and gluonic degrees of freedom. To study
its exclusive version, a new class of phenomenological functions is required,
namely, generalized parton distributions. They can be considered as a
generalization of the usual parton distributions measured in deeply inelastic
lepton-nucleon scattering. Generalized parton distributions (GPDs) may be
observed in hard exclusive reactions such as deeply virtual Compton scattering.
We develop an extension of this particular process into the weak interaction
sector. We also investigate a possible application of the GPD formalism to
wide-angle real Compton scattering.


title:
Effects of the restoration of U$_A$(1) symmetry on pseudoscalar meson
  observables

abstract:
  We investigate the restoration of chiral SU$(3)\otimes$SU$(3)$ and axial
U$_A$(1) symmetries, at finite temperature and density, in the framework of the
three flavor Nambu-Jona-Lasinio model with anomaly. We implement a temperature
(density) dependence of the anomaly coefficient motivated by lattice results
for the topological susceptibility and we discuss the restoration of symmetries
by analyzing the behavior of the mesonic chiral partners and of the mixing
angles. The results indicate that the axial part of the symmetry is restored
before the possible restoration of the full U(3)$\otimes$U(3) chiral symmetry
can occur.


title:
Nonlinear $k_{\perp}$-factorization: a new paradigm for an in-nucleus
  hard QCD

abstract:
  We review the origin, and salient features, of the breaking of the
conventional linear $k_{\perp}$-factorization for an in-nucleus hard pQCD
processes. A realization of the nonlinear $k_{\perp}$-factorization which
emerges instead is shown to depend on color properties of the underlying pQCD
subprocesses. We discuss the emerging universality classes and extend nonlinear
$k_{\perp}$-factorization to AGK unitarity rules for the excitation of the
target nucleus.


title:
Color Superconductivity and Radius of Quark Star in Extended NJL Model
  by Using the Dimensional Regularization

abstract:
  A radius of a dense star on the color superconducting phase is investigated
in an extended NJL type model with two flavors of quarks. Since the model is
non-renormalizable, the results depend on the regularization procedure. Here we
apply the dimensional regularization and evaluate the radius of a dense star.
Evaluating the TOV equation, we show the relationship between mass and radius
of the dense star in the dimensional regularization.


title: On the Wess-Zumino term in high energy QCD

abstract:
  Recently, Kovner and Lublinsky proposed new small-x QCD evolution equations
valid when the gluon density inside the target is low. The key element of their
construction is the Wess-Zumino term which ensures the non-commutativity of
valence charges. In this paper we clarify the origin and significance of this
term by showing that it can be naturally incorporated in the effective theory
of Color Glass Condensate. We also reexamine the renormalization group
description in the high density (JIMWLK) regime.


title:
Diagrammatic proof of the BCFW recursion relation for gluon amplitudes
  in QCD

abstract:
  We present a proof of the Britto-Cachazo-Feng-Witten tree-level recursion
relation for gluon amplitudes in QCD, based on a direct equivalence between
BCFW decompositions and Feynman diagrams. We demonstrate that this equivalence
can be made explicit when working in a convenient gauge. We exhibit that gauge
invariance and the particular structure of Yang-Mills vertices guarantees the
validity of the BCFW construction.


title: Probing New Physics through mu-e Universality in K->lnu

abstract:
  The recent NA48/2 improvement on R_K=Gamma(K->e nu_e)/Gamma(K->mu nu_mu)
emphasizes the role of K_l2 decays in probing the mu-e universality.
Supersymmetric (SUSY) extensions of the Standard Model can exhibit mu-e
non-universal contributions. Their origin is twofold: those deriving from
lepton flavor conserving couplings are subdominant with respect to those
arising from lepton flavor violating (LFV) sources. We show that mu-e
non-universality in K_l2 is quite effective in constraining relevant regions of
SUSY models with LFV (for instance, supergravities with a see-saw mechanism for
neutrino masses). A comparison with analogous bounds coming from tau LFV decays
proves the relevance of the measurement of R_K to probe LFV in SUSY.


title: Decays of eta and eta-prime within a chiral unitary approach

abstract:
  Various decays of eta and eta-prime are investigated within the framework of
U(3) chiral effective field theory in combination with a relativistic
coupled-channels approach. Final state interactions are included by deriving s-
and p-wave interaction kernels for meson-meson scattering from the chiral
effective Lagrangian and iterating them in a Bethe-Salpeter equation. Very good
agreement with experimental data is achieved.


title: Truncated Schwinger-Dyson Equations and Gauge Covariance in QED3

abstract:
  We study the Landau-Khalatnikov-Fradkin transformations (LKFT) in momentum
space for the dynamically generated mass function in QED3. Starting from the
Landau gauge results in the rainbow approximation, we construct solutions in
other covariant gauges. We confirm that the chiral condensate is gauge
invariant as the structure of the LKFT predicts. We also check that the gauge
dependence of the constituent fermion mass is considerably reduced as compared
to the one obtained directly by solving SDE.


title:
Formation of charmonium states in heavy ion collisions and
  thermalization of charm

abstract:
  We examine the possibility to utilize in-medium charmonium formation in heavy
ion interactions at collider energy as a probe of the properties of the medium.
This is possible because the formation process involves recombination of charm
quarks which imprints a signal on the resulting normalized transverse momentum
distribution containing information about the momentum distribution of the
quarks. We have contrasted the transverse momentum spectra of J/Psi,
characterized by <p_T^2>, which result from the formation process in which the
charm quark distributions are taken at opposite limits with regard to
thermalization in the medium. The first uses charm quark distributions
unchanged from their initial production in a pQCD process, appropriate if their
interaction with the medium is negligible. The second uses charm quark
distributions which are in complete thermal equilibrium with the transversely
expanding medium, appropriate if a very strong interaction between charm quarks
and medium exists. We find that the resulting <p_T^2> of the formed J/Psi
should allow one to differentiate between these extremes, and that this
differentiation is not sensitive to variations in the detailed dynamics of
in-medium formation. We include a comparison of predictions of this model with
preliminary PHENIX measurements, which indicates compatibility with a
substantial fraction of in-medium formation.


title: Chiral condensates from tau decay: a critical reappraisal

abstract:
  The saturation of QCD chiral sum rules is reanalyzed in view of the new and
complete analysis of the ALEPH experimental data on the difference between
vector and axial-vector correlators (V-A). Ordinary finite energy sum rules
(FESR) exhibit poor saturation up to energies below the tau-lepton mass. A
remarkable improvement is achieved by introducing pinched, as well as
minimizing polynomial integral kernels. Both methods are used to determine the
dimension d=6 and d=8 vacuum condensates in the Operator Product Expansion,
with the results: {O}_{6}=-(0.00226 \pm 0.00055) GeV^6, and O_8=-(0.0053 \pm
0.0033) GeV^8 from pinched FESR, and compatible values from the minimizing
polynomial FESR. Some higher dimensional condensates are also determined,
although we argue against extending the analysis beyond dimension d = 8. The
value of the finite remainder of the (V-A) correlator at zero momentum is also
redetermined: \Pi (0)= -4 \bar{L}_{10}=0.02579 \pm 0.00023. The stability and
precision of the predictions are significantly improved compared to earlier
calculations using the old ALEPH data. Finally, the role and limits of
applicability of the Operator Product Expansion in this channel are clarified.


title: Dynamically generated baryon resonances

abstract:
  Identifying a zero-range exchange of vector mesons as the driving force for
the s-wave scattering of pseudo-scalar mesons off the baryon ground states, a
rich spectrum of molecules is formed. We argue that chiral symmetry and
large-$N_c$ considerations determine that part of the interaction which
generates the spectrum. We suggest the existence of strongly bound
crypto-exotic baryons, which contain a charm-anti-charm pair. Such states are
narrow since they can decay only via OZI-violating processes. A narrow nucleon
resonance is found at mass 3.52 GeV. It is a coupled-channel bound state of the
$(\eta_c N), (\bar D \Sigma_c)$ system, which decays dominantly into the
$(\eta' N)$ channel. Furthermore two isospin singlet hyperon states at mass
3.23 GeV and 3.58 GeV are observed as a consequence of coupled-channel
interactions of the $(\bar D_s \Lambda_c), (\bar D \Xi_c)$ and $(\eta_c
\Lambda),(\bar D \Xi_c')$ states. Most striking is the small width of about 1
MeV of the lower state. The upper state may be significantly broader due to a
strong coupling to the $(\eta' \Lambda)$ state. The spectrum of crypto-exotic
charm-zero states is completed with an isospin triplet state at 3.93 GeV and an
isospin doublet state at 3.80 GeV. The dominant decay modes involve again the
$\eta'$ meson.


title: Supersymmetric Contributions to Bs->K+K-

abstract:
  Inspired by the existing calculation of B->piK decays in supersymmetry
(SUSY), we evaluate the dominant SUSY contributions to Bs->K+K-. We show that
the observables of this process can be significantly modified in the presence
of SUSY. In particular, the branching ratio can be increased considerably
compared to the prediction of the standard model (SM). The effect is even more
dramatic for the CP-violating asymmetries A_dir and A_mix. These asymmetries,
expected to be small in the SM (A_dir is predicted to take only positive
values), change drastically with SUSY contributions. The measurement of these
observables can therefore be used to detect the presence of physics beyond the
SM, and put constraints on its parameters.


title:
Soft Gluon Logarithmic Resummation and Hadron Mass Effects in Single
  Hadron Inclusive Production

abstract:
  We define a general scheme for the evolution of fragmentation functions which
resums soft gluon logarithms in a manner consistent with fixed order evolution.
We present an explicit example of our approach in which double logarithms are
resummed using the Double Logarithmic Approximation. We show that this scheme
reproduces the Modified Leading Logarithm Approximation in certain limits, and
find that after using it to fit quark and gluon fragmentation functions to
experimental data,a good description of the data from the largest x values to
the peak region in ln (1/x) is obtained. In addition, we develop a treatment of
hadron mass effects which gives additional improvements at small x.


title:
Reply to Cohen's comment on the rotation--vibration coupling in chiral
  soliton models

abstract:
  In this short note we summarize the main results of our paper
[hep-ph/0510055] and reply to a recent comment [hep-ph/0511174] on that paper.


