title:
A Cyclic Operad in the Category of Artin Stacks and Gravitational
  Correlators

abstract:
  We define an Artin stack which may be considered as a substitute for the
non-existing (or empty) moduli space of stable two-pointed curves of genus
zero. We show that this Artin stack can be viewed as the first term of a cyclic
operad in the category of stacks. Applying the homology functor we obtain a
linear cyclic operad. We formulate conjectures which assert that cohomology of
a smooth projective variety has the structure of an algebra over this homology
operad and that gravitational quantum cohomology can naturally expressed in
terms of this algebra. As a test for these conjectures we show how certain
well-known relations between gravitational correlators can be deduced from
them.


title:
Local electron and ionic heating effects on the conductance of
  nanostructures

abstract:
  Heat production and dissipation induced by current flow in nanostructures is
of primary importance to understand the stability of these systems. These
effects have contributions from both electron-phonon and electron-electron
interactions. Here, we consider the effect of the local electron and ionic
heating on the conductance of nanoscale systems. Specifically we show that the
non-linear dependence of the conductance on the external bias may be used to
infer information about the local heating of both electrons and ions. We
compare our results with available experimental data on transport in
$\mathrm{D}_2$ and $\mathrm{H}_2$ molecules. The comparison between experiment
and theory is reasonably good close to the lowest phonon mode of the molecule,
especially for the $\mathrm{D}_2$ molecule. At higher biases we cannot rule out
the presence of other effects like, e.g., current-induced forces that make the
scenario more complex.


title:
Limits on Primordial Non-Gaussianity from Minkowski Functionals of the
  WMAP Temperature Anisotropies

abstract:
  We present an analysis of the Minkowski Functionals (MFs) describing the WMAP
three-year temperature maps to place limits on possible levels of primordial
non-Gaussianity. In particular, we apply perturbative formulae for the MFs to
give constraints on the usual non-linear coupling constant fNL. The theoretical
predictions are found to agree with the MFs of simulated CMB maps including the
full effects of radiative transfer. The agreement is also very good even when
the simulation maps include various observational artifacts, including the
pixel window function, beam smearing, inhomogeneous noise and the survey mask.
We find accordingly that these analytical formulae can be applied directly to
observational measurements of fNL without relying on non-Gaussian simulations.
Considering the bin-to-bin covariance of the MFs in WMAP in a chi-square
analysis, we find that the primordial non-Gaussianity parameter is constrained
to lie in the range -70<fNL<91 at 95% C.L. using the Q+V+W co-added maps.


title: A Spitzer study of star-forming regions in Virgo Cluster galaxies

abstract:
  We present a preliminary study of the star formation distribution within
three Virgo Cluster galaxies using the 24 micron Spitzer observations from the
Spitzer Survey of Virgo (SPITSOV) in combination with H-alpha observations. The
purpose of our study is to explore the relationship between the star formation
distribution within galaxies and the type (and phase) of interactions
experienced within the cluster environment. Neither highly-obscured star
formation nor strongly enhanced star-forming regions along the leading edges of
galaxies experiencing ICM-ISM interactions were found. However, very unobscured
star-forming regions were found in the outer parts of one galaxy (NGC 4402),
while relatively obscured star-forming regions were found in the extraplanar
regions of another galaxy (NGC 4522). We attribute the observed differences
between NGC 4402 and NGC 4522 to the direction of motion of each galaxy through
the ICM.


title: Mirror-time diffusion discount model of options pricing

abstract:
  The proposed model modifies option pricing formulas for the basic case of
log-normal probability distribution providing correspondence to formulated
criteria of efficiency and completeness. The model is self-calibrating by
historic volatility data; it maintains the constant expected value at maturity
of the hedged instantaneously self-financing portfolio. The payoff variance
dependent on random stock price at maturity obtained under an equivalent
martingale measure is taken as a condition for introduced "mirror-time"
derivative diffusion discount process. Introduced ksi-return distribution,
correspondent to the found general solution of backward drift-diffusion
equation and normalized by theoretical diffusion coefficient, does not contain
so-called "long tails" and unbiased for considered 2004-2007 S&P 100 index
data. The model theoretically yields skews correspondent to practical term
structure for interest rate derivatives. The method allows increasing the
number of asset price probability distribution parameters.


title:
Electron thermalization and photon emission from magnetized compact
  sources

abstract:
  We present detailed calculations of the electron thermalization by
synchrotron self-absorption accounting for cooling by Compton scattering. For
the first time, we solve coupled kinetic equations for electrons and photons
without any approximations on the relevant cross-sections and compute
self-consistently the resulting electron and photon distributions. The results
presented in this contribution may be applied to the magnetized coronae around
Galactic black hole accretion disks.


title: Quantum Giant Magnons

abstract:
  The giant magnons are classical solitons of the O(N) sigma-model, which play
an important role in the AdS/CFT correspondence. We study quantum giant magnons
first at large N and then exactly using Bethe Ansatz, where giant magnons can
be interpreted as holes in the Fermi sea. We also identify a solvable limit of
Bethe Ansatz in which it describes a weakly-interacting Bose gas at zero
temperature. The examples include the O(N) model at large N, weakly interacting
non-linear Schrodinger model, and nearly isotropic XXZ spin chain in the
magnetic field.


title:
Multi-Channel Atomic Scattering and Confinement-Induced Resonances in
  Waveguides

abstract:
  We develop a grid method for multi-channel scattering of atoms in a waveguide
with harmonic confinement. This approach is employed to extensively analyze the
transverse excitations and deexcitations as well as resonant scattering
processes. Collisions of identical bosonic and fermionic as well as
distinguishable atoms in harmonic traps with a single frequency $\omega$
permitting the center-of-mass (c.m.) separation are explored in depth. In the
zero-energy limit and single mode regime we reproduce the well-known
confinement-induced resonances (CIRs) for bosonic, fermionic and heteronuclear
collisions. In case of the multi-mode regime up to four open transverse
channels are considered. Previously obtained analytical results are extended
significantly here. Series of Feshbach resonances in the transmission behaviour
are identified and analyzed. The behaviour of the transmission with varying
energy and scattering lengths is discussed in detail. The dual CIR leading to a
complete quantum suppression of atomic scattering is revealed in multi-channel
scattering processes. Possible applications include, e.g., cold and ultracold
atom-atom collisions in atomic waveguides and electron-impurity scattering in
quantum wires.


title: Cohomological support loci for Abel-Prym curves

abstract:
  For an Abel-Prym curve contained in a Prym variety, we determine the
cohomological support loci of its twisted ideal sheaves and the dimension of
its theta-dual.


title:
Multiplayer Quantum Games and its Application as Access Controller in
  Architecture of Quantum Computers

abstract:
  One of the basics tasks in computer systems is the control of access of
resources. Basically, there is a finite amount of resources that can be, for
example, the CPU, memory or I/O ports, and several processes requiring those
resources. If there is not enough resource in order to attend the demand, some
kind of control access has to be employed. In this work, recognizing the
resource sharing problem as a competition, we employ a simplified multiplayer
quantum game as an access controller. The proposed quantum game can be employed
in the architecture of quantum computers.


title: On the relation between $E(5)-$models and the interacting boson model

abstract:
  The connections between the $E(5)-$models (the original E(5) using an
infinite square well, $E(5)-\beta^4$, $E(5)-\beta^6$ and $E(5)-\beta^8$), based
on particular solutions of the geometrical Bohr Hamiltonian with
$\gamma$-unstable potentials, and the interacting boson model (IBM) are
explored. For that purpose, the general IBM Hamiltonian for the $U(5)-O(6)$
transition line is used and a numerical fit to the different $E(5)-$models
energies is performed, later on the obtained wavefunctions are used to
calculate B(E2) transition rates. It is shown that within the IBM one can
reproduce very well all these $E(5)-$models. The agreement is the best for
$E(5)-\beta^4$ and reduces when passing through $E(5)-\beta^6$, $E(5)-\beta^8$
and E(5), where the worst agreement is obtained (although still very good for a
restricted set of lowest lying states). The fitted IBM Hamiltonians correspond
to energy surfaces close to those expected for the critical point. A phenomenon
similar to the quasidynamical symmetry is observed.


title:
Electronic structure and ferromagnetic behavior in the
  $Mn_{1-x}A_xAs_{1-y}B_y$ alloys

abstract:
  In this work, a systematic ab initio study of the influence of doping on
electronic structure and local magnetic moments of ferromagnetic MnAs has been
carried out. The majority of the considered substitution elements, potentially
suitable for modification of MnAs as working material of magnetic refrigerators
is shown to result in reduction of the ferromagnetic moment. But there are
variants of anionic substitution (for example, substitution of As for S and Se)
when the magnetic moment grows.


title: The single-atom box: bosonic staircase and effects of parity

abstract:
  We have developed a theory of a Josephson junction formed by two
tunnel-coupled Bose-Einstein condensates in a double-well potential in the
regime of strong atom-atom interaction for an arbitrary total number $N$ of
bosons in the condensates. The tunnel resonances in the junction are shown to
be periodically spaced by the interaction energy, forming a single-atom
staircase sensitive to the parity of $N$ even for large $N$. One of the
manifestations of the staircase structure is the periodic modulation with the
bias energy of the visibility of the interference pattern in lattices of
junctions.


title: Lecture Notes on CMB Theory: From Nucleosynthesis to Recombination

abstract:
  These lecture notes comprise an informal but pedagogical introduction to the
well established physics and phenomenology of the cosmic microwave background
(CMB) between big bang nucleosynthesis and recombination. The dominant
properties of the spectrum, temperature anisotropy and polarization anisotropy
of the CMB all arise from this period. We review the physical processes
involved and show how they are related to the observed phenomenology.


title:
Chemical abundances and gas content in disk galaxies: correlations with
  the $\lambda$ spin parameter

abstract:
  By using a very simple and general model to describe the dynamics of disk
galaxies, we estimate the $\lambda$ spin parameter for a sample of observed
galaxies and present a study in which we show that several important physical
properties are intrinsically related to the dynamics of the systems. Although
correlations between average metallicity with magnitude or Hubble type are
evident, we obtain equally strong correlations with the spin parameter, where
galaxies with low $\lambda $ values present higher abundances and galaxies with
high $\lambda$ values are poor in metals. Also, the gas content of the galaxies
correlates with $\lambda$, with high $\lambda$ systems showing higher gas mass
fractions than low $\lambda$ galaxies, highlighting the important role this
parameter plays in the structure of disk galaxies and the proposal of $\lambda$
as a robust and objective physical measure of galactic morphology.


