title:
Magneto-optical and micromagnetic simulation study the current driven
  domain wall motion in ferromagnetic (Ga,Mn)As

abstract:
  We have studied current-driven domain wall motion in modified
Ga_0.95Mn_0.05As Hall bar structures with perpendicular anisotropy by using
spatially resolved Polar Magneto-Optical Kerr Effect Microscopy and
micromagnetic simulation. Regardless of the initial magnetic configuration, the
domain wall propagates in the opposite direction to the current with critical
current of 1~2x10^5A/cm^2. Considering the spin transfer torque term as well as
various effective magnetic field terms, the micromagnetic simulation results
are consistent with the experimental results. Our simulated and experimental
results suggest that the spin-torque rather than Oersted field is the reason
for current driven domain wall motion in this material.


title:
A proof of the uniform boundedness of solutions to the wave equation on
  slowly rotating Kerr backgrounds

abstract:
  We consider Kerr spacetimes with parameters a and M such that |a|<< M,
Kerr-Newman spacetimes with parameters |Q|<< M, |a|<< M, and more generally,
stationary axisymmetric black hole exterior spacetimes which are sufficiently
close to a Schwarzschild metric with parameter M>0, with appropriate geometric
assumptions on the plane spanned by the Killing fields. We show uniform
boundedness on the exterior for sufficiently regular solutions to the scalar
homogeneous wave equation. In particular, the bound holds up to and including
the event horizon. No unphysical restrictions are imposed on the behaviour of
the solution near the bifurcation surface of the event horizon. The pointwise
estimate derives in fact from the uniform boundedness of a positive definite
energy flux. Note that in view of the very general assumptions, the
separability properties of the wave equation on the Kerr background are not
used.


title: Integrable peakon equations with cubic nonlinearity

abstract:
  We present a new integrable partial differential equation found by Vladimir
Novikov. Like the Camassa-Holm and Degasperis-Procesi equations, this new
equation admits peaked soliton (peakon) solutions, but it has nonlinear terms
that are cubic, rather than quadratic. We give a matrix Lax pair for V.
Novikov's equation, and show how it is related by a reciprocal transformation
to a negative flow in the Sawada-Kotera hierarchy. Infinitely many conserved
quantities are found, as well as a bi-Hamiltonian structure. The latter is used
to obtain the Hamiltonian form of the finite-dimensional system for the
interaction of $N$ peakons, and the two-body dynamics (N=2) is explicitly
integrated. Finally, all of this is compared with some analogous results for
another cubic peakon equation derived by Zhijun Qiao.


title: Translocation Dynamics with Attractive Nanopore-Polymer Interactions

abstract:
  Using Langevin dynamics simulations, we investigate the influence of
polymer-pore interactions on the dynamics of biopolymer translocation through
nanopores. We find that an attractive interaction can significantly change the
translocation dynamics. This can be understood by examining the three
components of the total translocation time $\tau \approx \tau_1+\tau_2+\tau_3$
corresponding to the initial filling of the pore, transfer of polymer from the
\textit{cis} side to the \textit{trans} side, and emptying of the pore,
respectively. We find that the dynamics for the last process of emptying of the
pore changes from non-activated to activated in nature as the strength of the
attractive interaction increases, and $\tau_3$ becomes the dominant
contribution to the total translocation time for strong attraction. This leads
to a new dependence of $\tau$ as a function of driving force and chain length.
Our results are in good agreement with recent experimental findings, and
provide a possible explanation for the different scaling behavior observed in
solid state nanopores {\it vs.} that for the natural $\alpha$-hemolysin
channel.


title: Dynamical Scaling Exponents for Polymer Translocation through a Nanopore

abstract:
  We determine the scaling exponents of polymer translocation (PT) through a
nanopore by extensive computer simulations of various microscopic models for
chain lengths extending up to N=800 in some cases. We focus on the scaling of
the average PT time $\tau \sim N^{\alpha}$ and the mean-square change of the PT
coordinate $<s^2(t)> \sim t^\beta$. We find $\alpha=1+2\nu$ and
$\beta=2/\alpha$ for unbiased PT in 2D and 3D. The relation $\alpha \beta=2$
holds for driven PT in 2D, with crossover from $\alpha \approx 2\nu$ for short
chains to $\alpha \approx 1+\nu$ for long chains. This crossover is, however,
absent in 3D where $\alpha = 1.42 \pm 0.01$ and $\alpha \beta \approx 2.2$ for
$N \approx 40-800$.


title: Sensitivity to new physics: a_e vs. a_mu

abstract:
  At present it is generally believed that ``new physics'' effects contribute
to leptonic anomalous magnetic moment, a_l, via quantum loops only and they are
proportional to the squared lepton mass, (m_l)^2. An alternative mechanism for
a contribution by new physics is proposed. It occurs at the tree level and
exhibits a linear rather than quadratic dependence on m_l. This leads to a much
larger sensitivity of a_e to the new physics than was expected so far.


title: General relativistic treatment of LISA optical links

abstract:
  LISA is a joint space mission of the NASA and the ESA for detecting low
frequency gravitational waves in the band $10^{-5} - 1$ Hz. In order to attain
the requisite sensitivity for LISA, the laser frequency noise must be
suppressed below the other secondary noises such as the optical path noise,
acceleration noise etc. This is achieved by combining time-delayed data for
which precise knowledge of time-delays is required. The gravitational field,
mainly that of the Sun and the motion of LISA affect the time-delays and the
optical links. Further, the effect of the gravitational field of the Earth on
the orbits of spacecraft is included. This leads to additional flexing over and
above that of the Sun. We have written a numerical code which computes the
optical links, that is, the time-delays with great accuracy $\sim 10^{-2}$
metres - more than what is required for time delay interferometry (TDI) - for
most of the orbit and with sufficient accuracy within $\sim 10$ metres for an
integrated time window of about six days, when one of the arms tends to be
tangent to the orbit. Our analysis of the optical links is fully general
relativistic and the numerical code takes into account effects such as the
Sagnac, Shapiro delay, etc.. We show that with the deemed parameters in the
design of LISA, there are symmetries inherent in the configuration of LISA and
in the physics, which may be used effectively to suppress the residual laser
noise in the modified first generation TDI. We demonstrate our results for some
important TDI variables.


title:
Microbial genome as a fluctuating system: Distribution and correlation
  of coding sequence lengths

abstract:
  The length of coding sequence series in microbial genomes were regarded as a
fluctuating system and characterized by the methods of statistical physics. The
distribution and the correlatin properties of 50 genomes including bacteria and
several archaea were investigated. The distribution was investigated by
rank-size analysis (Zipf's law. We found that coding sequence lengths series do
not obey Zipf's law contrary to natural languages. The distribution was found
to be more closely to an exponential distribution. The correlation appeared to
be similar to natural languages. Segmentation analysis of the series showed to
be short range memory systems.


title: On two quantum approaches to adaptive mutations in bacteria

abstract:
  I compare two quantum-theoretical approaches to the phenomenon of adaptive
mutations, termed here Q-cell and Q-genome. I use 'fluctuation trapping' model
as a general framework. I introduce notions of R-error and D-error and argue
that the 'fluctuation trapping' model has to employ a correlation between the
R- and D- errors. Further, I compare how the two approaches can justify the
R-D-error correlation, focusing on the advantages of the Q-cell approach. The
positive role of environmentally induced decoherence (EID) on both steps of the
adaptation process is emphasized. A starving bacterial cell is proposed to be
in an einselected state. The intracellular dynamics in this state has a unitary
character and I propose to interpret it as 'exponential growth in imaginary
time', analogously to the commonly considered 'diffusion' interpretation of the
Schroedinger equation. Addition of a substrate leads to Wick rotation and a
switch from 'imaginary time' reproduction to a 'real time' reproduction regime.
Due to the variations at the genomic level (such as base tautomery), the
starving cell has to be represented as a superposition of different components,
all 'reproducing in imaginary time'. Adidtion of a selective substrate,
allowing only one of these components to amplify, will cause Wick rotation and
amplification of this component, thus justifying the occurence of the R-D-error
correlation. Further ramifications of the proposed ideas for evolutionary
theory are discussed.


title:
Manifestation of vortex depinning transition in nonlinear
  current-voltage characteristics of polycrystalline superconductor
  Y_{1-x}Pr_{x}Ba_2Cu_3O_7

abstract:
  We present our recent results on the temperature dependence of
current-voltage characteristics for polycrystalline Y_{1-x}Pr_{x}Ba_2Cu_3O_7
superconductors with x = 0.0, 0.1 and 0.3. The experimental results are found
to be reasonably well fitted for all samples by a power like law. According to
the theoretical interpretation of the obtained results, nonlinear deviation of
our current-voltage characteristics curves from Ohmic behavior below Tc is
attributed to the manifestation of dissipation processes related to the current
induced depinning of Abrikosov vortices.


title: Microscopic justification of the Equal Filling approximation

abstract:
  The Equal Filling Approximation, a procedure widely used in mean field
calculations to treat the dynamics of odd nuclei in a time reversal invariant
way, is justified as the consequence of a variational principle over an average
energy functional. The ideas of Statistical Quantum Mechanics are employed in
the justification. As an illustration of the method, the ground and lowest
lying states of some octupole deformed Radium isotopes are computed.


title: Remarks on lines and minimal rational curves

abstract:
  We determine all of lines in the moduli space $M$ of stable bundles for
arbitrary rank and degree. A further application of minimal rational curves is
also given in last section.


title:
A universal inequality between angular momentum and horizon area for
  axisymmetric and stationary black holes with surrounding matter

abstract:
  We prove that for sub-extremal axisymmetric and stationary black holes with
arbitrary surrounding matter the inequality $8\pi|J|<A$ holds, where $J$ is the
angular momentum and $A$ the horizon area of the black hole.


title:
Comprehensive Analysis of Dewetting Profiles to Quantify Hydrodynamic
  Slip

abstract:
  Hydrodynamic slip of Newtonian liquids is a new phenomenon, the origin of
which is not yet clarified. There are various direct and indirect techniques to
measure slippage. Here we describe a method to characterize the influence of
slippage on the shape of rims surrounding growing holes in thin polymer films.
Atomic force microscopy is used to study the shape of the rim; by analyzing its
profile and applying an appropriate lubrication model we are able to determine
the slip length for polystyrene films. In the experiments we study polymer
films below the entanglement length that dewet from hydrophobized (silanized)
surfaces. We show that the slip length at the solid/liquid interface increases
with increasing viscosity. The correlation between viscosity and slip length is
dependent on the type of silanization. This indicates a link between the
molecular mechanism of the interaction of polymer chains and silane molecules
under flow conditions that we will discuss in detail.


