title:
Forces and momenta caused by electromagnetic waves in magnetoelectric
  media

abstract:
  We analyse the propagation of electromagnetic waves in magnetoelectric media.
Recently, Feigel has predicted that such a medium may ``extract momentum from
vacuum" in the sense that the total momentum of the virtual waves (vacuum
fluctuations of the electromagnetic field) is nontrivial. Our aim is to check
the feasibility of this effect. The crucial point in our study is an assumption
of the finite size of the magnetoelectric sample, which allows us to reduce the
calculation of the momenta and forces of the electromagnetic waves acting on
the sample to the vacuum region outside of the medium. In this framework, we
demonstrate that, in contrast to Feigel, the total force caused by the virtual
is zero, with an appropriate count of the modes that should be taken into
account in this effect. Furthermore, we find that the two irreducible parts of
the magnetoelectric matrix behave differently in the possible Feigel effect.
Going beyond the original scheme of the virtual electromagnetic waves, we
propose an experimental scheme which is suitable for the measurement of the
magnetoelectric susceptibilities of the medium with the help of real
electromagnetic waves.

categories: physics.class-ph cond-mat.other gr-qc physics.gen-ph


title: Quantum phases of mixtures of atoms and molecules on optical lattices

abstract:
  We investigate the phase diagram of a two-species Bose-Hubbard model
including a conversion term, by which two particles from the first species can
be converted into one particle of the second species, and vice-versa. The model
can be related to ultra-cold atom experiments in which a Feshbach resonance
produces long-lived bound states viewed as diatomic molecules. The model is
solved exactly by means of Quantum Monte Carlo simulations. We show than an
"inversion of population" occurs, depending on the parameters, where the second
species becomes more numerous than the first species. The model also exhibits
an exotic incompressible "Super-Mott" phase where the particles from both
species can flow with signs of superfluidity, but without global supercurrent.
We present two phase diagrams, one in the (chemical potential, conversion)
plane, the other in the (chemical potential, detuning) plane.


title:
LAMBDA: Large Area Modular BaF2 Detector Array for the measurement of
  high energy gamma rays

abstract:
  A large BaF2 detector array along with its dedicated CAMAC electronics and
VME based data acquisition system has been designed, constructed and installed
successfully at VECC, Kolkata for studying high energy gamma rays (E>8 MeV).
The array consists of 162 detector elements. The detectors were fabricated from
bare barium fluoride crystals (each measuring 35 cm in length and having
cross-sectional area of 3.5 cm X 3.5 cm X 35.0 cm). The basic properties of the
detectors (energy resolution, time resolution, efficiency, uniformity, fast to
slow ratio etc.) were studied exhaustively. Complete GEANT3 monte carlo
simulations were performed to optimize the detector design and also to generate
the response function. The detector system has been used successfully to
measure high energy photons from 113Sb, formed by bombarding 145 and 160 MeV
20Ne beams on a 93Nb target. The measured experimental spectra are in good
agreement with those from a modified version of the statistical model code
CASCADE. In this paper, we present the complete description of this detector
array along with its in-beam performance.


title:
Dielectric Susceptibility and Heat Capacity of Ultra-Cold Glasses in
  Magnetic Field

abstract:
  Recent experiments demonstrated unexpected, even intriguing properties of
certain glassy materials in magnetic field at low temperatures. We have studied
the magnetic field dependence of the static dielectric susceptibility and the
heat capacity of glasses at low temperatures. We present a theory in which we
consider the coupling of the tunnelling motion to nuclear quadrupoles in order
to evaluate the static dielectric susceptibility. In the limit of weak magnetic
field we find the resonant part of the susceptibility increasing like $B^2$
while for the large magnetic field it behaves as 1/B. In the same manner we
consider the coupling of the tunnelling motion to nuclear quadrupoles and
angular momentum of tunnelling particles in order to find the heat capacity.
Our results show the Schotky peak for the angular momentum part, and $B^2$
dependence for nuclear quadrupoles part of heat capacity, respectively. We
discuss whether or not this approach can provide a suitable explanation for
such magnetic properties.


title:
Experimental determination of the absorption strength in absorbing
  chaotic cavities

abstract:
  Due to the experimental necessity we present a formula to determine the
absorption strength by power losses inside a chaotic system (cavities, graphs,
acoustic resonators, etc) when the antenna coupling, always present in
experimental measurements, is taken into account. This is done by calculating
the average of the absorption coefficient as a function of the absorption
strength and the coupling of the antenna to the system, in the one channel
case.


title:
The Plancherel Formula for the Universal Covering Group of SL(2,R)
  Revisited

abstract:
  The Plancherel formula for the universal covering group of $SL(2, R)$ derived
earlier by Pukanszky on which Herb and Wolf build their Plancherel theorem for
general semisimple groups is reconsidered. It is shown that a set of unitarily
equivalent representations is treated by these authors as distinct.
Identification of this equivalence results in a Plancherel measure
($s\mathrm{Re}\tanh\pi(s+\frac{i\tau}{2}), 0\leq\tau<1)$ which is different
from the Pukanszky-Herb-Wolf measure ($s\mathrm{Re}\tanh\pi(s+i\tau),
0\leq\tau<1)$.


title:
Dust in the wind: Crystalline silicates, corundum and periclase in PG
  2112+059

abstract:
  We have determined the mineralogical composition of dust in the Broad
Absorption Line (BAL) quasar PG 2112+059 using mid-infrared spectroscopy
obtained with the Spitzer Space Telescope. From spectral fitting of the solid
state features, we find evidence for Mg-rich amorphous silicates with olivine
stoichiometry, as well as the first detection of corundum (Al_2O_3) and
periclase (MgO) in quasars. This mixed composition provides the first direct
evidence for a clumpy density structure of the grain forming region. The
silicates in total encompass 56.5% of the identified dust mass, while corundum
takes up 38 wt.%. Depending on the choice of continuum, a range of mass
fractions is observed for periclase ranging from 2.7% in the most conservative
case to 9% in a less constrained continuum. In addition, we identify a feature
at 11.2 micron as the crystalline silicate forsterite, with only a minor
contribution from polycyclic aromatic hydrocarbons. The 5% crystalline silicate
fraction requires high temperatures such as those found in the immediate quasar
environment in order to counteract rapid destruction from cosmic rays.


title: Functional biases in GRB's spectral parameter correlations

abstract:
  Gamma Ray Bursts (GRBs) show evidence of different spectral shapes, light
curves, duration, host galaxies and they explode within a wide redshift range.
However, the most of them seems to follow very tight correlations among some
observed quantities relating to their energetic. If true, these correlations
have significant implications on burst physics, giving constraints on
theoretical models. Moreover, several suggestions have been made to use these
correlations in order to calibrate GRBs as standard candles and to constrain
the cosmological parameters. We investigate the cosmological relation between
low energy $\alpha$ index in GRBs prompt spectra and the redshift $z$. We
present a statistical analysis of the relation between the total isotropic
energy $E_{iso}$ and the peak energy $E_p$ (also known as Amati relation) in
GRBs spectra searching for possible functional biases. Possible implications on
the $E_{iso}$ vs $E_p$ relation of the $\alpha$ vs $(1+z)$ correlation are
evaluated. We used MonteCarlo simulations and the boostrap method to evaluate
how large are the effects of functional biases on the $E_{iso}$ vs $E_p$. We
show that high values of the linear correlation coefficent, up to about 0.8, in
the $E_{iso}$ vs $E_p$ relation are obtained for random generated samples of
GRBs, confirming the relevance of functional biases. Astrophysical consequences
from $E_{iso}$ vs $E_p$ relation are then to be revised after a more accurate
and possibly bias free analysis.


title:
A System for Predicting Subcellular Localization of Yeast Genome Using
  Neural Network

abstract:
  The subcellular location of a protein can provide valuable information about
its function. With the rapid increase of sequenced genomic data, the need for
an automated and accurate tool to predict subcellular localization becomes
increasingly important. Many efforts have been made to predict protein
subcellular localization. This paper aims to merge the artificial neural
networks and bioinformatics to predict the location of protein in yeast genome.
We introduce a new subcellular prediction method based on a backpropagation
neural network. The results show that the prediction within an error limit of 5
to 10 percentage can be achieved with the system.


title: Recommendation model based on opinion diffusion

abstract:
  Information overload in the modern society calls for highly efficient
recommendation algorithms. In this letter we present a novel diffusion based
recommendation model, with users' ratings built into a transition matrix. To
speed up computation we introduce a Green function method. The numerical tests
on a benchmark database show that our prediction is superior to the standard
recommendation methods.

categories: physics.soc-ph cs.CY cs.IR physics.data-an


title: Precision for B-meson matrix elements

abstract:
  We demonstrate how HQET and the Step Scaling Method for B-physics, pioneered
by the Tor Vergata group, can be combined to reach a further improved
precision. The observables considered are the mass of the b-quark and the
B_s-meson decay constant. The demonstration is carried out in quenched lattice
QCD. We start from a small volume, where one can use a standard O(a)-improved
relativistic action for the b-quark, and compute two step scaling functions
which relate the observables to the large volume ones. In all steps we
extrapolate to the continuum limit, separately in HQET and in QCD for masses
below m_b. The physical point m_b is then reached by an interpolation of the
continuum results in 1/m. The essential, expected and verified, feature is that
the step scaling fuctions have a weak mass-dependence resulting in an easy
interpolation to the physical point. With r_0=0.5fm and the experimental B_s
and K masses as input, we find F_Bs=191(6)MeV and the renormalization group
invariant mass M_b=6.88(10)GeV, translating into m_b(m_b)=4.42(6)GeV in the
MSbar scheme. This approach seems very promising for full QCD.


title: Collider signatures for unparticle

abstract:
  We summarize the works presented in Refs. \cite{1,2} on collider
phenomenology of the unparticle physics associated with an exact scale
invariant sector possessing a non-trivial infrared fixed point at a high energy
scale. We give highlights on the motivations of unparticle and derivation of
the phase space and the unparticle propagator. We study two categories of
phenomenology: (i) real emission of unparticle that gives rise to peculiar
missing energy signatures, and (ii) virtual exchange of unparticle that
interferes with the standard model amplitudes.


title:
Comparison and Combination of State-of-the-art Techniques for
  Handwritten Character Recognition: Topping the MNIST Benchmark

abstract:
  Although the recognition of isolated handwritten digits has been a research
topic for many years, it continues to be of interest for the research community
and for commercial applications. We show that despite the maturity of the
field, different approaches still deliver results that vary enough to allow
improvements by using their combination. We do so by choosing four
well-motivated state-of-the-art recognition systems for which results on the
standard MNIST benchmark are available. When comparing the errors made, we
observe that the errors made differ between all four systems, suggesting the
use of classifier combination. We then determine the error rate of a
hypothetical system that combines the output of the four systems. The result
obtained in this manner is an error rate of 0.35% on the MNIST data, the best
result published so far. We furthermore discuss the statistical significance of
the combined result and of the results of the individual classifiers.