title: On variance stabilisation by double Rao-Blackwellisation

abstract:
  Population Monte Carlo has been introduced as a sequential importance
sampling technique to overcome poor fit of the importance function. In this
paper, we compare the performances of the original Population Monte Carlo
algorithm with a modified version that eliminates the influence of the
transition particle via a double Rao-Blackwellisation. This modification is
shown to improve the exploration of the modes through an large simulation
experiment on posterior distributions of mean mixtures of distributions.


title: A Characterization of Jacobians by the Existence of Picard Bundles

abstract:
  Based on the Matsusaka-Ran criterion we give a criterion to characterize when
a principal polarized abelian variety is a Jacobian by the existence of Picard
bundles.


title:
NLTE Model of NGC 6543's Central Star and its Relation with the
  Surrounding Planetary Nebula

abstract:
  We analyze the chemical composition of the central star of the planetary
nebula NGC 6543 based upon a detailed NLTE model of its stellar wind. The
logarithmic abundances by number are H=12.00, He=11.00, C=9.03, N=8.36, O=9.02,
Si=8.19, P=5.53, S=7.57 and Fe=7.24. Compared with the solar abundances, most
of the elements have solar composition with respect to hydrogen except C which
is overabundant by 0.28 dex and Fe which is depleted by $\sim 0.2$ dex.
Contrary to most previous work, we find that the star is not H-poor and has a
normal He composition. These abundances are compared with those found in the
diffuse X-ray plasma and the nebular gas. Compared to the plasma emitting in
diffuse X-rays, the stellar wind is much less depleted in iron. Since the iron
depletions in the nebular gas and X-ray plasma are similar, we conclude that
the plasma emitting diffuse X-rays is derived from the nebular gas rather than
the stellar wind. Excellent agreement is obtained between the abundances in the
stellar wind and the nebular recombination line abundances for He, C, and O
relative to H. On the other hand, the derived stellar N abundance is smaller
than the nebular N abundance derived from recombination lines and agrees with
the abundance found from collisionally-excited lines. The mean temperature
variation determined by five different methods indicates that the difference in
the nebular abundances between the recombination lines and collisionally
excited lines can be explained as due to the temperature variations in a
chemically homogeneous medium.


title: Collective modes and electromagnetic response of a chiral superconductor

abstract:
  Motivated by the recent controversy surrounding the Kerr effect measurements
in strontium ruthenate \cite{xia:167002}, we examine the electromagnetic
response of a clean chiral p-wave superconductor. When the contributions of the
collective modes are accounted for, the Hall response in a clean chiral
superconductor is smaller by several orders of magnitude than previous
theoretical predictions and is too small to explain the experiment. We also
uncover some unusual features of the collective modes of a chiral
superconductor, namely, that they are not purely longitudinal and couple to
external transverse fields.


title: Fluctuation Theorem and Chaos

abstract:
  The heat theorem (i.e. the second law of thermodynamics or the existence of
entropy) is a manifestation of a general property of hamiltonian mechanics and
of the ergodic Hypothesis. In nonequilibrium thermodynamics of stationary
states the chaotic hypothesis plays a similar role: it allows a unique
determination of the probability distribution (called {\rm SRB} distribution on
phase space providing the time averages of the observables. It also implies an
expression for a few averages concrete enough to derive consequences of
symmetry properties like the fluctuation theorem or to formulate a theory of
coarse graining unifying the foundations of equilibrium and of nonequilibrium.


title:
The Impact of Galaxy Cluster Mergers on Cosmological Parameter
  Estimation from Surveys of the Sunyaev-Zel'dovich Effect

abstract:
  Sensitive surveys of the Cosmic Microwave Background will detect thousands of
galaxy clusters via the Sunyaev-Zel'dovich (SZ) effect. Two SZ observables, the
central or maximum and integrated Comptonization parameters y_max and Y, relate
in a simple way to the total cluster mass, which allow the construction of mass
functions (MFs) that can be used to estimate cosmological parameters such as
Omega_M, sigma_8, and the dark energy parameter w. However, clusters form from
the mergers of smaller structures, events that can disrupt the equilibrium of
intracluster gas upon which SZ-M relations rely. From a set of
N-body/hydrodynamical simulations of binary cluster mergers, we calculate the
evolution of Y and y_max over the course of merger events and find that both
parameters are transiently "boosted," primarily during the first core passage.
We then use a semi-analytic technique developed by Randall et al. (2002) to
estimate the effect of merger boosts on the distribution functions YF and yF of
Y and y_max, respectively, via cluster merger histories determined from
extended Press-Schechter (PS) merger trees. We find that boosts do not induce
an overall systematic effect on YFs, and the values of Omega_M, sigma_8, and w
were returned to within 2% of values expected from the nonboosted YFs. The
boosted yFs are significantly biased, however, causing Omega_M to be
underestimated by 15-45%, sigma_8 to be overestimated by 10-25%, and w to be
pushed to more negative values by 25-45%. We confirm that the integrated SZ
effect, Y, is far more robust to mergers than y_max, as previously reported by
Motl et al. (2005) and similarly found for the X-ray equivalent Y_X, and we
conclude that Y is the superior choice for constraining cosmological
parameters.


title:
The impact of nebular emission on the broadband fluxes of high-redshift
  galaxies

abstract:
  A substantial fraction of the light emitted from young or star-forming
galaxies at ultraviolet to near-infrared wavelengths comes from the ionized
interstellar medium in the form of emission lines and a nebular continuum. At
high redshifts, star formation rates are on average higher and stellar
populations younger than in the local Universe. Both of these effects act to
boost the impact of nebular emission on the overall spectrum of galaxies. Even
so, the broadband fluxes and colours of high-redshift galaxies are routinely
analyzed under the assumption that the light observed originates directly from
stars. Here, we assess the impact of nebular emission on broadband fluxes in
Johnson/Cousins BVRIJHK, Sloan Digital Sky Survey griz and Spitzer IRAC/MIPS
filters as a function of observed redshift (up to z=15) for galaxies with
different star formation histories. We find that nebular emission may account
for a non-negligible fraction of the light received from high-redshift
galaxies. The ages and masses inferred for such objects through the use of
spectral evolutionary models that omit the nebular contribution are therefore
likely to contain systematic errors. We argue that a careful treatment of the
nebular component will be essential for the interpretation of the rest-frame
ultraviolet-to-infrared properties of the first galaxies formed, like the ones
expected to be detected with the James Webb Space Telescope.


title: The Intrinsic Fraction of Broad Absorption Line Quasars

abstract:
  We carefully reconsider the problem of classifying broad absorption line
quasars (BALQSOs) and derive a new, unbiased estimate of the intrinsic BALQSO
fraction from the SDSS DR3 QSO catalogue. We first show that the distribution
of objects selected by the so-called ``absorption index'' (AI) is clearly
bimodal in log(AI), with only one mode corresponding to definite BALQSOs. The
surprisingly high BALQSO fractions that have recently been inferred from
AI-based samples are therefore likely to be overestimated. We then present two
new approaches to the classification problem that are designed to be more
robust than the AI, but also more complete than the traditional ``balnicity
index'' (BI). Both approaches yield observed BALQSO fractions around 13.5 per
cent, while a conservative third approach suggests an upper limit of 18.3 per
cent. Finally, we discuss the selection biases that affect our observed BALQSO
fraction. After correcting for these biases, we arrive at our final estimate of
the intrinsic BALQSO fraction. This is f_BALQSO = 0.17 +/- 0.01 (stat) +/- 0.03
(sys), with an upper limit of f_BALQSO = 0.23. We conclude by pointing out that
the bimodality of the log(AI) distribution may be evidence that the BAL-forming
region has clearly delineated physical boundaries.


title:
SPHRAY: A Smoothed Particle Hydrodynamics Ray Tracer for Radiative
  Transfer

abstract:
  We introduce SPHRAY, a Smoothed Particle Hydrodynamics (SPH) ray tracer
designed to solve the 3D, time dependent, radiative transfer (RT) equations for
arbitrary density fields. The SPH nature of SPHRAY makes the incorporation of
separate hydrodynamics and gravity solvers very natural. SPHRAY relies on a
Monte Carlo (MC) ray tracing scheme that does not interpolate the SPH particles
onto a grid but instead integrates directly through the SPH kernels. Given
initial conditions and a description of the sources of ionizing radiation, the
code will calculate the non-equilibrium ionization state (HI, HII, HeI, HeII,
HeIII, e) and temperature (internal energy/entropy) of each SPH particle. The
sources of radiation can include point like objects, diffuse recombination
radiation, and a background field from outside the computational volume. The MC
ray tracing implementation allows for the quick introduction of new physics and
is parallelization friendly. A quick Axis Aligned Bounding Box (AABB) test
taken from computer graphics applications allows for the acceleration of the
raytracing component. We present the algorithms used in SPHRAY and verify the
code by performing all the test problems detailed in the recent Radiative
Transfer Comparison Project of Iliev et. al. The Fortran 90 source code for
SPHRAY and example SPH density fields are made available on a companion website
(www.sphray.org).


title:
Status of Oscillation plus Decay of Atmospheric and Long-Baseline
  Neutrinos

abstract:
  We study the interplay of neutrino oscillation and invisible decay in
atmospheric and long-baseline neutrinos experiments. We perform a global
analysis of the full atmospheric data from Super-Kamiokande together with
long-baseline K2K and MINOS in these scenarios. We find that the admixture of
nu_mu -> nu_tau oscillations with parameters Delta_m32^2 = 2.6e-3 eV^2 and
theta_23 ~ 34 degrees plus decay of the heavy neutrino, nu_3, with lifetime of
the order tau_3/m_3 ~ 2.6e-12 s/eV provides a reasonable fit to atmospheric
neutrinos, although this solution becomes more disfavored (dropping to the 99%
CL) once long-baseline data are included. Other than this local minimum, the
analysis shows no evidence in favor of a non-vanishing neutrino decay width and
an lower bound on the decay lifetime tau_3/m_3 > 9.3e-11 s/eV is set at 99% CL.
In the framework of Majoron models, this constraint can be translated into a
bound on the Majoron coupling to nu_3 and an unmixed very light sterile state,
|g_s3| < 8.6e-3 (2.2 eV/m_3).


title:
The Effect of Thermal Neutrino Motion on the Non-linear Cosmological
  Matter Power Spectrum

abstract:
  We have performed detailed studies of non-linear structure formation in
cosmological models with light neutrinos. For the first time the effect of
neutrino thermal velocities has been included in a consistent way, and the
effect on the matter power spectrum is found to be significant. The effect is
large enough to be measured in future, high precision surveys. Additionally, we
provide a simple but accurate analytic expression for the suppression of
fluctuation power due to massive neutrinos. Finally, we describe a simple and
fast method for including the effect of massive neutrinos in large-scale N-body
simulations which is accurate at the 1% level for \sum m_nu < 0.15 eV.


