title:
Effective Potential of Super Yang-Mills theory on M^4\times S^1 and
  related topics

abstract:
  We study the gauge symmetry breaking of an ${\cal N}=1$ supersymmetric
Yang-Mills theory defined on $M^4\times S^1$, taking correctly account of the
vacuum expectation values for the adjoint scalar field $\vev{\Sigma}$ in vector
multiplet in addition to the Wilson line phases $\vev{A_y}$. We evaluate the
one-loop effective potential and obtain the vacuum configuration, for which an
SU(N) gauge symmetry is not broken. In case of an orbifold $S^1/Z_2$, under
appropriate orbifolding boundary conditions, two Higgs doublets are embedded in
the zero modes, $A_y^{(0)}$ and $\Sigma^{(0)}$. We point out that the
tree-level scalar potential resulted from the covariant derivative for the
adjoint scalar field is identical to the $D$-term of the MSSM. We also briefly
mention the mass spectra of the gauge and Higgs sector in the theory.


title: Charmonium's K2 peak

abstract:
  The newly reported Y(4260) becomes the second most massive state in the
charmonium family. We argue that it displaces the psi(4415) as the (largely) 4s
vector charmonium state, recall s-d wave interference to explain the lack of a
signal in e-e+ to hadrons and suggest some further study avenues that can
exclude exotic meson assignments. The absence of a J/psi KK mode can be
understood, beyond phase space suppression, to be a consequence of chiral
symmetry. We also provide a model calculation in this sector showing that,
although forcing the fit somewhat (which suggests a small sea quark
wavefunction component), the state can be incorporated in a standard scheme.


title: Higgs Localization in Split Fermion Models

abstract:
  The flavor puzzle of the Standard Model is explained in split fermion models
by having the fermions localized and separated in an extra dimension. Many of
these models assume a certain profile for the Higgs VEV, usually uniform, or
confined to a brane, without providing a dynamical realization for it. By
studying the effect of the coupling between the Higgs and the localizer fields,
we obtain these scenarios as results, rather than ansaetze. Moreover, we
discuss other profiles and show that they are phenomenologically viable.


title: New physics in e+ e- -> Z gamma with polarized beams

abstract:
  We present a complete description of angular distributions in the presence of
new interactions for the process e+ e- -> Z gamma with polarized beams at
future linear colliders, by considering the most general form-factors allowed
by gauge invariance. We include the possibility of CP violation, and classify
the couplings according to their CP properties. Chirality conserving and
chirality violating couplings give rise to distinct dependence on beam
polarization. We present a comprehensive discussion including both types of
couplings and provide a detailed comparison of the effects due to each. We
discuss some selected asymmetries which would enable isolating effects of the
CP-violating form-factors. We also present sensitivities on the corresponding
couplings achievable at a future linear collider with realistic polarization
and luminosity.


title: Double diffractive rho-production in gamma^* gamma^* collisions

abstract:
  We present a first estimate of the cross-section for the exclusive process
gamma^*_L (Q_1^2) gamma^*_L(Q_2^2) -> rho^0_L rho^0_L, which will be studied in
the future high energy e^+ e^- linear collider. As a first step, we calculate
the Born order approximation of the amplitude for longitudinally polarized
virtual photons and mesons, in the kinematical region s >> -t, Q_1^2, Q_2^2.
This process is completely calculable in the hard region Q_1^2, Q_2^2 >>
Lambda^2_{QCD}. We perform most of the steps in an analytical way. The
resulting cross-section turns out to be large enough for this process to be
measurable with foreseen luminosity and energy, for Q_1^2 and Q_2^2 in the
range of a few GeV^2.


title: The Quark Form Factor at Higher Orders

abstract:
  We study the electromagnetic on-shell form factor of quarks in massless
perturbative QCD. We derive the complete pole part in dimensional
regularization at three loops, and extend the resummation of the form factor to
the next-to-next-to-leading contributions. These results are employed to
evaluate the infrared finite absolute ratio of the time-like and space-like
form factors up to the fourth order in the strong coupling constant. Besides
for the pole structure of higher-loop QCD amplitudes, our new contributions to
the form factor are also relevant for the high-energy limit of massive gauge
theories like QED. The highest-transcendentality component of our results
confirms a result recently obtained in N=4 Super-Yang-Mills theory.


title: Diffractive processes as a tool for searching for new physics

abstract:
  We show that the addition of detectors to tag the outgoing forward protons,
at the LHC, will significantly enlarge the potential of studying New Physics. A
topical example is Higgs production by the exclusive double-diffractive
process, pp -> p+H+p. We discuss the production of Higgs bosons in both the SM
and MSSM. We show how the predicted rates may be checked at the Tevatron by
observing the exclusive double-diffractive production of dijets, or $\chi_c$ or
$\chi_b$ mesons, or $\gamma \gamma$ pairs.


title: Pseudo-scalar Higgs production at next-to-leading order SUSY-QCD

abstract:
  The production rate of the CP-odd Higgs boson in the Minimal Supersymmetric
Standard Model is evaluated through next-to-leading order in the strong
coupling constant. The divergent integrals are regulated using Dimensional
Reduction, with a straightforward implementation of $\gamma_5$. The result is
confirmed within Dimensional Regularization where $\gamma_5$ is implemented
according to the Standard Model calculation of Chetyrkin et al. The well-known
Standard Model result is recovered if the masses of the supersymmetric
particles tend to infinity.


title: Impact of large-x resummation on parton distribution functions

abstract:
  We investigate the effect of large-x resummation on parton distributions by
performing a fit of Deep Inelastic Scattering data from the NuTeV, BCDMS and
NMC collaborations, using NLO and NLL soft-resummed coefficient functions. Our
results show that soft resummation has a visible impact on quark densities at
large x. Resummed parton fits would therefore be needed whenever high precision
is required for cross sections evaluated near partonic threshold.


title: Heavy flavours: theory summary

abstract:
  I summarize the theory talks given in the Heavy Flavours Working Group. In
particular, I discuss heavy-flavour parton distribution functions, threshold
resummation for heavy-quark production, progress in fragmentation functions,
quarkonium production, heavy-meson hadroproduction.


title: Neutrinos in Supersymmetry

abstract:
  We briefly review the neutrino mass generation mechanism in supersymmetry
with Bilinear R-Parity Violation in Minimal Supergravity and Anomaly Mediated
Supersymmetry Breaking.


title:
Bi-large Neutrino Mixing and CP violation in an SO(10) SUSY GUT for
  Fermion Masses

abstract:
  We construct a simple SO(10) SUSY GUT with $D_3$ family symmetry and low
energy R parity. The model describes fermion mass matrices with 14 parameters
and gives excellent fits to 20 observable masses and mixing angles in both
quark and lepton sectors, giving 6 predictions. Bi-large neutrino mixing is
obtained with hierarchical quark and lepton Yukawa matrices; thus avoiding the
possibility of large lepton flavor violation. The model naturally predicts
small 1-3 neutrino mixing, $\sin \theta_{13} \simeq 0.05$, and a CP violating
phase $\delta$ close to $\pi/2$. Among other interesting predictions is a tiny
effective Majorana mass for neutrinoless double-beta decay. Leptogenesis is
also possible with the decay of the lightest right-handed neutrino giving an
acceptable CP violating asymmetry $\epsilon_1$ of order $10^{-6}$, {\em and
with the correct sign for the resultant baryon asymmetry}. We also show how
similar models with the non-abelian symmetry groups SU(2) or $D_4$, instead of
$D_3$, can be constructed.


title: Resonant CP Violation in Higgs Radiation at e^+e^- Linear Collider

abstract:
  We study resonant CP violation in the Higgsstrahlung process e^+e^- ->
H_{1,2,3} (Z -> e^+e^-, \mu^+\mu^-) and subsequent decays H_{1,2,3} -> b
\bar{b}, \tau^-\tau^+, in the MSSM with Higgs-sector CP violation induced by
radiative corrections. At a high-energy e^+e^- linear collider, the recoil-mass
method enables one to determine the invariant mass of a fermion pair produced
by Higgs decays with a precision as good as 1 GeV. Assuming an integrated
luminosity of 100/fb, we show that the production lineshape of a coupled system
of neutral Higgs bosons decaying into b\bar{b} quarks is sensitive to the
CP-violating parameters. When the Higgs bosons decay into \tau^-\tau^+, two CP
asymmetries can be defined using the longitudinal and transverse polarizations
of the tau leptons. Taking into account the constraints from electric dipole
moments, we find that these CP asymmetries can be as large as 80 %, in a
tri-mixing scenario where all three neutral Higgs states of the MSSM are nearly
degenerate and mix significantly.


title: Two-Loop Bhabha Scattering in QED

abstract:
  In the context of pure QED, we obtain analytic expressions for the
contributions to the Bhabha scattering differential cross section at order
alpha^4 which originate from the interference of two-loop photonic vertices
with tree-level diagrams and from the interference of one-loop photonic
diagrams amongst themselves. The ultraviolet renormalization is carried out.
The IR-divergent soft-photon emission corrections are evaluated and added to
the virtual cross section. The cross section obtained in this manner is valid
for on-shell electrons and positrons of finite mass, and for arbitrary values
of the center of mass energy and momentum transfer. We provide the expansion of
our results in powers of the electron mass, and we compare them with the
corresponding expansion of the complete order alpha^4 photonic cross section,
recently obtained in hep-ph/0501120. As a by-product, we obtain the
contribution to the Bhabha scattering differential cross section of the
interference of the two-loop photonic boxes with the tree-level diagrams, up to
terms suppressed by positive powers of the electron mass. We evaluate
numerically the various contributions to the cross section, paying particular
attention to the comparison between exact and expanded results.


title:
Inequalities for nucleon generalized parton distributions with helicity
  flip

abstract:
  Several positivity bounds are derived for generalized parton distributions
(GPDs) with helicity flip.


title: Interpolating between low and high energy QCD via a 5D Yang-Mills model

abstract:
  We describe the Goldstone bosons of massless QCD together with an infinite
number of spin-1 mesons. The field content of the model is SU(Nf)xSU(Nf)
Yang-Mills in a compact extra-dimension. Electroweak interactions reside on one
brane. Breaking of chiral symmetry occurs due to the boundary conditions on the
other brane, away from our world, and is therefore spontaneous. Our
implementation of the holographic recipe maintains chiral symmetry explicit
throughout. For intermediate energies, we extract resonance couplings. These
satisfy sum rules due to the 5D nature of the model. These sum rules imply,
when taking the high energy limit, that perturbative QCD constraints are
satisfied. We also illustrate how the 5D model implies a definite prescription
for handling infinite sums over 4D resonances. Taking the low energy limit, we
recover the chiral expansion and the corresponding non-local order parameters.
All local order parameters are introduced separately.


title: X(1835): A Possible Baryonium?