title: A Novel Attack Strategy on Entanglement Swapping QKD Protocols

abstract:
  Li et al. presented a protocol [Int. Journal of Quantum Information, Vol. 4,
No. 6 (2006) 899-906] for quantum key distribution based on entanglement
swapping. In this protocol they use random and certain bits to construct a
classical key and they claim that this key is secure. In our article we show
that the protocol by Li et al. is insecure presenting a new type of attack
strategy which gives an adversary full information about the key without being
detected. This strategy is based on entanglement swapping, too, and manages to
preserve the correlation between the measurement results of the legitimate
parties. Further we present a modified version of the protocol and show that it
is secure against this new attack strategy.


title: Network Connection Games with Disconnected Equilibria

abstract:
  In this paper we extend a popular non-cooperative network creation game (NCG)
to allow for disconnected equilibrium networks. There are n players, each is a
vertex in a graph, and a strategy is a subset of players to build edges to. For
each edge a player must pay a cost \alpha, and the individual cost for a player
represents a trade-off between edge costs and shortest path lengths to all
other players. We extend the model to a penalized game (PCG), for which we
reduce the penalty counted towards the individual cost for a pair of
disconnected players to a finite value \beta. Our analysis concentrates on
existence, structure, and cost of disconnected Nash and strong equilibria.
Although the PCG is not a potential game, pure Nash equilibria always and pure
strong equilibria very often exist. We provide tight conditions under which
disconnected Nash (strong) equilibria can evolve. Components of these
equilibria must be Nash (strong) equilibria of a smaller NCG. However, in
contrast to the NCG, for almost all parameter values no tree is a stable
component. Finally, we present a detailed characterization of the price of
anarchy that reveals cases in which the price of anarchy is \Theta(n) and thus
several orders of magnitude larger than in the NCG. Perhaps surprisingly, the
strong price of anarchy increases to at most 4. This indicates that global
communication and coordination can be extremely valuable to overcome socially
inferior topologies in distributed selfish network design.


title:
Stratification of sunspot umbral dots from inversion of Stokes profiles
  recorded by Hinode

abstract:
  This work aims to constrain the physical nature of umbral dots (UDs) using
high-resolution spectropolarimetry. Full Stokes spectra recorded by the
spectropolarimeter on Hinode of 51 UDs in a sunspot close to the disk center
are analyzed. The height dependence of the temperature, magnetic field vector,
and line-of-sight velocity across each UD is obtained from an inversion of the
Stokes vectors of the two FeI lines at 630 nm. No difference is found at higher
altitudes (-3 <= log(tau) <= -2) between the UDs and the diffuse umbral
background. Below that level the difference rapidly increases, so that at the
continuum formation level (log(tau) = 0) we find on average a temperature
enhancement of 570 K, a magnetic field weakening of 510 G, and upflows of 800
m/s for peripheral UDs, whereas central UDs display an excess temperature of on
average 550 K, a field weakening of 480 G, and no significant upflows. The
results for, in particular, the peripheral UDs, including cuts of magnetic
vector and velocity through them, look remarkably similar to the output of
recent radiation MHD simulations. They strongly suggest that UDs are produced
by convective upwellings.


title:
Effect of strong electric fields on ferroelectric and metal-insulator
  transitions

abstract:
  It is shown that a sufficiently strong external electric field causes a
decrease in the transition temperature of ferroelectric, antiferroelectric, and
metal-insulator transitions. The temperature dependence of the critical
electric field suppressing a low-temperature phase is obtained. The relation
between the low-temperature charge gap (the band gap) in the insulating phase
and the metal-insulator transition temperature is also inferred.


title:
Edge disorder induced Anderson localization and conduction gap in
  graphene nanoribbons

abstract:
  We study the effect of the edge disorder on the conductance of the graphene
nanoribbons (GNRs). We find that only very modest edge disorder is sufficient
to induce the conduction energy gap in the otherwise metallic GNRs and to lift
any difference in the conductance between nanoribbons of different edge
geometry. We relate the formation of the conduction gap to the pronounced edge
disorder induced Anderson-type localization which leads to the strongly
enhanced density of states at the edges, formation of surface-like states and
to blocking of conductive paths through the ribbons.


title:
Electromagnetically induced transparency of an interacting cold Rydberg
  ensemble

abstract:
  We study electromagnetically induced transparency (EIT) of a weakly
interacting cold Rydberg gas. We show that the onset of interactions is
manifest as a depopulation of the Rydberg state and numerically model this
effect by adding a density-dependent non-linear term to the optical Bloch
equations. In the limit of a weak probe where the depopulation effect is
negligible, we observe no evidence of interaction induced decoherence and
obtain a narrow Rydberg dark resonance with a linewidth of <600 kHz, limited by
the Rabi frequency of the coupling beam


title: Constraint Dynamics and Gravitons in Three Dimensions

abstract:
  The complete non-linear three-dimensional Einstein gravity with gravitational
Chern-Simons term and cosmological constant are studied in dreibein
formulation. The constraints and their algebras are computed in an explicit
form. From counting the number of first and second class constraints, the
number of dynamical degrees of freedom, which equals to the number of
propagating graviton modes, is found to be 1, "regardless of" the value of
cosmological constant. I note also that the usual equivalence with Chern-Simons
gauge theory does "not" work for general circumstances.


title: Extra charmonium states as bag-quarkonia

abstract:
  Exotic states in the charmonium family are systematically treated in the
framework of simplest model with an effective coulomb-like interaction of heavy
quark and antiquark in the presence of static excitation of quark-gluon modes
responsible for a nonperturbative term of potential, which provides with the
confinement of quarks, in terms of bag over the threshold in the excitation
spectrum of vacuum fields. Once the spectrum has got quite a wide mass gap, it
allows us to approximate the bag contribution into the potential by a constant
value of bag mass at low distances less than the bag size. The bag mass can be
evaluated in a constituent model. The analysis is given for the bag
contribution into the distribution over the invariant mass of two pions in the
hadronic transition between the S-wave states of bag-quarkonium and heavy
quarkonium, that leads to the anomaly violating the chiral limit in the region
of low invariant masses, which agrees with the observational data. Leptonic
constants of vector states are investigated in the presence of exotic states in
the framework of quasilocal sum rules. The extra states allow us to improve the
consistency of describing the measured widths of leptonic decays for the
complete set of vector states in the charmonium family.


title: Chemical Bonding in the Boron Buckyball

abstract:
  A symmetry analysis of the valence shell in the boron buckyball B80, shows a
perfect match with the symmetry of the valence shell in C60 .The cap atoms
participate in the bonding by 30 orbitals which transform as the sigma bonds
along the 6-6 edges. Far reaching consequences for chemical and physical
properties of B80, which until now only exists in silico, are expected.


title: Mass Loss From Evolved Stars in Elliptical Galaxies

abstract:
  Most of the X-ray emitting gas in early-type galaxies probably originates
from red giant mass loss and here we model the interaction between this stellar
mass loss and the hot ambient medium. Using two-dimensional hydrodynamic
simulations, we adopt a temperature for the ambient medium of 3E6 K along with
a range of ambient densities and stellar velocities. When the stellar velocity
is supersonic relative to the ambient medium, a bow shock occurs, along with a
shock driven into the stellar ejecta, which heats only a fraction of the gas.
Behind the bow shock, a cool wake develops but the fast flow of the hot medium
causes Kelvin-Helmholtz instabilities to grow and these fingers are shocked and
heated (without radiative cooling). Along with the mixing of this wake material
with the hot medium, most of the stellar ejecta is heated to approximately the
temperature of the hot ambient medium within 2 pc of the star. With the
addition of radiative cooling, some wake material remains cool (< 1E5 K),
accounting for up to 25% of the stellar mass loss. Less cooled gas survives
when the ambient density is lower or when the stellar velocity is higher than
in our reference case. These results suggest that some cooled gas should be
present in the inner part of early-type galaxies that have a hot ambient
medium. These calculations may explain the observed distributed optical
emission line gas as well as the presence of dust in early-type galaxies.


title: Exact Edgeworth expansion for a L\'{e}vy process

abstract:
  The one dimensional distribution of a L\'{e}vy process is not known in
general even though its characteristic function is given by the famous
L\'{e}vy-Khinchine theorem. This article gives an exact series representation
for the one dimensional distribution of a L\'{e}vy process satisfying certain
moment conditions. Moreover, this work clarifies an old result by Cram\'{e}r on
Edgeworth expansions for the distribution function of a L\'{e}vy process.


title: On the space of elliptic genera

abstract:
  Invariance under modular transformations and spectral flow restrict the
possible spectra of superconformal field theories (SCFT). This paper presents a
technique to calculate the number of constraints on the polar spectra of
N=(2,2) and N=(4,0) SCFT's by analyzing the elliptic genus. The polar spectrum
corresponds to the principal part of a Laurent expansion derived from the
elliptic genus. From the point of view of the AdS_3/CFT_2 correspondence, these
are the states which lie below the cosmic censorship bound in classical
gravity. The dimension of the space of elliptic genera is obtained as the
number of coefficients of the principal part minus the number of constraints.
As an additional illustration of the technique, the constraints on the spectrum
of N=4 topologically twisted Yang-Mills on CP^2 are discussed.


title: Search for Deconfined Criticality: SU(2) D\'{e}j\`{a} Vu

abstract:
  Monte Carlo simulations of the SU(2)-symmetric deconfined critical point
action reveal strong violations of scale invariance for the deconfinement
transition. We find compelling evidence that the generic runaway
renormalization flow of the gauge coupling is to a weak first order transition,
similar to the case of U(1)$\times$U(1) symmetry. Our results imply that recent
numeric studies of the N\`{e}el antiferromagnet to valence bond solid quantum
phase transition in SU(2)-symmetric models were not accurate enough in
determining the nature of the transition.


title:
Dielectric and polarization experiments in high loss dielectrics: a word
  of caution

abstract:
  The recent quest for improved functional materials like high permittivity
dielectrics and/or multiferroics has triggered an intense wave of research.
Many materials have been checked for their dielectric permittivity or their
polarization state. In this report, we call for caution when samples are
simultaneously displaying insulating behavior and defect-related conductivity.
Many oxides containing mixed valent cations or oxygen vacancies fall in this
category. In such cases, most of standard experiments may result in effective
high dielectric permittivity which cannot be related to ferroelectric
polarization. Here we list few examples of possible discrepancies between
measured parameters and their expected microscopic origin.