title:
The Hobby-Eberly Telescope "Chemical Abundances of Stars in the Halo"
  (CASH) Project. I. The Lithium-, s-, and r-Enhanced Metal-Poor Giant HKII
  17435-00532

abstract:
  We present the first detailed abundance analysis of the metal-poor giant HKII
17435-00532. This star was observed as part of the University of Texas
long-term project "Chemical Abundances of Stars in the Halo" (CASH). A spectrum
was obtained with the High Resolution Spectrograph (HRS) on the Hobby-Eberly
Telescope with a resolving power of R~15,000. Our analysis reveals that this
star may be located on the red giant branch, red horizontal branch, or early
asymptotic giant branch. We find that this metal-poor ([Fe/H]=-2.2) star has an
unusually high lithium abundance (log eps (Li)=+2.1), mild carbon ([C/Fe]=+0.7)
and sodium ([Na/Fe]=+0.6) enhancement, as well as enhancement of both s-process
([Ba/Fe]=+0.8) and r-process ([Eu/Fe]=+0.5) material. The high Li abundance can
be explained by self-enrichment through extra mixing that connects the
convective envelope with the outer regions of the H-burning shell. If so, HKII
17435-00532 is the most metal-poor star in which this short-lived phase of Li
enrichment has been observed. The Na and n-capture enrichment can be explained
by mass transfer from a companion that passed through the thermally-pulsing AGB
phase of evolution with only a small initial enrichment of r-process material
present in the birth cloud. Despite the current non-detection of radial
velocity variations (over ~180 days), it is possible that HKII 17435-00532 is
in a long-period or highly-inclined binary system, similar to other stars with
similar n-capture enrichment patterns.


title: Extra Gauge Invariance from an Extra Dimension

abstract:
  We describe higher-dimensional theories whose low-energy 4D descriptions
contain larger gauge or global symmetry groups. As an example, we construct a
Higgsless SU(2) x U(1) model of electroweak symmetry breaking. The 5D SU(2)
gauge invariance contains both the weak SU(2) gauge group and a custodial
symmetry that protects the rho parameter. Fermions obtain isospin-violating
masses while maintaining universal gauge couplings among all three generations.
As a further example, we construct a model of chiral color based on a single
SU(3).


title: On incidence algebras description of cobweb posets

abstract:
  The explicite formulas for Mobius function and some other important elements
of the incidence algebra of an arbitrary cobweb poset are delivered. For that
to do one uses Kwasniewski's construction of his cobweb posets . The digraph
representation of these cobweb posets constitutes a newly discovered class of
orderable DAG's named here down KoDAGs with a kind of universality now being
investigated. Namely cobweb posets' and thus KoDAGs's defining di-bicliques are
links of any complete relations' chains.


title: Binary Lenses in OGLE III EWS Database. Season 2005

abstract:
  We present nine new binary lens candidates from OGLE-III Early Warning System
database for the season of 2005. We have also found four events interpreted as
single mass lensing of double sources. The candidates have been selected by
visual light curves inspection. Examining the models of binary lenses in our
previous studies (10 caustic crossing events of OGLE-II seasons 1997--1999 and
34 binary lens events of OGLE-III seasons 2002--2004, including one planetary
event), in this work and in three publications concerning planetary events of
season 2005, we find four cases of extreme mass ratio binaries (q<0.01), and
almost all other models with mass ratios in the range 0.1<q<1.0, which may
indicate the division between planetary systems and binary stars.


title: MgII Line Variability of High Luminosity Quasars

abstract:
  We monitored five high-luminosity quasars with lambda L_{3000A} > 10^45 erg
s^-1 at 0.4 < z < 0.6 to measure flux variability of the MgII 2798 line and
explore feasibility of reverberation mapping using MgII. Over the two year
monitoring program, imaging data were obtained with the A Noble Double-Imaging
Camera on the 1.3-m telescope at the Cerro Tololo Inter-American Observatory
(CTIO), while spectroscopic data were obtained at the same night with the R-C
spectrograph on the 1.5-m telescope at the CTIO. By performing differencial
photometry using available field stars in each quasar image, we measured
variability -- 10%-24% peak-to-peak changes and 3%-8% rms variations -- in the
B band, which includes flux changes in the rest-frame UV continuum (~2500A --
~3600A) as well as the MgII line. Utilizing photometric measurements for
spectroscopic flux calibration, we measured the MgII line flux and the
continuum flux at 3000\AA from each single-epoch spectrum. Four objects showed
MgII line flux variability with 23%-50% peak-to-peak changes and 8%-17% rms
variations over 1-1.5 year rest-frame time scales, while one object showed no
MgII flux variability within the measurement error (<5%). We also detected
4%-15% rms variations of the MgII line width for all five objects. With
synchronous observations for photometry and spectroscopy, we demonstrated the
feasibility of the MgII line reverberation mapping for high-luminosity quasars
at intermediate redshift.


title:
A new lagrangian particle method to describe turbulent flows of fully
  compressible ideal gases

abstract:
  There are several approaches to describe flows with particles e.g.
Lattice-Gas Automata (LGA), Lattice-Boltzmann method (LBM) or smoothed particle
hydrodynamics (SPH). These approaches do not use fixed grids on which the
Navier-Stokes equations are solved via e.g. finite volume method. The flow is
simulated using a multitude of particles or particle density distributions,
which interacts and due to statistical laws and an even more fundamental
approach than the Navier-Stokes equation, the averaged flow variables can be
derived. After a short summary of the most popular particle methods the new
DMPC (Dissipative Multiple Particles Collision) approach will be presented. The
DMPC-model eliminates some of the weak points of the established particle
methods and shows high potential for more accurate CFD solution especially in
areas where standard CFD tools still have problems (e.g. aero-acoustics). The
DMPC-model deals with discrete circular particles and calculates the detailed
collision process (micro scale) of several overlapping particles. With
thermodynamic, statistical and similarity laws global (large scale) flow
variables can be derived. The model is so far 2d and the particles can move in
every direction in the 2d plane depending on the forces acting on it. The
possible overlap between neighbouring particles and multi-particle interactions
are important features of this model. A freeware software is developed and
published under www.cfd2k.eu. There the executable, the user guide and several
exemplary cases can be downloaded.


title: Rings and Jets around PSR J2021+3651: the `Dragonfly Nebula'

abstract:
  We describe recent Chandra ACIS observations of the Vela-like pulsar PSR
J2021+3651 and its pulsar wind nebula (PWN). This `Dragonfly Nebula' displays
an axisymmetric morphology, with bright inner jets, a double-ridged inner
nebula, and a ~30" polar jet. The PWN is embedded in faint diffuse emission: a
bow shock-like structure with standoff ~1' brackets the pulsar to the east and
emission trails off westward for 3-4'. Thermal (kT=0.16 +/-0.02 keV) and power
law emission are detected from the pulsar. The nebular X-rays show spectral
steepening from Gamma=1.5 in the equatorial torus to Gamma=1.9 in the outer
nebula, suggesting synchrotron burn-off. A fit to the `Dragonfly' structure
suggests a large (86 +/-1 degree) inclination with a double equatorial torus.
Vela is currently the only other PWN showing such double structure. The >12 kpc
distance implied by the pulsar dispersion measure is not supported by the X-ray
data; spectral, scale and efficiency arguments suggest a more modest 3-4 kpc.


title: A Torelli theorem for curves over finite fields

abstract:
  We study hyperbolic curves and their Jacobians over finite fields in the
context of anabelian geometry.


title: Optical Measurement of the Phase-Breaking Length in Graphene

abstract:
  This paper reports the experimental determination of the phase-breaking
length L of conduction electrons in graphene using Raman spectroscopy. Based on
the double-resonance model, we extract L from the spatial dependence of the D
band susceptibility near the graphene edge. By using prior knowledge of sample
properties and the excitation point-spread function we are able to determine
the spatial variation of the Raman susceptibilities with high accuracy, and the
results reveal a phase-breaking length L~40nm near the graphene edge.


title: Paramagnetic Intrinsic Meissner Effect in Layered Superconductors

abstract:
  Free energy of a layered superconductor with $\xi_{\perp} < d$ is calculated
in a parallel magnetic field by means of the Gor'kov equations, where
$\xi_{\perp}$ is a coherence length perpendicular to the layers and $d$ is an
inter-layer distance. The free energy is shown to differ from that in the
textbook Lawrence-Doniach model at high fields, where the Meissner currents are
found to create an unexpected positive magnetic moment due to shrinking of the
Cooper pairs "sizes" by a magnetic field. This paramagnetic intrinsic Meissner
effect in a bulk is suggested to detect by measuring in-plane torque, the upper
critical field, and magnetization in layered organic and high-T$_c$
superconductors as well as in superconducting superlattices.


title: A non-spherical mass outflow from RS Oph during its 2006 outburst

abstract:
  We present results of our modeling the H-alpha line profile along the 2006 RS
Oph outburst. At day 1.38 the very broad component of the H-alpha profile was
possible to fit by a bipolar wind model. The model corresponds to a very fast
acceleration of the wind particles, and the line luminosity of about 2900
(d/1.6 kpc)^2 solar luminosities to the mass-loss rate of around (1-2) x 10E-4
solar masses per year. During days 10-30 the broad component shrank to FWZI =
1800 km/s. It could be associated with expanding ring and its satellite
components at about +/- 2430 km/s with bipolar jets. Later observations made at
day 57 and 209 indicated a decrease in both the mass-loss rate (1xE-5 - 1xE-6
solar masses per year) and the wind acceleration. During the quiet phase,
emission bumps observed sporadically in the line wings could reflect clumpy
ejections by the central star.


title:
Matters of Gravity, The Newsletter of the Topical Group in Gravitation
  of the American Physical Society, Volume 31, Winter 2008

abstract:
  GGR News: GGR program at the APS meeting in St. Louis we hear that... by
David Garfinkle 100 years ago, by David Garfinkle
  Research Briefs: The Torsion Pendulum's Contribution to Dark Energy, by Bill
Hamilton
  Conference Reports: 10th Capra Meeting on Radiation Reaction, by Carlos
Sopuerta Quantum Gravity in the Southern Cone IV, by Rafael A. Porto


title: Self-Consistent Theory of Halo Mergers - II: CDM Power Spectra

abstract:
  We place additional constraints on the three parameters of the dark matter
halo merger rate function recently proposed by Parkinson, Cole & Helly by
utilizing Smoluchowski's coagulation equation, which must be obeyed by any
binary merging process which conserves mass. We find that the constraints from
Smoluchowski's equation are degenerate, limiting to a thin plane in the three
dimensional parameter space. This constraint is consistent with those obtained
from fitting to N-body measures of progenitor mass functions, and provides a
better match to the evolution of the overall dark matter halo mass function,
particularly for the most massive halos. We demonstrate that the proposed
merger rate function does not permit an exact solution of Smoluchowski's
equation and, therefore, the choice of parameters must reflect a compromise
between fitting various parts of the mass function. The techniques described
herein are applicable to more general merger rate functions, which may permit a
more accurate solution of Smoluchowski's equation. The current merger rate
solutions are most probably sufficiently accurate for the vast majority of
applications.