title: Poincare Semigroup Symmetry as an Emergent Property of Unstable Systems

abstract:
  The notion that elementary systems correspond to irreducible representations
of the Poincare group is the starting point for this paper, which then goes on
to discuss how a semigroup for the time evolution of unstable states and
resonances could emerge from the underlying Poincare symmetry. Important tools
in this analysis are the Clebsch-Gordan coefficients for the Poincare group.


title:
Singlino dominated LSP as CDM candidate in supersymmetric models with an
  extra U(1)

abstract:
  We consider a singlino dominated neutralino in supersymmetric models with an
extra U(1). In case both the $\mu$ term and also the $Z^\prime$ mass are
generated by the vacuum expectation value of the scalar component of the same
singlet chiral superfield, generically the lightest neutralino is not expected
to be dominated by the singlino. However, if the gaugino corresponding to the
extra U(1) is sufficiently heavy, the lightest neutralino can be dominated by
the singlino and still satisfy the constraints resulting from the $Z^\prime$
phenomenology. We assume a supersymmetry breaking scenario in which the extra
U(1) gaugino can be much heavier than other gauginos. In that framework we show
that the singlino dominated lightest neutralino may be a good candidate for
dark matter in a parameter space where various phenomenological constraints are
satisfied.


title:
Limit Temperatures for Meson and Diquark Resonances in a Strongly
  Interacting Quark Matter

abstract:
  We investigate mesons and diquarks as resonant states above chiral critical
temperature $T_c$ in flavor SU(2) Nambu--Jona-Lasinio model. For each kind of
resonance, we solve the pole equation for the resonant mass in the complex
energy plane, and find an ultimate temperature where the pole starts to
disappear. The phase diagram including these limit temperatures in $T-\mu$
plane is obtained. The maximum limit temperature at $\mu=0$ is approximately
two times $T_c$.


title: Gauge Mediation from Emergent Supersymmetry

abstract:
  We explore the possibility of gauge mediation in a paradigm whereby
supersymmetry is posited to be an accidental symmetry of Nature and the
Standard Model fields are composite bound states that emerge from a conformal
field theory. The resultant effective theory can, through sequestering and
conformal dynamics, exhibit most of the properties of low energy supersymmetry
breaking while averting a number of cosmological and astrophysical constraints
of the traditional framework of gauge mediation via dynamical supersymmetry
breaking. Of particular phenomenological interest is that in our scenario, the
gravitino is superheavy, the neutralino LSP is a viable candidate for cold dark
matter and the flavor changing neutral currents are constrained to be, at the
very minimum, only an order of magnitude below current experimental bounds.


title: Revisiting parton evolution and the large-x limit

abstract:
  This remark is part of an ongoing project to simplify the structure of the
multi-loop anomalous dimensions for parton distributions and fragmentation
functions. It answers the call for a "structural explanation" of a "very
suggestive" relation found by Moch, Vermaseren and Vogt in the context of the
x->1 behaviour of three-loop DIS anomalous dimensions. It also highlights
further structure that remains to be fully explained.


title: Gluonic effects in eta- and etaprime-nucleon and nucleus interactions

abstract:
  Gluonic degrees of freedom play an important role in the masses of the eta
and etaprime mesons. We discuss eta- and etaprime-nucleon and nucleus
interactions where this glue may be manifest. Interesting processes being
studied in experiments are etaprime production in proton-nucleon collisions
close to threshold and possible eta-nucleus bound-states.


title: Anomalous dimensions and reggeized gluon states

abstract:
  Solving the BKP equation and comparing with the structure function of hadron
for deep inelastic scattering processes we are able to find a relation between
reggeized N-gluon states and anomalous dimensions of QCD. To this end we
perform analytical continuation of the Reggeon energy and compare exponents of
two different twist-series expansions for the hadron structure function. This
makes possible to calculate the anomalous dimensions and determine the twist
related to them.


title: Penguin-induced Radiative Baryonic B Decays Revisited

abstract:
  Weak radiative baryonic B decays $\bar B\to B_1\bar B_2\gamma$ mediated by
the electromagnetic penguin process $b\to s\gamma$ are re-examined within the
framework of the pole model. The meson pole contribution that has been
neglected before is taken into account in this work. It is found that the
intermediate $K^*$ contribution dominates in the $\Sigma\bar p\gamma$ mode and
is comparable to the baryon pole effect in $\Lambda\bar p\gamma$ and
$\Xi\bar\Lambda\gamma$ modes. The branching ratios for $B^-\to\Lambda\bar
p\gamma$ and $B^-\to\Xi^0\bar\Sigma^-\gamma$ are of order $2.6\times 10^{-6}$
and $6\times 10^{-7}$, respectively. The threshold enhancement effect in the
dibaryon mass spectrum is responsible by the meson pole diagram. We also study
the angular distribution of the baryon in the dibaryon rest frame. The baryon
pole diagrams imply that the antibaryon tends to emerge in the direction of the
photon in the baryon-pair rest frame. The predicted angular asymmetry agrees
with experiment for $B^-\to\Lambda\bar p\gamma$. Measurements of the
correlation of the photon with the baryon allow us to discriminate between
different models for describing the radiative baryonic B decays. For decays
$B\to\Xi\bar\Sigma\gamma$, a large correlation of the photon to the
$\bar\Sigma$ and a broad bump in the dibaryon mass spectrum are predicted.


title: QCD Radiation in the Production of High s-hat Final States

abstract:
  In the production of very heavy final states - high Mandelstam s-hat - extra
QCD radiation can play a significant role. By comparing several different
parton shower approximations to results obtained with fixed-order perturbation
theory, we quantify the degree to which these approaches agree (or disagree),
focussing on initial state radiation above pT = 50 GeV, for top pair production
at the Tevatron and at the LHC, and for SUSY pair production at the LHC.
Special attention is paid to ambiguities associated with the choice of the
maximum value of the ordering variable in parton shower models.


title:
Spin Effects and Amplitude Structure in Vector Meson Photoproduction at
  Small $x$

abstract:
  An analysis of light vector meson photoproduction at small $x$ on the basis
of the generalized parton distribution (GPD) approach is presented. Our results
on the cross section and spin density matrix elements (SDME) are in fair
agreement with DESY experiments. The predicted double spin longitudinal
$A_{LL}$ asymmetry is not small at HERMES energies.


title:
How to Sum Contributions into the Total Charged-Current Neutrino-Nucleon
  Cross Section

abstract:
  The total charged-current (anti)neutrino-nucleon cross section is usually
estimated by the sum of contributions from quasi-elastic scattering (QES),
single-pion production through baryon resonances (RES), and deep inelastic
scattering (DIS) with an appropriate scratching the phase space of the RES and
DIS contributions. However the resulting total cross section is very sensitive
to the value of the cut-off in invariant mass of the final hadron system
produced in RES and DIS. We examine available experimental data on the QES and
total CC cross sections in order to extract the best-fit value for this
cut-off. By using the same data set we attempt to adjust the poorly known
values of the axial mass for QES and RES.

categories: hep-ph hep-ex nucl-ex nucl-th physics.acc-ph


title:
New proposal of numerical modelling of Bose-Einstein correlations:
  Bose-Einstein correlations from "within"

abstract:
  We describe an attempt to numerically model Bose-Einstein correlations (BEC)
from "within", i.e., by using them as the most fundamental ingredient of a
Monte Carlo event generator (MC) rather than considering them as a kind of
(more or less important, depending on the actual situation) "afterburner",
which inevitably changes the original physical content of the MC code used to
model multiparticle production process.


title: Modular inflation and the orthogonal axion as curvaton

abstract:
  We study a particular supersymmetric realization of the Peccei-Quinn symmetry
which provides a suitable candidate for the curvaton field. The class of models
considered also solves the mu problem, while generating the Peccei-Quinn scale
dynamically. The curvaton candidate is a pseudo Nambu-Goldstone boson
corresponding to an angular degree of freedom orthogonal to the axion field.
Its order parameter increases substantially following a phase transition during
inflation. This results in a drastic amplification of the curvaton
perturbations. Consequently, the mechanism is able to accommodate low-scale
inflation with Hubble parameter at the TeV scale. Hence, we investigate modular
inflation using a string axion field as the inflaton with inflation scale
determined by gravity mediated soft supersymmetry breaking. We find that
modular inflation with the orthogonal axion as curvaton can indeed account for
the observations for natural values of the parameters.


title: Quantum treatment of neutrino in background matter

abstract:
  Motivated by the need of elaboration of the quantum theory of the spin light
of neutrino in matter ($SL\nu$), we have studied in more detail the exact
solutions of the Dirac equation for neutrinos moving in the background matter.
These exact neutrino wavefunctions form a basis for a rather powerful method of
investigation of different neutrino processes in matter, which is similar to
the Furry representation of quantum electrodynamics in external fields. Within
this method we also derive the corresponding Dirac equation for an electron
moving in matter and consider the electromagnetic radiation ("spin light of
electron in matter", $SLe$) that can be emitted by the electron in this case.


title:
Dropping rho and A_1 Meson Masses at Chiral Phase Transition in the
  Generalized Hidden Local Symmetry

abstract:
  We study the chiral symmetry restoration using the generalized hidden local
symmetry (GHLS) which incorporates the rho and A_1 mesons as the gauge bosons
of the GHLS and the pion as the Nambu-Goldstone boson consistently with the
chiral symmetry of QCD. We show that a set of parameter relations, which
ensures the first and second Weinberg's sum rules, is invariant under the
renormalization group evolution. Then, we found that the Weinberg's sum rules
together with the matching of the vector and axial-vector current correlators
inevitably leads to {\it the dropping masses of both rho and A_1 mesons} at the
symmetry restoration point, and that the mass ratio as well as the mixing angle
between the pion and A_1 meson flows into one of three fixed points.


title: Probing the 2-3 leptonic mixing at high-energy neutrino telescopes

abstract:
  We discuss the possibility to probe leptonic mixing parameters at high-energy
neutrino telescopes in a model-independent way, using astrophysical neutron and
pion sources. In particular we show how the octant of the 2-3 mixing angle
might be determined independently of prior knowledge of the source, even when
current uncertainties on the other mixing parameters are included. We also
argue that non-trivial neutrino oscillation effects should be taken into
account when using high-energy flavor ratios for astrophysical diagnostics.