abstract:
  We point out that (1) the large $p\bar p$ coupling and suppressed mesonic
coupling of X(1835) and (2) the suppression of the three-body strange final
states strongly indicate that X(1835) may be a $p\bar p$ baryonium. We also
point out that the branching ratio of $X(1835)\to\eta \pi\pi$ should be bigger
than that of $X(1835)\to\eta^\prime \pi\pi$. If BES further confirms the
non-observation of X(1835) in the $\eta\pi\pi$ channel, that will be very
puzzling. Finally, X(1835) may be used a tetraquark generator if X(1835) is
really established as a baryonium state.


title: Micro-canonical pentaquark production in $\ee$ annihilations

abstract:
  The existence of pentaquarks, namely baryonic states made up of four quarks
and one antiquark, became questionable, because the candidates, i.e. the
$\Theta^+$ peak, are seen in certain reactions, i.e. p+p collisions, but not in
others, i.e. $\ee$ annihilations. In this paper, we estimate the production of
$\Theta ^{+}(1540)$ and $\Xi^{--} (1860)$ in $\ee$ annihilations at different
energies using Fermi statistical model as originally proposed in its
microcanonical form. The results is compared with that from pp collisions at
SPS and RHIC energies. We find that, if pentaquark states exist, the production
is highly possible in $\ee$ annihilations. For example, at LEP energy
$\sqrt{s}$=91.2 GeV, both $\Theta ^{+}(1540)$ and $\Xi^{--} (1860)$ yield more
than in pp collisions at SPS and RHIC energy.


title:
Fractional momentum correlations in multiple production of W bosons and
  of b-anti_b pairs in high energy pp collisions

abstract:
  Multiple parton collisions will represent a rather common feature in pp
collisions at the LHC, where regimes with very large momentum transfer may be
studied and events rare in lower energy accelerators might occur with a
significant rate. A reason of interest in large p_t regimes is that,
differently from low p_t, evolution will induce correlations in x in the
multiparton structure functions. We have estimated the cross section of
multiple production of W bosons with equal sign, where the correlations in x
induced by evolution are particularly relevant, and the cross section of
b-bar_b b-bar_b production, where the effects of evolution are much smaller.
Our result is that, in the case of multiple production of W bosons, the terms
with correlations may represent a correction of the order of 40% of the cross
sections, for pp collisions at 1 TeV c.m. energy, and a correction of the order
of 20% at 14 TeV. In the case of b-bar_b pairs the correction terms are of the
order of 10-15% at 1 TeV and of the order of 5% at 14 TeV.


title: A practical criterion of irreducibility of multi--loop Feynman integrals

abstract:
  A practical criterion for the irreducibility (with respect to integration by
part identities) of a particular Feynman integral to a given set of integrals
is presented. The irreducibility is shown to be related to the existence of
stable (with zero gradient) points of a specially constructed polynomial.


title:
A Model for Quark-Gluon Plasma with Pentaquark Baryons and Tetraquark
  Mesons

abstract:
  With a view to exploring a new kind of phase transition in the process of
hadronization of quark-gluon plasma (QGP) we investigate the occurrence of
pentaquark baryons and tetraquark mesons in the system. For this purpose, the
frame work of an analoguous Saha's ionization formula for the colored ions in
the system is used. The study of color-ionic-fraction (CIF) of multiply (color)
ionized to unionized quark clusters (termed as "quarkons") as a function of
temperature is carried out. It is pointed out that not only the temperature of
the fire-ball in the relativistic heavy ion collisions evolves with respect to
space and time but also the CIF associated with a particular stage of
ionization. Further, for the case of single color-ionization a correspondence
of the present results with those available for the bubble nucleation mechanism
in QGP is demonstrated.


title: Sfermion decays into singlets and singlinos in the NMSSM

abstract:
  We investigate how the addition of the singlet Higgs field in the NMSSM
changes the sfermion branching ratios as compared to the MSSM. We concentrate
in particular on the third generation, discussing decays of the heavier stop,
sbottom or stau into the lighter mass eigenstate plus a scalar or pseudoscalar
singlet Higgs. We also analyse stop, sbottom and stau decays into singlinos. It
turns out that the branching ratios of these decays can be large, markedly
influencing the sfermion phenomenology in the NMSSM. Moreover, we consider
decays of first and second generation sfermions into singlinos.


title: Effective field theories

abstract:
  Draft version of an article prepared for the Encyclopedia of Mathematical
Physics, Elsevier, to appear in 2006.


title:
Influence of a dynamical gluon mass in the $pp$ and $\bar{p}p$ forward
  scattering

abstract:
  We compute the tree level cross section for gluon-gluon elastic scattering
taking into account a dynamical gluon mass, and show that this mass scale is a
natural regulator for this subprocess cross section. Using an eikonal approach
in order to examine the relationship between this gluon-gluon scattering and
the elastic $pp$ and $\bar{p}p$ channels, we found that the dynamical gluon
mass is of the same order of magnitude as the {\it ad hoc} infrared mass scale
$m_{0}$ underlying eikonalized QCD-inspired models. We argue that this
correspondence is not an accidental result, and that this dynamical scale
indeed represents the onset of non-perturbative contributions to the elastic
hadron-hadron scattering. We apply the eikonal model with a dynamical infrared
mass scale to obtain predictions for $\sigma_{tot}^{pp,\bar{p}p}$,
$\rho^{pp,\bar{p}p}$, slope $B^{pp,\bar{p}p}$, and differential elastic
scattering cross section $d\sigma^{\bar{p}p}/dt$ at Tevatron and CERN-LHC
energies.


title: Dalitz Plots and Hadron Spectroscopy

abstract:
  In this master thesis I discuss how the weak three-body decay B^+ --> pi^-
pi^+ K^+ is related to the strong interactions between the final-state
particles. Current issues in hadron spectroscopy define a region of interest in
a Dalitz plot of this decay. This region is roughly characterized by energies
from 0 to 1.6 GeV of the pi^- pi^+ and the pi^- K^+ system, and energies from 3
to 5 GeV of the pi^+ K^+ system. Therefore I propose to use for the former two
systems elastic unitarity (Watson's theorem) as an approximate ansatz, and a
non-vanishing forward-peaked amplitude for the latter system. I introduce most
basic concepts in detail with the intention that this be of use to non-experts
interested in this topic.


title:
Single--Spin Asymmetries in the Bethe--Heitler Process $e^- + p \to e^-
  + \gamma + p$ from QED Radiative Corrections

abstract:
  We derived analytic formulae for the polarization single--spin asymmetries
(SSA) in the Bethe--Heitler process $e^- + p \to e^- + \gamma + p$. The
asymmetries arise due to one-loop QED radiative corrections to the leptonic
part of the interaction and present a systematic correction for the studies of
virtual Compton Scattering on a proton through interference with the
Bethe-Heitler amplitude. Considered are SSA with either longitudinally
polarized electron beam or a polarized proton target. The computed effect
appears to be small, not exceeding 0.1 per cent for kinematics of current
virtual Compton scattering experiments.


title: New contributions to heavy-quarkonium production

abstract:
  We reconsider quarkonium production in a field-theoretical setting and we
show that the lowest-order mechanism for heavy-quarkonium production receives
in general contributions from two different cuts. The first one corresponds to
the usual colour-singlet mechanism. The second one has not been considered so
far. We treat it in a gauge-invariant manner, and introduce new 4-point
vertices, suggestive of the colour-octet mechanism. These new objects enable us
to go beyond the static approximation. We show that the contribution of the new
cut can be as large as the usual colour-singlet mechanism at high transverse
momentum for J/psi. In the psi' case, theoretical uncertainties are shown to be
large and agreement with data is possible.


title: Two-Loop Quark and Gluon Form Factors in Dimensional Regularisation

abstract:
  We compute the two-loop corrections to the massless quark form factor
$\gamma^* \to q\bar q$ and gluon form factor $H\to gg$ to all orders in the
dimensional regularisation parameter $\epsilon=(4-d)/2$. The two-loop
contributions to the form factors are reduced to linear combinations of master
integrals, which are computed in a closed form, expressed as $\Gamma$-functions
and generalised hypergeometric functions of unit argument. Using the newly
developed HypExp-package, these can be expanded to any desired order, yielding
Laurent expansions in $\epsilon$. We provide expansions of the form factors to
order $\epsilon^2$, as required for ultraviolet renormalisation and infrared
factorisation of the three-loop form factors.


title: Four Quark Interpretation of Y(4260)

abstract:
  We propose that the Y(4260) particle recently announced by BaBar is the first
orbital excitation of a diquark-antidiquark state ([cs][cbar sbar]). Using
parameters recently determined to describe the X(3872) and X(3940) we show that
the Y mass is compatible with the orbital excitation picture. A crucial
prediction is that Y(4260) should decay predominantly in D_s D_sbar. The
Y(4260) should also be seen in B non-leptonic decays in association with one
kaon. We consider the full nonet of related four-quark states and their
predicted properties. Finally, we comment on a possible narrow resonance in the
same channel.


title:
String-Inspired Triplet See-Saw from Diagonal Embedding of SU(2)_L in
  SU(2)_A x SU(2)_B

abstract:
  Motivated by string constructions, we consider a variant on the Type II
see-saw mechanism involving the exchange of triplet representations of SU(2)_L
in which this group arises from a diagonal embedding into SU(2)_A x SU(2)_B. A
natural assignment of Standard Model lepton doublets to the two underlying
gauge groups results in a bimaximal pattern of neutrino mixings and an inverted
hierarchy in masses. Simple perturbations around this leading-order structure
can accommodate the observed pattern of neutrino masses and mixings.


title: Recent Developments in Perturbative QCD

abstract:
  I review recent progress in perturbative QCD on two fronts: extending
next-to-next-to-leading order QCD corrections to a broader range of collider
processes, and applying twistor-space methods (and related spinoffs) to
computations of multi-parton scattering amplitudes.


title: Radiative Generation of Leptonic CP Violation

abstract:
  Three CP-violating phases of the $3\times 3$ lepton flavor mixing matrix $V$
are entangled with one another in the renormalization-group evolution from the
seesaw scale ($\Lambda_{\rm SS} \sim 10^{14}$ GeV) to the electroweak scale
($\Lambda_{\rm EW} \sim 10^2$ GeV). Concerning the Dirac phase $\delta$, we
show that $\delta =90^\circ$ at $\Lambda_{\rm EW}$ can be radiatively generated
from $\delta =0^\circ$ at $\Lambda_{\rm SS}$ in the minimal supersymmetric
standard model, if three neutrino masses are nearly degenerate. As for the
Majorana phases $\rho$ and $\sigma$, it is also possible to radiatively
generate $\rho =90^\circ$ or $\sigma = 90^\circ$ at $\Lambda_{\rm EW}$ from
$\rho =0^\circ$ or $\sigma = 0^\circ$ at $\Lambda_{\rm SS}$. The one-loop
renormalization-group equations for the Jarlskog invariant and two off-diagonal
asymmetries of $V$ are derived, and their running behaviors from $\Lambda_{\rm
SS}$ to $\Lambda_{\rm EW}$ are numerically illustrated.