title:
Scale interactions and scaling laws in rotating flows at moderate Rossby
  numbers and large Reynolds numbers

abstract:
  The effect of rotation is considered to become important when the Rossby
number is sufficiently small, as is the case in many geophysical and
astrophysical flows. Here we present direct numerical simulations to study the
effect of rotation in flows with moderate Rossby numbers (down to Ro~0.1) but
at Reynolds numbers large enough to observe the beginning of a turbulent
scaling at scales smaller than the energy injection scale. We use coherent
forcing at intermediate scales, leaving enough room in the spectral space for
an inverse cascade of energy to also develop. We analyze the spectral behavior
of the simulations, the shell-to-shell energy transfer, scaling laws, and
intermittency, as well as the geometry of the structures in the flow. At late
times, the direct transfer of energy at small scales is mediated by
interactions with the largest scale in the system, the energy containing eddies
with k_perp~1, where "perp" refers to wavevectors perpendicular the axis of
rotation. The transfer between modes with wavevector parallel to the rotation
is strongly quenched. The inverse cascade of energy at scales larger than the
energy injection scale is non-local, and energy is transferred directly from
small scales to the largest available scale. Also, as time evolves and the
energy piles up at the large scales, the intermittency of the direct cascade of
energy is preserved while corrections due to intermittency are found to be the
same (within error bars) as in homogeneous turbulence.


title:
New Physics at the LHC: A Les Houches Report. Physics at Tev Colliders
  2007 -- New Physics Working Group

abstract:
  We present a collection of signatures for physics beyond the standard model
that need to be explored at the LHC. The signatures are organized according to
the experimental objects that appear in the final state, and in particular the
number of high pT leptons. Our report, which includes brief experimental and
theoretical reviews as well as original results, summarizes the activities of
the "New Physics'' working group for the "Physics at TeV Colliders" workshop
(Les Houches, France, 11-29 June, 2007).


title:
Measurement of the electron-pressure profile of galaxy clusters in
  Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data

abstract:
  Using WMAP 3-year data at the locations of close to $\sim 700$ X-ray selected
clusters we have detected the amplitude of the thermal Sunyaev-Zeldovich (TSZ)
effect at the 15$\sigma$ level, the highest statistical significance reported
so far. Owing to the large size of our cluster sample, we are able to detect
the corresponding CMB distortions out to large cluster-centric radii. The
region over which the TSZ signal is detected is, on average, four times larger
in radius than the X-ray emitting region, extending to $\sim 3h_{70}^{-1}$Mpc.
We show that an isothermal $\beta$ model does not fit the electron pressure at
large radii; instead, the baryon profile is consistent with the
Navarro-Frenk-White profile, expected for dark matter in the concordance
$\Lambda$CDM model. The X-ray temperature at the virial radius of the clusters
falls by a factor $\sim 3-4$ from the central value, depending on the cluster
concentration parameter. Our results suggest that cluster dynamics at large
radii is dominated by dark matter and is well described by Newtonian gravity.


title: Current-induced spin torques in III-V ferromagnetic semiconductors

abstract:
  We formulate a theory of current-induced spin torques in inhomogeneous III-V
ferromagnetic semiconductors. The carrier spin-3/2 and large spin-orbit
interaction, leading to spin non-conservation, introduce significant conceptual
differences from spin torques in ferromagnetic metals. We determine the spin
density in an electric field in the weak momentum scattering regime,
demonstrating that the torque on the magnetization is intimately related to
spin precession under the action of both the spin-orbit interaction and the
exchange field characteristic of ferromagnetism. The spin polarization excited
by the electric field is smaller than in ferromagnetic metals and, due to lack
of angular momentum conservation, cannot be expressed in a simple closed
vectorial form. Remarkably, scalar and spin-dependent scattering do not affect
the result. We use our results to estimate the velocity of current-driven
domain walls.


title: Preventing Coordinated Attacks Via Distributed Alert Exchange

abstract:
  Attacks on information systems followed by intrusions may cause large revenue
losses. The prevention of both is not always possible by just considering
information from isolated sources of the network. A global view of the whole
system is necessary to recognize and react to the different actions of such an
attack. The design and deployment of a decentralized system targeted at
detecting as well as reacting to information system attacks might benefit from
the loose coupling realized by publish/subscribe middleware. In this paper, we
present the advantages and convenience in using this communication paradigm for
a general decentralized attack prevention framework. Furthermore, we present
the design and implementation of our approach based on existing
publish/subscribe middleware and evaluate our approach for GNU/Linux systems.


title: Loop groups and string topology

abstract:
  Survey article on loop groups and their representations, following a course
of three lectures held at the summer school "algebraic groups" at the
Georg-August-Universitaet zu Goettingen, June 27--July 13, 2005.
  We discuss loop groups, their central extensions, and positive energy
representations.


title: Response of Holographic QCD to Electric and Magnetic Fields

abstract:
  We study the response of the Sakai-Sugimoto holographic model of large N_c
QCD at nonzero temperature to external electric and magnetic fields. In the
electric case we find a first-order insulator-conductor transition in both the
confining and deconfining phases of the model. In the deconfining phase the
conductor is described by the parallel 8-brane-anti-8-brane embedding with a
current of quarks and anti-quarks. We compute the conductivity and show that it
agrees precisely with a computation using the Kubo formula. In the confining
phase we propose a new kind of 8-brane embedding, corresponding to a baryonic
conductor. In the magnetic field case we show that the critical temperature for
chiral-symmetry restoration in the deconfined phase increases with the field
and approaches a finite value in the limit of an infinite magnetic field. We
also illustrate the nonlinear behavior of the electric and magnetic
susceptibilities in the different phases.


title: Fluidic Electrodynamics: a new approach to EM Propulsion

abstract:
  We report on a new methodological approach to electrodynamics based on a
fluidic viewpoint. We develop a systematic approach establishing analogies
between physical magnitudes and isomorphism (structure-preserving mappings)
between systems of equations. This methodological approach allows us to give a
general expression for the hydromotive force, thus re-obtaining the
Navier-Stokes equation departing from the an appropriate electromotive force.
  From this ground we offer a fluidic approach to different kind of issues with
interest in propulsion, e.g., the force exerted by a charged particle on a body
carrying current; the magnetic force between two parallel currents; the
Magnus's force. It is shown how the intermingle between the fluid vectors
fields and electromagnetic fields lead to new insights on their dynamics. The
new concepts introduced in this work suggest possible applications to
electromagnetic (EM) propulsion devices and the mastery of the principles of
producing electric fields of required configuration in plasma medium.


title:
X-ray and $\gamma$-ray propagation in bent crystals with flat and
  cylindrical surfaces

abstract:
  In this paper we investigate x-ray and $\gamma$-ray propagation in crystals
having a constant strain gradient and flat or cylindrical surfaces. When a
displacement field is present, we solve the Takagi-Taupin equations either by
the Riemann-Green method or by a numerical method. We apply the results to
study the operation of a double-crystal Laue-Laue diffractometer having a flat
collimating crystal followed by a bent analyzer crystal. In particular, we
examine the effect of the analyzer strain on the location of the diffraction
peaks in the dispersive and non-dispersive setup, thus confirming our
previously reported peak-location as being set only by the diffracting plane
spacing on the analyzer entrance surface.


title:
Absolute Calibration and Characterization of the Multiband Imaging
  Photometer for Spitzer: IV. The Spectral Energy Distribution Mode

abstract:
  The Spectral Energy Distribution (SED) mode of the Multiband Imaging
Photometer for Spitzer (MIPS) Space Telescope provides low-spectral resolution
(R ~ 15-25) spectroscopy in the far infrared using the MIPS 70 um detector. A
reflective grating provides a dispersion of 1.7 um per pixel, and an effective
wavelength coverage of 52.8--98.7 um over detector rows 1-27. The final 5
detector rows are contaminated by second-order diffracted light and are left
uncalibrated. The flux calibration is based on observations of MIPS calibration
stars with 70 um flux densities of 0.5--15 Jy. The point-source flux
calibration accuracy is estimated to be 10% or better down to about 0.5 Jy at
the blue end of the spectrum and to 2 Jy near the red end. With additional
uncertainties from the illumination and aperture corrections included, the
surface brightness calibration of extended sources is accurate to ~15%.
Repeatability of better than 5% is found for the SED mode through multiple
measurements of several calibration stars.


title:
The Chandra ACIS Survey of M33 (ChASeM33): Transient X-ray Sources
  Discovered in M33

abstract:
  The Chandra ACIS Survey of M33 (ChASeM33) has acquired 7 fields of ACIS data
covering M33 with 200 ks of exposure in each field. A catalog from the first 10
months of data, along with archival Chandra observations dating back to the
year 2000, is currently available. We have searched these data for transient
sources that are measured to have a 0.35-8.0 keV unabsorbed luminosity of at
least 4$\times10^{35}$ erg s$^{-1}$ in one epoch and are not detected in
another epoch. This set of the survey data has yielded seven such sources,
including one previously-known supersoft source. We analyzed XMM-Newton data
from the archive distributed over the years 2000 to 2003 to search for
recurrent outbursts and to get a spectrum for the supersoft transient. We find
only one recurrent transient in our sample. The X-ray spectra, light curves,
and optical counterpart candidates of two of the other sources suggest that
they are high-mass X-ray binaries. Archival Spitzer photometry and high X-ray
absorption suggest that one of the sources is a highly variable background
active galactic nucleus. The other three sources are more difficult to
classify. The bright transient population of M33 appears to contain a large
fraction of high-mass X-ray binaries compared with the transient populations of
M31 and the Galaxy, reflecting the later morphology of M33.


title: Test of Anomaly Mediation at the LHC

abstract:
  In the anomaly-mediated supersymmetry breaking model with the assumption of
the generic form of Kahler potential, gauginos are the only kinematically
accessible superparticles to the LHC. We consider the LHC phenomenology of such
a model assuming that the gluino is lighter than 1 TeV. We show that a
significant number of charged Winos, which may travel O(10 cm) before the
decay, are produced from the gluino production processes. Thus, in this class
of model, it will be very important to search for short charged tracks using
inner detectors. We also show that, if a large number of the charged Wino
tracks are identified, the lifetime of the charged Wino can be measured, which
provides us a test of anomaly mediation.