title:
The Chandra Small Magellanic Cloud Wing Survey - the search for X-ray
  Binaries

abstract:
  We have detected 523 sources in a survey of the Small Magellanic Cloud (SMC)
Wing with Chandra. By cross-correlating the X-ray data with optical and
near-infrared catalogues we have found 300 matches. Using a technique that
combines X-ray colours and X-ray to optical flux ratios we have been able to
assign preliminary classifications to 265 of the objects. Our identifications
include four pulsars, one high-mass X-ray binary (HMXB) candidate, 34 stars and
185 active galactic nuclei (AGNs). In addition, we have classified 32 sources
as 'hard' AGNs which are likely absorbed by local gas and dust, and nine 'soft'
AGNs whose nature is still unclear. Considering the abundance of HMXBs
discovered so far in the Bar of the SMC the number that we have detected in the
Wing is low.


title:
Global classification of two-component approximately integrable
  evolution equations

abstract:
  We globally classify two-component evolution equations, with homogeneous
diagonal linear part, admitting infinitely many approximate symmetries.
Important ingredients are the symbolic calculus of Gel'fand and Dikii, the
Skolem-Mahler-Lech theorem, results on diophantine equations in roots of unity
by F. Beukers, and an algorithm of C.J. Smyth.


title:
Associated production of a Kaluza-Klein excitation of a gluon with a t
  t(bar) pair at the LHC

abstract:
  In Randall-Sundrum models, the Kaluza-Klein (KK) excitations of the gluon,
g_{KK} have enhanced couplings to the right-handed quarks. In the absence of a
gg g_{KK} coupling in these models, the single production of a g_{KK} from an
initial gg state is not possible. The search for other production mechanisms at
the LHC, therefore, becomes important. We suggest that the associated
production of a g_{KK} with a t t(bar) pair is such a mechanism. Our study
shows that through this process the LHC can probe KK gluon masses in the range
of 2.8 -- 2.9 TeV.


title: Proteins in a shear flow

abstract:
  The conformational dynamics of a single protein molecule in a shear flow is
investigated using Brownian dynamics simulations. A structure-based coarse
grained model of a protein is used. We consider two proteins, ubiquitin and
integrin, and find that at moderate shear rates they unfold through a sequence
of metastable states - a pattern which is distinct from a smooth unraveling
found in homopolymers. Full unfolding occurs only at very large shear rates.
Furthermore, the hydrodynamic interactions between the amino acids are shown to
hinder the shear flow unfolding. The characteristics of the unfolding process
depend on whether a protein is anchored or not, and if it is, on the choice of
an anchoring point.


title: Running of $\alpha_s$ in the MSSM with three-loop accuracy

abstract:
  The evolution of the strong coupling constant $\alpha_s$ from $M_Z$ to the
GUT scale is presented, involving three-loop running and two-loop decoupling.
Accordingly, the two-loop transition from the $\bar{\rm MS}$ to the $\bar{\rm
DR}$ scheme is properly taken into account. We find that the three-loop effects
are comparable to the experimental uncertainty for $\alpha_s$.


title:
Formation, fractionation and excitation of carbon monoxide in diffuse
  clouds

abstract:
  Aims: Our aims are threefold: a) To compare the $uv$ and mm-wave results; b)
to interpret 13CO and 12CO abundances in terms of the physical processes which
separately and jointly determine them; c) to interpret observed J=1-0
rotational excitation and line brightness in terms of ambient gas properties.
  Methods: A simple phenomenological model of CO formation as the immediate
descendant of quiescently-recombining HCO+ is used to study the accumulation,
fractionation and rotational excitation of CO in more explicit and detailed
models of H2-bearing diffuse/H I clouds
  Results: The variation of N(CO) with N(H2) is explained by quiescent
recombination of a steady fraction n(HCO+)/n(H2) = 2 x 10^{-9}. Observed
N(12CO))/N(13CO) ratios generally do not require a special chemistry but result
from competing processes and do not provide much insight into the local gas
properties, especially the temperature. J=1-0 CO line brightnesses directly
represent N(CO), not N(H2), so the CO-H2 conversion factor varies widely; it
attains typical values at N(12CO) \la 10^{16}cm^{-2}. Models of CO rotational
excitation account for the line brightnesses and CO-H2 conversion factors but
readily reproduce the observed excitation temperatures and optical depths of
the rotational transitions only if excitation by H-atoms is weak -- as seems to
be the case for the very most recent calculations of these excitation rates.


title: Disentanglement in qubit-qutrit systems

abstract:
  We examine the phenomenon of {\it entanglement sudden death} (ESD) for $(2
\times 3)$-dimensional systems. As for $2 \times 2$ systems, the negativity
vanishes in finite time for some entangled pure as well as mixed states. While
locally equivalent pure states do so asymptotically. Interference between the
decay of the two upper levels to the lowest one in the qutrit adds further
richness to ESD in this systems.


title: Magnetic fields in noncommutative quantum mechanics

abstract:
  We discuss various descriptions of a quantum particle on noncommutative space
in a (possibly non-constant) magnetic field. We have tried to present the basic
facts in a unified and synthetic manner, and to clarify the relationship
between various approaches and results that are scattered in the literature.


title: The radiative lifetime of metastable CO ($a^3\Pi, v=0$)

abstract:
  We present a combined experimental and theoretical study on the radiative
lifetime of CO in the $a^3\Pi_{1,2}, v=0$ state. CO molecules in a beam are
prepared in selected rotational levels of this metastable state,
Stark-decelerated and electrostatically trapped. From the phosphorescence decay
in the trap, the radiative lifetime is measured to be $2.63\pm0.03$ ms for the
$a^3\Pi_1, v=0, J=1$ level. From spin-orbit coupling between the $a^3\Pi$ and
the $A^1\Pi$ state a 20% longer radiative lifetime of 3.16 ms is calculated for
this level. It is concluded that coupling to other $^1\Pi$ states contributes
to the observed phosphorescence rate of metastable CO.


title: A Catalog of Galaxy Clusters Observed by XMM-Newton

abstract:
  Aims: We present a uniform catalog of the images and radial profiles of the
temperature, abundance, and brightness for 70 clusters of galaxies observed by
XMM-Newton.
  Methods: We use a new "first principles" approach to the modeling and removal
of the background components; the quiescent particle background, the cosmic
diffuse emission, the soft proton contamination, and the solar wind charge
exchange emission. Each of the background components demonstrate significant
spectral variability, several have spatial distributions that are not described
by the photon vignetting function, and all except for the cosmic diffuse
emission are temporally variable. Because these backgrounds strongly affect the
analysis of low surface brightness objects, we provide a detailed description
our methods of identification, characterization, and removal.
  Results: We have applied these methods to a large collection of XMM-Newton
observations of clusters of galaxies and present the resulting catalog. We find
significant systematic differences between the Chandra and XMM-Newton
temperatures.


title:
Non-vanishing theorems for rank 2 bundles on P^3: a simple approach
  without the speciality lemma

abstract:
  The paper investigates vanishing conditions on the first cohomology module of
a normalized rank 2 vector bundle E on P^3 which force E to split, and finds
therefore strategic levels of non-vanishing for a non-split bundle. The present
conditions improve other conditions known in the literature and are obtained
with simple computations on the Euler characteristic function, avoiding the
speciality lemma, Barth's restriction theorem, the discriminat property, and
other heavy tools.


title: Edge Local Complementation and Equivalence of Binary Linear Codes

abstract:
  Orbits of graphs under the operation edge local complementation (ELC) are
defined. We show that the ELC orbit of a bipartite graph corresponds to the
equivalence class of a binary linear code. The information sets and the minimum
distance of a code can be derived from the corresponding ELC orbit. By
extending earlier results on local complementation (LC) orbits, we classify the
ELC orbits of all graphs on up to 12 vertices. We also give a new method for
classifying binary linear codes, with running time comparable to the best known
algorithm.


title: Compact oscillons in the signum-Gordon model

abstract:
  We present explicit solutions of the signum-Gordon scalar field equation
which have finite energy and are periodic in time. Such oscillons have a
strictly finite size. They do not emit radiation.


title: Size, power and false discovery rates

abstract:
  Modern scientific technology has provided a new class of large-scale
simultaneous inference problems, with thousands of hypothesis tests to consider
at the same time. Microarrays epitomize this type of technology, but similar
situations arise in proteomics, spectroscopy, imaging, and social science
surveys. This paper uses false discovery rate methods to carry out both size
and power calculations on large-scale problems. A simple empirical Bayes
approach allows the false discovery rate (fdr) analysis to proceed with a
minimum of frequentist or Bayesian modeling assumptions. Closed-form accuracy
formulas are derived for estimated false discovery rates, and used to compare
different methodologies: local or tail-area fdr's, theoretical, permutation, or
empirical null hypothesis estimates. Two microarray data sets as well as
simulations are used to evaluate the methodology, the power diagnostics showing
why nonnull cases might easily fail to appear on a list of ``significant''
discoveries.


title:
Probing the Slope of Cluster Mass Profile with Gravitational Einstein
  Rings: Application to Abell 1689

abstract:
  The strong lensing modelling of gravitational ``rings'' formed around massive
galaxies is sensitive to the amplitude of the external shear and convergence
produced by nearby mass condensations. In current wide field surveys, it is now
possible to find out a large number of rings, typically 10 gravitational rings
per square degree. We propose here, to systematically study gravitational rings
around galaxy clusters to probe the cluster mass profile beyond the cluster
strong lensing regions. For cluster of galaxies with multiple arc systems, we
show that rings found at various distances from the cluster centre can improve
the modelling by constraining the slope of the cluster mass profile. We outline
the principle of the method with simple numerical simulations and we apply it
to 3 rings discovered recently in Abell~1689. In particular, the lens modelling
of the 3 rings confirms that the cluster is bimodal, and favours a slope of the
mass profile steeper than isothermal at a cluster radius $\sim 300 \kpc$. These
results are compared with previous lens modelling of Abell~1689 including weak
lensing analysis. Because of the difficulty arising from the complex mass
distribution in Abell~1689, we argue that the ring method will be better
implemented on simpler and relaxed clusters.