title: Dark matter clues in the muon anomalous magnetic moment

abstract:
  We study the possibility to explain the non-baryonic dark matter abundance
and improve the present fits on the muon anomalous magnetic moment through the
same new physics. The only viable way to solve simultaneously both problems
which is known to date is by using supersymmetric theories. However in this
work we show that massive brane fluctuations (branons) in large
extra-dimensions models can provide a more economical alternative to
supersymmetry. This is so because the low-energy branon physics depends
effectively on only three parameters. Next collider experiments, such as LHC or
ILC, will be sensitive to branon phenomenology in the natural parameter region
where the theory is able to account for the two effects.


title: A Prediction from the Type III See-saw Mechanism

abstract:
  A simple ansatz that is well-motivated by group-theoretical considerations is
proposed in the context of the type III neutrino see-saw mechanism. It results
in predictions for m_s/m_b and m_b/m_tau that relate these quantities to the
masses and mixings of neutrinos.


title: Hadroproduction of D and B mesons in a massive VFNS

abstract:
  We present a calculation of the next-to-leading order cross section for the
inclusive hadroproduction of D and B mesons as a function of the transverse
momentum and the rapidity in a massive variable flavor number scheme. We
compare our numerical results with recent data from the CDF Collaboration at
the Fermilab Tevatron for the production of D^0, D^{*+}, D^+, and D_s^+ mesons
at center-of-mass energy $\sqrt{S} = 1.96$ TeV and find reasonably good
agreement with the measured cross sections.


title:
Standard-model-like Higgs boson production at the CERN LHC in 3-3-1
  model with right-handed neutrinos

abstract:
  The models based on ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_X$ gauge group
(3-3-1) contain new Higgs bosons and one of them is the SM-like Higgs boson
$h$. Production of this Higgs boson at $p p$ colliders in the framework of
3-3-1 model with right-handed neutrinos is calculated. We found that the
contribution of the real $Z^\prime$ to the process $pp\to hZ$ is nearly 60 fb
if $M_{Z^\prime}$ is about 1 TeV. The decay width and the branching ratios of
the $Z'$ extra neutral gauge boson are systematically discussed.


title: Yukawa enhanced electroweak corrections at high energy in the MSSM

abstract:
  We consider the electroweak radiative corrections in the MSSM and study the
purely Yukawa contributions ${\cal O}(\alpha^L y_t^{2p} y_b^{2q})$, $p+q=L$,
where $y_{t,b}$ are the top and bottom quark Yukawa couplings. We show that
these corrections can be computed in a gaugeless limit of the MSSM where they
are under Renormalization Group control. As an application, we present explicit
results for various ILC and LHC processes valid at all orders in the loop
expansion and at leading order in the large logarithms that arise at high
energy.


title: Coupled-channel study of crypto-exotic baryons with charm

abstract:
  Identifying the t-channel exchange of vector mesons as the driving force for
the s-wave scattering of pseudo-scalar mesons off the baryon ground states, a
surprisingly 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. All channels that are required by the existence
of (u,d,s,c) quarks are considered. A bound state with exotic quantum numbers
is predicted at mass 2.78 GeV. It couples strongly to the (bar D_s N),(bar D
Lambda),(bar D Sigma) channels. A further charm minus-one system is predicted
at mass 2.84 GeV as a result of (bar D_s Lambda), (bar D Xi) interactions. 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 two so far observed
s-wave baryons with charm one are recovered. We argue that the Lambda_c(2880)
is not a s-wave state. In addition to those states we predict the existence of
about ten narrow s-wave baryon states with masses below 3 GeV.


title: Gaps between Jets: Matching two Approaches

abstract:
  We calculate the parton level cross section for the production of two jets
that are far apart in rapidity, subject to a limitation on the total transverse
momentum Q_0 in the interjet region. We specifically address the question of
how to combine the approach which sums all leading logarithms in Q/Q_0 (where Q
is the jet transverse momentum) with the BFKL approach, in which leading
logarithms of the scattering energy are summed. Using an "all orders" matching,
we obtain results for the cross section which correctly reproduce the two
approaches in the appropriate limits.


title: Non-Diagonal and Mixed Squark Production at Hadron Colliders

abstract:
  We calculate squared helicity amplitudes for non-diagonal and mixed squark
pair production at hadron colliders, taking into account not only loop-induced
QCD diagrams, but also previously unconsidered electroweak channels, which turn
out to be dominant. Mixing effects are included for both top and bottom
squarks. Numerical results are presented for several SUSY benchmark scenarios
at both the CERN LHC and the Fermilab Tevatron, including the possibilities of
light stops or sbottoms. The latter should be easily observed at the Tevatron
in associated production of stops and sbottoms for a large range of stop masses
and almost independently of the stop mixing angle. Asymmetry measurements for
light stops at the polarized BNL RHIC collider are also briefly discussed.


title: A Criterion of Naturalness in Renormalization

abstract:
  The sensitivity criterion is widely used in measuring the level of
fine-tuning, although many examples show it doesn't work under certain
circumstances. We discuss the mathematics behind the fine-tuning problems,
explain the mathematical meanings of the sensitivity criterion, point out three
implicit assumptions behind this criterion. Because of these assumptions, the
sensitivity criterion can't reflect the fine-tuning level correctly. By
analyzing two well known examples that the sensitivity criterion failed, we
point out the dimensional effect is the main reason why we have these problems.
To solve these problems, we proposed a new criterion to replace the sensitivity
criterion.


title: Flow dependence of high $p_T$ parton energy loss in heavy-ion collisions

abstract:
  The measured transverse momentum spectra and HBT correlations of bulk (i.e.
low $p_T$) matter can be well explained by assuming that the soft sector of
particles produced in ultrarelativistic heavy-ion collisions is (approximately)
thermalized and undergoes collective accelerated expansion in both longitudinal
and transverse direction. However, this implies that bulk matter will have a
non-vanishing flow component transverse to the trajectory of a high $p_T$
partonic jets. In general, this will increase the energy loss experienced by
the jet parton and modify the shape of the jet cone. In this paper, we present
a systematic study of the magnitude of the additional energy loss induced by
flow under realistic assumptions for the medium evolution. We argue that a
perturbative QGP description may be sufficient for the measured $R_{AA}$ if
flow during the medium evolution is taken into account properly.


title:
|V_ub| and Constraints on the Leading-Twist Pion Distribution Amplitude
  from B->pi l nu

abstract:
  Using new experimental data on the leptonic mass spectrum of B->pi l nu, we
simultaneously determine |V_ub| and constrain a_2^pi and a_4^pi, the first two
Gegenbauer moments of the pion's leading-twist distribution amplitude. We find
|V_ub| = (3.2\pm 0.1\pm 0.1\pm 0.3) 10^-3, where the first error is
experimental, the second comes from the shape of the form factor in q^2 and the
third is a 8% uncertainty from the normalisation of the form factor. We also
find a_2^pi(1 GeV)=0.19\pm 0.19 and a_4^pi(1 GeV)\geq -0.07.


title: Development of Chaos in the Color Glass Condensate

abstract:
  Noting that the number of gluons in the hadron wave function is discrete, and
their formation in the chain of small-x evolution occurs over discrete rapidity
intervals of Delta y~1/alpha_s, we formulate the discrete version of the
Balitsky--Kovchegov evolution equation and show that its solution behaves
chaotically in the phenomenologically interesting kinematic region.


title: The Physics of Hadronic Tau Decays

abstract:
  Hadronic tau decays represent a clean laboratory for the precise study of
quantum chromodynamics (QCD). Observables (sum rules) based on the spectral
functions of hadronic tau decays can be related to QCD quark-level calculations
to determine fundamental quantities like the strong coupling constant,
parameters of the chiral Lagrangian, |V_us|, the mass of the strange quark, and
to simultaneously test the concept of quark-hadron duality. Using the best
available measurements and a revisited analysis of the theoretical framework,
the value alpha_s(m_tau) = 0.345 +- 0.004[exp] +- 0.009[theo] is obtained.
Taken together with the determination of alpha_s(m_Z) from the global
electroweak fit, this result leads to the most accurate test of asymptotic
freedom: the value of the logarithmic slope of 1/alpha_s(s) is found to agree
with QCD at a precision of 4%. In another approach, the tau spectral functions
can be used to determine hadronic quantities that, due to the nonperturbative
nature of long-distance QCD, cannot be computed from first principles. An
example for this is the contribution from hadronic vacuum polarization to
loop-dominated processes like the anomalous magnetic moment of the muon. This
article reviews the measurements of nonstrange and strange tau spectral
functions and their phenomenological applications.


title:
Effects of density-dependent quark mass on phase diagram of three-flavor
  quark matter

abstract:
  Considering the density dependence of quark mass, we investigate the phase
transition between the (unpaired) strange quark matter and the
color-flavor-locked matter, which are supposed to be two candidates for the
ground state of strongly interacting matter. We find that if the current mass
of strange quark $m_s$ is small, the strange quark matter remains stable unless
the baryon density is very high. If $m_s$ is large, the phase transition from
the strange quark matter to the color-flavor-locked matter in particular to its
gapless phase is found to be different from the results predicted by previous
works. A complicated phase diagram of three-flavor quark matter is presented,
in which the color-flavor-locked phase region is suppressed for moderate
densities.


title:
Package for Calculations and Simplifications of Expressions with Dirac
  Matrixes (MatrixExp)

abstract:
  This paper describes a package for calculations of expressions with Dirac
matrixes. Advantages to existing similar packages are described. MatrixExp
package is intended for simplification of complex expressions involving
$\gamma$-matrixes, providing such tools as automatic Feynman parameterization,
integration in $d$-dimensional space, sorting and grouping of results in a
given order. Also, in comparison with existing similar package Tracer,
presented package MatrixExp has more enhanced input possibility. User-available
functions of MatrixExp package are described in detail. Also an example of
calculation of Feynman diagram for process $b\to s\gamma g$ with application of
functions of MatrixExp package is presented.


title: Pseudo-Axions in Little Higgs Models

abstract:
  In Little Higgs models, the Higgs mass is stabilized at the one-loop level by
the mechanism of collective symmetry breaking. Typically, the basic ingredient
of these models is a large(r) global symmetry group spontaneously broken at a
scale of several TeV. The (light) Higgs appears as a Goldstone boson
corresponding to a non-diagonal broken generator of this global symmetry. There
could also be physical pseudoscalar particles present which belong to diagonal
generators, having the properties of axions with masses in the range from
several GeV up to the electroweak scale. We investigate the interesting
phenomenology of these pseudo-axions at the linear collider as well as the
photon collider.