title: Collinearity, convergence and cancelling infrared divergences

abstract:
  The Lee-Nauenberg theorem is a fundamental quantum mechanical result which
provides the standard theoretical response to the problem of collinear and
infrared divergences. Its argument, that the divergences due to massless
charged particles can be removed by summing over degenerate states, has been
successfully applied to systems with final state degeneracies such as LEP
processes. If there are massless particles in both the initial and final
states, as will be the case at the LHC, the theorem requires the incorporation
of disconnected diagrams which produce connected interference effects at the
level of the cross-section. However, this aspect of the theory has never been
fully tested in the calculation of a cross-section. We show through explicit
examples that in such cases the theorem introduces a divergent series of
diagrams and hence fails to cancel the infrared divergences. It is also
demonstrated that the widespread practice of treating soft infrared divergences
by the Bloch-Nordsieck method and handling collinear divergences by the
Lee-Nauenberg method is not consistent in such cases.


title: Radiative two-pion decay of the tau lepton

abstract:
  We consider the bremsstrahlung and model-dependent contributions to the
radiative decay $\tau^- \to \pi^-\pi^0\nu_{\tau}\gamma$ in the context of a
meson dominance model. We focus on several observables related to this decay,
including the branching ratio and the photon and di-pion spectra. Particular
attention is paid to the sensitivity of different observables upon the effects
of model-dependent contributions and of the magnetic dipole moment of the
$\rho^-(770)$ vector meson. Important numerical differences are found with
respect to results obtained in the framework of chiral perturbation theory.


title: Phenomenological study of the double radiative decay $B ->K\gamma\gamma$

abstract:
  Using the operator product expansion (OPE) technique, we study the rare
double radiative decay $B\to K \gamma\gamma$ in the Standard Model (SM) and
beyond. We estimate the short-distance (SD) contribution to the decay amplitude
in a region of the phase space which is around the point where all decay
products have energy $\sim m_b/3$ in the rest frame of the $B$-meson. At lowest
order in $1/m_b$, the $B\to K \gamma\gamma$ matrix element is then expressed in
terms of the usual $B\to K$ form factors known from semileptonic rare decays.
The integrated SD branching ratio in the SM in the OPE region turns out to be
$\Delta {\cal{B}}(B \to K \gamma \gamma)_{SM}^{OPE} \simeq 1 \times 10^{-9}$.
We work out the di-photon invariant mass distribution with and without the
resonant background through $B\to K \{\eta_c,\chi_{c0}\}\to K\gamma \gamma$. In
the SM, the resonance contribution is dominant in the region of phase space
where the OPE is valid. On the other hand, the present experimental upper limit
on $B_s \to \tau^+ \tau^-$ decays, leaves considerable room for New Physics
(NP) in the one-particle-irreducible contribution to $B\to K \gamma \gamma$
decays. In this case, we find that the SD $B\to K \gamma \gamma$ branching
ratio can be enhanced by one order of magnitude with respect to its SM value
and the SD contribution can lie outside of the resonance peaks.


title:
Bounding effective parameters in the chiral Lagrangian for excited heavy
  mesons

abstract:
  We use recent experimental data on charmed mesons to constrain three coupling
constants in the effective lagrangian describing the interactions of excited
heavy-light mesons with light pseudoscalar mesons at order $m_Q^{-1}$.
Predictions in the beauty sector are also derived.


title: The Quark-Quark Correlator: Theory and Phenomenology

abstract:
  New properties of the quark correlator are found via equations of motion. As
a first result, approximate relations can be established among the "soft"
functions; one such relation may help in determining the quark transversity in
a nucleon. Secondly, the Q^2 dependence of the T-odd functions is deduced; the
result is compared to unpolarized Drell-Yan data. Lastly, important remarks are
made about the contributions to g_2(x).


title: Chiral Dynamics of Baryons in a Lorentz Covariant Quark Model

abstract:
  We develop a manifestly Lorentz covariant chiral quark model for the study of
baryons as bound states of constituent quarks dressed by a cloud of
pseudoscalar mesons. The approach is based on a non-linear chirally symmetric
Lagrangian, which involves effective degrees of freedom - constituent quarks
and the chiral (pseudoscalar meson) fields. In a first step, this Lagrangian
can be used to perform a dressing of the constituent quarks by a cloud of light
pseudoscalar mesons and other heavy states using the calculational technique of
infrared dimensional regularization of loop diagrams. We calculate the dressed
transition operators with a proper chiral expansion which are relevant for the
interaction of quarks with external fields in the presence of a virtual meson
cloud. In a second step, these dressed operators are used to calculate baryon
matrix elements. Applications are worked out for the masses of the baryon
octet, the meson-nucleon sigma terms, the magnetic moments of the baryon octet,
the nucleon charge radii, the strong vector meson-nucleon couplings and the
full momentum dependence of the electromagnetic form factors of the nucleon.


title: A Note on Fine-Tuning in Mirage Mediation

abstract:
  Recent progress in string theory moduli stabilization has motivated a mixed
modulus-anomaly mediated supersymmetry breaking scenario, also dubbed `mirage
mediation'. This scenario has a number of phenomenologically attractive
features, in particular with respect to the cosmological gravitino/moduli
problem. In this note, we investigate the issues of fine-tuning associated with
obtaining the correct electroweak symmetry breaking scale in the mirage
mediation scenario. We find that, due to lighter gluinos, the fine-tuning is
smaller than that in other mediation mechanisms.


title: Chiral Lagrangian with Heavy Quark-Diquark Symmetry

abstract:
  We construct a chiral Lagrangian for doubly heavy baryons and heavy mesons
that is invariant under heavy quark-diquark symmetry at leading order and
includes the leading O(1/m_Q) symmetry violating operators. The theory is used
to predict the electromagnetic decay width of the J=3/2 member of the ground
state doubly heavy baryon doublet. Numerical estimates are provided for doubly
charm baryons. We also calculate chiral corrections to doubly heavy baryon
masses and strong decay widths of low lying excited doubly heavy baryons.


title: Inclusive NC and CC diffraction

abstract:
  Recent diffractive structure function measurements in deep inelastic
scattering (DIS) by the H1 and ZEUS experiments at HERA are reviewed. In
neutral current (NC) DIS, precise measurements have been made of diffraction,
$ep \to eXY$, the signature of which is a large rapidity gap (LRG) between the
hadronic system $X$ and the proton or one of its low-mass excited states $Y$.
New results on charged current (CC) DIS are also presented. They are identified
in a CC DIS sample by a large rapidity gap, corresponding to a diffractive
process $ep \to \nu XY$ with a $W$ boson exchange. Moreover, within the
framework of QCD hard scattering factorisation in DIS, all these data provide
constraints on the diffractive parton distribution functions of the proton and
predict a large gluon content. For example, the resulting gluon distribution,
extracted from the H1 measurements, carries an integrated fraction of about 70%
of the exchanged momentum. Note that these functions are crucial inputs for the
calculations of diffractive dijet or charm production in DIS. These parton
distribution functions may also be applicable to hadron-hadron scattering
provided that an additional rapidity gap survival probability is taken into
account.


title:
Noncommutativity of Space and Rotation of Polarization of Light in a
  Background Magnetic Field

abstract:
  Recently the PVLAS collaboration has reported the observation of rotation of
polarization of light propagating in a background magnetic field. In this
letter we explore the possibility that such a rotation is a result of
noncommutativity in the background space-time. To explain the reported
polarization rotation within noncommutative QED we need the noncommutativity
parameter $\theta\simeq (30 {\rm GeV})^{-2}$.


title: Calculation of the scattering amplitudes

abstract:
  General equations for the calculation of amplitudes are presented. As an
illustration of application of proposed formulae we calculate electron-electron
scattering amplitudes.


title:
b -> d Penguins: CP Violation, General Lower Bounds on the Branching
  Ratios and Standard Model Tests

abstract:
  With the wealth of new data from the B-factories, b -> d penguin decays
become available for study, in addition to their b -> s counterparts that have
proven an indespensable tool for the exploration of new-physics effects in
flavour physics. A prominent example of the b -> d penguin transitions is $\bar
B^0_d \to K^0 \bar K^0$. We show that this decay can be charaterized in the
Standard Model by a surface in the observable space of the direct and
mixing-induced CP asymmetries and the branching ratio. The form of this
surface, which is theoretically clean, implies a lower bound for the branching
ratio that has recently been confirmed experimentally. If future measurements
of the CP asymmetries yield a point away from the SM surface, this would be an
interesting signal of new physics. We point out that the hadronic parameters in
$\bar B^0_d \to K^0 \bar K^0$ that parameterize the position on the SM surface
are related to hadronic parameters in the B -> pi K system. The fact that the
branching ratio of $\bar B^0_d \to K^0 \bar K^0$ is very close to its lower
bound yields interesting implications for B -> pi K even without knowledge of
the CP asymmetries of $\bar B^0_d \to K^0 \bar K^0$. The mechanism that
produces the lower bound for $\bar B^0_d \to K^0 \bar K^0$ is actually much
more general; we derive lower bounds for various other b -> d penguin-induced
processes, including B -> rho gamma and $B^\pm \to K^{(\ast)\pm} K^{(\ast)}$.
Some of these theoretical lower bounds are very close to the current
experimental upper bounds.


title: Gauge non-invariance of quark-quark interactions

abstract:
  We discuss the gauge invariance of quark-quark potential in QCD in the
perturbative treatment, and show that the gauge dependence of the quark-gluon
interaction cannot be eliminated. Therefore, the quark-quark potential cannot
properly be written in terms of physical variables in the perturbation theory.
This is in contrast to the QED case in which the gauge invariance of the
electron-photon interaction is guaranteed by the current conservation. As an
example, we show that the different choices of the gauge fixing give different
Coulomb interactions when the fermion current is not conserved. Also, we
examine a possible existence of $QG-$state (one quark$-$one gluon)
corresponding to the conserved color current, which should have a fractional
electric charge.


title: Inverted neutrino mass hierarchies from U(1) symmetries

abstract:
  Motivated by effective low energy models of string origin, we discuss the
neutrino masses and mixing within the context of the Minimal Supersymmetric
Standard Model supplemented by a U(1) anomalous family symmetry and additional
Higgs singlet fields charged under this extra U(1). In particular, we interpret
the solar and atmospheric neutrino data assuming that there are only three
left-handed neutrinos which acquire Majorana masses via a lepton number
violating dimension-five operator. We derive the general form of the charged
lepton and neutrino mass matrices when two different pairs of singlet Higgs
fields develop non--zero vacuum expectation values and show how the resulting
neutrino textures are related to approximate lepton flavor symmetries. We
perform a numerical analysis for one particular case and obtain solutions for
masses and mixing angles, consistent with experimental data.