title: Stability and dewetting of thin liquid films

abstract:
  The stability of thin liquid coatings is of fundamental interest in every-
day life. Homogeneous and non-volatile liquid coatings may dewet either by
heterogeneous nucleation, thermal nucleation, or spinodal dewetting. Wetting
and dewetting is explained on a fundamental level, including a discussion of
relevant interactions. The article will also address the various dewetting
scenarios and explain how the effective interface potential governs the
behavior obtained for various stratified substrates and film thicknesses.


title: On ortho-positronium and gauge

abstract:
  Binding energy of the $1^-$ state (ortho-positronium) in QED is calculated
using the one-photon exchange Bethe-Salpeter equation in the Feynman and
Coulomb gauges for different coupling constants $\alpha$. Calculations show
there is a remarkable difference in values of the binding energy for different
coupling constants in these two gauges.


title: Quantization of Prior Probabilities for Hypothesis Testing

abstract:
  Bayesian hypothesis testing is investigated when the prior probabilities of
the hypotheses, taken as a random vector, are quantized. Nearest neighbor and
centroid conditions are derived using mean Bayes risk error as a distortion
measure for quantization. A high-resolution approximation to the
distortion-rate function is also obtained. Human decision making in segregated
populations is studied assuming Bayesian hypothesis testing with quantized
priors.


title:
On full-fledged supergravity cosmologies and their Weyl group
  asymptotics

abstract:
  We consider a class of cosmological solutions of d=4, N=2 supergravity
theories coupled to vector multiplets. The solutions result from performing a
compactification to three dimensions, where the theory reduces to a symmetric
space sigma model coupled to gravity and where the resulting equations of
motion are integrable. We describe in detail how the three-dimensional
solutions can be uplifted to four dimensions again. The four-dimensional
cosmologies are generically characterized by an algebra of translational
isometries that is of Heisenberg type. We give explicit examples of these
cosmologies for the S-T-U model and comment also on their uplift to 10
dimensions by interpreting them as solutions of a truncation of type IIB
supergravity on a K3 x T^2/Z_2 orientifold.


title: Nickel-based layered superconductor, LaNiOAs

abstract:
  Rietveld analysis of the powder X-ray diffraction of a new layered
oxyarsenide, LaNiOAs, which was synthesized by solid-state reactions, revealed
that LaNiOAs belongs to the tetragonal ZrCuSiAs-type structure (P4/nmm) and is
composed of alternating stacks of La-O and Ni-As layers. The electrical and
magnetic measurements demonstrated that LaNiOAs exhibits a superconducting
transition at 2.4 K, and above this, LaNiOAs shows metallic conduction and
Pauli paramagnetism. The diamagnetic susceptibility measured at 1.8 K
corresponded to ~20% of perfect diamagnetic susceptibility, substantiating that
LaNiOAs is a bulk superconductor.


title:
Atomic multiplet calculation of 3d_{5/2} -> 4f resonant x-ray
  diffraction from Ho metal

abstract:
  We compare for Ho metal the x-ray absorption spectrum and the resonant soft
x-ray diffraction spectra obtained at the $3d_{5/2} \to 4f$ ($M_5$) resonance
for the magnetic 1st and 2nd order diffraction peaks $(0,0,\tau)$ and
$(0,0,2\tau)$ with the result of an atomic multiplet calculation. We find a
good agreement between experiment and simulation giving evidence that this kind
of simulation is well suited to quantitatively analyze resonant soft x-ray
diffraction data from correlated electron systems.


title: Wavelet Analysis of AGN X-Ray Time Series: A QPO in 3C 273?

abstract:
  Quasi-periodic signals have yielded important constraints on the masses of
black holes in galactic X-ray binaries, and here we extend this to active
galactic nuclei (AGNs). We employ a wavelet technique to analyze 19
observations of 10 AGNs obtained with the XMM-Newton EPIC pn camera. We report
the detection of a candidate 3.3 ks quasi period in 3C 273. If this period
represents an orbital timescale originating near a last stable orbit of 3Rs, it
implies a central black hole mass of 7.3x10^6 Msun. For a maximally rotating
black hole with a last stable orbit of 0.6Rs, a central black hole mass of
8.1x10^7 Msun is implied. Both of these estimates are substantially lower than
previous reverberation-mapping results, which place the central black hole mass
of 3C 273 at about 2.35 x10^8 Msun. Assuming that this reverberation mass is
correct, the X-ray quasi period would be caused by a higher order oscillatory
mode of the accretion disk.


title: How much random a random network is : a random matrix analysis

abstract:
  We analyze complex networks under random matrix theory framework.
Particularly, we show that $\Delta_3$ statistic, which gives information about
the long range correlations among eigenvalues, provides a qualitative measure
of randomness in networks. As networks deviate from the regular structure,
$\Delta_3$ follows random matrix prediction of linear behavior, in
semi-logarithmic scale with the slope of $1/\pi^2$, for the longer scale.


title:
Universal L^p improving for averages along polynomial curves in low
  dimensions

abstract:
  We prove sharp $L^p-L^q$ estimates for averaging operators along general
polynomial curves in two and three dimensions. These operators are
translation-invariant, given by convolution with the so-called affine arclength
measure of the curve and we obtain universal bounds over the class of curves
given by polynomials of bounded degree. Our method relies on a geometric
inequality for general vector polynomials together with a combinatorial
argument due to M. Christ. Almost sharp Lorentz space estimates are obtained as
well.


title: Building an entanglement measure on physical ground

abstract:
  We introduce on physical grounds a new measure of multipartite entanglement
for pure states. The function we define is discriminant and monotone under LOCC
and moreover can be expressed in terms of observables of the system.


title:
On AdS/QCD correspondence and the partonic picture of deep inelastic
  scattering

abstract:
  We critically examine the question of scaling of the Deep Inelastic
  Scattering process in the medium Bjorken x region on a scalar boson in the
framework of the AdS/QCD correspondence. To get the right polarization
structure of the forward electroproduction amplitude, we show that one needs to
add (at least) the scalar to scalar and scalar to vector hadronic amplitudes.
This illustrates how the partonic picture may emerge from a simple scenario
based on the AdS/QCD correspondence, provided one allows the conformal
dimension of the hadronic field to equal 1 and use the concept of "hadron -
parton duality" .


title: Optimized quantum random-walk search algorithms

abstract:
  Shenvi, Kempe and Whaley's quantum random-walk search (SKW) algorithm [Phys.
Rev. A 67, 052307 (2003)] is known to require $O(\sqrt N)$ number of oracle
queries to find the marked element, where $N$ is the size of the search space.
The overall time complexity of the SKW algorithm differs from the best
achievable on a quantum computer only by a constant factor. We present
improvements to the SKW algorithm which yield significant increase in success
probability, and an improvement on query complexity such that the theoretical
limit of a search algorithm succeeding with probability close to one is
reached. We point out which improvement can be applied if there is more than
one marked element to find.


title: A note on the quantum-tail effect on fusion reaction rate

abstract:
  A study is made of the power-law tail effect in the quantum particle
distribution over momentum on the nuclear fusion reactions. Our results do not
support the idea of averaging the fusion reaction cross-section over the
momentum distribution postulated and used in many publications.


title: LOFAR Transients and the Radio Sky Monitor

abstract:
  The study of transient and variable low-frequency radio sources is a key goal
for LOFAR, with an extremely broad science case ranging from relativistic jets
sources to pulsars, exoplanets, radio bursts at cosmological distances, the
identification of gravitational wave sources and even SETI. In this paper we
will very briefly summarize the science of the LOFAR Transients key science
project, will outline the capabilities of LOFAR for transient studies, and
introduce the LOFAR Radio Sky Monitor, a proposed mode in which LOFAR regularly
scans 2 pi radians of sky.


title:
Electronic and optical properties of ferromagnetic GaMnAs in a
  multi-band tight-binding approach

abstract:
  We consider the electronic properties of ferromagnetic bulk GaMnAs at zero
temperature using two realistic tight-binding models, one due to Tang and
Flatte and one due to Masek. In particular, we study the density of states, the
Fermi energy, the inverse participation ratio, and the optical conductivity
with varying impurity concentration x=0.01-0.15. The results are very sensitive
to the assumptions made for the on-site and hopping matrix elements of the Mn
impurities. For low concentrations, x<0.02, Masek's model shows only small
deviations from the case of p-doped GaAs with increased number of holes while
within Tang and Flatte's model an impurity-band forms. For higher
concentrations x, Masek's model shows minor quantitative changes in the
properties we studied while the results of the Tang and Flatte model exhibit
qualitative changes including strong localization of eigenstates with energies
close to the band edge. These differences between the two approaches are in
particular visible in the optical conductivity, where Masek's model shows a
Drude peak at zero frequency while no such peak is observed in Tang and
Flatte's model. Interestingly, although the two models differ qualitatively the
calculated effective optical masses of both models are similar within the range
of 0.4-1.0 of the free electron mass.


title:
Effective Operator for $dd$ Transitions in Nonresonant Inelastic X-ray
  Scattering

abstract:
  Recent experiments by Larson et al. demonstrate the feasibility of measuring
local $dd$ excitations using nonresonant inelastic X-ray scattering (IXS). We
establish a general framework for the interpretation where the $dd$ transitions
created in the scattering process are expressed in effective one-particle
operators that follow a simple selection rule. The different operators can be
selectively probed by employing their different dependence on the direction and
magnitude of the transferred momentum. We use the operators to explain the
presence of nodal directions and the nonresonant IXS in specific directions and
planes. We demonstrate how nonresonant IXS can be used to extract valuable
ground state information for orbiton excitations in manganite.


title:
Charge order in La_{1.8-x}Eu_{0.2}Sr_xCuO_4 studied by resonant soft
  X-ray diffraction

abstract:
  Resonant soft X-ray scattering with photon energies near the O K and the Cu
L3 edges was used to study charge ordering in the system
La_{1.8-x}Eu_{0.2}Sr_xCuO_4 as a function of temperature for x = 0.125 and
0.15. From the superstructure diffraction intensities a charge ordering with a
doping dependent wave vector is derived which is in this system well below the
transition temperature of the low-temperature tetragonal phase but well above
the onset of spin ordering. This indicates that charge ordering is the primary
driving force for the formation of stripe-like phases in two-dimensional doped
cuprates. Analysis of the lineshape of the scattered intensity as a function of
photon energy yields evidence for a high hole concentration in the stripes.