title: The Color Bimodality in Galaxy Clusters since z = 0.9

abstract:
  We present the evolution of the color-magnitude distribution of galaxy
clusters from z = 0.45 to z = 0.9 using a homogeneously selected sample of
~1000 clusters drawn from the Red-Sequence Cluster Survey (RCS). The red
fraction of galaxies decreases as a function of increasing redshift for all
cluster-centric radii, consistent with the Butcher-Oemler effect, and
suggesting that the cluster blue population may be identified with newly
infalling galaxies. We also find that the red fraction at the core has a
shallower evolution compared with that at the cluster outskirts. Detailed
examination of the color distribution of blue galaxies suggests that they have
colors consistent with normal spirals and may redden slightly with time.
Galaxies of starburst spectral type contribute less than 5% of the increase in
the blue population at high redshift, implying that the observed Butcher-Oemler
effect is not caused by a unobscured starbursts, but is more consistent with a
normal coeval field population.


abstract:
  The next to leading order (NLO) QCD corrections to J/psi polarization of
hadronproduction at Tevatron and LHC are calculated. The results show that the
J/psi polarization is extremely changed from more transversal polarization at
leading order (LO) into more longitudinal polarization at NLO. Although it
gives more longitudinal polarization than the recent experimental result on the
J/psi polarization at Tevatron. It sheds light on the solution to the large
discrepancy of J/psi polarization between theoretical predication and
experimental measurement, and suggests that the next important step is to
calculate the NLO correction for color octet state J/psi^{(8)}
hadronproduction. Our calculations are performed in two ways where the
polarizations are summed analytically or not, and they are checked with each
other. It also gives a K factor for total cross section (ratio of NLO to LO) of
about 2 and shows that the NLO corrections boost the J/psi production for about
2 order of magnitude in high transverse momentum p_t region of J/psi, which
confirms the calculation by Campbell, Maltoni and Tramontano.


title: A Nuclear Magnetic Resonance Study on Rubrene-cobalt Nano-composites

abstract:
  We implemented a nuclear magnetic resonance (NMR) study on rubrene(C42H28)-Co
nano-composites that exhibit an enhanced magnetoresistance (MR) ratio of 80%.
The 59Co NMR spin echo experiment enabled clarification of the hyperfine field
of Co at the interface between the ferromagnet and the molecules, which has not
been investigated for molecular spintronics. An enhanced hyperfine field of the
Co was observed in the rubrene-Co nano-composites, which may be related to the
enhancement of the MR ratio. This study demonstrates the importance of
microscopic investigation of the interface between molecules and ferromagnets
that governs spin-dependent transport in molecular spin devices.


title:
Problems in the theory of thermal Casimir force between dielectrics and
  semiconductors

abstract:
  The application of the Lifshitz theory to describe the thermal Casimir force
between dielectrics and semiconductors is considered. It is shown that for all
true dielectrics (i.e., for all materials having zero conductivity at zero
temperature) the inclusion of a nonzero conductivity arising at nonzero
temperature into the model of dielectric response leads to the violation of the
Nernst heat theorem. This result refers equally to simple insulators, intrinsic
semiconductors, Mott-Hubbard dielectrics and doped semiconductors with doping
concentration below a critical value. We demonstrate that in the
insulator-metal transition the Casimir free energy changes abruptly
irrespective of whether the conductivity changes continuously or
discontinuously. The application of the Lifshitz formula to polar dielectrics
results in large thermal correction that is linear in temperature. A rule is
formulated on how to apply the Lifshitz theory to real materials in agreement
with thermodynamics and experiment.


title:
The Lyman-alpha forest at redshifts 0.1 -- 1.6: good agreement between a
  large hydrodynamic simulation and HST spectra

abstract:
  We give a comprehensive statistical description of the Lyman-alpha absorption
from the intergalactic medium in a hydrodynamic simulation at redshifts
0.1-1.6, the range of redshifts covered by HST spectra of QSOs. We use the ENZO
code to make a 76 comoving Mpc cube simulation using 75 kpc cells, for a Hubble
constant of 71 km/s/Mpc. The best prior work, by \citet{dave99},used an SPH
simulation in a 15.6 Mpc box with an effective resolution of 245 kpc and
slightly different cosmological parameters. At redshifts z=2 this simulation is
different from data. \citet{tytler07b} found that the simulated spectra at z=2
have too little power on large scales, Lyman-alpha lines are too wide, there is
a lack high column density lines, and there is a lack of pixels with low flux.
Here we present statistics at z<1.6, including the flux distribution, the mean
flux, the effective opacity, and the power and correlation of the flux. We also
give statistics of the lyman alpha lines including the line width distribution,
the column density distribution, the number of lines per unit equivalent width
and redshift, and the correlation between the line width and column density. We
find that the mean amount of absorption in the simulated spectra changes
smoothly with redshift with DA(z)=0.01(1+z)^{2.25}. Both the trend and absolute
values are close to measurements of HST spectra by \citet{kirkman07a}. The
column density and line width distributions are also close to those measured
from HST spectra by \citet{janknecht06a}, except for the mode of the line width
distribution which is smaller in the HST spectra. Although some differences
that we saw at z=2 are too subtle to be seen in existing HST spectra, overall,
the simulation gives an good description of HST spectra at 0.1<z<1.6.


title:
Non-Spherical Shapes of the Proton: Existence, Measurement and
  Computation

abstract:
  The nature of the proton wave function can be elucidated by studying the
matrix elements of spin-dependent quark density operators SDDs, defined as
matrix elements of density operators in proton states of definite
spin-polarization. These have an infinite variety of non-spherical shapes. The
matrix elements of the SDDs are closely related to specific transverse momentum
dependent TMD parton distributions accessible in the angular dependence of
certain semi-inclusive processes. New measurements would allow the direct
exhibition of the non-spherical nature of the proton. The TMDs can be computed
using lattice QCD so that the non-spherical shapes could eventually be measured
experimentally and computed using fundamental theory.


title:
Hollow carbon spheres as an efficient dopant for enhancing critical
  current density of MgB2 based tapes

abstract:
  A significant enhancement of Jc and Hirr in MgB2 tapes has been achieved by
the in situ powder-in-tube method utilizing hollow carbon spheres (HCS) as
dopants. At 4.2 K, the transport Jc for the 850C sintered samples reached
3.1x10^4, and 1.4x10^4 A/cm^2 at 10 and 12 T, respectively, and were better
than those of optimal nano-SiC doped tapes. Furthermore, the Hirr for doped
sample was raised up to 16.8 T at 10 K due to the carbon substitution effect.
The results demonstrate that HCS is one of the most promising dopants besides
nano-carbon and SiC for the enhancement of current capacity for MgB2 in high
fields.


title:
Experimental procedures for precision measurements of the Casimir force
  with an Atomic Force Microscope

abstract:
  Experimental methods and procedures required for precision measurements of
the Casimir force are presented. In particular, the best practices for
obtaining stable cantilevers, calibration of the cantilever, correction of
thermal and mechanical drift, measuring the contact separation, sphere radius
and the roughness are discussed.


title: Generic case complexity and One-Way functions

abstract:
  The goal of this paper is to introduce ideas and methodology of the generic
case complexity to cryptography community. This relatively new approach allows
one to analyze the behavior of an algorithm on ''most'' inputs in a simple and
intuitive fashion which has some practical advantages over classical methods
based on averaging. We present an alternative definition of one-way function
using the concepts of generic case complexity and show its equivalence to the
standard definition. In addition we demonstrate the convenience of the new
approach by giving a short proof that extending adversaries to a larger class
of partial algorithms with errors does not change the strength of the security
assumption.


title:
Energetics and Kinetics of Primary Charge Separation in Bacterial
  Photosynthesis

abstract:
  We report the results of Molecular Dynamics (MD) simulations and formal
modeling of the free energy surfaces and reaction rates of primary charge
separation in the reaction center of \textit{Rhodobacter sphaeroides}. Two
simulation protocols were used to produce MD trajectories. Standard force field
potentials were employed in the first protocol. In the second protocol, the
special pair was made polarizable to reproduce a high polarizability of its
photoexcited state observed by Stark spectroscopy. The charge distribution
between covalent and charge-transfer states of the special pair was dynamically
adjusted during the simulation run. We found from both protocols that the
breadth of electrostatic fluctuations of the protein/water environment far
exceeds previous estimates resulting in about 1.6 eV reorganization energy of
electron transfer in the first protocol and 2.5 eV in the second protocol. Most
of these electrostatic fluctuations become dynamically frozen on the time-scale
of primary charge separation resulting in much smaller solvation contributions
to the activation barrier. A non-ergodic formulation of the diffusion-reaction
electron transfer kinetics has allowed us to reproduce the experimental results
for both the temperature dependence of the rate and the non-exponential decay
of the population of the photoexcited special pair.


title: On a Latent Structure of Lepton Universality

abstract:
  The mass of an electroweakly charged lepton consists of the two components of
electric and weak nature, and regardless of the difference in masses, all
leptons have an equal charge, the same charge radius as well as an identical
magnetic moment. Between these currents there appear the most diverse
connections, for example, in their interactions with an electroweak field of
spinless nuclei. We derive the united equations which relate the structural
parts of mass to charge, charge radius and magnetic moment of each lepton as a
consequence of the ideas of flavor symmetry laws. Therefore, these ideas
require the verification of the lepton universality from the point of view of a
constancy of the size implied from the multiplication of a weak mass of lepton
by its electric mass. Such a principle gives the possibility to define the
lepton weak masses. If this picture does not change, leptons universally
interact not only with the photon or the weak boson but also with any of the
corresponding types of gauge fields.


title: Some arithmetic properties of matroidal ideals

abstract: In this paper, we study various properties of matroidal ideals.


title: Eta-mesic nuclei in relativistic mean-field theory

abstract:
  With the eta-nucleon (eta N) interaction Lagrangian deduced from chiral
perturbation theory, we study the possible eta-mesic nuclei in the framework of
relativistic mean-field theory. The eta single-particle energies are sensitive
to the eta N scattering length, and increase monotonically with the nucleon
number A. If the scattering length is in the range of a^{eta N}=0.75-1.05 fm
and the imaginary potential V_{0}-15 MeV, some discrete states of C, O and Ne
eta bound states should be identified in experiments. However, when the
scattering length a^{eta N}< 0.5 fm, or the imaginary potential V_{0} > 30 MeV,
no discrete eta meson bound states could be observed in experiments.