title:
Three-jet event-shapes in lepton-proton scattering at next-to-leading
  order accuracy

abstract:
  We compute the differential distributions of two three-jet event-shape
observables at the next-to-leading order accuracy at fixed values of the DIS
kinematic variables. The observable $\Kout$ measures the out-of-event-plane
momentum. The other observable $y_3$ is the maximum value of the $\ycut$
resolution variable for which an event is classified as three-jet event. We
also show the dependence of the fixed-order predictions on the renormalisation
and factorisation scales. The radiative corrections are in general large and
depend on the value of the DIS kinematic range.


title:
Study of V_LV_L\to t\bar{t} at the ILC Including O(alpha_s) QCD
  Corrections

abstract:
  In the event that the Higgs mass is large or that the electroweak
interactions are strongly interacting at high energy, top quark couplings to
longitudinal components of the weak gauge bosons could offer important clues to
the underlying dynamics. It has been suggested that precision measurements of
W_L W_L \to t\bar{t} and Z_L Z_L \to t\bar{t} might provide hints of new
physics. In this paper we present results for O(alpha_s) QCD corrections to
V_LV_L\to t\bar{t} scattering at the ILC. We find that corrections to cross
sections can be as large as 30% and must be accounted for in any precision
measurement of VV\to t\bar{t}.


title: Dirac and Majorana neutrinos in matter

abstract:
  We consider the matter effects on neutrinos moving in background on the basis
of the corresponding quantum wave equations. Both Dirac and Majorana neutrino
cases are discussed. The effects for Dirac neutrino reflection and trapping as
well as neutrino-antineutrino annihilation and $\nu\overline{\nu}$ pair
creation in matter at the interface between two media with different densities
are considered. The spin light of neutrino in matter is also discussed.


title:
Implications of a very light pseudoscalar boson on lepton flavor
  violation

abstract:
  A long-lived very light pseudoscalar boson would favor lepton flavor
violating transitions of charged leptons. Its implications on the l_i --> l_j
\gamma \gamma, and l_i --> l_j e^+ e^- transitions are investigated. Assuming 2
m_e < m_\phi <m_\mu, it is found that the inequality B(l_i --> l_j \gamma
\gamma)<B(l_i --> l_j e^+ e^-) is hold. The experimental constraints on the
decays l_i --> l_j \gamma, l_i --> l_j l_k l_k, and l_i --> l_j \gamma \gamma
are used to bound the \phi l_i l_j couplings.


title:
Toward High Precision Higgs-Boson Measurements at the International
  Linear e+e- Collider

abstract:
  This report reviews the properties of Higgs bosons in the Standard Model (SM)
and its various extensions. We give an extensive overview about the potential
of the ILC operated at centre-of-mass energies up to 1 TeV (including the gamma
gamma option) for the determination of the Higgs boson properties. This
comprises the measurement of the Higgs boson mass, its couplings to SM fermions
and gauge bosons, and the determination of the spin and the CP quantum numbers
of the Higgs. The extensions of the SM that are analyzed in more detail are
heavy SM-like Higgs bosons, heavy Higgs bosons in the framework of
Supersymmetry (SUSY) and further exotic scenarios. We review recent theoretical
developments in the field of Higgs boson physics. The important question what
the ILC can contribute to Higgs boson physics after the LHC, the LHC/ILC
interplay and synergy is discussed. The impact of Higgs boson physics on
cosmology in several SUSY frameworks is analyzed. The impact of the accelerator
and dector performance on the precision of measurements are discussed in
detail. We propose a strategy to optimize future analyses. Open questions
arising for the various topics are listed, further topics of study and
corresponding roadmaps are suggested.


title: Diffractive parton density functions

abstract:
  We discuss the perturbative QCD description of diffractive deep-inelastic
scattering, and extract diffractive parton distributions from recent HERA data.
The asymptotic collinear factorisation theorem has important modifications in
the sub-asymptotic HERA regime. In addition to the usual resolved Pomeron
contribution, the direct interaction of the Pomeron must also be accounted for.
The diffractive parton distributions are shown to satisfy an inhomogeneous
evolution equation, analogous to the parton distributions of the photon.


title: Shape-Function Effects and Split Matching in B-> Xs l+ l-

abstract:
  We derive the triply differential spectrum for the inclusive rare decay B ->
Xs l+ l- in the shape function region, in which Xs is jet-like with $mX^2
\lesssim mb \Lambda_QCD$. Experimental cuts make this a relevant region. The
perturbative and non-perturbative parts of the matrix elements can be defined
with the Soft-Collinear Effective Theory, which is used to incorporate alphas
corrections consistently. We show that, with a suitable power counting for the
dilepton invariant mass, the same universal jet and shape functions appear as
in B-> Xs gamma and B-> Xu l nu decays. Parts of the usual alphas(m_b)
corrections go into the jet function at a lower scale, and parts go into the
non-perturbative shape function. For B -> Xs l+ l-, the perturbative series in
alphas are of a different character above and below mu=mb. We introduce a
``split matching'' method that allows the series in these regions to be treated
independently.


title: Distinguishing Between Models with Extra Gauge Bosons at the ILC

abstract:
  Extra neutral gauge bosons arise in many extensions of the Standard Model. If
one were to be discovered it would be necessary to measure its properties so
that we could understand its origins. In this report we find that Z' couplings
can be measured at the ILC precisely enough to distinguish between models up to
a Z' mass of 2-3 TeV. An important ingredient in these measurements is
polarization of the e^- and to a lesser extent e^+ beams. b and c-quark tagging
would also give important additional information.


title: A Higher-dimensional Origin of the Inverted Mass Hierarchy for Neutrino

abstract:
  We present successful lepton mass matrices with an inverted mass hierarchy
for neutrinos, which follow from a geometrical structure of a (1+5) dimensional
space-time where two extra dimensions are compactified on the T^2/Z_3 orbifold.
A 5^* and a right-handed neutrino N in each family are localized on each of the
equivalent three fixed points of the orbifold while three 10's and Higgs
doublets H_u and H_d live in the bulk. An S_3 family symmetry is assumed on
three 5^*'s and on three N's, since the three fixed points are equivalent to
one another. The Higgs field \phi responsible for the B-L breaking is localized
on one of the three fixed points, which generates the inverted hierarchy for
the neutrino masses. The baryon asymmetry is well explained in the non-thermal
leptogenesis via inflaton decay. We emphasize that the present model predicts
the effective neutrino mass, <m>_{ee}, responsible for neutrinoless double beta
decays as <m>_{ee}\simeq 50 meV. This will be accessible to future experiments.


title: Effects of density fluctuations on Supernova Neutrinos: 2$\nu$ Case

abstract:
  This paper has been withdrawn due to the use of some incorrect neutrino
parameter space ranges.


title:
Broken Flavor 2 <-> 3 Symmetry and phenomenological approach for
  universal quark and lepton mass matrices

abstract:
  A phenomenological approach for the universal mass matrix model with a broken
flavor 2 <-> 3 symmetry is explored by introducing the 2 <-> 3 antisymmetric
parts of mass matrices for quarks and charged leptons . We present explicit
texture components of the matrices, which are consistent with all the neutrino
oscillation experiments and quark mixing data. The mass matrices have a common
structure for quarks and leptons, while the large lepton mixings and the small
quark mixings are derived with no fine tuning due to the difference of the
phase factors. The model predicts a value, 2.4 x 10^{-3}, for the lepton mixing
matrix element square |U_{13}|^2, and also predict <m_nu>=(0.89-1.4) x 10^{-4}
eV for the averaged neutrino mass which appears in the neutrinoless double beta
decay.


title: Elements of Physics with a Photon Collider

abstract:
  After a brief description of the basic principle of a photon collider, we
summarize the physics potential of such a facility at high energies. Unique
opportunities are provided in supersymmetric theories for the discovery of
heavy scalar and pseudoscalar Higgs bosons as well as selectrons and
e-sneutrinos.


title:
A New Method for Calculating Differential Distributions Directly in
  Mellin Space

abstract:
  We present a new method for the calculation of differential distributions
directly in Mellin space without recourse to the usual momentum-fraction (or
z-) space. The method is completely general and can be applied to any process.
It is based on solving the Integration-by-Parts identities when one of the
powers of the propagators is an abstract number. The method retains the full
dependence on the Mellin variable and can be implemented in any program for
solving the IBP identities based on algebraic elimination, like Laporta.
General features of the method are: 1) faster reduction, 2) smaller number of
master integrals compared to the usual z-space approach and 3) the master
integrals satisfy difference instead of differential equations. This approach
generalizes previous results related to fully inclusive observables like the
recently calculated three-loop space-like anomalous dimensions and coefficient
functions in inclusive DIS to more general processes requiring separate
treatment of the various physical cuts. Many possible applications of this
method exist, the most notable being the direct evaluation of the three-loop
time-like splitting functions in QCD.


title: Solar Neutrinos: Spin Flavour Precession and LMA

abstract:
  The time dependence that appears to be hinted by the data from the first 13
years of the solar neutrino Gallium experiments is viewed as resulting from a
partial conversion of active neutrinos to light sterile ones through the
resonant interaction between the magnetic moment of the neutrino and a varying
solar field. A summary of the model and its predictions are presented for the
forthcoming experiments Borexino and LENS.


title: Colour superconductivity in a strong magnetic field

abstract:
  We explore the effects of an applied strong external magnetic field in a
three flavour massless colour superconductor. The long-range component of the B
field that penetrates the superconductor enhances some quark condensates,
leading to a different condensation pattern. The external field also reduces
the flavour symmetries in the system, and thus it changes drastically the
corresponding low energy physics. Our considerations are relevant for the study
of highly magnetized compact stars.


title:
Role of the singular factors in the standard fits for initial parton
  densities

abstract:
  Total resummation of double- and single- logarithms of x contributing to the
spin-dependent structure function g_1 ensures its steep rise at small $x$. In
the asymptotic limit x ->0, the resummation leads to the Regge behavior of g_1
and allows to calculate the non-singlet and singlet intercepts of g_1. DGLAP
lacks such a resummation but suggests special phenomenological fits for the
initial parton densities such that the singular factors x^{-\alpha} in the fits
mimic the resummation and also provide g_1 with the steep (power-like) rise at
the small-x region. Accounting for the total resummaton of logarithms of x
allows to drop the singular factors in the fits and leads to remarkable
simplifications of the fits.