title:
On subexponentiality of the L\'evy measure of the diffusion inverse
  local time; with applications to penalizations

abstract:
  For a recurrent linear diffusion on $\R_+$ we study the asymptotics of the
distribution of its local time at 0 as the time parameter tends to infinity.
Under the assumption that the L\'evy measure of the inverse local time is
subexponential this distribution behaves asymtotically as a multiple of the
L\'evy measure. Using spectral representations we find the exact value of the
multiple. For this we also need a result on the asymptotic behavior of the
convolution of a subexponential distribution and an arbitrary distribution on
$\R_+.$ The exact knowledge of the asymptotic behavior of the distribution of
the local time allows us to analyze the process derived via a penalization
procedure with the local time. This result generalizes the penalizations
obtained in Roynette, Vallois and Yor \cite{rvyV} for Bessel processes.


title: Configuration spaces of rings and wickets

abstract:
  The main result in this paper is that the space of all smooth links in
Euclidean 3-space isotopic to the trivial link of n components has the same
homotopy type as its finite-dimensional subspace consisting of configurations
of n unlinked Euclidean circles (the "rings" in the title). There is also an
analogous result for spaces of arcs in upper half-space, with circles replaced
by semicircles (the "wickets" in the title). A key part of the proofs is a
procedure for greatly reducing the complexity of tangled configurations of
rings and wickets. This leads to simple methods for computing presentations for
the fundamental groups of these spaces of rings and wickets as well as various
interesting subspaces. The wicket spaces are also shown to be K(G,1)'s.


title: On the inadequacy of the logistic map for cryptographic applications

abstract:
  This paper analyzes the use of the logistic map for cryptographic
applications. The most important characteristics of the logistic map are shown
in order to prove the inconvenience of considering this map in the design of
new chaotic cryptosystems.


title:
Examination of the concept of degree of rate control by first-principles
  kinetic Monte Carlo simulations

abstract:
  The conceptual idea of degree of rate control (DRC) approaches is to identify
the "rate limiting step" in a complex reaction network by evaluating how the
overall rate of product formation changes when a small change is made in one of
the kinetic parameters. We examine two definitions of this concept by applying
it to first-principles kinetic Monte Carlo simulations of the CO oxidation at
RuO2(110). Instead of studying experimental data we examine simulations,
because in them we know the surface structure, reaction mechanism, the rate
constants, the coverage of the surface and the turn-over frequency at steady
state. We can test whether the insights provided by the DRC are in agreement
with the results of the simulations thus avoiding the uncertainties inherent in
a comparison with experiment. We find that the information provided by using
the DRC is non-trivial: It could not have been obtained from the knowledge of
the reaction mechanism and of the magnitude of the rate constants alone. For
the simulations the DRC provides furthermore guidance as to which aspects of
the reaction mechanism should be treated accurately and which can be studied by
less accurate and more efficient methods. We therefore conclude that a
sensitivity analysis based on the DRC is a useful tool for understanding the
propagation of errors from the electronic structure calculations to the
statistical simulations in first-principles kinetic Monte Carlo simulations.


title:
Dynamic nuclear polarization with simultaneous excitation of electronic
  and nuclear transitions

abstract:
  Dynamic nuclear polarization transfers spin polarization from electrons to
nuclei. We have achieved this by a new method, simultaneously exciting
transitions of electronic and nuclear spins. The efficiency of this technique
improves with increasing magnetic field. Experimental results are shown for
N@C60 with continuous-wave microwaves, which can be expected to produce even
higher polarization than the corresponding pulsed techniques for electron spins
greater than 1/2. The degree of nuclear polarization in this case can be easily
monitored through the intensities of the well resolved hyperfine components in
the EPR spectrum. The nuclear spin-lattice relaxation time is orders of
magnitude longer than that of the electrons.


title: Potential Polynomials and Motzkin Paths

abstract:
  A {\em Motzkin path} of length $n$ is a lattice path from $(0,0)$ to $(n,0)$
in the plane integer lattice $\mathbb{Z}\times\mathbb{Z}$ consisting of
horizontal-steps $(1, 0)$, up-steps $(1,1)$, and down-steps $(1,-1)$, which
never passes below the x-axis. A {\em $u$-segment {\rm (resp.} $h$-segment
{\rm)}} of a Motzkin path is a maximum sequence of consecutive up-steps ({\rm
resp.} horizontal-steps). The present paper studies two kinds of statistics on
Motzkin paths: "number of $u$-segments" and "number of $h$-segments". The
Lagrange inversion formula is utilized to represent the weighted generating
function for the number of Motzkin paths according to the statistics as a sum
of the partial Bell polynomials or the potential polynomials. As an
application, a general framework for studying compositions are also provided.


title: Adaptive design and analysis of supercomputer experiments

abstract:
  Computer experiments are often performed to allow modeling of a response
surface of a physical experiment that can be too costly or difficult to run
except using a simulator. Running the experiment over a dense grid can be
prohibitively expensive, yet running over a sparse design chosen in advance can
result in obtaining insufficient information in parts of the space,
particularly when the surface calls for a nonstationary model. We propose an
approach that automatically explores the space while simultaneously fitting the
response surface, using predictive uncertainty to guide subsequent experimental
runs. The newly developed Bayesian treed Gaussian process is used as the
surrogate model, and a fully Bayesian approach allows explicit measures of
uncertainty. We develop an adaptive sequential design framework to cope with an
asynchronous, random, agent--based supercomputing environment, by using a
hybrid approach that melds optimal strategies from the statistics literature
with flexible strategies from the active learning literature. The merits of
this approach are borne out in several examples, including the motivating
computational fluid dynamics simulation of a rocket booster.


title:
Supernovae in Early-Type Galaxies: Directly Connecting Age and
  Metallicity with Type Ia Luminosity

abstract:
  We have obtained optical spectra of 29 early-type (E/S0) galaxies that hosted
type Ia supernovae (SNe Ia). We have measured absorption-line strengths and
compared them to a grid of models to extract the relations between the
supernova properties and the luminosity-weighted age/composition of the host
galaxies. The same analysis was applied to a large number of early-type field
galaxies selected from the SDSS spectroscopic survey. We find no difference in
the age and abundance distributions between the field galaxies and the SN Ia
host galaxies. We do find a strong correlation suggesting that SNe Ia in
galaxies whose populations have a characteristic age greater than 5 Gyr are ~ 1
mag fainter at V(max) than those found in galaxies with younger populations.
However, the data cannot discriminate between a smooth relation connecting age
and supernova luminosity or two populations of SN Ia progenitors. We find that
SN Ia distance residuals in the Hubble diagram are correlated with host-galaxy
metal abundance, consistent with the predictions of Timmes, Brown & Truran
(2003). The data show that high iron abundance galaxies host less-luminous
supernovae. We thus conclude that the time since progenitor formation primarily
determines the radioactive Ni production while progenitor metal abundance has a
weaker influence on peak luminosity, but one not fully corrected by light-curve
shape and color fitters. Assuming no selection effects in discovering SNe Ia in
local early-type galaxies, we find a higher specific SN Ia rate in E/S0
galaxies with ages below 3 Gyr than in older hosts. The higher rate and
brighter luminosities seen in the youngest E/S0 hosts may be a result of recent
star formation and represents a tail of the "prompt" SN Ia progenitors.


title:
An SZ/X-ray galaxy cluster model and the X-ray follow-up of the Planck
  clusters

abstract:
  Sunyaev-Zel'dovich (SZ) cluster surveys will become an important cosmological
tool over next few years, and it will be essential to relate these new surveys
to cluster surveys in other wavebands. We present an empirical model of cluster
SZ and X-ray observables constructed to address this question and to motivate,
dimension and guide X-ray follow-up of SZ surveys. As an example application of
the model, we discuss potential XMM-Newton follow-up of Planck clusters.


title: Vanishing beta function for Grosse-Wulkenhaar model in a magnetic field

abstract:
  We prove that the beta function of the Grosse-Wulkenhaar model including a
magnetic field vanishes at all order of perturbations. We compute the
renormalization group flow of the relevant dynamic parameters and find a
non-Gaussian infrared fixed point. Some consequences of these results are
discussed.


title: Lorentzian Lie 3-algebras and their Bagger-Lambert moduli space

abstract:
  We classify Lie 3-algebras possessing an invariant lorentzian inner product.
The indecomposable objects are in one-to-one correspondence with compact real
forms of metric semisimple Lie algebras. We analyse the moduli space of
classical vacua of the Bagger-Lambert theory corresponding to these Lie
3-algebras. We establish a one-to-one correspondence between one branch of the
moduli space and compact riemannian symmetric spaces. We analyse the asymptotic
behaviour of the moduli space and identify a large class of models with moduli
branches exhibiting the desired N^{3/2} behaviour.


title: Photonic Dipole Contours of Ferrofluid Hele-Shaw Cell

abstract:
  This investigation describes and demonstrates a novel technique for the
visualization of magnetic fields. Two ferrofluid Hele-Shaw cells have been
constructed to facilitate the imaging of magnetic field lines. We deduce that
magnetically induced photonic band gap arrays similar to electrostatic liquid
crystal operation are responsible for the photographed images and seek to
mathematically prove the images are of dipole nature.
  A simple way of explaining this work is to think of the old magnetic iron
filling experiments; but now each iron filling is a molecule floating in a
liquid. Each molecule has the freedom to act as an independent lens that can be
aligned by an external magnetic field. Because each lens directs light, the
external field can be analyzed by following the light paths captured in the
photographs.


title: Perfect state transfer on a spin-chain without state initialization

abstract:
  We demonstrate that perfect state transfer can be achieved using an
engineered spin chain and clean local end-chain operations, without requiring
the initialization of the state of the medium nor fine tuning of
control-pulses. This considerably relaxes the prerequisites for obtaining
reliable transfer of quantum information across interacting-spin systems.
Moreover, it allows us to shed light on the interplay among purity,
entanglement and operations on a class of many-body systems potentially useful
for quantum information processing tasks.


title: Analytic approximation of matrix functions in $L^p$

abstract:
  We consider the problem of approximation of matrix functions of class $L^p$
on the unit circle by matrix functions analytic in the unit disk in the norm of
$L^p$, $2\le p<\be$. For an $m\times n$ matrix function $\Phi$ in $L^p$, we
consider the Hankel operator $H_\Phi:H^q(C^n)\to H^2_-(C^m)$, $1/p+1/q=1/2$. It
turns out that the space of $m\times n$ matrix functions in $L^p$ splits into
two subclasses: the set of respectable matrix functions and the set of weird
matrix functions. If $\Phi$ is respectable, then its distance to the set of
analytic matrix functions is equal to the norm of $H_\Phi$. For weird matrix
functions, to obtain the distance formula, we consider Hankel operators defined
on spaces of matrix functions. We also describe the set of $p$-badly
approximable matrix functions in terms of special factorizations and give a
parametrization formula for all best analytic approximants in the norm of
$L^p$. Finally, we introduce the notion of $p$-superoptimal approximation and
prove the uniqueness of a $p$-superoptimal approximant for rational matrix
functions.