title:
Effects of heat dissipation on unipolar resistance switching in
  Pt/NiO/Pt capacitors

abstract:
  We fabricated Pt/NiO/Pt capacitor structures with various bottom electrode
thicknesses, $t_{BE}$, and investigated their resistance switching behaviors.
The capacitors with $t_{BE} \geq 50$ nm exhibited typical unipolar resistance
memory switching, while those with $t_{BE} \leq 30$ nm showed threshold
switching. This interesting phenomenon can be explained in terms of the
temperature-dependent stability of conducting filaments. In particular, the
thinner $t_{BE}$ makes dissipation of Joule heat less efficient, so the
filaments will be at a higher temperature and become less stable. This study
demonstrates the importance of heat dissipation in resistance random access
memory.


title:
Structure of A=138 isobars above the 132Sn core and the N-N interaction
  in the neutron-rich environment

abstract:
  Large basis untruncated shell model calculations have been done for the A=138
neutron -rich nuclei in the pi(gdsh) X nu(hfpi) valence space above the 132Sn
core. Two (1+2) -body nuclear Hamiltonians, viz., realistic CWG and empirical
SMPN in this model space have been used. Calculated ground state binding
energies, level spectra and other spectroscopic properties have been compared
with the available experimental data. Importance of untruncated shell model
calculations in this model space has been pointed out. Shell model results for
the very neutron rich Sn isotope (138Sn, N/Z=1.76) of astrophysical interest
for which no spectroscopic information except beta -decay half life is
available, have been presented. Shell structure and evolution of collectivity
in the even-even A=138 isobars have been studied as a function of valence
neutron and /or proton numbers. Calculations done for the first time, reproduce
remarkably well the collective vibrational states in 138Te and 138Xe.
Comparison of some of the important two-body matrix elements of the empirical
SMPN, CW5082 and the realistic CWG interactions has been done. These matrix
elements are important for ground state binding energies and low-lying spectra
of nuclei in this region. Consideration of the predictability of the two
interactions seems to suggest that, in order to incorporate the special
features of the N-N interaction in such exotic n-rich environment above the
132Sn core, the use of local spectroscopic information from the region might be
essential.


title: Three-nucleon interactions: A frontier in nuclear structure

abstract:
  Three-nucleon interactions are a frontier in understanding and predicting the
structure of strongly-interacting matter in laboratory nuclei and in the
cosmos. We present results and discuss the status of first calculations with
microscopic three-nucleon interactions beyond light nuclei. This coherent
effort is possible due to advances based on effective field theory and
renormalization group methods in nuclear physics.


title:
X-ray observations of the Coma Cluster in a broad energy band with
  INTEGRAL, RXTE, and ROSAT observatories

abstract:
  We present results of X-ray observations of the Coma cluster with multiple
instruments over a broad energy band. Using the data from INTEGRAL, RXTE and
ROSAT observatories, we find that the Coma spectrum in the 0.5-107 keV energy
band can be well approximated by a thermal plasma emission model with a
temperature of T=8.2 keV. INTEGRAL was used to image the cluster emission in
the hard energy band. The cluster is only marginally detectable ~1.6sigma in
the 44-107 keV energy band; however, the raw flux in this band is consistent
with the previous results from Beppo-SAX and RXTE observatories. We can exclude
with high significance that the hard-band flux reported by Beppo-SAX and RXTE
could be produced by a single point source. The 20-80 keV flux of a possible
non-thermal component in the cluster spectrum is (6.0+-8.8)*10**-12
ergs/cm^2/s. It is unlikely that the IC scattering of CMB photons is able to
produce hard X-ray flux at these levels, unless the magnetic field strength is
as low as 0.2muG. The latter value can be considered as a lower limit on the
field strength in Coma. We also present a temperature map of the central part
of the cluster, which shows significant variations and in particular, a hot,
~11.5 keV, region in the extension towards the subcluster infalling from the
South-West.


title: Study of Chemical Equilibration of a Baryon Rich QGP

abstract:
  Parton equilibration studies for thermally equilibrated but chemically
non-equilibrated quark-gluon-plasma (QGP), likely to be formed at the
relativistic colliders at BNL and CERN is presented.Parton equilibration is
studied enforcing baryon number conservation. Process like quark-flavor
interchanging is also taken into consideration.The degree of equilibration is
studied comparatively for the various reactions/ constraints that are being
considered.


title:
A microstructurally informed model for the mechanical response of
  three-dimensional actin networks

abstract:
  We propose a class of microstructurally informed models for the linear
elastic mechanical behavior of cross-linked polymer networks such as the actin
cytoskeleton. Salient features of the models include the possibility to
represent anisotropic mechanical behavior resulting from anisotropic filament
distributions, and a power-law scaling of the mechanical properties with the
filament density. Mechanical models within the class are parameterized by seven
different constants. We demonstrate a procedure for determining these constants
using finite element models of three-dimensional actin networks. Actin
filaments and cross-links were modeled as elastic rods, and the networks were
constructed at physiological volume fractions and at the scale of an image
voxel. We show the performance of the model in estimating the mechanical
behavior of the networks over a wide range of filament densities and degrees of
anisotropy.


title: Heterodimensional tangencies on cycles leading to strange attractors

abstract:
  In this paper, we study heterodimensional cycles of two-parameter families of
3-dimensional diffeomorphisms some element of which contains nondegenerate
heterodimensional tangencies of the stable and unstable manifolds of two saddle
points with different indexes, and prove that such diffeomorphisms can be well
approximated by another element which has a quadratic homoclinic tangency
associated to one of these saddle points. Moreover, it is shown that the
tangency unfolds generically with respect to the family. This result together
with some theorem in Viana, we detect strange attractors appeared arbitrarily
close to the original element with the heterodimensional cycle.


title: Information Hiding Techniques: A Tutorial Review

abstract:
  The purpose of this tutorial is to present an overview of various information
hiding techniques. A brief history of steganography is provided along with
techniques that were used to hide information. Text, image and audio based
information hiding techniques are discussed. This paper also provides a basic
introduction to digital watermarking.


title: Lower bound theorem for normal pseudomanifolds

abstract:
  In this paper we present a self-contained combinatorial proof of the lower
bound theorem for normal pseudomanifolds, including a treatment of the cases of
equality in this theorem. We also discuss McMullen and Walkup's generalised
lower bound conjecture for triangulated spheres in the context of the lower
bound theorem. Finally, we pose a new lower bound conjecture for non-simply
connected triangulated manifolds.


title: Information Filtering via Self-Consistent Refinement

abstract:
  Recommender systems are significant to help people deal with the world of
information explosion and overload. In this Letter, we develop a general
framework named self-consistent refinement and implement it be embedding two
representative recommendation algorithms: similarity-based and spectrum-based
methods. Numerical simulations on a benchmark data set demonstrate that the
present method converges fast and can provide quite better performance than the
standard methods.


title: Quantum walk on circles in phase space

abstract:
  We propose a variation of the quantum walk on a circle in phase space by
conjoining the Hadamard coin flip with simultaneous displacement of the
walker's location in phase space and show that this generalization is a proper
quantum walk albeit over multiple concentric circles in phase instead of just
over one circle. We motivate the conjoining of Hadamard and displacement
operations by showing that the Jaynes-Cummings model for coin+walker
approximately yields this description in the dispersive limit. The quantum walk
signature is evident in the phase distribution of the walker provided that
appropriate pulse durations are applied for each coin flip.


title:
Discovery of a New X-ray Filled Radio Supernova Remnant Around the
  Pulsar Wind Nebula in 3EG J1809-2328

abstract:
  We report the discovery of a partial ~2deg. diameter non-thermal radio shell
coincident with Taz, the pulsar wind nebula (PWN) in the error box of the
apparently variable gamma-ray source 3EG J1809-2328. We propose that this radio
shell is a newly identified supernova remnant (SNR G7.5-1.7) associated with
the PWN. The SNR surrounds an amorphous region of thermal X-rays detected in
archival ROSAT and ASCA observations putting this system in the
mixed-morphology class of supernova remnants. G7.5-1.7 is the fifth such
supernova remnant coincident with a bright GeV source, and the fourth
containing a pulsar wind nebulae.


title:
Interaction between scalar field and ideal fluid with inhomogeneous
  equation of state

abstract:
  In this letter we study a model of interaction between the scalar field and
an inhomogeneous ideal fluid. We have considered two forms of the ideal fluid
and a power law expansion for the scale factor. We have solved the equations
for the energy densities. Also we show that besides being a dark energy model
to explain the cosmic acceleration, this model shows a decaying nature of the
scalar field potential and the interaction parameter.


title:
The electric field of the Earth after the occurrence of the February
  14th, 2008, Ms = 6.7R EQ in Greece. Its implications towards the prediction
  of a probable future large EQ

abstract:
  The electric field of the Earth registered by three monitoring sites (ATH,
PYR, HIO) located in Greece, is investigated and analyzed after the occurrence
of the Methoni EQ (14th of February, 2008, Ms =6.7R). The period of analysis is
performed for 2 days (21st-22nd of February) and 7 days after the occurrence of
the main seismic event. The obtained results suggest that the seismogenic area
generates electrical signals denoting a specific epicentral area. This area
coincides with the already seismically activated area. An estimate for the time
of occurrence of this EQ is made by the application of the Oscillating
Lithospheric Plate Model. The analysis of the seismic potential of the regional
area suggests that the remaining stored seismic energy is capable of producing
a large earthquake in the same area. The expected maximum magnitude (Ms) of a
future earthquake which could take place in the same seismogenic area is
estimated as Ms = 7.24R by the application of the Lithospheric Seismic Energy
flow model.


title:
Interacting Quantum Dot Coupled to a Kondo Spin: A Universal Hamiltonian
  Study

abstract:
  We study a mesoscopic interacting quantum dot described by the "universal
Hamiltonian" that is coupled to a Kondo spin. The ferromagnetic exchange
interaction within the dot leads to a stepwise increase of the ground state
spin; this Stoner staircase is modified non-trivially by the Kondo interaction.
We find that the spin-transition steps move to lower values of the exchange
coupling for weak Kondo interaction, but shift back up for sufficiently strong
Kondo coupling. The problem is solved numerically by diagonalizing the system
Hamiltonian in a customized good-spin basis and analytically in the weak and
strong Kondo coupling limits. The interplay of Kondo and ferromagnetic exchange
can be probed with experimentally tunable parameters.