title: Supersymmetry Parameter Analysis: SPA Convention and Project

abstract:
  High-precision analyses of supersymmetry parameters aim at reconstructing the
fundamental supersymmetric theory and its breaking mechanism. A well defined
theoretical framework is needed when higher-order corrections are included. We
propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a
consistent set of conventions and input parameters. A repository for computer
programs is provided which connect parameters in different schemes and relate
the Lagrangian parameters to physical observables at LHC and high energy e+e-
linear collider experiments, i.e., masses, mixings, decay widths and production
cross sections for supersymmetric particles. In addition, programs for
calculating high-precision low energy observables, the density of cold dark
matter (CDM) in the universe as well as the cross sections for CDM search
experiments are included. The SPA scheme still requires extended efforts on
both the theoretical and experimental side before data can be evaluated in the
future at the level of the desired precision. We take here an initial step of
testing the SPA scheme by applying the techniques involved to a specific
supersymmetry reference point.


title:
Probing neutrino mass hierarchies and $\phi_{13}$ with supernova
  neutrinos

abstract:
  We investigate the feasibility of probing the neutrino mass hierarchy and the
mixing angle $\phi_{13}$ with the neutrino burst from a future supernova. An
inverse power-law density $\rho \sim r^{n} $ with varying $n$ is adopted in the
analysis as the density profile of a typical core-collapse supernova. The
survival probabilities of $\nu_{e}$ and $\bar{\nu}_{e}$ are shown to reduce to
two-dimensional functions of $n$ and $\phi_{13}$. It is found that in the
$n-\sin^{2} \phi_{13}$ parameter space, the 3D plots of the probability
functions exhibit highly non-trivial structures that are sensitive to the mass
hierarchy, the mixing angle $\phi_{13}$, and the value of $n$. The conditions
that lead to observable differences in the 3D plots are established. With the
uncertainty of $n$ considered, a qualitative analysis of the Earth matter
effect is also included.


title: Generalized Distribution Amplitudes at the $Z$ pole

abstract:
  We investigate the exclusive two-pion production at the $Z$-pole through the
process $e^+e^-\to Z \to \pi\pi \gamma$. In the kinematical region where the
invariant mass of the two pions is much smaller than the mass of the $Z$ boson,
the process can be factorized into the convolution of a hard coefficient and a
soft matrix element, the generalized distribution amplitude of two pions. We
calculate the differential cross-section of charged pion pair production and
neutral pion pair production and find the former to be much larger than the
later. We show that combining the measurements of charged pion pair production
and neutral pion pair production at the $Z$-pole provides a convenient approach
to access the $C$-odd part of the $2\pi$ distribution amplitudes.


title:
Unstable particle production near threshold with effective theory
  methods

abstract:
  We illustrate the use of effective theory methods to describe resonant
unstable particles. We outline the necessary ingredients to describe $W$-pair
production close to threshold in $e^-e^+$ collisions.


title: The Electroweak Phase Transition in Models with Gauge-Higgs Unification

abstract:
  The dynamics of five dimensional Wilson line phases at finite temperature is
studied in the one-loop approximation. We show that at temperatures of order
$T\sim 1/L$, where L is the length of the compact space, the gauge symmetry is
always restored and the electroweak phase transition appears to be of first
order.
  We focus on a specific model where the Wilson line phase is identified with
the Higgs field (gauge-Higgs unification). The transition is of first order
even for values of the Higgs mass above the current experimental limit. If
large localized gauge kinetic terms are present, the transition might be strong
enough to give baryogenesis at the electroweak transition.


title: Resummation of event-shapes at hadron-hadron colliders

abstract:
  We point out that a study of event shapes at hadron colliders allows to
explore novel aspects of QCD. These studies are today made easier by the
development of a program which automates the resummation.


title: Semi-numerical evaluation of one-loop corrections

abstract:
  We present a semi-numerical method to compute one-loop corrections to
processes involving many particles. We treat in detail cases with up to five
external legs and massless internal propagators, although the method is more
general.


title: Importance of a Measurement of F_L(x,Q^2) at HERA

abstract:
  I investigate what a direct measurement of the longitudinal structure
function F_L(x,Q^2) could teach us about the structure of the proton and the
best way in which to use perturbative QCD for structure functions. I assume
HERA running at a lowered beam energy for approximately 4-5 months and examine
how well the measurement could distinguish between different theoretical
approaches. I conclude that such a measurement would provide useful information
on how to calculate structure functions and parton distributions at small x.


title: Fermion mass relations in a supersymmetric SO(10) theory

abstract:
  Neutrino and charged fermion masses provide important constraints on grand
unified theories. We illustrate this by focusing on a renormalizable,
supersymmetric SO(10) theory proposed long ago, that recently attracted great
interest in view of its minimality. We show how the nature of the light Higgs,
which depends on the GUT scale fields, gets reflected on the precise
predictions for fermion masses and mixings. We exemplify this on the case of
dominant Type II see-saw, which gets severely constrained and is likely to
fail.


title: Polyakov loop at low and high temperatures

abstract:
  We describe how the coupling of the gluonic Polyakov loop to quarks solves
different inconsistencies in the standard treatment of chiral quark models at
finite temperature at the one quark loop level. Large gauge invariance is
incorporated and an effective theory of quarks and Polyakov loops as basic
degrees of freedom is generated. From this analysis we find a strong
suppression of finite temperature effects in hadronic observables below the
deconfinement phase transition triggered by approximate triality conservation
in a phase where chiral symmetry is spontaneously broken (Polyakov cooling). We
also propose a simple phenomenological model to describe the available lattice
data for the renormalized Polyakov loop in the deconfinement phase. Our
analysis shows that non perturbative contributions driven by dimension-2 gluon
condensates dominate the behaviour of the Polyakov loop in the regime T_c < T <
6T_c.


title:
Quantum black holes and thermalization in relativistic heavy ion
  collisions

abstract:
  A new thermalization scenario for heavy ion collisions is discussed. It is
based on the Hawking--Unruh effect: an observer moving with an acceleration $a$
experiences the influence of a thermal bath with an effective temperature $T =
a / 2\pi$, similar to the one present in the vicinity of a black hole horizon.
In the case of heavy ion collisions, the acceleration is caused by a pulse of
chromo--electric field $E \sim Q_s^2/g$ ($Q_s$ is the saturation scale, and $g$
is the strong coupling), the typical acceleration is $a \sim Q_s$, and the heat
bath temperature is $T \simeq Q_s / 2\pi \sim 200$ MeV. In nuclear collisions
at sufficiently high energies the effect can induce a rapid thermalization over
the time period of $\tau \sim \pi/Q_s $ accompanied by phase transitions. A
specific example of chiral symmetry restoration induced by the chromo--electric
field is considered; it is mathematically analogous to the phase transition
occurring in the vicinity of a black hole.


title:
Nonlocality effects on spin-one pairing patterns in two-flavor color
  superconducting quark matter and compact stars applications

abstract:
  We study the influence of nonlocality in the interaction on two spin one
pairing patterns of two-flavor quark matter: the anisotropic blue color paring
besides the usual two color superconducting matter (2SCb), in which red and
green colors are paired, and the color spin locking phase (CSL). The effect of
nonlocality on the gaps is rather large and the pairings exhibit a strong
dependence on the form factor of the interaction, especially in the low density
region. The application of these small spin-one condensates for compact stars
is analyzed: the early onset of quark matter in the nonlocal models may help to
stabilize hybrid star configurations. While the anisotropic blue quark pairing
does not survive a big asymmetry in flavor space as imposed by the charge
neutrality condition, the CSL phase as a flavor independent pairing can be
realized as neutral matter in compact star cores. However, smooth form factors
and the missmatch between the flavor chemical potential in neutral matter make
the effective gaps of the order of magnitude $\simeq 10$ keV, and a more
systematic analysis is needed to decide whether such small gaps could be
consistent with the cooling phenomenology.


title:
Coherent and incoherent radiation from high-energy electron and the LPM
  effect in oriented single crystal

abstract:
  The process of radiation from high-energy electron in oriented single crystal
is considered using the method which permits inseparable consideration of both
coherent and incoherent mechanisms of photon emission. The total intensity of
radiation is calculated. The theory, where the energy loss of projectile has to
be taken into account, agrees quite satisfactory with available CERN data. It
is shown that the influence of multiple scattering on radiation process is
suppressed due to action of crystal field.


title:
Efficient Coannihilation Process through Strong Higgs Self-Coupling in
  LKP Dark Matter Annihilation

abstract:
  We point out that the lightest Kaluza-Klein particle (LKP) dark matter in
universal extra dimension (UED) models efficiently annihilates through the
coannihilation process including the first KK Higgs bosons when the Higgs mass
is slightly heavy as 200 - 230 GeV, which gives the large Higgs self-coupling.
The large self-coupling naturally leads the mass degeneracy between the LKP and
the first KK Higgs bosons and large annihilation cross sections of the KK Higgs
bosons. These are essential for the enhancement of the annihilation of the LKP
dark matter, which allows large compactification scale \sim 1 TeV to be
consistent with cosmological observations for the relic abundance of dark
matter. We found that the thermal relic abundance of the LKP dark matter could
be reconciled with the stringent constraint of electroweak precision
measurements in the minimal UED model.


title:
Multi-jet production in lepton-proton scattering at next-to-leading
  order accuracy

abstract:
  I summarize the theoretical and experimental status of multijet production in
DIS. I present the state of the art theoretical predictions and compare those
to the corresponding experimental results obtained by analysing the data
collected by the H1 and ZEUS collaborations at HERA. I also show new
predictions for three-jet event-shape distributions at the NLO accuracy.