title:
Global fits to the Cabibbo-Kobayashi-Maskawa matrix: unitarity condition
  method versus standard unitarity triangles approach

abstract:
  The aim of the paper is to make a comparison between the unitarity condition
method and the standard version of the unitarity triangle approach by using as
parameters four independent moduli $|U_{ij}|$. This choice is motivated by the
measurability property and leads to a simple criterion for the separation of
unistochastic matrices from the double stochastic ones, whose fulfillment is
the key point of any global fit for the CKM entries. In our formulation both
the methods are exact, do not depend on any assumption as the smallness of some
parameter and both can be used to global fits in the quark and fermion sectors.
Monte Carlo simulations show that the separation criterion puts very strong
conditions requiring a fine tuning of all the CKM matrix elements.


title:
GMSB SUSY models with non pointing photons signatures in ATLAS at the
  LHC

abstract:
  The reconstruction of non pointing photons is a key feature for studying
gauge mediated supersymmetry breaking (GMSB) models at the LHC. In this article
the angular resolution of the ATLAS electromagnetic calorimeter is
characterized from a detailed simulation of the detector. Resulting
performances are used to reconstruct GMSB events with a fast simulation
program, taking into account reconstruction effects. Finally, the sensitivity
to extract the sparticles masses and the lightest neutralino lifetime is
estimated.


title: Heavy quark bound states above $T_c$

abstract:
  A comprehensive parameterization of the colour singlet heavy quark free
energy above $T_c$ is given, using the lattice data in quenched ($N_f=0$) and
unquenched ($N_f=2$ and $N_f=3$) QCD. The corresponding (temperature dependent)
potentials thus obtained are then inserted into the Schr\"odinger equation for
the charmonium and the bottomonium in the deconfined phase of QCD. The solution
of the equation provides an estimate of the melting temperature and of the
radii for the different $c\bar{c}$ and $b\bar{b}$ bound states.


title:
A description of the ratio between electric and magnetic proton form
  factors by using space-like, time-like data and dispersion relations

abstract:
  We use the available information on the ratio between the electric and
magnetic proton form factors coming from recently published space-like data and
from the few available time-like data. We apply a dispersive procedure on these
data to evaluate the behaviour of this ratio, as a complex function, for all
values of q^2.


title: Antiproton fluxes from light neutralinos

abstract:
  We analyze how the measurements of the low-energy spectrum of cosmic
antiprotons can provide information on relic neutralinos. The analysis is
focused on the light neutralinos which emerge in supersymmetric schemes where
gaugino-mass unification is not assumed. We determine which ranges of the
astrophysical parameters already imply stringent constraints on the
supersymmetric configurations and those ranges which make the antiproton flux
sensitive to the primary component generated by the neutralino
self-annihilation. Our results are derived from some general properties of the
antiproton flux proved to be valid for a generic cold dark matter candidate.


title: Tera-Leptons Shadows over Sinister Universe

abstract:
  The role of Sinister Heavy Fermions in recent Glashow's
SU(3)*SU(2)*SU(2)'*U(1) model is to offer in a unique frame relic Helium-like
products (an ingenious candidate to the dark matter puzzle), a solution to the
See-Saw mechanism for light neutrino masses as well as to strong CP violation
problem in QCD. The Sinister model requires a three additional families of
leptons and quarks, but only the lightest of them Heavy U-quark and
E-"electron" are stable. Final neutral Helium-like UUUEE state is an ideal
evanescent dark-matter candidate. However it is reached by multi-body
interactions along a tail of more manifest secondary frozen blocks. They should
be now here polluting the surrounding matter. Moreover, in opposition to
effective pair quark annihilations, there is no such an early or late
tera-lepton pairs suppressions, because:a) electromagnetic interactions are
"weaker" than nuclear ones and b) helium ion 4He++ is able to attract and
capture, E-, fixing it into a hybrid tera helium "ion" trap. This leads to a
pile up of relic (4HeE)+ traces, a lethal compound for any Sinister Universe.
This capture leaves no Tera-Lepton frozen in Ep relic (otherwise an ideal
catalyzer to achieve effective late E+E- annihilations possibly saving the
model). The (4HeE)+ Coulomb screening is also avoiding the synthesis of the
desired UUUEE hidden dark matter gas. The e(4HeE)+ behave chemically like an
anomalous hydrogen isotope.Also tera-positronium (eE+) relics are over-abundant
and they behave like an anomalous hydrogen atom: these gases do not fit by many
orders of magnitude known severe bounds on hydrogen anomalous isotope, making
grave shadows over a Sinister Universe. However a surprising and resolver role
for Tera-Pions in UHECR astrophysics has been revealed.


title: Inequalities between quark densities

abstract:
  We propose an inequality between the longitudinally polarized density and the
transversity of a quark in a nucleon. This inequality, whose validity is
limited to very small scales, is based on considerations about Lorentz
transformations and on commonly accepted models. Therefore it may be used as a
consistecy check with other models. It turns out to agree with most model
preedictions. Moreover it allows to establish, thanks to the positivity
constraint, another inequality between the longitudinally polarized and the
unpolarized valence quark density. We show that this latter inequality may be
extended to any Q^2, consistently with commonly used factorization schemes and
with some nonperturbative evolution models. This inequality finds nontrivial
applications to the valence "d"-quark densities and is compared with data
analyses, with model predictions and with parametrizations of quark densities.


title:
On the increase with relative distances of light cone operator product
  of currents and related phenomena

abstract:
  We show that in QCD in the leading twist approximation flavor singlet light
cone current-current correlators increase with distances rapidly similar to the
correlator of velocities in turbulence and argue that this property is
precursor of phase transitions in high energy processes . It is shown that
absence of spatial oscillations of current-current correlators follows from
asymptotic freedom in QCD. We discuss also influence of this new long-range
interaction on the wave function of dipole in high energy DIS processes near
the black disc limit.


title: The Pomeron structure and diffractive parton distributions

abstract:
  Measurements of the diffractive structure function, $F_2^D$, of the proton at
HERA are used to extract the partonic structure of the Pomeron. Regge
Factorization is tested and is found to describe well the existing data within
the selected kinematic range. The analysis is based on the next to leading
order QCD evolution equations. The results obtained from various data sets are
compared. An analysis of the uncertainties in determining the parton
distributions is provided. The probability of diffraction is calculated using
the obtained results.


title: NLO photon parton parametrization

abstract:
  An NLO photon parton parametrization is presented based on the existing
$F_2^\gamma$ measurements from $e^+e^-$ data and the low-$x$ proton structure
function from $ep$ interactions. Also included in the extraction of the NLO
parton distribution functions are the dijets data coming from $\gamma p \to j_1
+ j_2 +X$. The new parametrization is compared to other available NLO
parametrizations.


title: Enlarging the window for radiative leptogenesis

abstract:
  We investigate the scenario of resonant thermal leptogenesis, in which the
leptonic asymmetries are generated through renormalization group corrections
induced at the leptogenesis scale. In the framework of the standard model
extended by three right-handed heavy Majorana neutrinos with masses M1 = M2 <<
M3 at some high scale, we show that the mass splitting and CP-violating effects
induced by renormalization group corrections can lead to values of the CP
asymmetries large enough for a successful leptogenesis. In this scenario, the
low-energy neutrino oscillation data can also be easily accommodated. The
possibility of having an underlying symmetry behind the degeneracy in the
right-handed neutrino mass spectrum is also discussed.


title: Parton Distributions

abstract:
  I present an overview of some current topics in the measurement of Parton
Distribution Functions.


title:
HypExp, a Mathematica package for expanding hypergeometric functions
  around integer-valued parameters

abstract:
  We present the Mathematica package HypExp which allows to expand
hypergeometric functions $_JF_{J-1}$ around integer parameters to arbitrary
order. At this, we apply two methods, the first one being based on an integral
representation, the second one on the nested sums approach. The expansion works
for both symbolic argument $z$ and unit argument. We also implemented new
classes of integrals that appear in the first method and that are, in part, yet
unknown to Mathematica.


title: Shadowing and Antishadowing in Neutrino Deep Inelastic Scattering

abstract:
  The coherence of multiscattering quark nuclear processes leads to shadowing
and antishadowing of the electromagnetic nuclear structure functions in
agreement with measurements. This picture leads to substantially different
antishadowing for charged and neutral current processes, particularly in
anti-neutrino reactions, thus affecting the extraction of the weak-mixing angle
$\sin^2\theta_W$.


title: Equation of state and Beginning of Thermalization After Preheating

abstract:
  We study the out-of-equilibrium nonlinear dynamics of fields after
post-inflationary preheating. During preheating, the energy in the homogeneous
inflaton is exponentially rapidly transfered into highly occupied
out-of-equilibrium inhomogeneous modes, which subsequently evolve towards
equilibrium. The infrared modes excited during preheating evolve towards a
saturated distribution long before thermalization completes. We compute the
equation of state during and immediately after preheating. It rapidly evolves
towards radiation domination long before the actual thermal equilibrium is
established. The exact time of this transition is a non-monotonic function of
the coupling between the inflaton and the decay products, and it varies only
very weakly (around 10^(-35) s) as this coupling changes over several orders of
magnitude. This result is applied to refine the relation between the number of
efoldings N and the physical wavelength of perturbations generated during
inflation. We also discuss the implications for the theory of modulated
perturbations from preheating. We finally argue that many questions of the
thermal history of the universe should be addressed in terms of
pre-thermalization, illustrating this point with a calculation of perturbative
production of gravitinos immediately after chaotic inflation. We also highlight
the effects of three-legs inflaton interactions on the dynamics of preheating
and thermalization in an expanding universe.


title: The clash of symmetries in a Randall-Sundrum-like spacetime

abstract:
  We present a toy model that exhibits clash-of-symmetries style Higgs field
kink configurations in a Randall-Sundrum-like spacetime. The model has two
complex scalar fields Phi_{1,2}, with a sextic potential obeying global
U(1)xU(1) and discrete Phi_1 <--> Phi_2 interchange symmetries. The scalar
fields are coupled to 4+1 dimensional gravity endowed with a bulk cosmological
constant. We show that the coupled Einstein-Higgs field equations have an
interesting analytic solution provided the sextic potential adopts a particular
form. The 4+1 metric is shown to be that of a smoothed-out Randall-Sundrum type
of spacetime. The thin-brane Randall-Sundrum limit, whereby the Higgs field
kinks become step functions, is carefully defined in terms of the fundamental
parameters in the action. The ``clash of symmetries'' feature, defined in
previous papers, is manifested here through the fact that both of the U(1)
symmetries are spontaneously broken at all non-asymptotic points in the extra
dimension $w$. One of the U(1)'s is asymptotically restored as w --> -infinity,
with the other U(1) restored as w --> +infinity. The spontaneously broken
discrete symmetry ensures topological stability. In the gauged version of this
model we find new flat-space solutions, but in the warped metric case we have
been unable to find any solutions with nonzero gauge fields.