title:
New Companions for the lonely Crab? VHE emission from young pulsar wind
  nebulae revealed by H.E.S.S

abstract:
  The deeper and more extended survey of the central parts of the Galactic
Plane by H.E.S.S. during 2005-2007 has revealed a number of new point-like, as
well as, extended sources. Two point-like sources can be associated to two
remarkable objects around "Crab-like" young and energetic pulsars in our
Galaxy: G21.5-0.9 and Kes 75. The characteristics of each of the sources are
presented and possible interpretations are briefly discussed.


title: RXTE confirmation of the Intermediate Polar status of Swift J0732.5-1331

abstract:
  Aims. We intend to establish the X-ray properties of Swift J0732.5-1331 and
therefore confirm its status as an intermediate polar. Method. We analysed
36,240 s of X-ray data from RXTE. Frequency analysis was used to constrain
temporal variations and spectral analysis used to characterise the emission and
absorption properties. Results. The X-ray spin period is confirmed to be
512.4(3) s with a strong first harmonic. No modulation is detected at the
candidate orbital period of 5.6 h, but a coherent modulation is present at the
candidate 11.3 h period. The spectrum is consistent with a 37 keV
bremsstrahlung continuum with an iron line at 6.4 keV absorbed by an equivalent
hydrogen column density of around 10^22 atoms cm^-2. Conclusions. Swift
J0732-1331 is confirmed to be an intermediate polar.


title: Total cross section of pp -> pK+Lambda reaction near threshold

abstract:
  The total cross sections of the pp -> pK+ Lambda reaction near threshold
measured at the COSY(Juelich) synchrotron using the internal target facility
COSY-11 are described in the frame of the model taking into account the one
pion and one kaon exchange as well as the final state interaction mechanisms.


title:
Efficient Simulations of Interstellar Gas-Grain Chemistry Using Moment
  Equations

abstract:
  Networks of reactions on dust grain surfaces play a crucial role in the
chemistry of interstellar clouds, leading to the formation of molecular
hydrogen in diffuse clouds as well as various organic molecules in dense
molecular clouds. Due to the sub-micron size of the grains and the low flux,
the population of reactive species per grain may be very small and strongly
fluctuating. Under these conditions rate equations fail and the simulation of
surface-reaction networks requires stochastic methods such as the master
equation. However, the master equation becomes infeasible for complex networks
because the number of equations proliferates exponentially. Here we introduce a
method based on moment equations for the simulation of reaction networks on
small grains. The number of equations is reduced to just one equation per
reactive specie and one equation per reaction. Nevertheless, the method
provides accurate results, which are in excellent agreement with the master
equation. The method is demonstrated for the methanol network which has been
recently shown to be of crucial importance.


title:
Phenomenological applications of non-perturbative heavy quark effective
  theory

abstract:
  We briefly review the strategy to perform non-perturbative heavy quark
effective theory computations and we specialize to the case of the b quark mass
which has recently been computed including the 1/m term.


title: The Spectrum of 1ES0229 + 200 and the Cosmic Infrared Background

abstract:
  We examine the effect of gamma-ray absorption by the extragalactic infrared
radiation on intrinsic spectra predicted for 1ES0229+200 and compare our
results with the observational data. We find agreement with our previous
results on the shape of the IR spectral energy distribution (SED), contrary to
the recent assertion of the HESS group. Our analysis indicates that 1ES0229+200
has a very hard intrinsic spectrum with a spectral index between 1.1 +/- 0.3
and 1.5 +/- 0.3 in the energy range between ~0.5 TeV and ~15 TeV. Under the
assumptions that (1) the SED models of Stecker, Malkan & Scully (2006) are
reasonable as derived from numerous detailed IR observations, and (2) spectral
indexes in the range 1 < \Gamma < 1.5 have been shown to be obtainable from
relativistic shock acceleration under the astrophysical conditions extant in
blazar flares (Stecker, Baring & Summerlin 2007), the fits to the observations
of 1ES0229+200 using our previous IR SEDs are consistent with both the IR and
gamma-ray observations. Our analysis presents evidence indicating that the
energy spectrum of relativistic particles in 1ES0229+200 is produced by
relativistic shock acceleration, producing an intrinsic gamma-ray spectrum with
index 1 < \Gamma < 1.5 and with no evidence of a peak in the SED up to energies
~15 TeV.


title: McKay's correspondence for cocompact discrete subgroups of SU(1,1)

abstract:
  The classical McKay correspondence establishes an explicit link from the
representation theory of a finite subgroup G of SU(2) and the geometry of the
minimal resolution of the quotient of the affine plane by G. In this paper we
discuss a possible generalization of the McKay correspondence to the case when
G is replaced with a cocompact discrete subgroup of the universal cover of
SU(1,1) such that its image in PSU(1,1) is a cocompact fuchsian group with
quotient of genus 0. We establish a correspondence between a certain class of
finite-dimensional unitary representations of G and vector bundles on an open
algebraic surface with the trivial canonical class canonically associated to G.


title: Adding inverses to diagrams II: Invertible homotopy theories are spaces

abstract:
  In previous work, we showed that there are appropriate model category
structures on the category of simplicial categories and on the category of
Segal precategories, and that they are Quillen equivalent to one another and to
Rezk's complete Segal space model structure on the category of simplicial
spaces. Here, we show that these results still hold if we instead use groupoid
or "invertible" cases. Namely, we show that model structures on the categories
of simplicial groupoids, Segal pregroupoids, and invertible simplicial spaces
are all Quillen equivalent to one another and to the standard model structure
on the category of spaces. We prove this result using two different approaches
to invertible complete Segal spaces and Segal groupoids.


title: A phase-space study of jet formation in planetary-scale fluids

abstract:
  The interaction between planetary waves and an arbitrary zonal flow is
studied from a phase-space viewpoint. Using the Wigner distribution, a
planetary wave Vlasov equation is derived that includes the contribution of the
mean flow to the zonal potential vorticity gradient. This equation is applied
to the problem of planetary wave modulational instability, where it is used to
predict a fastest growing mode of finite wavenumber. A wave-mean flow numerical
model is used to test the analytical predictions, and an intuitive explanation
of modulational instability and jet asymmetry is given via the motion of
planetary wavepackets in phase space.


title:
Integral transformation solution of free-space cylindrical vector beams
  and prediction of modified-Bessel-Gaussian vector beams

abstract:
  A unified description of the free-space cylindrical vector beams is
presented, which is an integral transformation solution to the vector Helmholtz
equation and the transversality condition. The amplitude 2-form of the angular
spectrum involved in this solution can be arbitrarily chosen. When one of the
two elements is zero, we arrive at either transverse-electric or
transverse-magnetic beam mode. In the paraxial condition, this solution not
only includes the known $J_1$ Bessel-Gaussian vector beam and the axisymmetric
Laguerre-Gaussian vector beam that were obtained by solving the paraxial wave
equations, but also predicts two new kinds of vector beam, called the
modified-Bessel-Gaussian vector beam.


title: Finite Unified Theories confronted with low-energy phenomenology

abstract:
  Finite Unified Theories (FUTs) are N=1 supersymmetric Grand Unified Theories
that can be made all-loop finite. The requirement of all-loop finiteness leads
to a severe reduction of the free parameters of the theory and, in turn, to a
large number of predictions. Here SU(5) FUTs are investigated in the context of
low-energy phenomenology observables. We present a detailed scanning of these
FUTs, including theoretical uncertainties at the unification scale and applying
all phenomenological constraints. Taking into account the restrictions from the
top and bottom quark masses, we can discriminate between different models.
Including further low-energy constraints such as $B$ physics observables, the
bound on the lightest Higgs boson mass and the cold dark matter density, we
determine the predictions of the allowed parameter space for the Higgs boson
sector and the supersymmetric particle spectrum of the model.


title: Control of generalized error rates in multiple testing

abstract:
  Consider the problem of testing $s$ hypotheses simultaneously. The usual
approach restricts attention to procedures that control the probability of even
one false rejection, the familywise error rate (FWER). If $s$ is large, one
might be willing to tolerate more than one false rejection, thereby increasing
the ability of the procedure to correctly reject false null hypotheses. One
possibility is to replace control of the FWER by control of the probability of
$k$ or more false rejections, which is called the $k$-FWER. We derive both
single-step and step-down procedures that control the $k$-FWER in finite
samples or asymptotically, depending on the situation. We also consider the
false discovery proportion (FDP) defined as the number of false rejections
divided by the total number of rejections (and defined to be 0 if there are no
rejections). The false discovery rate proposed by Benjamini and Hochberg [J.
Roy. Statist. Soc. Ser. B 57 (1995) 289--300] controls $E(FDP)$. Here, the goal
is to construct methods which satisfy, for a given $\gamma$ and $\alpha$,
$P\{FDP>\gamma\}\le \alpha$, at least asymptotically. In contrast to the
proposals of Lehmann and Romano [Ann. Statist. 33 (2005) 1138--1154], we
construct methods that implicitly take into account the dependence structure of
the individual test statistics in order to further increase the ability to
detect false null hypotheses. This feature is also shared by related work of
van der Laan, Dudoit and Pollard [Stat. Appl. Genet. Mol. Biol. 3 (2004)
article 15], but our methodology is quite different. Like the work of Pollard
and van der Laan [Proc. 2003 International Multi-Conference in Computer Science
and Engineering, METMBS'03 Conference (2003) 3--9] and Dudoit, van der Laan and
Pollard [Stat. Appl. Genet. Mol. Biol. 3 (2004) article 13], we employ
resampling methods to achieve our goals. Some simulations compare finite sample
performance to currently available methods.


title: Sub-THz electrodynamics of the graphene-like superconductor CaAlSi

abstract:
  We report the first optical study of CaAlSi, a superconductor which displays
both the crystal structure of MgB2 and the electronic band structure of
intercalated graphites. The reflectivity of a CaAlSi single crystal was
measured down to sub-THz frequencies and to 3.3 K, with the use of Coherent
Synchrotron Radiation. A superconducting gap in the hexagonal planes, two gaps
along the c axis were found and measured, as expected from the structure of the
CaAlSi Fermi surface. The anisotropic optical parameters of the normal state
were also determined.


title:
Nonisospectral integrable nonlinear equations with external potentials
  and their GBDT solutions

abstract:
  Auxiliary systems for matrix nonisospectral equations, including coupled NLS
with external potential and KdV with variable coefficients, were introduced.
Explicit solutions of nonisospectral equations were constructed using the GBDT
version of the B\"acklund-Darboux transformation.