title: Effects of heavy Majorana neutrinos at lepton-proton colliders

abstract:
  We discuss the prospects of detecting the processes
$e^+p\to\bar\nu_e\ell^+\ell'^+X$ and $\nu_ep\to e\ell^+\ell'^+X$
($\ell,\ell'=e,\mu,\tau$) under the conditions of the present $ep$ collider
HERA and of future colliders. These high-energy processes are assumed to be
mediated by the exchange of heavy Majorana neutrinos (HMN). We consider two
simple scenarios for the HMN mass spectrum: the effective singlet ($m_1\ll
m_2<m_3...$) and the effective doublet ($m_1<m_2\ll m_3...$). For the latter
case, the cross section includes information about CP-violating phases.


title: Radiative leptonic decays of heavy mesons in heavy quark limit

abstract:
  We study the radiative leptonic decays of heavy mesons within the covariant
light-front model. Using this model, both the form factors F_V and F_A have the
same form when the heavy quark limit is taken. In addition, the relation
between the form factor F_V and the decay constant of heavy meson F_H is
obtained. The hadronic parameter \beta can be determine by the parameters
appearing in the wave function of heavy meson. We find that the value of \beta
is not only quite smaller than the one in the non-relativistic case, but also
insensitive to the value of light quark mass m_q. These results mean that the
relativistic effects are very important in this work. We also obtain the
branching ratio of B\to l\nu_l \gamma is about (1.40-1.67)\times 10^{-6}, in
agreement with the general estimates in the literature.


title: Rare K -> pi nu nubar Decays

abstract:
  We present a concise review of the theoretical status of rare K -> pi nu
nubar decays in the standard model (SM). Particular attention is thereby
devoted to the recent calculation of the next-to-next-to-leading order (NNLO)
corrections to the charm quark contribution of K^+ -> pi^+ nu nubar, which
removes the last relevant theoretical uncertainty from the K -> pi nu nubar
system.


title: Strong one-pion decay of ground state charmed baryons

abstract:
  We evaluate the widths for the strong decays $\Sigma_c\to\Lambda_c \pi$,
$\Sigma_c^*\to\Lambda_c \pi$ and $\Xi_c^{*}\to\Xi_c \pi$. The calculations have
been done within a nonrelativistic constituent quark model with wave functions
that take advantage of the constraints imposed by heavy quark symmetry. Partial
conservation of axial current hypothesis allows us to determine the strong
vertices from an analysis of the weak axial current matrix elements. Our
results are in good agreement with experimental data.


title: Maximal Neutrino Mixing from Discrete Symmetry in Extra Dimensions

abstract:
  I review the construction of a model for lepton masses based on the flavour
symmetry group A4 x U(1) reproducing the so-called tri-bimaximal lepton mixing
scheme, in eccelent agreement with current data. The model predicts a neutrino
spectrum of normal hierarchy type, not far from degenerate. A testable relation
between neutrino masses is obtained. I shortly discuss also general
requirements for models based on spontaneously broken flavour symmetries, in
order to get a maximal atmospheric mixing angle.


title: Low scale Seesaw model and Lepton Flavor Violating Rare B Decays

abstract:
  We study lepton flavor number violating rare B decays, $b \to s l_h^{\pm}
l_l^{\mp}$, in a seesaw model with low scale singlet Majorana neutrinos
motivated by the resonant leptogenesis scenario. The branching ratios of
inclusive decays $ b \to s l_h^{\pm} \bar{l_l}^{\mp} $ with two almost
degenerate singlet neutrinos at TeV scale are investigated in detail. We find
that there exists a class of seesaw model in which the branching fractions of $
b \to s \tau \mu $ and $\tau \to \mu \gamma$ can be as large as $10^{-10}$ and
$10^{-9}$ within the reach of Super B factories, respectively, without being in
conflict with neutrino mixings and mass squared difference of neutrinos from
neutrino data, invisible decay width of $Z$ and the present limit of $Br(\mu
\to e \gamma)$.


title:
Four body decay of the lighter top-squark constrained by the Lighter
  CP-even Higgs boson mass bound

abstract:
  We reinvestigated the parameter space allowing a large BR of the 4-body decay
of the lighter top-squark ($\lstop$) accessible at Tevatron Run-II by imposing
the lighter CP-even Higgs boson mass ($\mlhiggs$) bound from LEP. Important
constraints were obtained in mSUGRA as well as in the unconstrained
supersymmetric models. Our results show that the prospect of searching the
lighter top-squark via the 4-body decay mode, in particular the $\ell + n-jets
+ \met$ signal, is not promising in mSUGRA due to the above bound on
$\mlhiggs$. The existing bounds on $\mlstop$ from Tevatron Run-I and LEP
assuming 100% BR of the loop decay of $\lstop$ are, therefore, valid to a good
approximation. We also find that large BRs of the above 4-body decay are
allowed in the unconstrained model over significant regions of parameter spaces
and the possibility that this decay mode is the main discovery channel at
Tevatron Run-II is open. We have briefly reviewed the theoretical uncertainties
in the calculation of $\mlhiggs$ and their consequences for the constraints
obtained by us. We have commented upon, with illustrative examples, how the
above parameter space is affected if future experiments push the Higgs boson
mass bound upward.


title: Next Generation Multi-particle event generators for the MSSM

abstract:
  We present a next generation of multi-particle Monte Carlo (MC) Event
generators for LHC and ILC for the MSSM, namely the three program packages
Madgraph/MadEvent, WHiZard/O'Mega and Sherpa/Amegic++. The interesting but
difficult phenomenology of supersymmetric models at the upcoming colliders
demands a corresponding complexity and maturity from simulation tools. This
includes multi-particle final states, reducible and irreducible backgrounds,
spin correlations, real emission of photons and gluons, etc., which are
incorporated in the programs presented here. The framework of a model with such
a huge particle content and as complicated as the MSSM makes strenuous tests
and comparison of codes inevitable. Various tests show agreement among the
three different programs; the tables of cross sections produced in these tests
may serve as a future reference for other codes. Furthermore, first MSSM
physics analyses performed with these programs are presented here.


title:
Unintegrated gluon distributions in D* and dijet associated
  photoproduction at HERA

abstract:
  We consider the photoproduction of D* mesons associated with two hadron jets
at HERA collider in the framework of the kt-factorization approach. The
unintegrated gluon densities in a proton are obtained from the full CCFM, from
unified BFKL-DGLAP evolution equations as well as from the Kimber-Martin-Ryskin
prescription. Resolved photon contributions are reproduced by the initial-state
gluon radiation. We investigate different production rates and make comparison
with the recent experimental data taken by the ZEUS collaboration. Special
attention is put on the specific dijet correlations which can provide unique
information about non-collinear gluon evolution dynamics.


title: The Unitarity Triangle through $B_d\to \rho^{\pm} \pi^{\mp}$ decays

abstract:
  We analyze the impact of the CP-violating observables in the $B_d\to
\rho^{\pm} \pi^{\mp}$ system, combined with the precise measurement of
$\sin2\beta$, in the extraction of the CKM matrix. We explore two strategies
for determining the Unitarity Triangle in these modes. Computing the penguin
parameters $(r_{\pm}, \phi_{\pm})$ and the ratio of two trees $(r_{t},
\phi_{t})$ within QCD factorization yields a precise determination of
$(\bar\rho, \bar\eta)$, reflected by a weak dependence on $\phi_{\pm}$, which
is shown to be a second order effect, as in the $B_d \to \pi^+ \pi^-$ system.
Moreover, we find that the dependence on penguin amplitudes $r_{\pm}$ in
$B_d\to \rho^{\pm} \pi^{\mp}$ is less pronounced than in the $B_d \to \pi^+
\pi^-$ case, since penguin contributions $r_{\pm}\approx r_{\pi\pi}/3$,
implying an important simplification in our analysis. Independent experimental
tests of the factorization framework are proposed and discussed, using $B_d \to
\pi^+ \pi^-$ and $B_d \to \rho^{\pm} \rho^{\mp}$ modes.


title: Quark-Hadron Duality in the Rein-Sehgal Model

abstract:
  The quark-hadron duality in CC and NC neutrino interactions is discussed
under assumptions that single pion production is described accurately by the
Rein-Sehgal model and that it allows reconstruction of the inclusive cross
section in the resonance region. The duality is measured by means of integrals
of structure functions in the Nachtmann variable for $Q^2<3$ GeV$^2$. The
results depend on the precision with which contributions from single pion
production channels in the overall cross sections are known. Several approaches
to evaluate them are compared. The duality is predicted to be seen for proton
target reactions and to be absent for neutron and isoscalar targets.
Two-component duality between resonant and valence quark contributions to
structure functions is also investigated.


title: Supersymmetric approximations to the 3D supersymmetric O(N) model

abstract:
  We develop several non-perturbative approximations for studying the dynamics
of a supersymmetric O(N) model which preserve supersymmetry. We study the phase
structure of the vacuum in both the leading order in large-N approximation as
well as in the Hartree approximation, and derive the finite temperature
renormalized effective potential. We derive the exact Schwinger-Dyson equations
for the superfield Green functions and develop the machinery for going beyond
the next to leading order in large-N approximation using a truncation of these
equations which can also be derived from a two-particle irreducible effective
action.


title: Soft-gluon corrections to hard-scattering cross sections through NNNLO

abstract:
  I present a systematic approach to calculating soft-gluon corrections through
next-to-next-to-next-to-leading order for arbitrary hard-scattering cross
sections. Using a unified approach, master formulas are derived for processes
with both simple and complex color flows. Applications and numerical results
are given for some processes of interest, including charged Higgs production
and top quark production in the Standard Model and beyond.


title: A scenario for leptogenesis at the TeV scale

abstract:
  We propose a scenario of thermal leptogenesis at the TeV scale in the context
of an extension of the Standard Model with 4 generations. We also add one
right-handed Majorana neutrino for each generation to generate left handed
neutrino masses via see-saw. The r\^{o}le of the fourth lepton doublet is not
much different from that of a supersymmetric partner, so the leptogenesis
consequences of a four generation scenario are indicators of a more generic
picture. We obtain a value for the baryon asymmetry of the
  Universe in accordance with observations by solving the full set of coupled
Boltzmann equations for this model.