title: Spin transfer torques in magnetic tunnel junctions

abstract:
  This chapter presents a review on spin transfer torque in magnetic tunnel
junctions. In the first part, we propose an overview of experimental and
theoretical studies addressing current-induced magnetization excitations in
magnetic tunnel junctions. The most significant results are presented and the
main observable characteristics are discussed. A description of the mechanism
of spin transfer in ferromagnets is finally proposed. In the second part, a
quantum description of spin transport in magnetic tunnel junctions with
amorphous barrier is developed. The role of spin-dependent reflections as well
as electron incidence and spin-filtering by the barrier are described. We show
that these mechanisms give rise to specific properties of spin transfer in
tunnel junctions, very different from the case of metallic spin-valves. In the
third part, the theoretical observable features of spin transfer in magnetic
tunnel junctions are derived and the validity of these results is discussed and
compared to recent experiments. To conclude this chapter, we study the
mechanism of spin transfer in half-metallic tunnel junctions, expected to mimic
MgO-based magnetic tunnel junctions.


title:
Spatial fluorescence cross correlation spectroscopy by means of a
  spatial light modulator

abstract:
  Spatial Fluorescence Cross Correlation Spectroscopy is a rarely investigated
version of Fluorescence Correlation Spectroscopy, in which the fluorescence
signals from different observation volumes are cross-correlated. In the
reported experiments, two observation volumes, typically shifted by a few
$\mu$m, are produced, with a Spatial Light Modulator and two adjustable
pinholes. We illustrated the feasibility and potentiality of this technique by:
i) measuring molecular flows, in the range 0.2 - 1.5 $\mu$m/ms, of so-lutions
seeded with fluorescent nanobeads or rhodamine molecules (simulating active
transport phenomenons); ii) investigating the permeability of the
phospholipidic membrane of Giant Unilamellar Vesicles versus hydrophilic or
hydrophobic molecules (in that case the laser spots were set on both sides of
the membrane). Theoretical descriptions are proposed together with a
discus-sion about Fluorescence Correlation Spectroscopy based, alternative
methods.


title:
Electronic Transport Properties of the Ising Quantum Hall Ferromagnet in
  a Si Quantum Well

abstract:
  Magnetotransport properties are investigated for a high mobility Si two
dimensional electron systems in the vicinity of a Landau level crossing point.
At low temperatures, the resistance peak having a strong anisotropy shows large
hysteresis which is attributed to Ising quantum Hall ferromagnetism. The peak
is split into two peaks in the paramagnetic regime. A mean field calculation
for the peak positions indicates that electron scattering is strong when the
pseudospin is partially polarized. We also study the current-voltage
characteristics which exhibit a wide voltage plateau.


title: Polycylcic Aromatic Hydrocarbons (PAH's) in dense cloud chemistry

abstract:
  Virtually all detailed gas-phase models of the chemistry of dense
interstellar clouds exclude polycyclic aromatic hydrocarbons (PAH's). This
omission is unfortunate because from the few studies that have been done on the
subject, it is known that the inclusion of PAH's can affect the gas-phase
chemistry strongly. We have added PAH's to our network to determine the role
they play in the chemistry of cold dense cores. In the models presented here,
we include radiative attachment to form PAH-, mutual neutralization between PAH
anions and small positively-charged ions, and photodetachment. We also test the
sensitivity of our results to changes in the size and abundance of the PAH's.
Our results confirm that the inclusion of PAH's changes many of the calculated
abundances of smaller species considerably. In TMC-1, the general agreement
with observations is significantly improved contrary to L134N. This may
indicate a difference in PAH properties between the two regions. With the
inclusion of PAH's in dense cloud chemistry, high-metal elemental abundances
give a satisfactory agreement with observations. As a result, we do not need to
decrease the observed elemental abundances of all metals and we do not need to
vary the elemental C/O ratio in order to produce large abundances of carbon
species in TMC-1 (CP).


title:
Phase coherence in an ensemble of uncoupled limit-cycle oscillators
  receiving common Poisson impulses

abstract:
  An ensemble of uncoupled limit-cycle oscillators receiving common Poisson
impulses shows a range of non-trivial behavior, from synchronization,
desynchronization, to clustering. The group behavior that arises in the
ensemble can be predicted from the phase response of a single oscillator to a
given impulsive perturbation. We present a theory based on phase reduction of a
jump stochastic process describing a Poisson-driven limit-cycle oscillator, and
verify the results through numerical simula- tions and electric circuit
experiments. We also give a geometrical interpretation of the synchronizing
mechanism, a perturbative expansion to the stationary phase distribution, and
the diffusion limit of our jump stochastic model.


title: Molecular kinetic analysis of a finite-time Carnot cycle

abstract:
  We study the efficiency at the maximal power $\eta_\mathrm{max}$ of a
finite-time Carnot cycle of a weakly interacting gas which we can reagard as a
nearly ideal gas. In several systems interacting with the hot and cold
reservoirs of the temperatures $T_\mathrm{h}$ and $T_\mathrm{c}$, respectively,
it is known that $\eta_\mathrm{max}=1-\sqrt{T_\mathrm{c}/T_\mathrm{h}}$ which
is often called the Curzon-Ahlborn (CA) efficiency $\eta_\mathrm{CA}$. For the
first time numerical experiments to verify the validity of $\eta_\mathrm{CA}$
are performed by means of molecular dynamics simulations and reveal that our
$\eta_\mathrm{max}$ does not always agree with $\eta_\mathrm{CA}$, but
approaches $\eta_\mathrm{CA}$ in the limit of $T_\mathrm{c} \to T_\mathrm{h}$.
Our molecular kinetic analysis explains the above facts theoretically by using
only elementary arithmetic.


title:
Fiber products of elliptic surfaces with section and associated Kummer
  fibrations

abstract:
  We investigate Calabi--Yau three folds which are small resolutions of fiber
products of elliptic surfaces with section admitting reduced fibers. We start
by the classification of all fibers that can appear on such varieties. Then, we
find formulas to compute the Hodge numbers of obtained three folds in terms of
the types of singular fibers of the elliptic surfaces. Next we study Kummer
fibrations associated to these fiber products.


title: Asymptotically optimal quantization schemes for Gaussian processes

abstract:
  We describe quantization designs which lead to asymptotically and order
optimal functional quantizers. Regular variation of the eigenvalues of the
covariance operator plays a crucial role to achieve these rates. For the
development of a constructive quantization scheme we rely on the knowledge of
the eigenvectors of the covariance operator in order to transform the problem
into a finite dimensional quantization problem of normal distributions.
Furthermore we derive a high-resolution formula for the $L^2$-quantization
errors of Riemann-Liouville processes.


title:
Exact Solutions for a Rotational Flow of Generalized Second Grade Fluids
  Through a Circular Cylinder

abstract:
  In this note the velocity field and the associated tangential stress
corresponding to the rotational flows of a generalized second grade fluid
within an infinite circular cylinder are determined by means of the Laplace and
Hankel transforms. At time t=0 the fluid is at rest and the motion is produced
by the rotation of the cylinder, around its axis, with the angular velocity
$\Omega.t$. The velocity field and the adequate shear stress are presented
under integral and series forms in terms of the generalized G-functions.
Furthermore, they are presented as a sum between the Newtonian solutions and
the adequate non-Newtonian contributions. The corresponding solutions for the
ordinary second grade fluid and Newtonian fluid are obtained as particular
cases of our solutions for $\beta = 1$, respectively $\alpha = 0$ and $\beta =
1$.


title: Correspondences between modular Calabi--Yau fiber products

abstract:
  We describe two ways to construct finite rational morphisms between fiber
products of rational elliptic surfaces with section and some Calabi--Yau
manifolds. We use them to construct correspondences between such fiber products
that admit at most five singular fibers and rigid Calabi--Yau threefolds.


title:
Homogeneous studies of transiting extrasolar planets. I. Light curve
  analyses

abstract:
  I present an homogeneous analysis of the transit light curves of 14
well-observed transiting extrasolar planets. The light curves are modelled
using JKTEBOP, random errors are measured using Monte Carlo simulations, and
the effects of correlated noise are included using a residual-permutation
algorithm. The importance of stellar limb darkening (LD) on the light curve
solutions and parameter uncertainties is investigated using five different LD
laws. The linear LD law cannot adequately fit the HST photometry of HD 209458,
but the other four laws give very similar results to each other. In most cases
fixing the LD coefficients at theoretical values does not bias the results, but
DOES cause the error estimates to be too small. The available theoretical LD
coefficients clearly disagree with empirical values measured from the HST light
curves of HD 209458; LD must be included as fitted parameters when analysing
high-quality light curves. In most cases the results of my analysis agree with
the values found by other authors, but the uncertainties I find are up to 3
times larger. Despite this, the analyses of sets of independent light curves
for both HD 189733 and HD 209458 do not agree with each other. This discrepancy
is worst for the ratio of the radii (6.7 and 3.7 sigma), which depends
primarily on the depth of the transit. It is therefore not due to the analysis
method but is present in the light curves. These underlying systematic errors
cannot be detected from the reduced data alone. Using my results and the
stellar spectroscopic orbits, I confirm the correlation between the surface
gravities of transiting extrasolar planets and their orbital periods.
[abridged]


title: Dynamical Casimir Effect for Two Oscillating Mirrors in 3-D

abstract:
  The generation of photons in a three dimensional rectangular cavity with two
moving boundaries is studied by using the Multiple Scale Analysis (MSA). It is
shown that number of photons are enhanced for the cavity whose walls oscillate
symmetrically with respect to the center of the cavity. The non-stationary
Casimir effect is also discussed for the cavity which oscillates as a whole.


title: Polarization effects in non-relativistic $ep$ scattering

abstract:
  The cross section which addresses the spin-flip transitions of a proton
(antiproton) interacting with a polarized non-relativistic electron or positron
is calculated analytically. In the case of attraction, this cross section is
greatly enhanced for sufficiently small relative velocities as compared to the
result obtained in the Born approximation. However, it is still very small, so
that the beam polarization time turns out to be enormously large for the
parameters of $e^{\pm}$ beams available now. This practically rules out a use
of such beams to polarize stored antiprotons or protons.


title: Architecture for Integrated Mems Resonators Quality Factor Measurement

abstract:
  In this paper, an architecture designed for electrical measurement of the
quality factor of MEMS resonators is proposed. An estimation of the measurement
performance is made using PSPICE simulations taking into account the
component's non-idealities. An error on the measured Q value of only several
percent is achievable, at a small integration cost, for sufficiently high
quality factor values (Q > 100).


title:
Optimization of Cricket-inspired, Biomimetic Artificial Hair Sensors for
  Flow Sensing

abstract:
  High density arrays of artificial hair sensors, biomimicking the extremely
sensitive mechanoreceptive filiform hairs found on cerci of crickets have been
fabricated successfully. We assess the sensitivity of these artificial sensors
and present a scheme for further optimization addressing the deteriorating
effects of stress in the structures. We show that, by removing a portion of
chromium electrodes close to the torsional beams, the upward lift at the edges
of the membrane due to the stress, will decrease hence increase the
sensitivity.