title:
J/Psi photo- and electroproduction, the saturation scale and the gluon
  structure function

abstract:
  Our approach to low-x deep inelastic scattering based on the ell-perp
factorization of perturbative QCD (the color-dipole picture) yields
parameter-free absolute predictions for J/Psi production. The connection of
J/Psi production to the low-x saturation scale and to the gluon structure
function is clarified.


title: Resonances and Electroweak Observables at the ILC

abstract:
  Precise measurements of the interactions of electroweak vector bosons at the
ILC yield information about the physics of electroweak symmetry breaking. In
order to combine this with the possible observation of new resonances or the
effects of new strong interactions at the LHC, we need to relate resonance
parameters with low-energy observables. We derive these relations for a generic
setup and draw conclusions about the new-physics reach of the ILC in the
electroweak sector.


title:
Impact of tau polarization on the study of the MSSM charged Higgs bosons
  in top quark decays at the ILC

abstract:
  The process of top quark pair production at the ILC with subsequent decays of
one of the top quarks to a charged Higgs boson and b-quark is considered. The
charged Higgs decays to tau leptons whose polarization is the opposite to those
coming from W bosons. This difference is reflected in the energy distributions
of the tau decay products in the top quark rest frame, which can be
reconstructed at the ILC using the recoil mass technique. We present an
analysis including spin correlations, backgrounds, ISR/FSR and beamstrahlung,
and show that a fit of the shape of the pion energy spectrum yields the charged
Higgs boson mass with an accuracy of about 1 GeV.


title:
NLO BFKL tests using the proton structure function $F_2$ measured at
  HERA

abstract:
  We propose a phenomenological study of the next-to-leading
Balitsky-Fadin-Kuraev-Lipatov (BFKL) approach applied to the data on the proton
structure function $F_2$ measured at HERA in the small-$x_{Bj}$ region.


title: High mass diffraction at the LHC

abstract:
  We use a Monte Carlo implementation of recently developped models of
exclusive diffractive W, top, Higgs and stop productions to assess the
sensitivity of the LHC experiments.


title: Dynamics of massive matter disappearance on the brane

abstract:
  Time evolution of the probability of quasilocalized massive modes decay
trough the tunneling into an extra dimension is analyzed in the Randall-Sundrum
braneworld model.


title: The Infrared Behaviour of the Pure Yang-Mills Green Functions

abstract:
  We study the infrared behaviour of the pure Yang-Mills correlators using
relations that are well defined in the non-perturbative domain. These are the
Slavnov-Taylor identity for three-gluon vertex and the Schwinger-Dyson equation
for ghost propagator in the Landau gauge. We also use several inputs from
lattice simulations. We show that lattice data are in serious conflict with a
widely spread analytical relation between the gluon and ghost infrared critical
exponents. We conjecture that this is explained by a singular behaviour of the
ghost-ghost-gluon vertex function in the infrared. We show that, anyhow, this
discrepancy is not due to some lattice artefact since lattice Green functions
satisfy the ghost propagator Schwinger-Dyson equation. We also report on a
puzzle concerning the infrared gluon propagator: lattice data seem to favor a
constant non vanishing zero momentum gluon propagator, while the Slavnov-Taylor
identity (complemented with some regularity hypothesis of scalar functions)
implies that it should diverge.


title:
Five-body calculation of resonance and scattering states of pentaquark
  system

abstract:
  Scattering problem of the $uudd{\bar s}$ system, in the standard
non-relativistic quark model of Isgur-Karl, is solved for the first time, by
treating the large five-body modelspace including the $NK$ scattering channel
accurately with the Gaussian expansion method and the Kohn-type coupled-channel
variational method. The two-body interaction that reproduces observed
properties of ordinary baryons and mesons is applied to the pentaquark system
with no additional adjustable parameter. The five-body wave function calculated
has the correct asymptotic form in its the scattering-channel component and
describes $qq$ and $q{\bar q}$ correlations properly. The $NK$ scattering phase
shift calculated shows no resonance in the energy region of the reported
pentaquark $\Theta^+(1540)$, that is, at 0-500 MeV above the $NK$ threshold
($1.4-1.9$ GeV in mass). The phase shift does show two resonances just above
500 MeV: a broad ${1/2}^+$ resonance with a width of $ \Gamma \sim~110$ MeV
located at $\sim~520$ MeV ($\sim~2.0$ GeV in mass) and a sharp ${1/2}^-$
resonance with $\Gamma=$0.12 MeV at 540 MeV. Properties of these states are
discussed.


title:
Dimensional Regularisation and Factorisation Schemes in the BFKL
  Equation at Subleading Leve

abstract:
  We study the anomalous dimensions and coefficient functions generated by the
BFKL equation in 4+2 epsilon dimensions, by investigating both running coupling
effects, and the inclusion of the full next-to-leading kernel. After
generalising the Fourier representation of the solutions to this case, we
analyse the beta-dependent renormalisation-group factorisation of anomalous
dimension and coefficient contributions to the gluon density. We derive on this
basis the normalisation factor of the Q0-scheme with respect to the
MSbar-scheme, including beta-dependent corrections to it, and we outline the
derivation of the full next-to-leading contributions. We also provide an
expression for the resummed gamma_qg in the MSbar-scheme which exhibits its
universality and is explicit up to quadratures.


title: Semi-inclusive radiative decays of Upsilon 1S

abstract:
  We discuss in detail the photon spectrum of radiative Upsilon 1S decays
taking into account a number of results that have recently appeared in the
literature. In particular, we show how to consistently combine expressions
which are valid in the upper end-point region, where NRQCD factorization breaks
down, with those of the central region, where NRQCD factorization holds. An
excellent description of data is achieved, but theoretical errors are large.


title: Small-x effects in forward-jet production at HERA

abstract:
  We investigate small-x effects in forward-jet production at HERA in the
two-hard-scale region kT ~ Q>>Lambda_QCD. We show that, despite describing
different energy regimes, both a BFKL parametrization and saturation
parametrizations describe well the H1 and ZEUS data for dsigma/dx published a
few years ago. This is confirmed when comparing the predictions to the latest
data.


title:
Precision radiative corrections to the Dalitz plot of baryon
  semileptonic decays including the spin-momentum correlation of the decaying
  baryon and the emitted charged lepton

abstract:
  We calculate the radiative corrections to the angular correlation between the
polarization of the decaying baryon and the direction of the emitted charged
lepton in the semileptonic decays of spin one-half baryons to order
(\alpha/\pi)(q/M_1). The final results are presented, first, with the triple
integration of the bremsstrahlung photon ready to be performed numerically and,
second, in an analytical form. A third presentation of our results in the form
of numerical arrays of coefficients to be multiplied on the quadratic products
of form factors is discussed. This latter may be the most practical one to use
in Monte Carlo simulations. A series of crosschecks is performed. The results
are useful in the analysis of the Dalitz plot of precision experiments
involving light and heavy quarks and is not compromised to fixing the form
factors at predetermined values. It is assumed that the real photons are
kinematically discriminated. Otherwise, our results have a general
model-independent applicability.


title: SUSY Phenomenology of KKLT Flux Compactifications

abstract:
  We study SUSY phenomenology of the KKLT (Kachru-Kallosh-Linde-Trivedi)
scenario of string theory compactifications with fluxes. This setup leads to a
specific pattern of soft masses and distinct phenomenological properties. In
particular, it avoids the cosmological gravitino/moduli problems. Remarkably,
the model allows for the correct abundance of SUSY dark matter consistently
with all experimental constraints including the bound on the Higgs mass, b-->s
gamma, etc. This occurs for both small and large tan beta, and requires the
SUSY spectrum above 1 TeV.


title:
Probing Physics in the Standard Model and Beyond with Electroweak
  Baryogenesis and Effective Theories of the Strong Interactions

abstract:
  This thesis explores two different avenues aimed at improving our ability to
calculate reliably in the Standard Model of particle physics and probing
possible new particles which may exist beyond it. In the first part, we explore
whether baryogenesis at the electroweak phase transition could successfully
account for the observed density of baryons in the Universe, using the
closed-time-path (CTP) formalism of quantum field theory to calculate the
buildup and relaxation of particle densities during the phase transition.
Adopting the MSSM for its new sources of CP violation, we look for regions of
parameter space which could give rise to sufficiently large baryon asymmetry
without violating constraints on these parameters from existing experiments,
especially searches for electric dipole moments of elementary particles. In the
second part, we explore how to get around our ignorance of the dynamics of
strongly interacting particles in the nonperturbative regime of Quantum
Chromodynamics (QCD) by the use of effective field theories. Two applications
are explored: the production of hadronic jets in Z decay or e+e- annihilation
using soft-collinear effective theory (SCET), and the radiative decays of
quarkonia to light hadrons using SCET and non-relativistic QCD (NRQCD). These
tools facilitate the proof of factorization of decay rates into
perturbatively-calculable and nonperturbative parts. Universality of the latter
among different observables provides predictive power even in our ignorance of
the details of the nonperturbative physics.


title: Non-abelian vector backgrounds with restored Lorentz invariance

abstract:
  The influence of vector backgrounds with restored Lorentz invariance on
non-abelian gauge field theories is studied. Lorentz invariance is ensured by
taking the average over a Lorentz invariant ensemble of background vectors.
Like in the abelian case [hep-ph/0506210], the propagation of fermions is
suppressed over long distances. Contrary to the fermionic sector, pure gauge
configurations of the background suppress the long-distance propagation of the
bosons only partially, i.e. not beyond the leading contribution for a large
number of colours.


title:
Hadronic production and decays of Charginos and Neutralinos in Split
  Supersymmetry

abstract:
  In the scenario recently proposed by Arkani-Hamed and Dimopoulos, the
supersymmetric scalar particles are all very heavy, at least of the order of
$10^9$ GeV but the gauginos, higgsino, and one of the CP-even neutral Higgs
bosons remain light under a TeV. In addition to gluino production, the first
SUSY signature would be pair production of neutralinos and/or charginos. Here
we study, with explicit CP violation, the production of neutralinos and
charginos at hadronic colliders as well as the possible decay modes. We notice
that the branching ratio of the neutralino radiative decay can be sizable
unlike the case with light sfermions. In particular, the decay of N3->N1+gamma
has a branching ratio of the order O(1) percent. In colliders, it would give
rise to signatures of an isolated single photon plus missing energy.


title: Nonspectator effects in B-> K^*+photon within the vector quark model

abstract:
  The tree level FCNC due to the presence of an additional generation of vector
quarks result in the leading order nonspectator contributions to rare B->
K^*+photon decay mode. These tree level contributions are sensitive only to b->
s nonunitary parameter U^{sb} and therefore, provide a direct constraint on
this model parameter. We obtain the isospin asymmetry between \bar B^0->\bar
K^{*0}+photon and B^--> K^{*-}+photon to be \Delta_{0-}=-0.03*Re
(U^{sb}/(a^c_7V_{tb}V^*_{ts})) and the direct CP asymmetry between
B^+->K^{*+}+photon and B^--> K^{*-}+photon to be
A_{CP}^{VQM}=0.27|U^{sb}/(V_{tb}V_{ts}^*)|*sin{\theta}*sin{\phi_s}, where
\theta is the weak phase of U^{sb} and \phi_s is the strong phase of decay
amplitude. We predict a direct CP asymmetry of around a few percent if the
current experimental difference between \Delta_{0-} and \Delta_{0+} is to be
explained by the presence of the additional vector quarks.