title: Comparison of work fluctuation relations

abstract:
  We compare two predictions regarding the microscopic fluctuations of a system
that is driven away from equilibrium: one due to Crooks [J. Stat. Phys. 90,
1481 (1998)] which has gained recent attention in the context of nonequilibrium
work and fluctuation theorems, and an earlier, analogous result obtained by
Bochkov and Kuzovlev [Zh. Eksp. Teor. Fiz. 72(1), 238247 (1977)]. Both results
quantify irreversible behavior by comparing probabilities of observing
particular microscopic trajectories during thermodynamic processes related by
time-reversal, and both are expressed in terms of the work performed when
driving the system away from equilibrium. By deriving these two predictions
within a single, Hamiltonian framework, we clarify the precise relationship
between them, and discuss how the different definitions of work used by the two
sets of authors gives rise to different physical interpretations. We then
obtain a extended fluctuation relation that contains both the Crooks and the
Bochkov-Kuzovlev results as special cases.


title: A Method for Weak Lensing Flexion Analysis by the HOLICs Moment Approach

abstract:
  We have developed a method for measuring higher-order weak lensing
distortions of faint background galaxies, namely the weak gravitational
flexion, by fully extending the Kaiser, Squires & Broadhurst method to include
higher-order lensing image characteristics (HOLICs) introduced by Okura,
Umetsu, & Futamase. We take into account explicitly the weight function in
calculations of noisy shape moments and the effect of higher-order PSF
anisotropy, as well as isotropic PSF smearing. Our HOLICs formalism allows
accurate measurements of flexion from practical observational data in the
presence of non-circular, anisotropic PSF. We test our method using mock
observations of simulated galaxy images and actual, ground-based
  Subaru observations of the massive galaxy cluster A1689 ($z=0.183$). From the
high-precision measurements of spin-1 first flexion, we obtain a
high-resolution mass map in the central region of A1689. The reconstructed mass
map shows a bimodal feature in the central $4'\times 4'$ region of the cluster.
The major, pronounced peak is associated with the brightest cluster galaxy and
central cluster members, while the secondary mass peak is associated with a
local concentration of bright galaxies. The refined, high-resolution mass map
of A1689 demonstrates the power of the generalized weak lensing analysis
techniques for quantitative and accurate measurements of the weak gravitational
lensing signal.


title:
Efficient Stochastic Simulations of Complex Reaction Networks on
  Surfaces

abstract:
  Surfaces serve as highly efficient catalysts for a vast variety of chemical
reactions. Typically, such surface reactions involve billions of molecules
which diffuse and react over macroscopic areas. Therefore, stochastic
fluctuations are negligible and the reaction rates can be evaluated using rate
equations, which are based on the mean-field approximation. However, in case
that the surface is partitioned into a large number of disconnected microscopic
domains, the number of reactants in each domain becomes small and it strongly
fluctuates. This is, in fact, the situation in the interstellar medium, where
some crucial reactions take place on the surfaces of microscopic dust grains.
In this case rate equations fail and the simulation of surface reactions
requires stochastic methods such as the master equation. However, in the case
of complex reaction networks, the master equation becomes infeasible because
the number of equations proliferates exponentially. To solve this problem, we
introduce a stochastic method based on moment equations. In this method the
number of equations is dramatically reduced to just one equation for each
reactive species and one equation for each reaction. Moreover, the equations
can be easily constructed using a diagrammatic approach. We demonstrate the
method for a set of astrophysically relevant networks of increasing complexity.
It is expected to be applicable in many other contexts in which problems that
exhibit analogous structure appear, such as surface catalysis in nanoscale
systems, aerosol chemistry in stratospheric clouds and genetic networks in
cells.


title:
Evaluation of the Multiplane Method for Efficient Simulations of
  Reaction Networks

abstract:
  Reaction networks in the bulk and on surfaces are widespread in physical,
chemical and biological systems. In macroscopic systems, which include large
populations of reactive species, stochastic fluctuations are negligible and the
reaction rates can be evaluated using rate equations. However, many physical
systems are partitioned into microscopic domains, where the number of molecules
in each domain is small and fluctuations are strong. Under these conditions,
the simulation of reaction networks requires stochastic methods such as direct
integration of the master equation. However, direct integration of the master
equation is infeasible for complex networks, because the number of equations
proliferates as the number of reactive species increases. Recently, the
multiplane method, which provides a dramatic reduction in the number of
equations, was introduced [A. Lipshtat and O. Biham, Phys. Rev. Lett. 93,
170601 (2004)]. The reduction is achieved by breaking the network into a set of
maximal fully connected sub-networks (maximal cliques). Lower-dimensional
master equations are constructed for the marginal probability distributions
associated with the cliques, with suitable couplings between them. In this
paper we test the multiplane method and examine its applicability. We show that
the method is accurate in the limit of small domains, where fluctuations are
strong. It thus provides an efficient framework for the stochastic simulation
of complex reaction networks with strong fluctuations, for which rate equations
fail and direct integration of the master equation is infeasible. The method
also applies in the case of large domains, where it converges to the rate
equation results.


title:
Controlling spatiotemporal chaos and spiral turbulence in excitable
  media: A review

abstract:
  Excitable media are a generic class of models used to simulate a wide variety
of natural systems including cardiac tissue. Propagation of excitation waves in
this medium results in the formation of characteristic patterns such as
rotating spiral waves. Instabilities in these structures may lead to
spatiotemporal chaos through spiral turbulence, which has been linked to
clinically diagnosed conditions such as cardiac fibrillation. Usual methods for
controlling such phenomena involve very large amplitude perturbations and have
several drawbacks. There have been several recent attempts to develop
low-amplitude control procedures for spatiotemporal chaos in excitable media
which are reviewed in this paper. The control schemes have been broadly
classified by us into three types: (i) global, (ii) non-global
spatially-extended and (iii) local, depending on the way the control signal is
applied, and we discuss the merits and drawbacks for each.


title: Bihermitian metrics on Hopf surfaces

abstract:
  Inspired by a construction due to Hitchin, we produce strongly bihermitian
metrics on certain Hopf complex surfaces, which integrate the locally
conformally Kaehler metrics found by Gauduchon and Ornea. We also show that the
Inoue complex surfaces with zero second Betti number do not admit bihermitian
metrics. This completes the classification of the compact complex surfaces
admitting strongly bihermitian metrics.


title: A Note on the Effective Non-vanishing Conjecture

abstract:
  We give a reduction of the irregular case for the effective non-vanishing
conjecture by virtue of the Fourier-Mukai transform. As a consequence, we
reprove that the effective non-vanishing conjecture holds on algebraic
surfaces.


title: Complexity of some Path Problems in DAGs and Linear Orders

abstract:
  We investigate here the computational complexity of three natural problems in
directed acyclic graphs. We prove their NP Completeness and consider their
restrictions to linear orders.


title: On the Farrell-Jones and related Conjectures

abstract:
  These extended notes are based on a series of six lectures presented at the
summer school ``Cohomology of groups and algebraic $K$-theory'' which took
place in Hangzhou, China from July 1 until July 12 in 2007. They give an
introduction to the Farrell-Jones and the Baum-Connes Conjecture.


title: On the low-energy density of states in disordered d-wave superconductor

abstract:
  We study the low-energy density of states of Dirac fermions in disordered
d-wave superconductor. At zero energy, a finite density of states is obtained
via the mechanism of dynamical mass generation in an effective
(1+1)-dimensional relativistic field theory.


title:
Support of generalized parton distributions in Bethe-Salpeter models of
  hadrons

abstract:
  The proper support of generalized parton distributions from relativistic
constituent quark models with pointlike constituents is studied. The correct
support is guaranteed when the vertex function does not depend on the relative
minus-momentum. We show that including quark interactions in models with
pointlike constituent quarks might lead to a support problem. A computation of
the magnitude of the support problem in the Bonn relativistic constituent quark
model is presented.


title:
Single-Particle Dynamics in the Vicinity of the Mott-Hubbard
  Metal-to-Insulator Transition

abstract:
  The single-particle dynamics close to a metal-to-insulator transition induced
by strong repulsive interaction between the electrons is investigated. The
system is described by a half-filled Hubbard model which is treated by dynamic
mean-field theory evaluated by high-resolution dynamic density-matrix
renormalization. We provide theoretical spectra with momentum resolution which
facilitate the comparison to photoelectron spectroscopy.


title: Constituent and current quark masses at low chiral energies

abstract:
  Light constituent quark masses and the corresponding dynamical quark masses
are determined by data, the Quark-Level Linear $\sigma$ Model, and infrared
QCD. This allows to define effective nonstrange and strange current quark
masses which reproduce the experimental pion and kaon masses very accurately,
by simple additivity. Moreover, the masses of the light scalar mesons
$\sigma(600)$ and $\kappa(800)$ can be obtained straightforwardly from the
constituent quark masses. In contrast, the usual nonstrange and strange current
quark masses employed by Chiral Perturbation Theory do not allow a simple
quantitative explanation of the pion and kaon masses.


title:
Phase diagram of the one-dimensional Hubbard model with
  next-nearest-neighbor hopping

abstract:
  We study the one-dimensional Hubbard model with nearest-neighbor and
next-nearest-neighbor hopping integrals by using the density-matrix
renormalization group (DMRG) method and Hartree-Fock approximation. Based on
the calculated results for the spin gap, total-spin quantum number, and
Tomonaga-Luttinger-liquid parameter, we determine the ground-state phase
diagram of the model in the entire filling and wide parameter region. We show
that, in contrast to the weak-coupling regime where a spin-gapped liquid phase
is predicted in the region with four Fermi points, the spin gap vanishes in a
substantial region in the strong-coupling regime. It is remarkable that a large
variety of phases, such as the paramagnetic metallic phase, spin-gapped liquid
phase, singlet and triplet superconducting phases, and fully polarized
ferromagnetic phase, appear in such a simple model in the strong-coupling
regime.


title: Pion structure in QCD: From theory to lattice to experimental data

abstract:
  We describe the present status of the pion distribution amplitude (DA) as it
originates from several sources: (i) a nonperturbative approach based on QCD
sum rules with nonlocal condensates, (ii) an $O(\alpha_s)$ QCD analysis of the
CLEO data on F^{\gamma\gamma^*\pi}(Q^2) with asymptotic and renormalon models
for higher twists, and (iii) recent high-precision lattice QCD calculations of
the second moment of the pion DA. We show predictions for the pion
electromagnetic form factor, obtained in analytic QCD perturbation theory, and
compare it with the JLab data on F_{\pi}(Q^2). We also discuss in this context
an improved model for nonlocal condensates in QCD and show its consequences for
the pion DA and the \gamma\gamma^*\to\pi transition form factor. We include a
brief analysis of meson-induced massive lepton (muon) Drell--Yan production for
the process \pi^{-}N\to\mu^{+}\mu^{-}X, considering both an unpolarized nucleon
target and longitudinally polarized protons.