title:
Chaotic dynamics in the Volterra predator-prey model via linked twist
  maps

abstract:
  We prove the existence of infinitely many periodic solutions and complicated
dynamics, due to the presence of a topological horseshoe, for the classical
Volterra predator--prey model with a periodic harvesting. The proof relies on
some recent results about chaotic planar maps combined with the study of
geometric features which are typical of linked twist maps.


title:
Group Theoretical Analysis of the Wave Function of the $[{\bf 70},1^-]$
  Nonstrange Baryons in the $1/N_c$ Expansion

abstract:
  Using standard group theoretical techniques we construct the exact wave
function of the $[{\bf 70},1^-]$ multiplet in the orbital, spin and flavor
space. This symmetric wave function is compared to that customarily used in the
$1/N_c$ expansion, which is asymmetric. The comparison is made by analyzing the
matrix elements of various operators entering the mass formula. These matrix
elements are calculated by the help of isoscalar factors of the permutation
group, specially derived for this purpose as a function of $N_c$. We also
compare two distinct methods used in the study of the $[{\bf 70},1^-]$
multiplet. In the first method the generators are divided into two parts, one
part acting on a subsystem of $N_c-1$ quarks called core and another on the
separated quark. In the second method the system is treated as a whole. We show
that the latter is simpler and allows to clearly reveal the physically
important operators in the mass formula.


title: A semantic space for modeling children's semantic memory

abstract:
  The goal of this paper is to present a model of children's semantic memory,
which is based on a corpus reproducing the kinds of texts children are exposed
to. After presenting the literature in the development of the semantic memory,
a preliminary French corpus of 3.2 million words is described. Similarities in
the resulting semantic space are compared to human data on four tests:
association norms, vocabulary test, semantic judgments and memory tasks. A
second corpus is described, which is composed of subcorpora corresponding to
various ages. This stratified corpus is intended as a basis for developmental
studies. Finally, two applications of these models of semantic memory are
presented: the first one aims at tracing the development of semantic
similarities paragraph by paragraph; the second one describes an implementation
of a model of text comprehension derived from the Construction-integration
model (Kintsch, 1988, 1998) and based on such models of semantic memory.


title: Differentiability of functions of contractions

abstract:
  In this paper we study differentiability properties of the map
$T\mapsto\phi(T)$, where $\phi$ is a given function in the disk-algebra and $T$
ranges over the set of contractions on Hilbert space. We obtain sharp
conditions (in terms of Besov spaces) for differentiability and existence of
higher derivatives. We also find explicit formulae for directional derivatives
(and higher derivatives) in terms of double (and multiple) operator integrals
with respect to semi-spectral measures.


title: Structure of parton showers including quantum interference

abstract:
  It is useful to describe a leading order parton shower as the solution of a
linear equation that specifies how the state of the partons evolves. This
description involves an essential approximation of a strong ordering of
virtualities as the shower progresses from a hard interaction to softer
interactions. If this is to be the only approximation, then the partons should
carry color and spin and quantum interference graphs should be included. We
explain how the evolution equation for this kind of a shower can be formulated.
We discuss briefly our efforts to implement this evolution equation
numerically.


title:
Effect of pressure on the superconducting critical temperature of
  La[O_{0.89}F_{0.11}]FeAs and Ce[O_{0.88}F_{0.12}]FeAs

abstract:
  We have performed several high-pressure resistivity experiments on the
recently discovered superconductors La[O_{0.89}F_{0.11}]FeAs and
Ce[O_{0.88}F_{0.12}]FeAs. At ambient pressure, these materials have
superconducting onset temperatures T_c of 28 K and 44 K, respectively. While
the T_c of La[O_{0.89}F_{0.11}]FeAs goes through a maximum between 10-68 kbar,
in qualitative agreement with a recent report by Takahashi et al., the T_c of
Ce[O_{0.88}F_{0.12}]FeAs decreases monotonically over the measured pressure
range. At 265 kbar, the T_c of the cerium-based compound has been suppressed
below 1.1 K.


title:
Conditioning on an extreme component: Model consistency with regular
  variation on cones

abstract:
  Multivariate extreme value theory assumes a multivariate domain of attraction
condition for the distribution of a random vector. This necessitates that each
component satisfies a marginal domain of attraction condition. An approximation
of the joint distribution of a random vector obtained by conditioning on one of
the components being extreme was developed by Heffernan and Tawn [12] and
further studied by Heffernan and Resnick [11]. These papers left unresolved the
consistency of different models obtained by conditioning on different
components being extreme and we here provide clarification of this issue. We
also clarify the relationship between these conditional distributions,
multivariate extreme value theory and standard regular variation on cones of
the form $[0,\infty]\times(0,\infty]$.


title: Capacity Bounds for Broadcast Channels with Confidential Messages

abstract:
  In this paper, we study capacity bounds for discrete memoryless broadcast
channels with confidential messages. Two private messages as well as a common
message are transmitted; the common message is to be decoded by both receivers,
while each private message is only for its intended receiver. In addition, each
private message is to be kept secret from the unintended receiver where secrecy
is measured by equivocation. We propose both inner and outer bounds to the rate
equivocation region for broadcast channels with confidential messages. The
proposed inner bound generalizes Csisz\'{a}r and K\"{o}rner's rate equivocation
region for broadcast channels with a single confidential message, Liu {\em et
al}'s achievable rate region for broadcast channels with perfect secrecy,
Marton's and Gel'fand and Pinsker's achievable rate region for general
broadcast channels. Our proposed outer bounds, together with the inner bound,
helps establish the rate equivocation region of several classes of discrete
memoryless broadcast channels with confidential messages, including less noisy,
deterministic, and semi-deterministic channels. Furthermore, specializing to
the general broadcast channel by removing the confidentiality constraint, our
proposed outer bounds reduce to new capacity outer bounds for the discrete
memory broadcast channel.


title:
Fractional phenomena of the spontaneous emission of a two-level atom in
  photonic crystals

abstract:
  We suggest a better mathematical method, fractional calculus, for studying
the behavior of the atom-field interaction in photonic crystals. By studying
the spontaneous emission of an atom in a photonic crystal with one-band
isotropic model, we found that the long-time inducing memory of the spontaneous
emission is a fractional phenomenon. This behavior could be well described by
the fractional calculus. And the results show no steady photon-atom bound state
for the atomic resonant transition frequency lying in the proximity of allowed
band edge which is encountered in the previous study [J. Opt. B: Quantum
Semiclass. Opt. {\bf 5}, R43 (2003)]. The correctness of this result is
validated by the ``cut-off smoothing'' density of photon states (DOS) with
fractional calculus. By obtaining a rigorous solution without the
multiple-valued problem for the system, we show the method of fractional
calculus has logically concise property.


title: Size-sorting dust grains in the surface layers of protoplanetary disks

abstract:
  Aims: We wish to investigate what the effect of dust sedimentation is on the
observed 10 mum feature of protoplanetary disks and how this may affect the
interpretation of the observations.
  Methods: Using a combination of modeling tools, we simulated the
sedimentation of a dust grain size distribution in an axisymmetric 2-D model of
a turbulent protoplanetary disk, and we used a radiative transfer program to
compute the resulting spectra.
  Results: We find that the sedimentation can turn a flat feature into a pointy
one, but only to a limited degree and for a very limited set of particle size
distributions. Only if we have a bimodal size distribution, i.e. a very small
grain population and a bigger grain population, do we find that the
transformation from a flat to a pointy feature upon dust sedimentation is
strong. However, our model shows that, if sedimentation is the sole reason for
the variety of silicate feature strengths observed in protoplanetary disks,
then we would expect to find a correlation such that disks with weak mid- to
far-infrared excess have a stronger 10 mum silicate feature than disks with a
strong mid- to far-infrared excess. If this is contrary to what is observed,
then this would indicate that sedimentation cannot be the main reason for the
variety of 10 mum silicate features observed in protoplanetary disks.


title: Characteristic varieties and logarithmic differential 1-forms

abstract:
  We introduce in this paper a hypercohomology version of the resonance
varieties and obtain some relations to the characteristic varieties of rank one
local systems on a smooth quasi-projective complex variety $M$, see Theorem
(3.1) and Corollaries (3.2) and (4.2). A logarithmic resonance variety is also
considered in Proposition (4.5). As an application, we determine the first
characteristic variety of the configuration space of $n$ distinct labeled
points on an elliptic curve, see Proposition (5.1). Finally, for a logarithmic
one form $\alpha$ on $M$ we investigate the relation between the resonance
degree of $\alpha$ and the codimension of the zero set of $\alpha$ on a good
compactification of $M$, see Corollary (1.1). This question was inspired by the
recent work by D. Cohen, G. Denham, M. Falk and A. Varchenko.


title: Theoretical Developments in SUSY

abstract:
  In this talk I review three topics: (i) Heterotic strings from N=1 gauge
theories; (ii) Planar equivalence and emergent center symmetry in QCD-like
theories; (iii) Exact result for gluon scattering amplitudes in N=4 (dual
conformality).


title:
Embedded clusters in NGC1808 central starburst - Near-infrared imaging
  and spectroscopy

abstract:
  In the course of a mid-infrared imaging campaign of close-by active galaxies,
we discovered the mid-infrared counterparts of bright compact radio sources in
the central star-forming region of NGC1808. We aim at confirming that these
sources are deeply embedded, young star clusters and at deriving some of their
intrinsic properties. To complement the mid-infrared data, we have collected a
set of near-infrared data with ISAAC at the VLT: J, Ks, and L' images, as well
as low-resolution, long-slit spectra for three of the sources. Surprisingly,
the new images unveil a near-infrared counterpart for only one of the
mid-infrared/radio sources, namely M8 in the L' band. All the other sources are
so deeply embedded that their emission does not pop out above an extended
diffuse near-infrared emission. The near-infrared spectra of the sources look
alike, with intense, ionised hydrogen lines. This supports the interpretation
of these sources in terms of embedded young clusters. We derive extinctions and
ionising photon production rates for two of the clusters.


title:
A mixed discontinuous/continuous finite element pair for shallow-water
  ocean modelling

abstract:
  We introduce a mixed discontinuous/continuous finite element pair for ocean
modelling, with continuous quadratic pressure/layer depth and discontinuous
velocity. We investigate the finite element pair applied to the linear
shallow-water equations on an f-plane. The element pair has the property that
all geostrophically balanced states which strongly satisfy the boundary
conditions have discrete divergence equal to exactly zero and hence are exactly
steady states of the discretised equations. This means that the finite element
pair has excellent geostrophic balance properties. We illustrate these
properties using numerical tests and provide convergence calculations which
show that the discretisation has quadratic errors, indicating that the element
pair is stable.