title:
The tension between gauge coupling unification, the Higgs boson mass,
  and a gauge-breaking origin of the supersymmetric mu-term

abstract:
  We investigate the possibility of generating the $\mu$-term in the MSSM by
the condensation of a field that is a singlet under the SM gauge group but
charged under an additional family-independent $U(1)_X$ gauge symmetry. We
attempt to do so while preserving the gauge coupling unification of the MSSM.
For this, we find that SM non-singlet exotics must be present in the spectrum.
We also prove that the pure $U(1)_X$ anomalies can always be solved with
rationally charged fields, but that a large number of SM singlets are often
required. For $U(1)_X$ charges that are consistent with an embedding of the
MSSM in SU(5) or SO(10), we show that the $U(1)_X$ charges of the MSSM states
can always be expressed as a linear combination of abelian subgroups of $E_6$.
However, the SM exotics do not appear to have a straightforward embedding into
GUT multiplets. We conclude from this study that if this approach to the
$\mu$-term is correct, as experiment can probe, it will necessarily complicate
the standard picture of supersymmetric grand unification.


title: CPT violation in the top sector

abstract:
  We study the viability of observation of CPT violation in the top sector at
future colliders. We show possible studies and different estimates for hadronic
and linear colliders. In particular, we will present current constraints for
Tevatron and prospects for the LHC and the ILC.


title: Short study of the eta-eta' system in the two mixing angle scheme

abstract:
  A two mixing angle description of the pseudoscalar decay constants associated
to the $\eta$-$\eta^\prime$ system is used to parametrize the theoretical
amplitudes of the radiative decays $(\eta,\eta^\prime)\to\gamma\gamma$ and the
coupling constants $g_{V(\eta,\eta^\prime)\gamma}$ with $V=\rho,\omega,\phi$.
The parametrization is performed in both the ``octet-singlet'' basis and the
``quark-flavour'' basis. An excellent agreement with the most recent
experimental data is achieved. Our analysis reveals that at the present
experimental accuracy the two mixing angles differ significantly in the former
basis but not in the latter, in accordance with the expectations of large $N_c$
Chiral Perturbation Theory where the difference between the two mixing angles
are due to a $SU(3)_f$-breaking effect and a violation of the OZI rule
respectively.


title:
Virtual Corrections to Bremsstrahlung with Applications to Luminosity
  Processes and Radiative Return

abstract:
  We will describe radiative corrections to bremsstrahlung, focusing on
applications to luminosity, fermion pair production, and radiative return at
high-energy e+ e- colliders. A precise calculation of the Bhabha luminosity
process was essential at SLC and LEP, and will be equally important in ILC
physics. We will review the exact results for two-photon radiative corrections
to Bhabha scattering which led to the precision estimates for the BHLUMI MC. We
will also compare the implementation of the virtual photon correction to
bremsstrahlung for fermion pair production in the KK MC to similar exact
expressions developed for other purposes, and discuss applications to radiative
return in high energy e+ e- colliders.


title:
Quark-Lepton Complementarity with Renormalization Effects through
  Threshold Corrections

abstract:
  The recent experimental measurements of the solar neutrino mixing angle
$\theta_{sol}$ and the Cabibbo mixing angle $\theta_C$ reveal a surprising
relation, $ \theta_{sol}+\theta_C \simeq \frac{\pi}{4} $. We review that while
this empirical relation has been interpreted as a support of the idea of grand
unification, it may be merely accidental in the sense that reproducing the
relation at a low energy in the framework of grand unification may depend
strongly on the renormalization effects whose size can vary with the choice of
parameter space. We note that the lepton mixing matrix derived from
quark-lepton unification can lead to a shift of the complementarity relation at
low energy. While the renormalization group effects generally lead to additive
contribution on top of the shift, we show that the threshold corrections which
may exist in some intermediate scale new physics such as supersymmetric
standard model can diminish it, so we can achieve the complementarity relation
at a low energy.


title: Quark-Lepton universality and large leptonic mixing

abstract:
  A unified description of fermionic mixing is proposed which assumes that in
certain basis ($i$) a single complex unitary matrix $V$ diagonalizes mass
matrices of all fermions to the leading order, ($ii$) the SU(5) relation
$M_d=M_l^T$ exists between the mass matrices of the down quarks and the charged
leptons, and ($iii$) $M_d^\dagger=M_d$. These assumptions automatically lead to
different mixing patterns for quarks and leptons: quarks remain unmixed to
leading order ($i. e. V_{CKM}=1$) while leptons have non-trivial mixing given
by a symmetric unitary matrix $V^0_{PMNS} = V^T V$. $V$ depends on two physical
mixing angles and for values of these angles $\sim 20^\circ-25 ^\circ$ it
reproduces the observed mixing patterns rather well. We identify conditions
under which the universal mixing $V$ follows from the universal mass matrices
of fermions. Relatively small perturbations to the leading order structure lead
to the CKM mixing and corrections to $V^0_{PMNS}$. We find that if the
correction matrix equals the CKM matrix, the resulting lepton mixing agrees
well with data and predicts $\sin \theta_{13} > 0.08$. In a more general
context, the assumption of partial universality ($i.e.$, different mixing for
the up and the down components of doublets) is shown to lead to a
complementarity relation $V_{PMNS}V_{CKM}=V^TV$ in the lowest order.


title: The transverse-momentum distribution of the Higgs boson at the LHC

abstract:
  We present QCD predictions for the transverse momentum (q_T) distribution of
the Higgs boson at the LHC. At small q_T the logarithmically-enhanced terms are
resummed to all orders up to next-to-next-to-leading logarithmic accuracy. The
resummed component is consistently matched to the next-to-leading order
calculation valid at large q_T. The results, which implement the most advanced
perturbative predictions available at present for this observable, show a good
stability with respect to theoretical uncertainties. The numerical program HqT,
used to perform the calculation, is briefly discussed.


title:
Three-loop electroweak corrections to the rho-parameter, sin^2 theta_eff
  and the W-boson mass in the large Higgs mass limit

abstract:
  A review of the calculation of the leading three-loop electroweak corrections
to the rho-parameter, sin^2 theta_eff and the W-boson mass is presented. The
heavy Higgs mass expansion and the renormalization are discussed.


title:
A new jet algorithm based on the k-means clustering for the
  reconstruction of heavy states from jets

abstract:
  A jet algorithm based on the k-means clustering procedure is proposed which
can be used for the invariant-mass reconstruction of heavy states decaying to
hadronic jets. The proposed algorithm was tested by reconstructing E+ E- to
ttbar to 6 jets and E+ E- to W+W- to 4 jets processes at \sqrt{s}=500 GeV using
a Monte Carlo simulation. It was shown that the algorithm has a reconstruction
efficiency similar to traditional jet-finding algorithms, and leads to 25% and
40% reduction of reconstruction width for top quarks and W bosons,
respectively, compared to the kT (Durham) algorithm. In addition, it is
expected that the peak positions measured with the new algorithm have smaller
systematical uncertainty.


title: SUSY parameter determination

abstract:
  The impact of the LHC, SLHC and the ILC on the precision of the determination
of supersymmetric parameters is investigated. In particular, in the point SPS1a
the measurements performed at the ILC will improve by an order of magnitude the
precision obtained by the LHC alone. The SLHC with respect to the LHC has the
potential to reduce the errors by a factor two.


title:
Neutrino-Nuclear Coherent Scattering and the Effective Neutrino Charge
  Radius

abstract:
  We propose to extract the value of the effective neutrino charge radius from
the coherent scattering of a neutrino against a heavy nucleus. In such an
experiment the relevant quantity to measure is the kinetic energy distribution
of the recoiling nucleus, which, in turn, may be directly related to the shift
in the value of the effective weak mixing angle produced by the neutrino charge
radius. This type of experiment has been proposed in order to observe the
coherent elastic neutrino-nuclear scattering for the first time. If interpreted
in the way suggested in this work, such an experiment would constitute the
first terrestrial attempt to measure this intrinsic electromagnetic property of
the neutrino.


title: Displacement Operator Formalism

abstract:
  We review the D-formalism, a new method for determining the renormalization
of Green functions to all orders in perturbation theory. This formalism
exploits the fact that the renormalized Green functions may be calculated by
displacing by an infinite amount the renormalized fields and parameters of the
theory with respect to the unrenormalized ones. We briefly discuss some of its
main characteristics, its conceptual and practical advantages, and some new
results obtained through it.


title: Neutrino propagation and quantum states in matter

abstract:
  We briefly review the matter effects in case of Dirac and Majorana neutrino
propagation in medium. We develop the quantum treatment of neutrinos in matter:
using the generalized Dirac equations for Dirac and Majorana neutrinos wave
functions in matter we get the explicit expressions for the corresponding Green
functions.


title: New Aspects of B -> pi pi, pi K and their Implications for Rare Decays

abstract:
  We analyse the B -> pi pi, pi K modes in the light of the most recent
B-factory data, and obtain the following new results: (i) the B0 -> pi+ pi-,
pi- K+ modes prefer gamma=(74+-6)deg, which - together with |V_ub/V_cb| -
allows us to determine the ``true'' unitarity triangle and to search for
CP-violating new-physics contributions to B0_d-\bar B0_d mixing; (ii) the B ->
pi K puzzle reflected in particular by the low experimental value of the ratio
R_n of the neutral B -> pi K rates persists and still favours new physics in
the electroweak penguin sector with a new CP-violating phase phi ~ -90deg,
although now also phi ~ +90deg can bring us rather close to the data; (iii) the
mixing-induced B0 -> pi0 K_S CP asymmetry is a sensitive probe of the sign of
this phase, and would currently favour phi ~ +90deg, as well as the direct CP
asymmetry of B+- -> pi0 K+-, which suffers, however, from large hadronic
uncertainties; (iv) we investigate the sensitivity of our B -> pi K analysis to
large non-factorizable SU(3)-breaking effects and find that their impact is
surprisingly small so that it is indeed exciting to speculate on new physics;
(v) assuming that new physics enters through Z0 penguins, we study the
interplay between B -> pi K and rare B, K decays and point out that the most
recent B-factory constraints for the latter have interesting implications,
bringing us to a few scenarios for the future evolution of the data, where also
the mixing-induced CP violation in B0 -> pi0 K_S plays a prominent role.