title:
Surprises from the search for quark-gluon plasma? When was quark-gluon
  plasma seen?

abstract:
  The historical context of the recent results from high energy heavy ion
reactions devoted to the search of quark-gluon plasma (QGP) is reviewed, with
emphasis on the surprises encountered. The evidence for QGP from heavy ion
reactions is compared with that available from particle reactions.


title:
Maps of zeroes of the grand canonical partition function in a
  statistical model of high energy collisions

abstract:
  Theorems on zeroes of the truncated generating function in the complex plane
are reviewed. When examined in the framework of a statistical model of high
energy collisions based on the negative binomial (Pascal) multiplicity
distribution, these results lead to maps of zeroes of the grand canonical
partition function which allow to interpret in a novel way different classes of
events in pp collisions at LHC c.m. energies.


title: Deducing Quark Rest Masses with Phenomenological Formulae

abstract:
  Using phenomenological formulae, we can deduce the rest masses and intrinsic
quantum numbers (I, S, C, B and Q) of quarks, baryons and mesons from only one
unflavored elementary quark family. The deduced quantum numbers match
experimental results exactly, and the deduced rest masses are 98.5% (or 97%)
consistent with experimental results for baryons (or mesons). This paper
predicts some quarks [d_{S}(773), d_{S}(1933) and u_{C}(6073)], baryons
[$\Lambda_{c}(6599)$, $\Lambda_{b)(9959)$] and mesons [D(6231), B(9502)]. PACS:
12.39.-x; 14.65.-q; 14.20.-c. Keywords: phenomenological, beyond the standard
model.


title: Heavy Quarkonium Production: Extending CSM and COM

abstract:
  By questioning the applicability of the static approximation of the
Colour-Singlet Model, we have seen that the production amplitude receives
contributions from two different cuts. The first one in its static limit gives
the colour-singlet mechanism. The second one has not been considered so far. We
treat it in a gauge-invariant manner by introducing necessary new 4-point
vertices, suggestive of the colour-octet mechanism. This new contribution can
be as large as the colour-singlet mechanism at high pT, however these vertices
are not totally constrained and when the freedom in their determination is
fully exploited, we are able to reproduce the production cross-sections at the
Tevatron for the J/Psi, Psi' and Upsilon(1S) and at RHIC for the J/Psi.


title: Suppressed decay into open charm for the Y(4260) being an hybrid

abstract:
  We investigate the Y(4260) resonance recently discovered by the Babar
collaboration. We propose the observation of its decay into J/psi pi pi and its
non observation into open charm as a consequence of it being a charmonium
hybrid state with a magnetic constituent gluon. We prove a selection rule
forbidding its decay into two S-wave charmed mesons in any potential model. We
suggest a generalisation of the selection rule based only on the heavy quark
nature of the charm.


title: Dynamics of Gravity in a Higgs Phase

abstract:
  We investigate the universal low-energy dynamics of the simplest Higgs phase
for gravity, `ghost condensation.' We show that the nonlinear dynamics of the
`ghostone' field dominate for all interesting gravitational sources. Away from
caustic singularities, the dynamics is equivalent to the irrotational flow of a
perfect fluid with equation of state p \propto \rho^2, where the fluid
particles can have negative mass. We argue that this theory is free from
catastrophic instabilities due to growing modes, even though the null energy
condition is violated. Numerical simulations show that solutions generally have
singularities in which negative energy regions shrink to zero size. We exhibit
partial UV completions of the theory in which these singularities are smoothly
resolved, so this does not signal any inconsistency in the effective theory. We
also consider the bounds on the symmetry breaking scale M in this theory. We
argue that the nonlinear dynamics cuts off the Jeans instability of the linear
theory, and allows M \lsim 100MeV.


title: A possible assignment for the ground scalar meson nonet

abstract:
  Based on the main assumption that the $a_0(980)$ and $D^\ast_{sJ}(2317)$
belong to the $1 ^3P_0$ $q\bar{q}$ multiplet, in the framework of Regge
phenomenology and meson-meson mixing, it is suggested that the $a_0(980)$,
$K^\ast_0(1052)$, $f_0(1099)$ and $f_0(530)$ constitute the ground scalar meson
nonet, and that the $f_0(1099)$ is composed mostly of $s\bar{s}$ while the
$f_0(530)$ is mainly $u\bar{u}+d\bar{d}$. It is supposed that these states
would likely correspond to the observed scalar states $a_0(980)$,
$\kappa(900)$,
  $f_0(980)$ and $f_0(600)/\sigma$, respectively. The agreement between the
present findings and those given by other different approaches is satisfactory.


title:
Charmless $B \to PV, VV $ decays and new physics effects in the mSUGRA
  model

abstract:
  By employing the QCD factorization approach, we calculate the new physics
contributions to the branching radios of the two-body charmless $ B \to PV$ and
$B \to VV$ decays in the framework of the minimal supergravity (mSUGRA) model.
we choose three typical sets of the mSUGRA input parameters in which the Wilson
coefficient $C_{7\gamma}(m_b)$ can be either SM-like (the case A and C) or has
a flipped-sign (the case B). We found numerically that (a) the SUSY
contributions are always very small for both case A and C; (b) for those
tree-dominated decays, the SUSY contributions in case B are also very small;
(c) for those QCD penguin-dominated decay modes, the SUSY contributions in case
B can be significant, and can provide an enhancement about $30% \sim 260%$ to
the branching ratios of $B \to K^*(\pi,\phi,\rho)$ and $K \phi$ decays, but a
reduction about $30% \sim 80%$ to $ B\to K(\rho, \omega)$ decays; and (d) the
large SUSY contributions in the case B may be masked by the large theoretical
errors dominated by the uncertainty from our ignorance of calculating the
annihilation contributions in the QCD factorization approach.


title:
Direct dark matter search by observing electrons produced in
  neutralino-nucleus collisions

abstract:
  Exotic dark matter and dark energy together seem to dominate in the Universe.
Supersymmetry naturally provides a candidate for the dark matter constituents
via the lightest supersymmetric particle (LSP). The most important process for
directly detecting dark matter is the LSP-nucleus elastic scattering by
measuring the energy of the recoiling nucleus. In the present work we explore a
novel process, which has definite experimental advantages, that is the
detection of the dark matter constituents by observing the low energy
ionization electrons. These electrons, which are produced during the
LSP-nucleus collision, may be observed separately or in coincidence with the
recoiling nuclei.
  We develop the formalism and apply it in calculating the ratio of the
ionization rate to the nuclear recoil rate in a variety of atoms including
Ne-20, Ar-40, Ge-76, Kr-78 and Xe-132 employing realistic Hartree-Fock electron
wave functions.
  The obtained ratios are essentially independent of all parameters of
supersymmetry except the neutralino mass, but they crucially depend on the
electron energy cut off. These ratios per electron tend to increase with the
atomic number and can be as high as 10 per cent. Based on our results it is
both interesting and realistic to detect the LSP by measuring the ionization
electrons following the-LSP nuclear collisions.


title: Sneutrino warm inflation in the minimal supersymmetric model

abstract:
  The model of RH neutrino fields coupled to the MSSM is shown to yield a large
parameter regime of warm inflation. In the strong dissipative regime, it is
shown that inflation, driven by a single sneutrino field, occurs with {\it all
field amplitudes below the Planck scale}. Analysis is also made of
leptogenesis, neutrino mass generation and gravitino constraints. A new warm
inflation scenario is purposed in which one scalar field drives a period of
warm inflation and a second field drives a subsequent phase of reheating. Such
a model is able to reduce the final temperature after inflation, thus helping
to mitigate gravitino constraints.


title:
Competition of Color Ferromagnetic and Superconductive States in a
  Quark-Gluon System

abstract:
  The possibility of color ferromagnetism in an SU(2) gauge field model is
investigated. The conditions allowing a stable color ferromagnetic state of the
quark system in the chromomagnetic field occupying small domains are
considered. A phase transition between this state and the color superconducting
state is considered. The effect of finite temperature is analyzed.


title:
Determining weak phase gamma and probing new physics in b->s transitions
  from B->eta(eta')K

abstract:
  We present a method of determining weak phase \gamma in the
Cabibbo-Kobayashi-Maskawa matrix from decays B->\eta K, \eta' K$ alone. Given a
large ratio between color-suppressed and color-allowed tree diagrams extracted
from global \pi\pi(K) fits, \gamma is determined from the current data of \eta'
K and the result is in agreement with the global Standard Model(SM) fits.
However, a smaller ratio from factorization based calculations gives
$\gamma\sim 90^\circ$. New physics beyond the SM can be singled out if\gamma
obtained in \eta^{(')} K modes is significantly different than the ones from
other modes or other approaches. The effective value of \gamma from \eta' K is
very sensitive to new physics contributions and can be used to extract new
physics parameters for a class of models which do not give contributions to
strong phases significantly.


title:
Self-annihilation of the neutralino dark matter into two photons or a Z
  and a photon in the MSSM

abstract:
  We revisit the one-loop calculation of the annihilation of a pair of the
lightest neutralinos into a pair of photons, a pair of gluons and also a Z
photon final state. For the latter we have identified a new contribution that
may not always be negligible. For all three processes we have conducted a tuned
comparison with previous calculations for some characteristic scenarios. The
approach to the very heavy higgsino and wino is studied and we argue how the
full one-loop calculation should be matched into a more complete treatment that
was presented recently for these extreme regimes. We also give a short
description of the code that we exploited for the automatic calculation of
one-loop cross sections in the MSSM that could apply both for observables at
the colliders and for astrophysics or relic density calculations. In particular
the automatic treatment of zero Gram determinants which appear in the latter
applications is outlined. We also point out how generalised non-linear gauge
fixing constraints can be exploited.


title: Charge breaking bounds in the Zee model

abstract:
  We study the possibility that charge breaking minima occur in the Zee model.
We reach very different conclusions from those attained in simpler, two Higgs
doublet models, and the reason for this is traced back to the existence of
cubic terms in the potential. A scan of the Zee model's parameter space shows
that CB is restricted to a narrow region of values of the parameters.


title: QCD (&) Event Generators

abstract:
  Recent developments in QCD phenomenology have spurred on several improved
approaches to Monte Carlo event generation, relative to the post--LEP state of
the art. In this brief review, the emphasis is placed on approaches for 1)
consistently merging fixed--order matrix element calculations with parton
showers, 2) improving the parton shower algorithms themselves, and 3) improving
the description of the underlying event in hadron collisions.