title:
Relativistic, QED and nuclear effects in highly charged ions revealed by
  resonant electron-ion recombination in storage rings

abstract:
  Dielectronic recombination (DR) of few-electron ions has evolved into a
sensitive spectroscopic tool for highly charged ions. This is due to
technological advances in electron-beam preparation and ion-beam cooling
techniques at heavy-ion storage rings. Recent experiments prove unambiguously
that DR collision spectroscopy has become sensitive to 2nd order QED and to
nuclear effects. This review discusses the most recent developments in
high-resolution spectroscopy of low-energy DR resonances, experimental studies
of KLL DR of very heavy hydrogenlike ions, isotope shift measurements of DR
resonances, and the experimental determination of hyperfine induced decay rates
in divalent ions utilizing DR.


title: Kaonic Nuclear Systems KbarN and KbarNN as Decaying States

abstract:
  The formation spectra of model KbarN and KbarNN systems formed by (K-, n)
reactions are investigated in order to obtain a theoretical basis for a proper
interpretation of experimental data concerning kaonic nuclear quasi-bound
states. It has been clarified that the experimentally observable kaonic nuclear
state K-pp should be regarded as the decaying state introduced by
Kapur-Peierls, which is different from the pole state solution of the Faddeev
equation.


title:
Configuration mixing of angular-momentum and particle-number projected
  triaxial HFB states using the Skyrme energy density functional

abstract:
  We present a method based on mean-field states generated by triaxial
quadrupole constraints which are projected on particle number and angular
momentum and mixed by the generator coordinate method on the quadrupole moment.
This method is equivalent to a seven-dimensional GCM calculation, mixing all
five degrees of freedom of the quadrupole operator and the gauge angles for
protons and neutrons. A first application to Mg24 permits to analyze in detail
the effects of triaxial deformations and of K-mixing.


title: Unquenched flavors in the Klebanov-Strassler theory

abstract:
  We present an analytic solution of type IIB supergravity plus D7-branes,
describing the addition of any number of flavors to the Klebanov-Strassler
background. The dual field theory and its self-similar RG flow, described by a
cascade of Seiberg dualities also in the presence of flavors, are discussed.
The solution indicates that the dual gauge theory enjoys a duality wall in the
UV. We stress the correspondence between Seiberg duality on the field theory
side, and large gauge transformations on the RR and NSNS potentials on the
gravity side. This contribution is mostly based on arxiv:0706.1238.


title: Renormalization Hopf algebras and combinatorial groups

abstract:
  These are the notes of five lectures given at the Summer School {\em
Geometric and Topological Methods for Quantum Field Theory}, held in Villa de
Leyva (Colombia), July 2--20, 2007. The lectures are meant for graduate or
almost graduate students in physics or mathematics. They include references,
many examples and some exercices. The content is the following.
  The first lecture is a short introduction to algebraic and proalgebraic
groups, based on some examples of groups of matrices and groups of formal
series, and their Hopf algebras of coordinate functions.
  The second lecture presents a very condensed review of classical and quantum
field theory, from the Lagrangian formalism to the Euler-Lagrange equation and
the Dyson-Schwinger equation for Green's functions. It poses the main problem
of solving some non-linear differential equations for interacting fields.
  In the third lecture we explain the perturbative solution of the previous
equations, expanded on Feynman graphs, in the simplest case of the scalar
$\phi^3$ theory.
  The forth lecture introduces the problem of divergent integrals appearing in
quantum field theory, the renormalization procedure for the graphs, and how the
renormalization affects the Lagrangian and the Green's functions given as
perturbative series.
  The last lecture presents the Connes-Kreimer Hopf algebra of renormalization
for the scalar theory and its associated proalgebraic group of formal series.


title: On the classical equivalence of superstring field theories

abstract:
  We construct mappings that send solutions of the cubic and non-polynomial
open superstring field theories to each other. We prove that the action is
invariant under the maps and that gauge orbits are mapped into gauge orbits. It
follows that the perturbative spectrum around solutions is the same in both
theories. The mappings also preserve the string field reality condition.
  We generalize to the cases of a non-BPS D-brane and of multi-D-brane systems.
We analyze the recently found analytical solutions of the cubic action, both in
the BPS sector and the non-BPS sector and show that they span a one parameter
family of solutions with empty cohomology and identical action, which suggests
that they are gauge equivalent. We write the gauge transformations relating
these solutions explicitly. This seems to suggest that open superstring field
theory is able to describe a vacuum solution even around a BPS D-brane.


title: A Spin Chain from String Theory

abstract:
  We study the semiclassical spectrum of bosonic string theory on AdS_3 x S^1
in the limit of large AdS angular momentum. At leading semiclassical order,
this is a subsector of the IIB superstring on AdS_5 x S^5. The theory includes
strings with K spikes which approach the boundary in this limit. We show that,
for all K, the spectrum of these strings exactly matches that of the
corresponding operators in the dual gauge theory up to a single universal
prefactor which can be identified with the cusp anomalous dimension. We propose
a precise map between the dynamics of the spikes and the classical SL(2,R) spin
chain which arises in the large-spin limit of N=4 Super Yang-Mills theory.


title:
Effect of anisotropy on the ground-state magnetic ordering of the
  spin-one quantum $J_{1}^{XXZ}$--$J_{2}^{XXZ}$ model on the square lattice

abstract:
  We study the zero-temperature phase diagram of the
$J_{1}^{XXZ}$--$J_{2}^{XXZ}$ Heisenberg model for spin-1 particles on an
infinite square lattice interacting via nearest-neighbour ($J_1 \equiv 1$) and
next-nearest-neighbour ($J_2 > 0$) bonds. Both bonds have the same $XXZ$-type
anisotropy in spin space. The effects on the quasiclassical N\'{e}el-ordered
and collinear stripe-ordered states of varying the anisotropy parameter
$\Delta$ is investigated using the coupled cluster method carried out to high
orders. By contrast with the spin-1/2 case studied previously, we predict no
intermediate disordered phase between the N\'{e}el and collinear stripe phases,
for any value of the frustration $J_2/J_1$, for either the $z$-aligned ($\Delta
> 1$) or $xy$-planar-aligned ($0 \leq \Delta < 1$) states. The quantum phase
transition is determined to be first-order for all values of $J_2/J_1$ and
$\Delta$. The position of the phase boundary $J_{2}^{c}(\Delta)$ is determined
accurately. It is observed to deviate most from its classical position $J_2^c =
{1/2}$ (for all values of $\Delta > 0$) at the Heisenberg isotropic point
($\Delta = 1$), where $J_{2}^{c}(1) = 0.55 \pm 0.01$. By contrast, at the XY
isotropic point ($\Delta = 0$), we find $J_{2}^{c}(0) = 0.50 \pm 0.01$. In the
Ising limit ($\Delta \to \infty$) $J_2^c \to 0.5$ as expected.


title: POLAR Investigation of the Sun - POLARIS

abstract:
  The POLAR Investigation of the Sun (POLARIS) mission uses a combination of a
gravity assist and solar sail propulsion to place a spacecraft in a 0.48 AU
circular orbit around the Sun with an inclination of 75 degrees with respect to
solar equator. This challenging orbit is made possible by the challenging
development of solar sail propulsion. This first extended view of the
high-latitude regions of the Sun will enable crucial observations not possible
from the ecliptic viewpoint or from Solar Orbiter. While Solar Orbiter would
give the first glimpse of the high latitude magnetic field and flows to probe
the solar dynamo, it does not have sufficient viewing of the polar regions to
achieve POLARIS' primary objective : determining the relation between the
magnetism and dynamics of the Sun's polar regions and the solar cycle.


title: Beauty photoproduction using decays into electrons at HERA

abstract:
  Photoproduction of beauty quarks in events with two jets and an electron
associated with one of the jets has been studied with the ZEUS detector at HERA
using an integrated luminosity of 120pb^-1. The fractions of events containing
b quarks, and also of events containing c quarks, were extracted from a
likelihood fit using variables sensitive to electron identification as well as
to semileptonic decays. Total and differential cross sections for beauty and
charm production were measured and compared with next-to-leading-order QCD
calculations and Monte Carlo models.


title:
An intense state of hard X-ray emission of Cyg X-1 observed by INTEGRAL
  coincident with TeV measurements

abstract:
  We present INTEGRAL light curves and spectra of the black-hole binary Cyg X-1
during a bright event that occurred in 2006 September, and which was
simultaneous with a detection at 0.15-1 TeV energies by the MAGIC telescope. We
analyse the hard X-ray emission from 18 to 700 keV with the INTEGRAL data taken
on 2006 September 24-26. We present the light curves and fit the high energy
spectrum with various spectral models. Despite variations in the flux by a
factor of ~2 in the the 20-700 keV energy band, the shape of the energy
spectrum remained remarkably stable. It is very well represented by an e-folded
power law with the photon index of 1.4 and a high energy cut-off around 130-140
keV. The spectrum is also well described by thermal Comptonisation including a
moderate reflection component, with a reflectionamplitude R around 0.4. The
temperature of the hot Comptonising electrons is ~70 keV and their Thomson
optical depth is ~2.5. These spectral properties are typical of those observed
in the low/hard state. This shows that Cyg X-1 may stay in the low hard state
at least up to the flux level of 2 Crab, which corresponds to ~2-3 percent of
the Eddington luminosity. It is the first time a persistent high-mass
black-hole binary is observed at a few percent of the Eddington luminosity with
a stable low/hard state spectrum over a period of a few days. The TeV detection
coincides with the peak of a small X-ray flare just after a very fast rise in
hard X-ray flux. In contrast, the source remained undetected by MAGIC at the
peak of a larger X-ray flare occurring one day later and corresponding to the
maximum of the X-ray luminosity of the whole outburst. We do not find any
obvious correlation between the X-ray and TeV emission.