title: Detection of elastic photon-photon scattering through four-wave coupling

abstract:
  According to the theory of quantum electrodynamics, photon-photon scattering
can take place via exchange of virtual electron-positron pairs. Effectively,
the interaction can be formulated in terms of non-linear corrections to
Maxwell's equations, and hence may be treated by classical non-linear
electrodynamics. Due to the strong electromagnetic fields needed to reach any
noticeable effect, photon-photon scattering has not yet been observed
experimentally, but recent improvements in laser technology have increased the
possibility of direct detection. A verification of the phenomena would be of
great scientific value as a confirmation of quantum electrodynamics. In this
thesis the possibility of direct detection of elastic photon-photon scattering
through four-wave coupling is investigated, both for current and future
systems. It is shown how three colliding laser pulses satisfying certain
matching conditions, can generate scattered radiation in a fourth resonant
direction. The interaction is modeled, and the number of scattered photons is
estimated for optimized configurations of incoming pulses, both for the Vulcan
laser at the Rutherford Appleton Laboratory as well as for the planned XFEL at
DESY. An experiment using the Vulcan laser is predicted to produce 22 scattered
photons per shot, an amount which is definitely detectable. The usefulness of
the XFEL highly depends on future developments in laser technology, but a
realistic estimation gives a result of 30000 scattered photons per second.


title:
Transversity and the Polarized Drell-Yan Process in $p\bar{p} \to \mu
  ^{+}\mu ^{-}X$

abstract:
  Estimates are given for the double spin asymmetry in lepton-pair production
from collisions of transversely polarized protons and antiprotons for the
kinematics of the recently proposed PAX experiment at GSI on the basis of
predictions for the transversity distribution from the probabilistic
quark-parton model developed earlier.


title:
Evolution of the concept of Quark Matter: the Ianus face of the heavy
  ion collisions

abstract:
  Since the beginning of the efforts to produce and understand quark matter
large changes developed in the ideas of description of this matter. In the
present paper we summarize some aspects of this development.


title: Non-minimal models of supersymmetric spontaneous CP violation

abstract:
  We briefly review the question of spontaneous CP violation in some models of
weak interactions. The next-to-minimal supersymmetric standard model, with two
Higgs doublets and one gauge singlet, is one of the minimal extensions of the
standard model where SCPV is viable. We analyse the possibility of spontaneous
CP violation in the next-to-minimal supersymmetric standard model with an extra
singlet tadpole term in the scalar potential, and confirm the existence of
phenomenologically consistent minima with non-trivial CP violating phases.


title: Tree-Level Vacuum Stability in Multi Higgs Models

abstract:
  In the most general model with two Higgs doublets, if a minimum that
preserves the $U(1)_{em}$ symmetry exists, then charge breaking (CB) minima
cannot occur. The depth of the potential at a stationary point that breaks CB
or CP, relative to the $U(1)_{em}$ preserving minimum, is proportional to the
squared mass of the charged or pseudoscalar Higgs, respectively.


title:
$\nu_\mu$ disappearance at the SPL, T2K-I, NO$\nu$A and the Neutrino
  Factory

abstract:
  We study the measurement of the atmospheric neutrino oscillation parameters,
$\theta_{23}$ and $\Delta m^2_{23}$, at the $\nu_\mu$ disappearance channel at
three conventional beam facilities, the SPL, T2K-phase I and NO$\nu$A. These
two parameters have been shown to be of crucial importance in the measurement
of two of the unknowns of the PMNS mixing matrix, $\theta_{13}$ and the
leptonic CP-violating phase $\delta$. In our analyis, the effect of the two
discrete ambiguities, ${\rm sign}(\Delta m^2_{23})$ and ${\rm sign}(\tan 2
\theta_{23})$, is explicitly taken into account. We analyse also the $\nu_\mu$
disappearance channel at the Neutrino Factory, and combine it with the
``golden'' $\nu_e \to \nu_\mu$ and ``silver'' $\nu_e \to \nu_\tau$ appearance
channels to study its impact on the measurement of $\theta_{13}$ and $\delta$.
Eventually, we present the sensitivity of the four facilities to different
observables: $\theta_{13}$, $\delta$, maximal $\theta_{23}$, the sign of the
atmospheric mass difference, $s_{atm}$, and the $\theta_{23}$-octant,
$s_{oct}$.


title: Status of the Cabibbo Angle

abstract:
  We review the recent experimental and theoretical progress in the
determination of |V_{ud}| and |V_{us}|, and the status of the most stringent
test of CKM unitarity. Future prospects on |V_{cd}| and |V_{cs}| are also
briefly discussed.


title: Multiparticle correlations in Q-space

abstract:
  We introduce Q-space, the tensor product of an index space with a primary
space, to achieve a more general mathematical description of correlations in
terms of q-tuples. Topics discussed include the decomposition of Q-space into a
sum-variable (location) subspace S plus an orthogonal difference-variable
subspace D, and a systematisation of q-tuple size estimation in terms of
p-norms. The "GHP sum" prescription for q-tuple size emerges naturally as the
2-norm of difference-space vectors. Maximum- and minimum-size prescriptions are
found to be special cases of a continuum of p-sizes.


title:
A quark model suggestion against Ds*(2317) and Ds*(2460) as chiral
  partners of standard Ds

abstract:
  This paper presents the first study of mesons with a quark and an antiquark
with different and finite masses, in a simple confining and chiral invariant
quark-antiquark interaction, leading to spontaneous chiral symmetry breaking
and to constituent quarks. In the false chiral invariant vacuum, the chiral
partners are degenerate, and tachyons occur in the light-light spectrum. In the
true vacuum, most of the standard non-relativistic quark model spectra should
be recovered except for the pion and other particular constraints. The
calibration problem of chiral quark models is also addressed here. The detailed
inspection of the different contributions to the D and Ds masses suggests that
the challenging recently observed Ds*(2317) and Ds*(2460) mesons might not fit
as global chirally rotated quark-antiquark Ds mesons.


title: Background field method at finite temperature and density

abstract:
  In this letter we make use of the Background Field Method (BFM) to compute
the effective potential of an SU(2) gauge field theory, in the presence of
chemical potential and temperature. The main idea is to consider the chemical
potential as the background field. The gauge fixing condition required by the
BFM turns out to be exactly the one we found in a previous article in a
different context.


title: Stressed pairing in conventional color superconductors is unavoidable

abstract:
  At sufficiently high densities, cold dense three-flavor quark matter is in
the color-flavor locked (CFL) phase, in which all nine quarks pair in a
particularly symmetric fashion. Once the heaviness of the strange quark (mass
$m_s$) and the requirements of electric and color neutrality are taken into
account, the CFL pattern of color superconductivity requires the pairing of
quarks that would, in the absence of pairing, have Fermi momenta that differ by
of order $m_s^2/\mu$, with $\mu$ the quark number chemical potential. This
means that at sufficiently small $\mu$, the ``stress'' on the pairing is large
enough that the system can lower its energy by breaking pairs, resulting in
some unconventional color superconductor which includes gapless excitations,
spatial inhomogeneity, counter-propagating currents, or all three. In this
paper we ask whether there is some less symmetric but still conventional
pattern of pairing that can evade the stress. In other words, is there a
pattern of pairing in which, once electric and color neutrality are imposed by
suitable chemical potentials, pairing only occurs among those quarks whose
Fermi momenta would be equal in the absence of pairing? We use
graph-theoretical methods to classify 511 patterns of conventional color
superconducting pairing, and show that none of them meet this requirement. All
feel a stress, and all can be expected to become unstable to gapless modes at a
density comparable to that at which the CFL phase becomes unstable.


title:
Solving the Cosmic Lithium Problems with Gravitino Dark Matter in the
  CMSSM

abstract:
  Standard Big Bang nucleosynthesis at baryonic density as inferred by WMAP
implies a primordial Li7 abundance factor of two to three larger than that
inferred by observations of low--metallicity halo stars. Recent observations of
Li6 in halo stars suggest a pre--galactic origin of this isotope, which is
exceedingly difficult to explain by putative high redshift cosmic ray
populations. We investigate if one or both of these lithium problems may be
solved by late decaying relic particles in the Constrained Minimal
Supersymmetric Standard Model (CMSSM) coupled to gravity. Assuming that the
gravitino is the lightest supersymmetric particle (LSP) we find that in large
parts of the CMSSM parameter space either of these problems can be potentially
solved. In particular, we also find solutions where both lithium problems may
be solved simultaneously. These entail the hadronic decay of relic 1 TeV staus
into 100 GeV gravitinos at 1000 sec after the Big Bang, as proposed by one of
us before. Moreover, the produced gravitinos naturally contribute a large
fraction, or all, to the by WMAP required dark matter density. A prediction of
this model is the dark matter to be lukewarm with free--streaming lengths of
the order of a 4 keV early freezing--out relic particle. Such lukewarm
gravitino dark matter may have beneficial effects to the formation of galactic
structures and may be constrained by the reionisation history of the Universe.
The current version of the paper presents results for both cases (a) when
catalytic nuclear reations are included and (b) when they are neglected.


title: A Modified "Bottom-up" Thermalization in Heavy Ion Collisions

abstract:
  In the initial stage of the bottom-up picture of thermalization in heavy ion
collisions, the gluon distribution is highly anisotropic which can give rise to
plasma instability. This has not been taken account in the original paper. It
is shown that in the presence of instability there are scaling solutions, which
depend on one parameter, that match smoothly onto the late stage of bottom-up
when thermalization takes place.


title: FCNCs in supersymmetric multi-Higgs doublet models

abstract:
  We conduct a general discussion of supersymmetric models with three families
in the Higgs sector. We analyse the scalar potential, and investigate the
minima conditions, deriving the mass matrices for the scalar, pseudoscalar and
charged states. Depending on the Yukawa couplings and the Higgs spectrum, the
model might allow the occurrence of potentially dangerous flavour changing
neutral currents at the tree-level. We compute model-independent contributions
for several observables, and as an example we apply this general analysis to a
specific model of quark-Higgs interactions, discussing how compatibility with
current experimental data constrains the Higgs sector.


title:
Properties of the light scalar mesons face the experimental data on the
  $\phi\to\pi^0\pi^0\gamma$ decay and the $\pi\pi$ scattering

abstract:
  The high-statistical KLOE data on the $\phi\to\pi^0\pi^0\gamma$ decay are
described simultaneously with the data on $\pi\pi$ scattering and the
$\pi\pi\to K\bar K$ reaction. The description is carried out taking into
account the chiral shielding of the putative $\sigma (600)$ meson and it's
mixing with the well-established $f_0(980)$ meson. It is shown that the data
don't contradict the existence of the $\sigma (600)$ meson and yield evidence
in favor of the four-quark nature of the $\sigma (600)$ and $f_0(980)$ mesons.