title:
One-loop fermionic corrections to the instanton transition in two
  dimensional chiral Higgs model

abstract:
  The one-loop fermionic contribution to the probability of an instanton
transition with fermion number violation is calculated in the chiral Abelian
Higgs model in 1+1 dimensions, where the fermions have a Yukawa coupling to the
scalar field. The dependence of the determinant on fermionic, scalar and vector
mass is determined. We show in detail how to renormalize the fermionic
determinant in partial wave analysis, which is convenient for computations.


title: Gauged supersymmetric $\gs$--models and soft breaking terms

abstract:
  Supersymmetric non--linear $\gs$--models in four dimensions with a $D$--term
potentials can sometimes have singular kinetic metric terms. As the kinetic
terms of scalar fields and their chiral fermionic partners are determine by
this metric, it follow that their kinetic energy vanishes in the vacuum. In
previous work, it has been shown in a simple model that soft supersymmetry
breaking terms can lift the degenerate the sigma-model metric and provide a
consistent mass-spectra. In this letter I introduce soft breaking terms in a
more realistic models based on SO(10) and $E_6$ and compute the resulting mass
spectrum.


title: Two-Higgs-doublet model from the group-theoretic perspective

abstract:
  In the two-Higgs-doublet model, different Higgs doublets can be viewed as
components of a generic "hyperspinor". We decompose the Higgs potential of this
model into irreducible representations of the SU(2) group of transformations of
this hyperspinor. We discuss invariant combinations of the Higgs potential
parameters lambda_i that arise in this decomposition and provide simple and
concise sets of conditions for the hidden Z_2-symmetry, Peccei-Quinn symmetry,
and explicit CP-conservation in 2HDM. We show that some results obtained
previously by brute-force calculations are reduced to simple linear algebraic
statements in our approach.


title: Flavour Changing Neutral Currents and Inverted Sfermion Mass Hierarchy

abstract:
  We study the contraints on non-flavour-blind soft supersymmetry breaking
terms coming from flavour and CP violating processes in the presence of
hierarchical Yukawa couplings, and quantify how much these constraints are
weakened in the regions of the MSSM parameter space characterized by heavy
gauginos and multi-TeV sfermion masses, respectively. We also study the
inverted sfermion mass hierarchy scenario in the context of D-term
supersymmetry breaking, and show that generic hierarchical Yukawa couplings
with arbitrary phases require first generation squarks in the few 10 TeV range.


title:
Thoughts on Non-Perturbative Thermalization and Jet Quenching in Heavy
  Ion Collisions

abstract:
  We start by presenting physical arguments for the impossibility of
perturbative thermalization leading to (non-viscous) Bjorken hydrodynamic
description of heavy ion collisions. These arguments are complimentary to our
more formal argument presented in [hep-ph/0503038]. We argue that the success
of hydrodynamic models in describing the quark-gluon system produced in heavy
ion collisions could only be due to non-perturbative strong coupling effects.
We continue by studying non-perturbative effects in heavy ion collisions at
high energies. We model non-perturbative phenomena by an instanton ensemble. We
show that non-perturbative instanton vacuum fields may significantly contribute
to jet quenching in nuclear collisions. At the same time, the instanton
ensemble contribution to thermalization is likely to be rather weak, leading to
non-perturbative thermalization time comparable to the time of hadronization.
This example illustrates that jet quenching is not necessarily a signal of a
thermalized medium. Indeed, since the instanton models do not capture all the
effects of QCD vacuum (e.g. they do not account for confinement), there may be
other non-perturbative effects facilitating thermalization of the system.


title:
Effects of an extra $Z'$ gauge boson on the top quark decay $t --> c
  \gamma$

abstract:
  The effects of an extra $Z'$ gauge boson with family nonuniversal fermion
couplings on the rare top quark decay $t --> c $gamma$ are first examined in a
model independent way and then in the minimal 331 model. It is found that the
respective branching fraction is at most of the order of $10^{-8}$ for
$m_{Z'}=500$ GeV and dramatically decreases for a heavier $Z'$ boson. This
results is in sharp contrast with a previous evaluation of this decay in the
context of topcolor assisted technicolor models, which found that $B(t --> c
\gamma)\sim 10^{-6}$ for $m_{Z'}=1$ TeV.


title: Pion Electromagnetic Form Factor in the $K_T$ Factorization Formulae

abstract:
  Based on the light-cone (LC) framework and the $k_T$ factorization formalism,
the transverse momentum effects and the different helicity components'
contributions to the pion form factor $F_{\pi}(Q^2)$ are recalculated. In
particular, the contribution to the pion form factor from the higher helicity
components ($\lambda_1+\lambda_2=\pm 1$), which come from the spin-space Wigner
rotation, are analyzed in the soft and hard energy regions respectively. Our
results show that the right power behavior of the hard contribution from the
higher helicity components can only be obtained by fully keeping the $k_T$
dependence in the hard amplitude, and that the $k_T$ dependence in LC
wavefunction affects the hard and soft contributions substantially. A model for
the twist-3 wavefunction $\psi_p(x,\mathbf{k_\perp})$ of the pion has been
constructed based on the moment calculation by applying the QCD sum rules,
whose distribution amplitude has a better end-point behavior than that of the
asymptotic one. With this model wavefunction, the twist-3 contributions
including both the usual helicity components ($\lambda_1+\lambda_2=0$) and the
higher helicity components ($\lambda_1+\lambda_2=\pm 1$) to the pion form
factor have been studied within the modified pQCD approach. Our results show
that the twist-3 contribution drops fast and it becomes less than the twist-2
contribution at $Q^2\sim 10GeV^2$. The higher helicity components in the
twist-3 wavefunction will give an extra suppression to the pion form factor.
When all the power contributions, which include higher order in $\alpha_s$,
higher helicities, higher twists in DA and etc., have been taken into account,
it is expected that the hard contributions will fit the present experimental
data well at the energy region where pQCD is applicable.


title: Split Supersymmetry at Colliders

abstract:
  We consider the collider phenomenology of split-supersymmetry models. Despite
the challenging nature of the signals in these models the long-lived gluino can
be discovered with masses above 2 TeV at the LHC. At a future linear collider
we will be able to observe the renormalization group effects from split
supersymmetry on the chargino/neutralino mixing parameters, using measurements
of the neutralino and chargino masses and cross sections. This indirect
determination of chargino/neutralino anomalous Yukawa couplings is an important
check for supersymmetric models in general.


title: Black Hole Remnants at the LHC

abstract:
  Within the scenario of large extra dimensions, the Planck scale is lowered to
values soon accessible. Among the predicted effects, the production of TeV mass
black holes at the {\sc LHC} is one of the most exciting possibilities. Though
the final phases of the black hole's evaporation are still unknown, the
formation of a black hole remnant is a theoretically well motivated
expectation. We analyze the observables emerging from a black hole evaporation
with a remnant instead of a final decay. We show that the formation of a black
hole remnant yields a signature which differs substantially from a final decay.
We find the total transverse momentum of the black hole event to be
significantly dominated by the presence of a remnant mass providing a strong
experimental signature for black hole remnant formation.


title:
On the two-loop O(\alpha_s^2) corrections to the pole mass of the
  t-quark in the MSSM

abstract:
  The paper is devoted to the calculation of additional two-loop O(\alpha_s^2)
MSSM corrections to the relation between the pole mass of the t-quark and its
running mass in the DR scheme. The value of the second order contribution from
large mass expansion is studied. As a by-product we calcutated two-loop
anomalous dimension of the running quark DR-mass in the supersymmetric QCD.


title: Trapping Black Hole Remnants

abstract:
  Large extra dimensions lower the Planck scale to values soon accessible. The
production of TeV mass black holes at the {\sc LHC} is one of the most exciting
predictions. However, the final phases of the black hole's evaporation are
still unknown and there are strong indications that a black hole remnant can be
left. Since a certain fraction of such objects would be electrically charged,
we argue that they can be trapped. In this paper, we examine the occurrence of
such charged black hole remnants.
  These trapped remnants are of high interest, as they could be used to closely
investigate the evaporation characteristics. Due to the absence of background
from the collision region and the controlled initial state, the signal would be
very clear. This would allow to extract information about the late stages of
the evaporation process with high precision.


title: Volkov solution for two laser beams and ITER

abstract:
  We find the solution of the Dirac equation for two plane waves (laser beams)
and we determine the modified Compton formula for the scattering of two photons
on an alectron. The practical meaning of the two laser beams is, that two laser
beams impinging on a targed which is constituted from material in the form of a
foam, can replace 100-200 laser beams impinging on a normal targed. It means
that the nuclear fusion with two laser beams is realistic in combination with
the nuclear reactor such as ITER.


title: Model of Mass Varying Neutrinos in SUSY

abstract:
  We discuss the mass varying neutrino scenario in the supersymmetric theory.
In the case of the model with the single superfield, one needs the soft SUSY
breaking terms or the $\mu$ term. However, fine-tunings of some parameters are
required to be consistent with the cosmological data. In order to avoid the
fine-tuning, we discuss the model with two superfields, which is consistent
with the cosmological data. However, it is found that the left-handed neutrino
mixes with the neutrino of the dark sector maximally. Adding a right- handed
neutrino, which does not couple to the dark sector, we obtain a favorable model
in the phenomenology of the neutrino experiments. In this model, the
deceleration of the cosmological expansion converts to the acceleration near
$z\simeq 0.5$. The speed of sound $c_s$ becomes imaginary if we put
$\omega_0=-0.9$, which corresponds to $m_\nu^0=3.17\eV$. On the other hand, if
we take $\omega_0=-0.998$, which leads to $m_\nu^0=0.05\eV$, $c_s^2$ becomes
positive since $\omega$ evolves rapidly near the present epoch in our model.


title: Deviations from Tribimaximal Neutrino Mixing

abstract:
  Current neutrino data are consistent with the so-called tribimaximal mixing
scenario, which predicts \sin^2 \theta_{12}=1/3, zero U_{e3} and maximal
\theta_{23}. This implies a special form of the neutrino mass matrix.
Introducing small breaking terms in this mass matrix generates deviations from
the tribimaximal scheme and leads to testable correlations between the
parameters. They depend on where the perturbation is located in the mass
matrix. A special case of such perturbations are radiative corrections.
Alternative deviations from tribimaximal mixing may stem from contributions of
the charged lepton sector. If there is quark-lepton-unification and it is the
CKM matrix which corrects the tribimaximal mixing scheme, then almost maximal
CP violation and sizable deviation from zero U_{e3} are implied.


title: Anomaly-driven decay of massive vector bosons

abstract:
  We inquire if the total decay rate of neutral vector mesons can contain
relevant off-shell contributions from the triangle anomaly.
  The answer seems to be affirmative for the case of J/Psi, and as a byproduct
we get estimates of the decay width for neutral pions.