title: Stochastic calculus for uncoupled continuous-time random walks

abstract:
  The continuous-time random walk (CTRW) is a pure-jump stochastic process with
several applications in physics, but also in insurance, finance and economics.
A definition is given for a class of stochastic integrals driven by a CTRW,
that includes the Ito and Stratonovich cases. An uncoupled CTRW with zero-mean
jumps is a martingale. It is proved that, as a consequence of the martingale
transform theorem, if the CTRW is a martingale, the Ito integral is a
martingale too. It is shown how the definition of the stochastic integrals can
be used to easily compute them by Monte Carlo simulation. The relations between
a CTRW, its quadratic variation, its Stratonovich integral and its Ito integral
are highlighted by numerical calculations when the jumps in space of the CTRW
have a symmetric Levy alpha-stable distribution and its waiting times have a
one-parameter Mittag-Leffler distribution. Remarkably these distributions have
fat tails and an unbounded quadratic variation. In the diffusive limit of
vanishing scale parameters, the probability density of this kind of CTRW
satisfies the space-time fractional diffusion equation (FDE) or more in general
the fractional Fokker-Planck equation, that generalize the standard diffusion
equation solved by the probability density of the Wiener process, and thus
provides a phenomenologic model of anomalous diffusion. We also provide an
analytic expression for the quadratic variation of the stochastic process
described by the FDE, and check it by Monte Carlo.


title: An algorithmic implementation of the Pi function based on a new sieve

abstract:
  In this paper we propose an algorithm that correctly discards a set of
numbers (from a previously defined sieve) with an interval of integers.
Leopoldo's Theorem states that the remaining integer numbers will generate and
count the complete list of primes of absolute value greater than 3 in the
interval of interest. This algorithm avoids the problem of generating large
lists of numbers, and can be used to compute (even in parallel) the prime
counting function $\pi(h)$.


title:
Lattices and Periodic Geodesics in Pseudoriemannian 2-step Nilpotent Lie
  Groups

abstract:
  We give a basic treatment of lattices $\Gamma$ in these groups. Certain tori
$T_F$ and $T_B$ provide the model fiber and the base for a submersion of
$\Gamma\backslash N$. This submersion may not be pseudoriemannian in the usual
sense, because the tori may be degenerate. We then begin the study of periodic
geodesics in these compact nilmanifolds, obtaining a complete calculation of
the period spectrum of certain flat spaces.


title:
Polyakov soldering and second order frames : the role of the Cartan
  connection

abstract:
  The so-called "soldering" procedure performed by A.M. Polyakov in [1] for a
SL(2,R)-gauge theory is geometrically explained in terms of a Cartan connection
on second order frames of the projective space RP^1. The relationship between a
Cartan connection and the usual (Ehresmann) connection on a principal bundle
allows to gain an appropriate insight into the derivation of the genuine "
diffeomorphisms out of gauge transformations" given by Polyakov himself.


title: Wide-field Fourier transform spectral imaging

abstract:
  We report experimental results of parallel measurement of spectral components
of the light. The temporal fluctuations of an optical field mixed with a
separate reference are recorded with a high throughput complementary metal
oxide semi-conductor camera (1 Megapixel at 2 kHz framerate). A numerical
Fourier transform of the time-domain recording enables wide-field coherent
spectral imaging. Qualitative comparisons with frequency-domain wide-field
laser Doppler imaging are provided.


title:
The quasi-periodic Bose-Hubbard model and localization in
  one-dimensional cold atomic gases

abstract:
  We compute the phase diagram of the one-dimensional Bose-Hubbard model with a
quasi-periodic potential by means of the density-matrix renormalization group
technique. This model describes the physics of cold atoms loaded in an optical
lattice in the presence of a superlattice potential whose wave length is
incommensurate with the main lattice wave length. After discussing the
conditions under which the model can be realized experimentally, the study of
the density vs. the chemical potential curves for a non-trapped system unveils
the existence of gapped phases at incommensurate densities interpreted as
incommensurate charge-density wave phases. Furthermore, a localization
transition is known to occur above a critical value of the potential depth V_2
in the case of free and hard-core bosons. We extend these results to soft-core
bosons for which the phase diagrams at fixed densities display new features
compared with the phase diagrams known for random box distribution disorder. In
particular, a direct transition from the superfluid phase to the Mott
insulating phase is found at finite V_2. Evidence for reentrances of the
superfluid phase upon increasing interactions is presented. We finally comment
on different ways to probe the emergent quantum phases and most importantly,
the existence of a critical value for the localization transition. The later
feature can be investigated by looking at the expansion of the cloud after
releasing the trap.


title:
Dynamic light diffusion, Anderson localization and lasing in disordered
  inverted opals: 3D ab-initio Maxwell-Bloch computation

abstract:
  We report on 3D time-domain parallel simulations of Anderson localization of
light in inverted disordered opals displaying a complete photonic band-gap. We
investigate dynamic diffusion processes induced by femtosecond laser
excitations, calculate the diffusion constant and the decay-time distribution
versus the strength of the disorder. We report evidence of the transition from
delocalized Bloch oscillations to strongly localized resonances in
self-starting laser processes.


title:
Universal intermittent properties of particle trajectories in highly
  turbulent flows

abstract:
  We present a collection of eight data sets, from state-of-the-art experiments
and numerical simulations on turbulent velocity statistics along particle
trajectories obtained in different flows with Reynolds numbers in the range
$R_\lambda \in [120:740]$. Lagrangian structure functions from all data sets
are found to collapse onto each other on a wide range of time lags, revealing a
universal statistics, and calling for a unified theoretical description.
Parisi-Frisch Multifractal theory, suitable extended to the dissipative scales
and to the Lagrangian domain, is found to capture intermittency of velocity
statistics over the whole three decades of temporal scales here investigated.


title:
Fractional Langevin Equation: Over-Damped, Under-Damped and Critical
  Behaviors

abstract:
  The dynamical phase diagram of the fractional Langevin equation is
investigated for harmonically bound particle. It is shown that critical
exponents mark dynamical transitions in the behavior of the system. Four
different critical exponents are found. (i) $\alpha_c=0.402\pm 0.002$ marks a
transition to a non-monotonic under-damped phase, (ii) $\alpha_R=0.441...$
marks a transition to a resonance phase when an external oscillating field
drives the system, (iii) $\alpha_{\chi_1}=0.527...$ and (iv)
$\alpha_{\chi_2}=0.707...$ marks transition to a double peak phase of the
"loss" when such an oscillating field present. As a physical explanation we
present a cage effect, where the medium induces an elastic type of friction.
Phase diagrams describing over-damped, under-damped regimes, motion and
resonances, show behaviors different from normal.


title: The empirical upper limit for mass loss of cool main sequence stars

abstract:
  The knowledge of mass loss rates due to thermal winds in cool dwarfs is of
crucial importance for modeling evolution of physical parameters of main
sequence single and binary stars. Very few, sometimes contradictory,
measurements of such mass loss rates exist up to now. We present a new,
independent method of measuring an amount of mass lost by a star during its
past life. It is based on the comparison of the present mass distribution of
solar type stars in an open cluster with the calculated distribution under an
assumption that stars with masses lower than M(lim) have lost an amount of mass
equal to DeltaM. The actual value of DeltaM or its upper limit is found from
the best fit. Analysis of four clusters: Pleiades, NGC 6996, Hyades and
Praesepe gave upper limits for DeltaM in three of them and the inconclusive
result for Pleiades. The most restrictive limit was obtained for Praesepe
indicating that the average mass loss rate of cool dwarfs in this cluster was
lower than 6x10^{-11} M(sun)/yr. With more accurate mass determinations of the
solar type members of selected open clusters, including those of spectral type
K, the method will provide more stringent limits for mass loss of cool dwarfs.


title: Excitation of Low-Frequency QPOs in Black Hole Accretion Flows

abstract:
  We present the results of global three dimensional magneto-hydrodynamic
simulations of black hole accretion flows. We focus on the dependence of
numerical results on the gas temperature Tout supplied from the outer region.
General relativistic effects are taken into account using the pseudo-Newtonian
potential. We ignore the radiative cooling of the accreting gas. The initial
state is a torus whose density maximum is at 35rs or 50rs from the gravitating
center, where rs is the Schwarzschild radius. The torus is initially threaded
by a weak azimuthal magnetic field. We found that mass accretion rate and the
mass outflow rate strongly depend on the temperature of the initial torus. The
ratio of the average Maxwell stress generated by the magneto-rotational
instability (MRI) to gas pressure is alpha ~0.05 in the hot torus and alpha ~
0.01 in the cool torus. In the cool model, a constant angular momentum inner
torus is formed around 4-8rs. This inner torus deforms itself from a circle to
a crescent quasi-periodically. During this deformation, the mass accretion
rate, the magnetic energy and the Maxwell stress increase. As the magnetic
energy is released, the inner torus returns to a circular shape and starts the
next cycle.
  Power spectral density (PSD) of the time variation of the mass accretion rate
in the cool model has a low frequency peak around 10Hz when we assumed a 10
solar mass black hole. The PSD of the hot model is flat in 1-30Hz. The slope of
the PSD in the cool model is steeper than that in the hot model in 30-100Hz.
The mass outflow rate in the low temperature model also shows quasi-periodic
oscillation. Intermittent outflows are created in both models. The outflow
speed is $0.01c - 0.05c$.


title: Boundary instability of a two-dimensional plasma

abstract:
  It was shown previously that the current-carrying state of a Field Effect
Transistor with asymmetric source and drain boundary conditions may become
unstable against spontaneous generation of plasma waves [1]. By extending the
analysis to the two-dimensional case we find that the dominant instability
modes correspond to waves propagating in the direction perpendicular to the
current and localized near the boundaries. This new type of instability should
result in plasma turbulency with a broad frequency spectrum. More generally, it
is shown that a similar instability might exist, when a strong enough current
goes through a single boundary between the gated and ungated regions.


title: BRST operators for W algebras

abstract:
  The study of quantum Lie algebras motivates a use of non-canonical ghosts and
anti-ghosts for non-linear algebras, like W-algebras. This leads, for the W_3
and W_3^(2) algebras, to the BRST operator having the conventional cubic form.


title: Saturation of nuclear matter in effective field theory

abstract:
  The two- and three-nucleon interaction derived in chiral effective field
theory at next-to-next-to-leading order is used to obtain the binding energy of
nuclear matter. Saturation is found at a binding energy per particle E/A =
-16.2 \pm 0.3 MeV and a Fermi momentum k_F = 1.30 \pm 0.03 fm^{-1}, where the
uncertainty is due to the cut-off dependence of the two-nucleon interaction.
The sensitivity of these values to the three-nucleon force is also studied.