title: Optical coupling of fundamental whispering gallery modes in bi-spheres

abstract:
  What will happen if two identical microspheres, with fundamental whispering
gallery modes excited in each of them, become optically coupled? Conventional
wisdom based on coupled-mode arguments says that two new modes, bonding and
anti-bonding, with two split frequencies would be formed. In this paper we
demonstrate, using exact multi-sphere Mie theory, that in reality an attempt to
couple two fundamental modes of microspheres would result in a complex
multi-resonance optical response with the field distribution significantly
deviating from predictions of coupled-mode type theories.


title:
Renormalization of Polyakov loops in fundamental and higher
  representations

abstract:
  We compare two renormalization procedures, one based on the short distance
behavior of heavy quark-antiquark free energies and the other by using bare
Polyakov loops at different temporal extent of the lattice and find that both
prescriptions are equivalent, resulting in renormalization constants that
depend on the bare coupling. Furthermore these renormalization constants show
Casimir scaling for higher representations of the Polyakov loops. The analysis
of Polyakov loops in different representations of the color SU(3) group
indicates that a simple perturbative inspired relation in terms of the
quadratic Casimir operator is realized to a good approximation at temperatures
$T \gsim T_c$ for renormalized as well as bare loops. In contrast to a
vanishing Polyakov loop in representations with non-zero triality in the
confined phase, the adjoint loops are small but non-zero even for temperatures
below the critical one. The adjoint quark-antiquark pairs exhibit screening.
This behavior can be related to the binding energy of gluelump states.


title: Exploiting B Site Disorder for Phase Control in the Manganites

abstract:
  Disorder on the active d element site is usually very disruptive for
conduction and long range order in perovskite transition metal oxides. However,
in the background of phase competition such `B site' dopants also act to
promote one ordered phase at the expense of another. This occurs either through
valence change of the transition metal or via creation of `defects' in the
parent magnetic state. We provide a framework for understanding the complex
variety of phenomena observed in B site doped manganites and identify the key
parameters that control the physics. Using a spatially resolved analysis of B
ions in various manganite phases we explain the existing data and predict new
situations where highly polarisable phase separated states can be created.


title: Unit Rectangle Visibility Graphs

abstract:
  Over the past twenty years, rectangle visibility graphs have generated
considerable interest, in part due to their applicability to VLSI chip design.
Here we study unit rectangle visibility graphs, with fixed dimension
restrictions more closely modeling the constrained dimensions of gates and
other circuit components in computer chip applications. A graph $G$ is a unit
rectangle visibility graph (URVG) if its vertices can be represented by closed
unit squares in the plane with sides parallel to the axes and pairwise disjoint
interiors, in such a way that two vertices are adjacent if and only if there is
a non-degenerate horizontal or vertical band of visibility joining the two
rectangles. Our results include necessary and sufficient conditions for $K_n$,
$K_{m,n}$, and trees to be URVGs, as well as a number of general edge bounds.


title:
Hydrodynamical modeling of the deconfinement phase transition and
  explosive hadronization

abstract:
  Dynamics of relativistic heavy-ion collisions is investigated on the basis of
a simple (1+1)-dimensional hydrodynamical model in light-cone coordinates. The
main emphasis is put on studying sensitivity of the dynamics and observables to
the equation of state and initial conditions. Low sensitivity of pion rapidity
spectra to the presence of the phase transition is demonstrated, and some
inconsistencies of the equilibrium scenario are pointed out. Possible
non-equilibrium effects are discussed, in particular, a possibility of an
explosive disintegration of the deconfined phase into quark-gluon droplets.
Simple estimates show that the characteristic droplet size should decrease with
increasing the collective expansion rate. These droplets will hadronize
individually by emitting hadrons from the surface. This scenario should reveal
itself by strong non-statistical fluctuations of observables.


title: Non-linear Lie conformal algebras with three generators

abstract:
  We classify certain non-linear Lie conformal algebras with three generators,
which can be viewed as deformations of the current Lie conformal algebra of
sl_2. In doing so we discover an interesting 1-parameter family of non-linear
Lie conformal algebras R_{-1}^d and the corresponding freely generated vertex
algebras V_{-1}^d, which includes for d=1 the affine vertex algebra of sl_2 at
the critical level k=-2. We construct free-field realizations of the algebras
V_{-1}^d extending the Wakimoto realization of the affine vertex algebra of
sl_2 at the critical level, and we compute their Zhu algebras.


title:
On crossed product rings with twisted involutions, their module
  categories and L-theory

abstract:
  We study the Farrell-Jones Conjecture with coefficients in an additive
G-category with involution. This is a variant of the L-theoretic Farrell-Jones
Conjecture which originally deals with group rings with the standard
involution. We show that this formulation of the conjecture can be applied to
crossed product rings R*G equipped with twisted involutions and automatically
implies the a priori more general fibered version.


title:
Phenomenological study of the electronic transport coefficients of
  graphene

abstract:
  Using a semi-classical approach and input from experiments on the
conductivity of graphene, we determine the electronic density dependence of the
electronic transport coefficients -- conductivity, thermal conductivity and
thermopower -- of doped graphene. Also the electronic density dependence of the
optical conductivity is obtained. Finally we show that the classical Hall
effect (low field) in graphene has the same form as for the independent
electron case, characterized by a parabolic dispersion, as long as the
relaxation time is proportional to the momentum.


title: Symmetric and Synchronous Communication in Peer-to-Peer Networks

abstract:
  Motivated by distributed implementations of game-theoretical algorithms, we
study symmetric process systems and the problem of attaining common knowledge
between processes. We formalize our setting by defining a notion of
peer-to-peer networks(*) and appropriate symmetry concepts in the context of
Communicating Sequential Processes (CSP), due to the common knowledge creating
effects of its synchronous communication primitives. We then prove that CSP
with input and output guards makes common knowledge in symmetric peer-to-peer
networks possible, but not the restricted version which disallows output
statements in guards and is commonly implemented.
  (*) Please note that we are not dealing with fashionable incarnations such as
file-sharing networks, but merely use this name for a mathematical notion of a
network consisting of directly connected peers "treated on an equal footing",
i.e. not having a client-server structure or otherwise pre-determined roles.)


title: Comment on "Modified Coulomb Law in a Strongly Magnetized Vacuum"

abstract: This is a comment on Phys. Rev. Lett. 98, 180403 (2007) [arXiv:0704.2162].


title: BCS theory for finite size superconductors

abstract:
  We study finite size effects in superconducting metallic grains and determine
the BCS order parameter and the low energy excitation spectrum in terms of
size, and shape of the grain. Our approach combines the BCS self-consistency
condition, a semiclassical expansion for the spectral density and interaction
matrix elements, and corrections to the BCS mean-field. In chaotic grains
mesoscopic fluctuations of the matrix elements lead to a smooth dependence of
the order parameter on the excitation energy. In the integrable case we observe
shell effects when e.g. a small change in the electron number leads to large
changes in the energy gap.


title: Gravitino Dark Matter with Broken R-parity

abstract:
  Scenarios with gravitino dark matter face potential cosmological problems
induced by the presence of the Next-to-Lightest Supersymmetric Particle (NLSP)
at the time of Big Bang Nucleosynthesis (BBN). A very simple, albeit radical,
solution to avoid all these problems consists on assuming that R-parity is
slightly violated, since in this case the NLSP decays well before the onset of
BBN. Remarkably, even if the gravitino is no longer stable in this scenario, it
still constitutes a very promising dark matter candidate. In this talk we
review the motivations for this scenario and we present a model that naturally
generates R-parity breaking parameters of the right size to produce a
consistent thermal history of the Universe, while satisfying at the same time
all the laboratory and cosmological bounds on R-parity breaking. We also
discuss possible signatures of this scenario at gamma ray observatories and at
colliders.


title: VERITAS Data Acquisition

abstract:
  VERITAS employs a multi-stage data acquisition chain that extends from the
VME readout of custom 500 MS/s flash ADC electronics to the construction of
telescope events and ultimately the compilation of information from each
telescope into array level data. These systems provide access to the
programming of the channel level triggers and the FADCs. They also ensure the
proper synchronization of event information across the array and provide the
first level of data quality monitoring. Additionally, the data acquisition
includes features to handle the readout of special trigger types and to monitor
channel scaler rates. In this paper we describe the software and hardware
components of the systems and the protocols used to communicate between the
VME, telescope, and array levels. We also discuss the performance of the data
acquisition for array operations.


title: Decoherence induced by Smith-Purcell radiation

abstract:
  The interaction between charged particles and the vacuum fluctuations of the
electromagnetic field induces decoherence, and therefore affects the contrast
of fringes in an interference experiment. In this article we show that if a
double slit experiment is performed near a conducting grating, the fringe
visibility is reduced. We find that the reduction of contrast is proportional
to the number of grooves in the conducting surface, and that for realistic
values of the parameters it could be large enough to be observed. The effect
can be understood in terms of the Smith-Purcell radiation produced by the
surface currents induced in the conductor.


title:
Estimates of multipolar coefficients to search for cosmic ray
  anisotropies with non-uniform or partial sky coverage

abstract:
  We study the possibility to extract the multipolar moments of an underlying
distribution from a set of cosmic rays observed with non-uniform or even
partial sky coverage. We show that if the degree is assumed to be upper bounded
by $L$, each multipolar moment can be recovered whatever the coverage, but with
a variance increasing exponentially with the bound $L$ if the coverage is zero
somewhere. Despite this limitation, we show the possibility to test predictions
of a model without any assumption on $L$ by building an estimate of the
covariance matrix seen through the exposure function.


title: Rotating Black Holes in Higher Dimensions

abstract:
  The properties of higher-dimensional black holes can differ significantly
from those of black holes in four dimensions, since neither the uniqueness
theorem, nor the staticity theorem or the topological censorship theorem
generalize to higher dimensions. We first discuss black holes of
Einstein-Maxwell theory and Einstein-Maxwell-Chern-Simons theory with spherical
horizon topology. Here new types of stationary black holes are encountered. We
then discuss nonuniform black strings and present evidence for a horizon
topology changing transition.


title:
Gap generation for Dirac fermions on Lobachevsky plane in a magnetic
  field

abstract:
  We study symmetry breaking and gap generation for fermions in the 2D space of
constant negative curvature (the Lobachevsky plane) in an external covariantly
constant magnetic field in a four-fermion model. It is shown that due to the
magnetic and negative curvature catalysis phenomena the critical coupling
constant is zero and there is a symmetry breaking condensate in the chiral
limit even in free theory. We analyze solutions of the gap equation in the
cases of zero, weak, and strong magnetic fields. As a byproduct we calculate
the density of states and the Hall conductivity for noninteracting fermions
that may be relevant for studies of graphene.