title: Neutrinos in Warped Extra Dimensions

abstract:
  Amongst the diverse propositions for extra dimensional scenarios, the model
of Randall and Sundrum (RS), which offers a solution for the long standing
puzzle of the gauge hierarchy problem, has attracted considerable attention
from both the theoretical and experimental points of view. In the context of
the RS model with gauge bosons and fermions living in the bulk, a novel type of
mechanism has arisen for interpreting the strong mass hierarchy of the Standard
Model fermions. This purely geometrical mechanism is based on a type and flavor
dependent localization of fermions along a warped extra dimension. Here, we
find concrete realizations of this mechanism, reproducing all the present
experimental data on masses and mixings of the entire leptonic sector. We
consider the case of Dirac neutrino masses (due to an additional right handed
neutrino) where the various constraints on RS parameter space are taken into
account. The scenarios, elaborated in this paper, generate the entire lepton
mass hierarchy and mixing, essentially, via the higher-dimensional mechanism,
as the Yukawa coupling dependence is chosen to be minimal. In addition, from
the above mechanism, we predict the typical lepton mixing angle 10^-5 <
sin(theta_13) < 10^-1, a neutrino mass spectrum with normal hierarchy and the
smallest neutrino mass to lie approximately in the range: 10^-11 eV < m_nu_1 <
10^-2 eV. A large part of the sin(theta_13) interval should be testable in
future neutrino experiments.


title:
ZFITTER: a semi-analytical program for fermion pair production in e+e-
  annihilation, from version 6.21 to version 6.42

abstract:
  ZFITTER is a Fortran program for the calculation of fermion pair production
and radiative corrections at high energy e+e- colliders; it is also suitable
for other applications where electroweak radiative corrections appear. ZFITTER
is based on a semi-analytical approach to the calculation of radiative
corrections in the Standard Model. We present a summary of new features of the
ZFITTER program version 6.42 compared to version 6.21. The most important
additions are: (i) some higher-order QED corrections to fermion pair
production, (ii) electroweak one-loop corrections to atomic parity violation,
(iii) electroweak one-loop corrections to nu-e nu-e-bar production, (iv)
electroweak two-loop corrections to the W boson mass and the effective weak
mixing angle.


title: Pion-delta sigma-term

abstract:
  We use a configuration space chiral model in order to evaluate nucleon and
delta sigma-terms. Analytic expressions are consistent with chiral counting
rules and give rise to expected non-analytic terms in the chiral limit. We
obtain the results $\sigma_N=46$ MeV and $\sigma_{\Delta}=32$ MeV, which are
very close to values extracted from experiment and produced by other groups.


title: Predicting Neutrinoless Double Beta Decay

abstract:
  We give predictions for the neutrinoless double beta decay rate in a simple
variant of the A_4 family symmetry model. We show that there is a lower bound
for the neutrinoless double beta decay amplitude even in the case of normal
hierarchical neutrino masses, corresponding to an effective mass parameter
|m_{ee}| >= 0.17 \sqrt{\Delta m^2_{ATM}}. This result holds both for the CP
conserving and CP violating cases. In the latter case we show explicitly that
the lower bound on |m_{ee}| is sensitive to the value of the Majorana phase. We
conclude therefore that in our scheme, neutrinoless double beta decay may be
accessible to the next generation of high sensitivity experiments.


title: Color Non-Singlet Spectroscopy

abstract:
  Study of the spectrum and structure of color non-singlet combinations of
quarks and antiquarks, neutralized by a non-dynamical compensating color
source, may provide an interesting way to address questions about QCD that
cannot be addressed by experiment at the present time. These states can be
simulated in lattice QCD and the results can be used to improve
phenomenological models of hadrons. Here these ideas are applied to color
triplet states of qqqq and qq bar q.


title: SuperWIMP Solutions to Small Scale Structure Problems

abstract:
  Collisionless, cold dark matter in the form of weakly-interacting massive
particles (WIMPs) is well-motivated in particle physics, naturally yields the
observed relic density, and successfully explains structure formation on large
scales. On small scales, however, it predicts too much power, leading to cuspy
halos, dense cores, and large numbers of subhalos, in apparent conflict with
observations. We consider superWIMP dark matter, produced with large velocity
in late decays at times 10^5 s - 10^8 s. As analyzed by Kaplinghat in a more
general setting, we find that superWIMPs have sufficiently large free-streaming
lengths and low phase space densities to help resolve small scale structure
problems while preserving all of the above-mentioned WIMP virtues.


title: Color Ferromagnetic Quark Matter in Neutron Stars

abstract:
  We show that color ferromagnetic phase of quark matter is energetically more
favored than color superconducting phases in neutron stars. Namely, increasing
baryon density in neutron stars transforms nuclear matter into the quark matter
of the color ferromagnetic phase. Further increase of the density makes the
quark matter take the color superconducting phases. We find that a critical
mass of the neutron star with such an internal structure is about
$1.6M_{\odot}$. We stress that analysis of gluon dynamics is crucial for
exploring dense quark matter.


title: HPL, a Mathematica implementation of the harmonic polylogarithms

abstract:
  In this paper, we present an implementation of the harmonic polylogarithm of
Remiddi and Vermaseren for Mathematica. It contains an implementation of the
product algebra, the derivative properties, series expansion and numerical
evaluation. The analytic continuation has been treated carefully, allowing the
user to keep the control over the definition of the sign of the imaginary
parts. Many options enables the user to adapt the behavior of the package to
his specific problem.


title: Saturation, traveling waves and fluctuations

abstract:
  In this talk I discuss the high energy asymptotics of QCD scattering, and its
similarity to a reaction-diffusion process. I also discuss detailed numerical
studies of the mean field approximation to this picture, i.e., the
Balitsky-Kovchegov equation.


title:
Astroparticle and Collider Physics as complementary sources for the
  study of string motivated supergravity models

abstract:
  We provide a study of the phenomenology of heterotic orbifold
compactifications scenarii within the context of supergravity effective
theories. Our investigation focuses on those models where the soft Lagrangian
is dominated by loop contributions to the various soft supersymmetry breaking
parameters, giving a mixed anomaly-gravity mediation model. We consider the
pattern of masses that are governed by these soft terms and investigate the
implications of certain indirect constraints on supersymmetric models. In this
framework, we point out how the complementarity between direct and indirect
detection of a neutralino Dark Matter, and futur accelerator prospects can
reduce considerably the parameter space of such models


title: Electric Charge Quantization in SU(3)_C X SU(3)_L X U(1)_X Models

abstract:
  Basing on the general photon eigenstate and the anomaly cancelation, we have
naturally explained the electric charge quantization in two models based on the
SU(3)_C X SU(3)_L X U(1)_X gauge group, namely in the minimal model and in the
model with right-handed neutrinos. In addition, we have shown that the electric
charges of the proton and of the electron are opposite; and the same happens
with the neutron and the neutrino. We argue that the electric charge
quantization is not dependent on the classical constraints on generating mass
to the fermions, but it is related closely with the generation number problem.
In fact, both problems are properly solved as the direct consequences of the
fermion content under the anomaly free conditions.


title:
The B -> pi pi, pi K Puzzles: Implications for Hadron Physics, New
  Physics and Rare Decays

abstract:
  The B-meson system is an interesting probe for the exploration of strong
interactions, the quark-flavour sector of the Standard Model, and the search
for new physics. In this programme, non-leptonic B decays, which are
particularly challenging from the point of view of QCD, play a key role. After
discussing strategies to deal with the corresponding hadronic matrix elements
of four-quark operators and popular avenues for new physics to manifest itself
in B decays, we focus on puzzling patterns in the B-factory data for B -> pi
pi, pi K decays; we explore their implications for hadron physics, new physics
and rare K and B decays.


title:
Understanding the role of Cahn and Sivers effects in Deep Inelastic
  Scattering

abstract:
  The role of intrinsic $k_\perp$ in semi-inclusive Deep Inelastic Scattering
(SIDIS) processes ($l p \to l h X$) is studied with exact kinematics within QCD
parton model at leading order; the dependence of the unpolarized cross section
on the azimuthal angle between the leptonic and the hadron production planes
(Cahn effect) is compared with data and used to estimate the average values of
$k_\perp$ both in quark distribution and fragmentation functions. The resulting
picture is applied to the description of the weighted single spin asymmetry
$A_{UT}^{\sin(\phi_\pi - \phi_S)}$ recently measured by the HERMES
collaboration at DESY; this allows to extract parameters for the quark Sivers
functions. The extracted Sivers functions give predictions for the COMPASS
measurement of $A_{UT}^{\sin(\phi_\pi - \phi_S)}$ in agreement with recent
data, while their contribution to HERMES $A_{UL}^{\sin\phi_\pi}$ is computed
and found to be small. Predictions for $A_{UT}^{\sin(\phi_K - \phi_S)}$ for
kaon production at HERMES are also given.


title:
The effective electroweak mixing angle $\sin^2\theta_{eff}$ with
  two-loop fermionic contributions

abstract:
  We present the results from a calculation of the full electroweak two-loop
fermionic contributions to the effective leptonic mixing angle of the $Z$
boson, $\sin^2\theta_{eff}$, in the Standard Model. On-shell renormalization
and analytic calculations are performed for the three-point vertex functions at
zero external momenta, whereas irreducible three-point integrals for
non-vanishing external momenta are evaluated semi-analytically applying two
different methods. Comparisons with a previous calculation show complete
agreement.


title:
Indirect Determination of the Higgs Mass Through Electroweak Radiative
  Corrections

abstract:
  Electroweak precision observables allow stringent tests of the Standard Model
at the quantum level and imply interesting bounds on the mass of the Higgs
boson through higher-order loop effects. Very significant constraints come
especially from the determination of the mass of the W boson and from the
effective leptonic weak mixing angle. After shortly reviewing the status of
theoretical computations of the W mass, the new calculation of two-loop
corrections with closed fermion loops to the effective leptonic weak mixing
angle is discussed in detail. The phenomenological implications of the new
result are analyzed including an estimate of remaining uncertainties.


title: Instanton-Induced Processes - An Overview

abstract:
  A first part of this review is devoted to a summary of our extensive studies
of the discovery potential for instanton(I)-induced, deep-inelastic processes
at HERA. Included are some key issues about I-perturbation theory, an
exploitation of crucial lattice constraints and a status report about the
recent I-search results by the HERA collaborations H1 and ZEUS in relation to
our predictions. Next follows a brief outline of an ongoing project concerning
a broad exploration of the discovery potential for hard instanton processes at
the LHC. I then turn to an overview of our work on high-energy processes,
involving larger-sized instantons. I shall mainly focus on the phenomenon of
saturation at small Bjorken-x from an instanton perspective. In such a
framework, the saturation scale is associated with the conspicuous average
instanton size (~0.5 fm), as known from lattice simulations. Another central
and intriguing result is the identification of the "Colour Glass Condensate"
with the QCD sphaleron state.