title:
Holographic generation of complex fields with spatial light modulators:
  application to quantum key distribution

abstract:
  There has been considerable interest recently in the generation of azimuthal
phase functions associated with photon orbital angular momentum (OAM) for
high-dimensional quantum key distribution (QKD). The generation of secure
quantum keys requires not only this pure phase basis, but also additional bases
comprised of orthonormal superposition states formed from the pure states.
These bases are also known as mutually unbiased bases (MUBs) and include
quantum states whose wave functions are modulated in both phase and amplitude.
While modulo 2\pi optical path control with high-resolution spatial light
modulators (SLMs) is well suited to creating the azimuthal phases associated
with the pure states, it does not introduce the amplitude modulation associated
with the MUB superposition states. Using computer-generated holography (CGH)
with the Leith-Upatnieks approach to hologram recording however, both phase and
amplitude modulation can be achieved. This paper presents a description of the
OAM states of a 3-dimensional MUB system and analyzes the construction of these
states via CGH with a phase modulating SLM. The effects of phase holography
artifacts on quantum-state generation are quantified and a prescription for
avoiding these artifacts by preconditioning the hologram function is presented.
Practical effects associated with spatially isolating the first-order
diffracted field are also quantified and a demonstration utilizing a liquid
crystal SLM is presented.


title:
The Littlest Higgs Model with T-Parity Facing CP-Violation in B_s -
  anti-B_s Mixing

abstract:
  The non-minimal flavour violating interactions of mirror quarks and new heavy
gauge bosons in the Littlest Higgs model with T-parity (LHT) give rise to
naturally large CP-violating effects in the B_s system. In view of a large new
CP phase in B_s - anti-B_s mixing hinted by the CDF and D0 data and the recent
UTfit analysis, we update our 2006 analysis of particle-antiparticle mixing and
rare K and B decays in the LHT model, using the most recent values of a number
of input parameters and performing a more careful error analysis. We find that
the CP-asymmetry S_{psi phi} can easily reach values ~ 0.15-0.20, compared to
the SM value ~ 0.04, while higher values are rather unlikely though not
excluded. Large enhancements are also possible in the branching ratios for K_L
-> pi0 nu anti-nu, K+ -> pi+ nu anti-nu and K_L -> pi0 l+ l- with much more
modest effects in B_{s,d} -> mu+ mu-. We perform a detailed study of
correlations between the latter decays and S_{psi phi} as well as of the
correlation between S_{psi phi} and S_{psi K_S}. We also point out that the
possible tension between epsilon_K and the tree level CKM determination
recently hinted by various analyses can easily be resolved in the LHT model.


title:
Confidentiality, Integrity and High Availability with Open Source IT
  green

abstract:
  This paper presents elements that form the structure of a network of data
using secure stable and mature technologies that meet the requirement of having
code free. The principle would be conflicting code open Tuesday where he wants
to keep maximum control over the data but is already evidence that open source
does not hide the famous backdoor possible in closed systems code.
  Basearemos this work experience gained in a real environment and using
paravirtualization to show a situation more critical and now real in most
companies, the virtualization of servers.


title:
Instabilities of MHD Waves Produced by Coupling of Rotation and Gradient
  of Magnetic Field and its Possible Application in the Galactic Central Region

abstract:
  An analysis of MHD wave propagating in a gravitating and rotating medium
permeated by non-uniform magnetic field has been done. It has been found that
the Gradient of Magnetic Field when coupled with Rotation becomes capable to
generate few instabilities (Temporal or Spatial) leading to the damping or
amplification of MHD waves. The Jean's criterion is not sufficient for
stability always. Rather, the waves will suffer instability unless their wave
length (frequency) is less (greater) than certain critical values. Otherwise,
those will smoothly propagate outward. Out of different scenarioes depending on
the direction of the magnetic field, its gradient, rotation and wave
propagation three important Special Cases have been discussed and different
stability criteria have been derived.
  Finally, using the above theory we have obtained the stability/instability
criteria for the waves moving parallel and perpendicular to the galactic plane
in the Core and Periphery of the Central Region of Galaxy (C.R.G.) due to the
coupled action of Rotation and Non-Uniform Magnetic field. The possibility of
heating or occuring diffused condition inside the central region by MHD waves
or smooth propagation of these waves (under some restrictions) through the
C.R.G. has been briefly discussed. The numerical values of the parameters of
those waves for instabilities or smooth propagation have been estimated
roughly. One may find some clues for the formation of Halo and Spiral Arms.


title:
Eikonal analysis of Coulomb distortion in quasi-elastic electron
  scattering

abstract:
  An eikonal expansion is used to provide systematic corrections to the eikonal
approximation through order $1/k^2$, where $k$ is the wave number. Electron
wave functions are obtained for the Dirac equation with a Coulomb potential.
They are used to investigate distorted-wave matrix elements for quasi-elastic
electron scattering from a nucleus. A form of effective-momentum approximation
is obtained using trajectory-dependent eikonal phases and focusing factors.
Fixing the Coulomb distortion effects at the center of the nucleus, the
often-used ema approximation is recovered. Comparisons of these approximations
are made with full calculations using the electron eikonal wave functions. The
ema results are found to agree well with the full calculations.


title: Visualizing Astrophysical N-body Systems

abstract:
  I begin with a brief history of N-body simulation and visualization and then
go on to describe various methods for creating images and animations of modern
simulations in cosmology and galactic dynamics. These techniques are
incorporated into a specialized particle visualization software library called
MYRIAD that is designed to render images within large parallel N-body
simulations as they run. I present several case studies that explore the
application of these methods to animations of star clusters, interacting
galaxies and cosmological structure formation.


title:
The photospheric solar oxygen project: I. Abundance analysis of atomic
  lines and influence of atmospheric models

abstract:
  The solar oxygen abundance has undergone a major downward revision in the
last decade, the most noticeable one being the update including 3D
hydrodynamical simulations to model the solar photosphere. Up to now, such an
analysis has been carried out only by one group using one
radiation-hydrodynamics code. We investigate the photospheric oxygen abundance
considering lines from atomic transitions. We also consider the relationship
between the solar model used and the resulting solar oxygen abundance, to
understand whether the downward abundance revision is specifically related to
3D hydrodynamical effects. We perform a new determination of the solar
photospheric oxygen abundance by analysing different high-resolution high
signal-to-noise ratio atlases of the solar flux and disc-centre intensity
making use of the latest generation of CO5BOLD 3D solar model atmospheres. We
find 8.73 < logNoxygen/Nhydrogen +12 < 8.79. The lower and upper value
represent extreme assumptions on the role of collisional excitation and
ionisation by neutral hydrogen for the NLTE level populations of neutral
oxygen. The error of our analysis is +-0.04 +- 0.03 dex, the last being related
to NLTE corrections, the first error to any other effect. 3D ``granulation
effects'' do not play a decisive role in lowering the oxygen abundance. Our
recommended value, considering our present ignorance of the role of collisions
with hydrogen atoms on the NLTE level populations of oxygen, is
log(Noxygen/Nhydrogen) = 8.76 +- 0.07. The reasons which have led to lower O
abundances in the past are identified as (1) the lower equivalent widths
adopted, and (2) the choice of neglecting collisions with hydrogen atoms in the
statistical equilibrium calculations for oxygen.


title: The hypergeneralized Heun equation in QFT in curved space-times

abstract:
  In this article we show for the first time the role played by the
hypergeneralized Heun equation (HHE) in the context of Quantum Field Theory in
curved space-times. More precisely, we find suitable transformations relating
the separated radial and angular parts of a massive Dirac equation in the
Kerr-Newman-deSitter metric to a HHE.


title: Testing Alternative Theories of Dark Matter with the CMB

abstract:
  We propose a method to study and constrain modified gravity theories for dark
matter using CMB temperature anisotropies and polarization. We assume that the
theories considered here have already passed the matter power-spectrum test of
large-scale structure. With this requirement met, we show that a modified
gravity theory can be specified by parametrizing the time evolution of its
dark-matter density contrast, which is completely controlled by the dark matter
stress history. We calculate how the stress history with a given
parametrization affects the CMB observables, and a qualitative discussion of
the physical effects involved is supplemented with numerical examples. It is
found that, in general, alternative gravity theories can be efficiently
constrained by the CMB temperature and polarization spectra. There exist,
however, special cases where modified gravity cannot be distinguished from the
CDM model even by using both CMB and matter power spectrum observations, nor
can they be efficiently restricted by other observables in perturbed
cosmologies. Our results show how the stress properties of dark matter, which
determine the evolutions of both density perturbations and the gravitational
potential, can be effectively investigated using just the general conservation
equations and without assuming any specific theoretical gravitational theory
within a wide class.


title:
Numerical Study of Energy Loss by a Nanomechanical Oscillator Coupled to
  a Cooper Pair Box

abstract:
  We calculate the dynamics of a nanomechanical oscillator (NMO) coupled
capacitively to a Cooper pair box (CPB), by solving a stochastic Schrodinger
equation with two Lindblad operators. Both the NMO and the CPB are assumed
dissipative, and the coupling is treated within the rotating wave
approximation. We show numerically that, if the CPB decay time is smaller than
the NMO decay time, the coupled NMO will lose energy faster, and the coupled
CPB more slowly, than do the uncoupled NMO and CPB. The results show that the
efficiency of energy loss by an NMO can be substantially increased if the NMO
is coupled to a CPB.


title:
The energy partitioning of non-thermal particles in a plasma: or the
  Coulomb logarithm revisited

abstract:
  The charged particle stopping power in a highly ionized and weakly to
moderately coupled plasma has been calculated to leading and next-to-leading
order by Brown, Preston, and Singleton (BPS). After reviewing the main ideas
behind this calculation, we use a Fokker-Planck equation derived by BPS to
compute the electron-ion energy partitioning of a charged particle traversing a
plasma. The motivation for this application is ignition for inertial
confinement fusion -- more energy delivered to the ions means a better chance
of ignition, and conversely. It is therefore important to calculate the
fractional energy loss to electrons and ions as accurately as possible, as this
could have implications for the Laser Megajoule (LMJ) facility in France and
the National Ignition Facility (NIF) in the United States. The traditional
method by which one calculates the electron-ion energy splitting of a charged
particle traversing a plasma involves integrating the stopping power dE/dx.
However, as the charged particle slows down and becomes thermalized into the
background plasma, this method of calculating the electron-ion energy splitting
breaks down. As a result, the method suffers a systematic error of order T/E0,
where T is the plasma temperature and E0 is the initial energy of the charged
particle. In the case of DT fusion, for example, this can lead to uncertainties
as high as 10% or so. The formalism presented here is designed to account for
the thermalization process, and in contrast, it provides results that are
near-exact.


title:
A cell complex structure for the space of heteroclines for a semilinear
  parabolic equation

abstract:
  It is well known that for many semilinear parabolic equations there is a
global attractor which has a cell complex structure with finite dimensional
cells. Additionally, many semilinear parabolic equations have equilibria with
finite dimensional unstable manifolds. In this article, these results are
unified to show that for a specific parabolic equation on an unbounded domain,
the space of heteroclinic orbits has a cell complex structure with finite
dimensional cells. The result depends crucially on the choice of spatial
dimension and the degree of the nonlinearity in the parabolic equation, and
thereby requires some delicate treatment.