title:
Trends in multiparticle production and some "predictions" for pp and
  PbPb collisions at LHC

abstract:
  Based on trends seen at lower energies we "predict" the multiplicities and
pseudorapidity distributions of particle density and elliptic flow that will be
seen in PbPb and pp collisions at the LHC. We argue that, if these predictions
turn out to be correct, either these quantities are insensitive to the state of
matter created in high energy heavy ion collisions or the observed simplicity
and universality of the data must be telling us something profound about the
mechanism of particle production, which to this date is not well understood.


title: Strong coupling expansion of Baxter equation in N=4 SYM

abstract:
  The anomalous dimensions of single-trace local Wilson operators with
covariant derivatives in maximally supersymmetric gauge theory are believed to
be generated from a deformed noncompact sl(2) Baxter equation. We perform a
systematic expansion of this equation at strong coupling in the
single-logarithmic limit of large conformal spin to overcome the limitation of
the asymptotic nature of the equation. The analysis is reduced to
Riemann-Hilbert problems for corresponding resolvents of Bethe roots in each
order of the quasiclassical expansion. We explicitly construct the resolvents
in the lowest two orders in strong coupling and find all local conserved
charges of the underlying long-range spin chain.


title: Solar Neutrinos: Models, Observations, and New Opportunities

abstract:
  I discuss the development and resolution of the solar neutrino problem, as
well as opportunities now open to us to extend our knowledge of main-sequence
stellar evolution and neutrino astrophysics.


title: Vertex Percolation on Expander Graphs

abstract:
  We say that a graph $G=(V,E)$ on $n$ vertices is a $\beta$-expander for some
constant $\beta>0$ if every $U\subseteq V$ of cardinality $|U|\leq \frac{n}{2}$
satisfies $|N_G(U)|\geq \beta|U|$ where $N_G(U)$ denotes the neighborhood of
$U$. In this work we explore the process of deleting vertices of a
$\beta$-expander independently at random with probability $n^{-\alpha}$ for
some constant $\alpha>0$, and study the properties of the resulting graph. Our
main result states that as $n$ tends to infinity, the deletion process
performed on a $\beta$-expander graph of bounded degree will result with high
probability in a graph composed of a giant component containing $n-o(n)$
vertices that is in itself an expander graph, and constant size components. We
proceed by applying the main result to expander graphs with a positive spectral
gap. In the particular case of $(n,d,\lambda)$-graphs, that are such expanders,
we compute the values of $\alpha$, under additional constraints on the graph,
for which with high probability the resulting graph will stay connected, or
will be composed of a giant component and isolated vertices. As a graph sampled
from the uniform probability space of $d$-regular graphs with high probability
is an expander and meets the additional constraints, this result strengthens a
recent result due to Greenhill, Holt and Wormald about vertex percolation on
random $d$-regular graphs. We conclude by showing that performing the above
described deletion process on graphs that expand sub-linear sets by an
unbounded expansion ratio, with high probability results in a connected
expander graph.


title: Electrically Tunable Spin Polarization in a Carbon-Nanotube Spin Diode

abstract:
  We have studied the current through a carbon nanotube quantum dot with one
ferromagnetic and one normal-metal lead. For the values of gate voltage at
which the normal lead is resonant with the single available non-degenerate
energy level on the dot, we observe a pronounced decrease in the current for
one bias direction. We show that this rectification is spin-dependent, and that
it stems from the interplay between the spin accumulation and the Coulomb
blockade on the quantum dot. Our results imply that the current is
spin-polarized for one direction of the bias, and that the degree of spin
polarization is fully and precisely tunable using the gate and bias voltages.
As the operation of this spin diode does not require high magnetic fields or
optics, it could be used as a building block for electrically controlled
spintronic devices.


title: Constant curvature foliations on asymptotically hyperbolic spaces

abstract:
  Let $(M,g)$ be an asymptotically hyperbolic manifold with a smooth conformal
compactification. We establish a general correspondence between semilinear
elliptic equations of scalar curvature type on $\del M$ and Weingarten
foliations in some neighbourhood of infinity in $M$. We focus mostly on
foliations where each leaf has constant mean curvature, though our results
apply equally well to foliations where the leaves have constant
$\sigma_k$-curvature. In particular, we prove the existence of a unique
foliation near infinity in any quasi-Fuchsian 3-manifold by surfaces with
constant Gauss curvature. There is a subtle interplay between the precise terms
in the expansion for $g$ and various properties of the foliation. Unlike other
recent works in this area, by Rigger \cite{Ri} and Neves-Tian \cite{NT1},
\cite{NT2}, we work in the context of conformally compact spaces, which are
more general than perturbations of the AdS-Schwarzschild space, but we do
assume a nondegeneracy condition.


title: On Boltzmann's genius and thermodynamics

abstract:
  A recent essay [1] reminds us of how richly Boltzmann deserves to be
admiringly commemorated for the originality of his ideas on the occasion of his
150th birthday. Without any doubt, the scientific community owes Boltzmann a
great debt of gratitude for his ingenious and pathfinding contributions.
However, the essay chooses to illustrate this important memorial by statements
and inferences that perhaps are questionable today even to Boltzmann himself. I
will comment only on three issues.


title: Scattering of single spikes

abstract:
  We apply the dressing method to a string solution given by a static string
wrapped around the equator of a three-sphere and find that the result is the
single spike solution recently discussed in the literature. Further application
of the method allows the construction of solutions with multiple spikes. In
particular we construct the solution describing the scattering of two single
spikes and compute the scattering phase shift. As a function of the dressing
parameters, the result is exactly the same as the one for the giant magnon, up
to non-logarithmic terms. This suggests that the single spikes should be
described by an integrable spin chain closely related to the one associated to
the giant magnons. The field theory interpretation of such spin chain however
is still unclear.


title:
Auto and crosscorrelograms for the spike response of LIF neurons with
  slow synapses

abstract:
  An analytical description of the response properties of simple but realistic
neuron models in the presence of noise is still lacking. We determine
completely up to the second order the firing statistics of a single and a pair
of leaky integrate-and-fire neurons (LIFs) receiving some common slowly
filtered white noise. In particular, the auto- and cross-correlation functions
of the output spike trains of pairs of cells are obtained from an improvement
of the adiabatic approximation introduced in \cite{Mor+04}. These two functions
define the firing variability and firing synchronization between neurons, and
are of much importance for understanding neuron communication.


title:
Freeness of equivariant cohomology and mutants of compactified
  representations

abstract:
  We survey generalisations of the Chang-Skjelbred Lemma for integral
coefficients. Moreover, we construct examples of manifolds with actions of tori
of rank > 2 whose equivariant cohomology is torsion-free, but not free. This
answers a question of Allday's. The "mutants" we construct are obtained from
compactified representations and involve Hopf bundles in a crucial way.


title:
Phase Transitions and Quantum Stabilization in Quantum Anharmonic
  Crystals

abstract:
  A unified theory of phase transitions and quantum effects in quantum
anharmonic crystals is presented. In its framework, the relationship between
these two phenomena is analyzed. The theory is based on the representation of
the model Gibbs states in terms of path measures (Euclidean Gibbs measures). It
covers the case of crystals without translation invariance, as well as the case
of asymmetric anharmonic potentials. The results obtained are compared with
those known in the literature.


title:
Comment on the article arXiv 0710.0349 by Chapoton et al. titled ``An
  operational calculus for the Mould operad''

abstract: This paper has been withdrawn.


title: The number of cliques in graphs of given order and size

abstract:
  Let k_r(n,m) denote the minimum number of r-cliques in graphs with n vertices
and m edges. For r=3,4 we give a lower bound on k_r(n,m) that approximates
k_r(n,m) with an error smaller than n^r/(n^2-2m). The solution is based on a
constraint minimization of certain multilinear forms. In our proof, a
combinatorial strategy is coupled with extensive analytical arguments.


title: Umbral Deformations on Discrete Spacetime

abstract:
  Given a minimum measurable length underlying spacetime, the latter may be
effectively regarded as discrete, at scales of order the Planck length. A
systematic discretization of continuum physics may be effected most efficiently
through the umbral deformation. General functionals yielding such deformations
at the level of solutions are furnished and illustrated, and broad features of
discrete oscillations and wave propagation are outlined.


title: A stability version of H\"older's inequality

abstract:
  We present a stability version of H\"older's inequality, incorporating an
extra term that measures the deviation from equality. Applications are given.


title: Entanglement on demand through time reordering

abstract:
  Entangled photons can be generated "on demand" in a novel scheme involving
unitary time reordering of the photons emitted in a radiative decay cascade.
The scheme yields polarization entangled photon pairs, even though prior to
reordering the emitted photons carry significant "which path information" and
their polarizations are unentangled. This shows that quantum chronology can be
manipulated in a way that is lossless and deterministic (unitary). The theory
can, in principle, be tested and applied to the biexciton cascade in
semiconductor quantum dots.


title: Glueballs in Flatland

abstract:
  The pure gauge theory in 2+1 dimensions is explored, through both a
phenomenological model and a lattice calculation. The Isgur-Paton model is
extended to include a curvature term and various mixing mechanisms. The method
of inferential statistics is used to extract the parameters of best fit and to
compare the likelihoods of the various models when compared to existing lattice
data. The conventional assignment of spin 0 to the pseudoscalar state is called
into question by the proximity of a spin 4 state in the model, which motivates
calculating the mass of the spin 4 state on the lattice. Novel lattice
operators are constructed from a matrix of effective Greens functions which
attempt to overcome the lattice rotational ambiguities. Correlation functions
are presented for the channels with even J, and effective masses extracted. The
resulting masses compare well with the extended Isgur-Paton model.


title: Integrability of Rough Almost Complex Structures

abstract:
  We extend the Newlander-Nirenberg theorem to manifolds with almost complex
structures that have somewhat less than Lipschitz regularity. We also discuss
the regularity of local holomorphic coordinates in the integrable case, with
particular attention to Lipschitz almost complex structures.


title: Testing Benson's Regularity Conjecture

abstract:
  D. J. Benson conjectures that the Castelnuovo-Mumford regularity of a group
cohomology ring is always zero. More generally he conjectures that the
cohomology ring always has a system of parameters satisfying a property he
calls very strong quasi-regular. Using computer calculations we find that the
more general conjecture holds for all groups of order less than 256.


title: Supercriticality of a Class of Critical String Cosmological Solutions

abstract:
  For a class of Friedmann-Robertson-Walker type string solutions with compact
hyperbolic spatial slices formulated in critical dimension, we find the world
sheet conformal field theory which involves the linear dilaton and
Wess-Zumino-Witten type model with the compact hyperbolic target space. By
analyzing the infrared spectrum, we conclude that the theory is actually
supercritical due to the modular invariance of string theory. Thus, taking into
account previous results, we conclude that all the simple nontrivial string
cosmological solutions are supercritical. A possible explanation of why we are
living in D=4 is provided. The interesting relation of this background with the
Supercritical String Cosmology (SSC) is pointed out.


title:
Super-Reflection in Fluid Discs: Corotation Amplifier, Corotation
  Resonance, Rossby Waves, and Overstable Modes

abstract:
  In differentially rotating discs with no self-gravity, density waves cannot
propagate around the corotation, where the wave pattern rotation speed equals
the fluid rotation rate. Waves incident upon the corotation barrier may be
super-reflected (commonly referred to as corotation amplifier), but the
reflection can be strongly affected by wave absorptions at the corotation
resonance/singularity. The sign of the absorption is related to the Rossby wave
zone very near the corotation radius. We derive the explicit expressions for
the complex reflection and transmission coefficients, taking into account wave
absorption at the corotation resonance. We show that for generic discs, this
absorption plays a much more important role than wave transmission across the
corotation barrier. Depending on the sign of the gradient of the specific
vorticity of the disc the corotation resonance can either enhance or diminish
the super-reflectivity, and this can be understood in terms of the location of
the Rossby wave zone relative to the corotation radius. Our results provide the
explicit conditions (in terms of disc thickness, rotation profile and specific
vorticity gradient) for which super-reflection can be achieved. Global
overstable disc modes may be possible for discs with super-reflection at the
corotation barrier.


title: A Flattened Protostellar Envelope in Absorption around L1157

abstract:
  Deep Spitzer IRAC images of L1157 reveal many of the details of the outflow
and the circumstellar environment of this Class 0 protostar. In IRAC band 4, 8
microns, there is a flattened structure seen in absorption against the
background emission. The structure is perpendicular to the outflow and is
extended to a diameter of 2 arcminutes. This structure is the first clear
detection of a flattened circumstellar envelope or pseudo-disk around a Class 0
protostar. Such a flattened morphology is an expected outcome for many collapse
theories that include magnetic fields or rotation. We construct an extinction
model for a power-law density profile, but we do not constrain the density
power-law index.


title: Universal Mandelbrot Set as a Model of Phase Transition Theory

abstract:
  The study of Mandelbrot Sets (MS) is a promising new approach to the phase
transition theory. We suggest two improvements which drastically simplify the
construction of MS. They could be used to modify the existing computer programs
so that they start building MS properly not only for the simplest families.
This allows us to add one more parameter to the base function of MS and
demonstrate that this is not enough to make the phase diagram connected

categories: nlin.CD cond-mat.stat-mech hep-th math.CV math.DS


title: The Complex Frobenius Theorem for Rough Involutive Structures

abstract:
  We establish a version of the complex Frobenius theorem in the context of a
complex subbundle S of the complexified tangent bundle of a manifold, having
minimal regularity. If the subbundle S defines the structure of a Levi-flat
CR-manifold, it suffices that S be Lipschitz for our results to apply. A
principal tool in the analysis is a precise version of the Newlander-Nirenberg
theorem with parameters, for integrable almost complex structures with minimal
regularity, which builds on previous recent work of the authors.


title:
Numerical simulation of excitation of solar oscillation modes for
  different turbulent models

abstract:
  The goal of this research is to investigate how well various turbulence
models can describe physical properties of the upper convective boundary layer
of the Sun. An accurate modeling of the turbulence motions is necessary for
understanding the excitation mechanisms of solar oscillation modes. We have
carried out realistic numerical simulations using several different physical
Large Eddy Simulation (LES) models (Hyperviscosity approach, Smagorinsky, and
dynamic models) to investigate how the differences in turbulence modeling
affect the damping and excitation of the oscillations and their spectral
properties and compare with observations. We have first calculated the
oscillation power spectra of radial and non-radial modes supported by the
computational box with the different turbulence models. Then we have calculated
the work integral input to the modes to estimate the influence of the
turbulence model on the depth and strength of the oscillation sources. We have
compared these results with previous studies and with the observed properties
of solar oscillations. We find that the dynamic turbulence model provides the
best agreement with the helioseismic observations.


title: Planetesimal Formation with Particle Feedback

abstract:
  Proposed mechanisms for the formation of km-sized solid planetesimals face
long-standing difficulties. Robust sticking mechanisms that would produce
planetesimals by coagulation alone remain elusive. The gravitational collapse
of smaller solids into planetesimals is opposed by stirring from turbulent gas.
This proceeding describes recent works showing that "particle feedback," the
back-reaction of drag forces on the gas in protoplanetary disks, promotes
particle clumping as seeds for gravitational collapse. The idealized streaming
instability demonstrates the basic ability of feedback to generate particle
overdensities. More detailed numerical simulations show that the particle
overdensities produced in turbulent flows trigger gravitational collapse to
planetesimals. We discuss surprising aspects of this work, including the large
(super-Ceres) mass of the collapsing bound cluster, and the finding that MHD
turbulence aids gravitational collapse.


title: Weyl's law in the theory of automorphic forms

abstract:
  For a compact Riemannian manifold, Weyl's law describes the asymptotic
behavior of the counting function of the eigenvalues of the associated Laplace
operator. In this paper we discuss Weyl's law in the context of automorphic
forms. The underlying manifolds are locally symmetric spaces of finite volume.
In the non-compact case Weyl's law is closely related to the problem of
existence of cusp forms.


title: Random walk delayed on percolation clusters

abstract:
  We study a continuous time random walk on the $d$-dimensional lattice,
subject to a drift and an attraction to large clusters of a subcritical
Bernoulli site percolation. We find two distinct regimes: a ballistic one, and
a subballistic one taking place when the attraction is strong enough. We
identify the speed in the former case, and the algebraic rate of escape in the
latter case. Finally, we discuss the diffusive behavior in the case of zero
drift and weak attraction.


title:
Acoustic Probing of the Jamming Transition in an Unconsolidated Granular
  Medium

abstract:
  Experiments with acoustic waves guided along the mechanically free surface of
an unconsolidated granular packed structure provide information on the
elasticity of granular media at very low pressures that are naturally
controlled by the gravitational acceleration and the depth beneath the surface.
Comparison of the determined dispersion relations for guided surface acoustic
modes with a theoretical model reveals the dependencies of the elastic moduli
of the granular medium on pressure. The experiments confirm recent theoretical
predictions that relaxation of the disordered granular packing through
non-affine motion leads to a peculiar scaling of shear rigidity with pressure
near the jamming transition corresponding to zero pressure. Unexpectedly, and
in disagreement with the most of the available theories, the bulk modulus
depends on pressure in a very similar way to the shear modulus.


title: Long-living superpartners in the MSSM

abstract:
  The parameter space of the Constrained Minimal supersymmetric Standard Model
is considered. It is shown that for the particular choice of parameters there
are some regions where long-living charged superparticles exist. Two regions of
interest are the co-annihilation region with light staus, and the region with
large negative trilinear scalar coupling A distinguished by light stops. The
phenomenology of long-living superparticles is briefly discussed.


title:
The role of spin noise in the detection of nanoscale ensembles of
  nuclear spins

abstract:
  When probing nuclear spins in materials on the nanometer scale, random
fluctuations of the spin polarization will exceed the mean Boltzmann
polarization for sample volumes below about (100nm)^3. In this work, we use
magnetic resonance force microscopy to observe nuclear spin fluctuations in
real time. We show how reproducible measurements of the polarization variance
can be obtained by controlling the spin correlation time and rapidly sampling a
large number of independent spin configurations. A protocol to periodically
randomize the spin ensemble is demonstrated, allowing significant improvement
in the signal-to-noise ratio for nanometer-scale magnetic resonance imaging.


title: Study of $\psi(2S)$ decays into $\gamma K^+K^-$ and $\gamma \pi^+\pi^-$

abstract:
  Radiative charmonium decays from the BESII sample of 14$\times10^{6}$
$\psi(2S)$-events into two different final states, $\gamma K^+K^-$ and
$\gamma\pi^+\pi^-$, are analyzed. Product branching fractions for
$\psi(2S)\to\gamma X\to \gamma\pi^+\pi^-$, $\gamma K^+K^-$ are given, where
$X=f_2(1270)$, $f_0(1500)$, and $f_0(1710)$ in $\pi^+\pi^-$ and $f_2(1270)$,
$f_2'(1525)$, and $f_0(1700)$ in $K^+K^-$. An angular analysis gives the ratios
of the helicity projections for the $f_2(1270)$ in $\psi(2S)\to\gamma
f_2(1270)\to\gamma\pi^+\pi^-$.


title:
SU(5) Completion of the Dark Scalar Doublet Model of Radiative Neutrino
  Mass

abstract:
  Adding a second scalar doublet (eta^+,eta^0) and three neutral singlet
fermions N_{1,2,3} to the Standard Model of particle interactions with a new
Z_2 symmetry, it has been shown that eta^0_R or eta^0_I is a good dark-matter
candidate and seesaw neutrino masses are generated radiatively. A minimal
extension of this new idea is proposed to allow for its SU(5) completion.
Supersymmetric unification is then possible, and leptoquarks of a special kind
are predicted at the TeV scale.


title: The resultant on compact Riemann surfaces

abstract:
  We introduce a notion of resultant of two meromorphic functions on a compact
Riemann surface and demonstrate its usefulness in several respects. For
example, we exhibit several integral formulas for the resultant, relate it to
potential theory and give explicit formulas for the algebraic dependence
between two meromorphic functions on a compact Riemann surface. As a particular
application, the exponential transform of a quadrature domain in the complex
plane is expressed in terms of the resultant of two meromorphic functions on
the Schottky double of the domain.


title:
Theory of shot noise in single-walled metallic carbon nanotubes weakly
  coupled to nonmagnetic and ferromagnetic leads

abstract:
  We present theoretical study of shot noise in single wall metallic carbon
nanotubes weakly coupled to either nonmagnetic or ferromagnetic leads. Using
the real-time diagrammatic technique, we calculate the current, Fano factor and
tunnel magnetoresistance in the sequential tunneling regime. It is shown that
the differential conductance displays characteristic four-fold periodicity,
indicating single-electron charging. Such a periodicity is also visible in
tunnel magnetoresistance of the system as well as in the Fano factor. The
present studies elucidate the impact of ferromagnetic (vs. nonmagnetic)
contacts on the transport characteristics under consideration.