title: Non-Markovian Dissipative Semiclassical Dynamics

abstract:
  The exact stochastic decomposition of non-Markovian dissipative quantum
dynamics is combined with the time-dependent semiclassical initial value
formalism. It is shown that even in the challenging regime of moderate friction
and low temperatures, where non-Markovian effects are substantial, this
approach allows for the accurate description of dissipative dynamics in
anharmonic potentials over many oscillation periods until thermalization is
reached. The problem of convergence of the stochastic average at long times,
which plagues full quantum mechanical implementations, is avoided through a
joint sampling of the stochastic noise and the semiclassical phase space
distribution.


title: Statistical properties of chaotic binary sequences

abstract:
  Mean value and cross-covariance function of chaotic binary sequences are
evaluated for chaotic maps with specific properties. We also take into account
the effect of fixed- and floating-point representations on statistical
properties of chaotic generators. Thus, one is able to obtain possible
candidates for pseudo-random binary sequences generation. Results of
statistical tests applied to chaotic binary sequences are presented. The
chaotic binary sequences thus obtained could be used for security improvement
in IEEE 802.11 standard.


title: Forward Physics at the LHC

abstract:
  The CMS/TOTEM and ATLAS collaborations carry out a program of forward physics
with several near-beam detectors extending their coverage to high
pseudorapidities. This instrumentation includes calorimeters (CASTOR and ZDC),
tracking devices (TOTEM T1 and T2), proton taggers (Roman Pots and FP420), and
instrumentation dedicated to luminosity monitoring and normalisation. A rich
physics program is accessible, including soft QCD interactions, Diffraction,
photon-induced physics and luminosity measurements.


title: The generalised scaling function: a note

abstract:
  A method for determining the generalised scaling function(s) arising in the
high spin behaviour of long operator anomalous dimensions in the planar $sl(2)$
sector of ${\cal N}=4$ SYM is proposed. The all-order perturbative expansion
around the strong coupling is detailed for the prototypical third and fourth
scaling functions, showing the emergence of the O(6) Non-Linear Sigma Model
mass-gap from different SYM 'mass' functions. Remarkably, only the fourth one
gains contribution from the non-BES reducible densities and also shows up, as
first, NLSM interaction and specific model dependence. Finally, the computation
of the $n$-th generalised function is sketched and might be easily finalised
for checks versus the computations in the sigma model or the complete string
theory.


title:
First VLTI infrared spectro-interferometry on GCIRS 7 - Characterizing
  the prime reference source for Galactic center observations at highest
  angular resolution

abstract:
  Investigating the environment of the massive black hole SgrA* at the center
of the Galaxy requires the highest angular resolution available to avoid source
confusion and to study the physical properties of the individual objects.
GCIRS7 has been used as wavefront and astrometric reference. Our studies
investigate, for the first time, its properties at 2&10um using VLTI/AMBER and
MIDI. We aim at analyzing the suitability of IRS7 as an IF-phase-reference for
the upcoming generation of dual-field facilities at optical interferometers. We
observed with (R~30) and 50m (proj.) baseline, resulting in 9 and 45mas
resolution for NIR and MIR, resp. The first K-band fringe detection of a GC
star suggests that IRS7 could be marginally resolved at 2um, which would imply
that the photosphere of the supergiant is enshrouded by a molecular and dusty
envelope. At 10um, IRS7 is strongly resolved with a visibility of approximately
0.2. The MIR is dominated by moderately warm (200 K), extended dust, mostly
distributed outside of a radius of about 120 AU (15 mas) around the star. A
deep 9.8-silicate absorption in excess of the usual extinction law with respect
to the NIR extinction has been found. This confirms recent findings of a
relatively enhanced, interstellar 9.8-silicate absorption with respect to the
NIR extinction towards another star in the central arcsec, suggesting an
unusual dust composition in that region. Our VLTI observations show that
interferometric NIR phase-referencing experiments with mas resolution using
IRS7 as phase-reference appear to be feasible, but more such studies are
required to definitely characterize the close environment around this star. We
demonstrate that interferometry is required to resolve the innermost
environment of stars at the Galactic center.


title: On the ambiguities in the effective action in Lorentz-violating gravity

abstract:
  We investigate the occurrence of ambiguities for Lorentz-violating
gravitational Chern-Simons term. It turns out that this term is accompanied by
a coefficient depending on an undetermined parameter, due to an arbitrariness
in the choice of the conserved current.


title: The integrable O(6) model and the correspondence: checks and predictions

abstract:
  We exactly compute the energy density of the integrable O(n) non-linear sigma
model as a convergent series. This series is specifically analysed for the very
important O(6) symmetry, since it was suggested to result as a peculiar limit
of the AdS string theory by Alday and Maldacena [1]. In this respect, the O(6)
model gives also refined confirmations and predictions once compared with the
SYM Bethe Ansatz [2,3].


title: The PHOBOS Glauber Monte Carlo

abstract:
  ``Glauber'' models are used to calculate geometric quantities in the initial
state of heavy ion collisions, such as impact parameter, number of
participating nucleons and initial eccentricity. The four RHIC experiments have
different methods for Glauber Model calculations, leading to similar results
for various geometric observables. In this document, we describe an
implementation of the Monte Carlo based Glauber Model calculation used by the
PHOBOS experiment. The assumptions that go in the calculation are described. A
user's guide is provided for running various calculations.


title: Cobordism invariance of the family index

abstract:
  We give a K-theory proof of the invariance under cobordism of the family
index. We consider elliptic pseudodifferential families on a continuous fibre
bundle with smooth fibres over a compact base space B, and define a notion of
cobordant families using K^1-groups on fibrations with boundary. We show that
the index of two such families is the same using properties of the push-forward
map in K-theory to reduce it to families on B x R^n.


title:
Parameterization of Theoretical Methods in the Calculation of
  Nano-expulsion Energies

abstract:
  The present work encompasses an investigation of the adsorption properties of
small dimer species onto a zigzag single walled carbon nanotube (ZNT for
short). To perform this analysis we have considered the zigzag (8, 0) system
with a length of 13.5 angstroms that has a diameter of 6.3 angstroms. Various
theoretical DFT and ab initio approaches were used to attempt to parameterize
an ideal method for the calculation of expulsion energies for nanotube species.


title: The Fast Fourier Transform Telescope

abstract:
  We propose an all-digital telescope for 21 cm tomography, which combines key
advantages of both single dishes and interferometers. The electric field is
digitized by antennas on a rectangular grid, after which a series of Fast
Fourier Transforms recovers simultaneous multifrequency images of up to half
the sky. Thanks to Moore's law, the bandwidth up to which this is feasible has
now reached about 1 GHz, and will likely continue doubling every couple of
years. The main advantages over a single dish telescope are cost and orders of
magnitude larger field-of-view, translating into dramatically better
sensitivity for large-area surveys. The key advantages over traditional
interferometers are cost (the correlator computational cost for an N-element
array scales as N log N rather than N^2) and a compact synthesized beam. We
argue that 21 cm tomography could be an ideal first application of a very large
Fast Fourier Transform Telescope, which would provide both massive sensitivity
improvements per dollar and mitigate the off-beam point source foreground
problem with its clean beam. Another potentially interesting application is
cosmic microwave background polarization.


title:
Time-Dependent Models of Accretion Disks Formed from Compact Object
  Mergers

abstract:
  We present time-dependent models of the accretion disks created during
compact object mergers, focusing on the energy available from accretion at late
times and the composition of the disk and its outflows. We calculate the
dynamics near the outer edge of the disk, which contains the majority of the
mass and sets the accretion rate onto the central black hole. This allows us to
follow the evolution over much longer timescales than current hydrodynamic
simulations. At late times the disk becomes advective and its properties
asymptote to self-similar solutions with accretion rate dM/dt ~ t^(-4/3)
(neglecting outflows). This late-time accretion can in principle provide
sufficient energy to power the late-time activity observed from some
short-duration gamma-ray bursts (GRBs). However, because outflows during the
advective phase unbind the majority of the remaining mass, it is difficult for
the remnant disk alone to produce significant accretion power well beyond the
onset of the advective phase. Unless the viscosity is quite low (alpha ~1e-3),
this occurs before the start of observed flaring at ~ 30 s; continued mass
inflow thus appears required to explain the late-time activity from short GRBs.
We show that the composition of the disk freezes-out relatively neutron-rich
(electron fraction Ye ~ 0.3). Roughly 1e-2 Msun of this neutron-rich material
is ejected by winds at late times. During earlier, neutrino-cooled phases of
accretion, neutrino irradiation of the disk produces a wind with Ye ~ 0.5,
which synthesizes at most ~ 1e-3 Msun of Ni56. We highlight what conditions are
favorable for Ni56 production and predict, in the best cases, optical and
infrared transients peaking ~ 0.5-2 days after the burst, with fluxes a factor
of ~ 10 below the current observational limits.


title:
The Dark Matter Annihilation Signal from Galactic Substructure:
  Predictions for GLAST

abstract:
  We present quantitative predictions for the detectability of individual
Galactic dark matter subhalos in gamma-rays from dark matter pair annihilations
in their centers. Our method is based on a hybrid approach, employing the
highest resolution numerical simulations available (including the recently
completed one billion particle Via Lactea II simulation) as well as analytical
models for the extrapolation beyond the simulations' resolution limit. We
include a self-consistent treatment of subhalo boost factors, motivated by our
numerical results, and a realistic treatment of the expected backgrounds that
individual subhalos must outshine. We show that for reasonable values of the
dark matter particle physics parameters (M_X ~ 50 - 500 GeV and <sigma*v> ~
10^-26 - 10^-25 cm^3/s) GLAST may very well discover a few, even up to several
dozen, such subhalos, at 5 sigma significance, and some at more than 20 sigma.
We predict that the majority of luminous sources would be resolved with GLAST's
expected angular resolution. For most observer locations the angular
distribution of detectable subhalos is consistent with a uniform distribution
across the sky. The brightest subhalos tend to be massive (median Vmax of 24
km/s) and therefore likely hosts of dwarf galaxies, but many subhalos with Vmax
as low as 5 km/s are also visible. Typically detectable subhalos are 20 - 40
kpc from the observer, and only a small fraction are closer than 10 kpc. The
total number of observable subhalos has not yet converged in our simulations,
and we estimate that we may be missing up to 3/4 of all detectable subhalos.