title: An approach to the finitistic dimension conjecture

abstract:
  Let $R$ be a finite dimensional $k$-algebra over an algebraically closed
field $k$ and $\mathrm{mod} R$ be the category of all finitely generated left
$R$-modules. For a given full subcategory $\mathcal{X}$ of $\mathrm{mod} R,$ we
denote by $\pfd \mathcal{X}$ the projective finitistic dimension of
$\mathcal{X}.$ That is, $\pfd \mathcal{X}:=\mathrm{sup} \{\pd X :
X\in\mathcal{X} \text{and} \pd X<\infty\}.$ \
  It was conjectured by H. Bass in the 60's that the projective finitistic
dimension $\pfd (R):=\pfd (\mathrm{mod} R)$ has to be finite. Since then, much
work has been done toward the proof of this conjecture. Recently, K. Igusa and
J. Todorov defined a function $\Psi:\mathrm{mod} R\to \Bbb{N},$ which turned
out to be useful to prove that $\pfd (R)$ is finite for some classes of
algebras. In order to have a different approach to the finitistic dimension
conjecture, we propose to consider a class of full subcategories of
$\mathrm{mod} R$ instead of a class of algebras, namely to take the class of
categories $\F(\theta)$ of $\theta$-filtered $R$-modules for all stratifying
systems $(\theta,\leq)$ in $\mathrm{mod} R.$


title: Magnetic Moment of Vector Mesons in the Background Field Method

abstract:
  We report some results for the magnetic moments of vector mesons extracted
from mass shifts in the presence of static external magnetic fields. The
calculations are done on $24^4$ quenched lattices using standard Wilson
actions, with $\beta$=6.0 and pion mass down to 500 MeV. The results are
compared to those from the form factor method.


title: On NIP and invariant measures

abstract:
  We study forking, Lascar strong types, Keisler measures and definable groups,
under an assumption of $NIP$ (not the independence property), continuing
aspects of math.LO/0607442. Among key results are: (i) if $p = tp(b/A)$ does
not fork over $A$ then the Lascar strong type of $b$ over $A$ coincides with
the compact strong type of $b$ over $A$ and any global nonforking extension of
$p$ is Borel definable over $bdd(A)$ (ii) analogous statements for Keisler
measures and definable groups, including the fact that $G^{000} = G^{00}$ for
$G$ definably amenable, (iii) definitions, characterizations and properties of
"generically stable" types and groups (iv) uniqueness of translation invariant
Keisler measures on groups with finitely satisfiable generics (vi) A proof of
the compact domination conjecture for definably compact commutative groups in
$o$-minimal expansions of real closed fields.


title:
On the energy growth of some periodically driven quantum systems with
  shrinking gaps in the spectrum

abstract:
  We consider quantum Hamiltonians of the form H(t)=H+V(t) where the spectrum
of H is semibounded and discrete, and the eigenvalues behave as E_n~n^\alpha,
with 0<\alpha<1. In particular, the gaps between successive eigenvalues decay
as n^{\alpha-1}. V(t) is supposed to be periodic, bounded, continuously
differentiable in the strong sense and such that the matrix entries with
respect to the spectral decomposition of H obey the estimate
|V(t)_{m,n}|<=\epsilon*|m-n|^{-p}max{m,n}^{-2\gamma} for m!=n where \epsilon>0,
p>=1 and \gamma=(1-\alpha)/2. We show that the energy diffusion exponent can be
arbitrarily small provided p is sufficiently large and \epsilon is small
enough. More precisely, for any initial condition \Psi\in Dom(H^{1/2}), the
diffusion of energy is bounded from above as <H>_\Psi(t)=O(t^\sigma) where
\sigma=\alpha/(2\ceil{p-1}\gamma-1/2). As an application we consider the
Hamiltonian H(t)=|p|^\alpha+\epsilon*v(\theta,t) on L^2(S^1,d\theta) which was
discussed earlier in the literature by Howland.


title:
Application of the RMF mass model to the r-process and the influence of
  mass uncertainties

abstract:
  A new mass table calculated by the relativistic mean field approach with the
state-dependent BCS method for the pairing correlation is applied for the first
time to study r-process nucleosynthesis. The solar r-process abundance is well
reproduced within a waiting-point approximation approach. Using an exponential
fitting procedure to find the required astrophysical conditions, the influence
of mass uncertainty is investigated. R-process calculations using the FRDM,
ETFSI-Q and HFB-13 mass tables have been used for that purpose. It is found
that the nuclear physical uncertainty can significantly influence the deduced
astrophysical conditions for the r-process site. In addition, the influence of
the shell closure and shape transition have been examined in detail in the
r-process simulations.


title:
Time delay and magnification centroid due to gravitational lensing by
  black holes and naked singularities

abstract:
  We model the massive dark object at the center of the Galaxy as a
Schwarzschild black hole as well as Janis-Newman-Winicour naked singularities,
characterized by the mass and scalar charge parameters, and study gravitational
lensing (particularly time delay, magnification centroid, and total
magnification) by them. We find that the lensing features are qualitatively
similar (though quantitatively different) for the Schwarzschild black holes,
weakly naked, and marginally strongly naked singularities. However, the lensing
characteristics of strongly naked singularities are qualitatively very
different from those due the Schwarzschild black holes. The images produced by
Schwarzschild black hole lenses and weakly naked and marginally strongly naked
singularity lenses always have positive time delays. On the other hand, the
strongly naked singularity lenses can give rise to images with positive, zero,
or negative time delays. In particular, for a large angular source position the
direct image (the outermost image on the same side as the source) due to
strongly naked singularity lensing always has negative time delay. We also
found that the scalar field decreases the time delay and increases the
magnitude of magnifications of images; this result could have important
implications for cosmology. As the Janis-Newman-Winicour metric also describes
the exterior gravitational field of a scalar star, naked singularities as well
as scalar star lenses, if these exist in nature, will serve as more efficient
cosmic telescopes than regular gravitational lenses.


title:
Off-center impurity in alkali halides: reorientation, electric
  polarization and pairing to F center. III. Numerical calculations

abstract:
  We carried out numerical calculations by an extended-Hueckel program in order
to check the analytical results reported in the preceding Part I and Part II.
We typically consider alkali halide clusters composed of some tens of
constituent atoms to calculate electronic energies under static conditions or
versus the displacements of particular atoms. Among other things, the
off-center displacement of substitutional Li+ impurity in most alkali halides
is evidenced. The trigonometric profile of the rotational barriers is also
confirmed for KCl.


title:
A template bank for gravitational waveforms from coalescing binary black
  holes: non-spinning binaries

abstract:
  Gravitational waveforms from the inspiral and ring-down stages of the binary
black hole coalescences can be modelled accurately by
approximation/perturbation techniques in general relativity. Recent progress in
numerical relativity has enabled us to model also the non-perturbative merger
phase of the binary black-hole coalescence problem. This enables us to
\emph{coherently} search for all three stages of the coalescence of
non-spinning binary black holes using a single template bank. Taking our
motivation from these results, we propose a family of template waveforms which
can model the inspiral, merger, and ring-down stages of the coalescence of
non-spinning binary black holes that follow quasi-circular inspiral. This
two-dimensional template family is explicitly parametrized by the physical
parameters of the binary. We show that the template family is not only
\emph{effectual} in detecting the signals from black hole coalescences, but
also \emph{faithful} in estimating the parameters of the binary. We compare the
sensitivity of a search (in the context of different ground-based
interferometers) using all three stages of the black hole coalescence with
other template-based searches which look for individual stages separately. We
find that the proposed search is significantly more sensitive than other
template-based searches for a substantial mass-range, potentially bringing
about remarkable improvement in the event-rate of ground-based interferometers.
As part of this work, we also prescribe a general procedure to construct
interpolated template banks using non-spinning black hole waveforms produced by
numerical relativity.


title: Constraints on mSUGRA through entropy and abundance criteria

abstract:
  We derive an expression for the entropy of a present dark matter halo
described by a Navarro-Frenk-White modified model with a central core. The
comparison of this entropy with the one of the halo at the freeze-out era
allows us to obtain an expression for the relic abundance of neutralinos, which
in turn is used to constrain the parameter space in mSUGRA models, when used
with the WMAP observations. Moreover, by joning these results with the ones
obtained from the usual abundance criteria, we are able to clearly discriminate
validity regions among tan beta values of the mSUGRA model, by demanding both
criteria to be consistent with the 2 sigma bounds of the WMAP observations for
the relic density: 0.112 < Omega h^2 < 0.122. We found that for sign mu
positive, small values of tan beta are not favored; only for tan beta ~ 50 are
both criteria significantly consistent. The use of both criteria also allows us
to put a lower bound on the neutralino mass of > 151 GeV.


title:
Instanton representation of Plebanski gravity. Euclidean signature
  minisuperspace solution

abstract:
  Using the action for the instanton representation of Plebanski gravity
(IRPG), we construct minisuperspace solutions restricted to diagonal variables.
We have treated the Euclidean signature case with zero cosmological constant,
depicting a gravitational analogy to free particle motion. This paper provides
a testing ground for the IRPG for a simple case, which will be extended to the
full theory in future work.


title: Constraining Cosmic Evolution of Type Ia Supernovae

abstract:
  We present the first large-scale effort of creating composite spectra of
high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift
counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88
high-redshift SNe Ia with excellent light-curve information. In addition, we
have obtained 397 spectra of low-redshift SNe through a multiple-decade effort
at Lick and Keck Observatories, and we have used 45 UV spectra obtained by
HST/IUE. The low-redshift spectra act as a control sample when comparing to the
ESSENCE spectra. In all instances, the ESSENCE and Lick composite spectra
appear very similar. The addition of galaxy light to the Lick composite spectra
allows a nearly perfect match of the overall spectral-energy distribution with
the ESSENCE composite spectra, indicating that the high-redshift SNe are more
contaminated with host-galaxy light than their low-redshift counterparts. This
is caused by observing objects at all redshifts with the same slit width, which
corresponds to different projected distances. After correcting for the
galaxy-light contamination, subtle differences in the spectra remain. We have
estimated the systematic errors when using current spectral templates for
K-corrections to be ~0.02 mag. The variance in the composite spectra give an
estimate of the intrinsic variance in low-redshift maximum-light SN spectra of
~3% in the optical and growing toward the UV. The difference between the
maximum light low and high-redshift spectra constrain SN evolution between our
samples to be < 10% in the rest-frame optical.