title: A new characterization of Baire class 1 functions

abstract:
  We give a new characterization of the Baire class 1 functions (defined on an
ultrametric space) by proving that they are exactly the pointwise limits of
sequences of full functions (which are particularly simple Lipschitz
functions). Moreover we highlight the link between the two classical
stratifications of the Borel functions by showing that the Baire class
functions of some level are exactly those obtained as uniform limits of
sequences of Delta functions (of a corresponding level).


title: Effect of strain on the electronic structure of La0.7Ca0.3MnO3

abstract:
  The effect of substrate strain on the electronic valence band structure of
La0.7Ca0.3MnO3 thin films has been investigated. For this purpose
La0.7Ca0.3MnO3 thin films have been simultaneously grown on SrTiO3 and LaAlO3
substrates using pulsed laser deposition technique. These samples were
characterized by x-ray diffraction, x-ray reflectivity, core level x-ray
photoelectron spectroscopy, and scanning electron microscopy measurements. Our
experiments confirmed that all these samples have same chemical composition but
different strain configuration. The electronic structure of these samples is
probed through valence band spectroscopy measurements on Indus-1 synchrotron
x-ray source. We observe that strain has large effect on the valence band
electronic structure of La0.7Ca0.3MnO3. The results are explained on the basis
of strain induced orbital occupancy and change in the crystal field splitting
due to Mn-O bond length.


title: Nanowire waveguide made from extremely anisotropic metamaterials

abstract:
  Exact solutions are obtained for all the modes of wave propagation along an
anisotropic cylindrical waveguide. Closed-form expressions for the energy flow
on the waveguide are also derived. For extremely anisotropic waveguide where
the transverse permittivity is negative while the longitudinal permittivity is
positive, only transverse magnetic (TM) and hybrid modes will propagate on the
waveguide. At any given frequency the waveguide supports an infinite number of
eigenmodes. Among the TM modes, at most only one mode is forward wave. The rest
of them are backward waves which can have very large effective index. At a
critical radius, the waveguide supports degenerate forward- and backward-wave
modes with zero group velocity. These waveguides can be used as phase shifters
and filters, and as optical buffers to slow down and trap light.


title: J/psi production at RHIC-PHENIX

abstract:
  The J/psi is considered to be among the most important probes for the
deconfined quark gluon plasma (QGP) created by relativistic heavy ion
collisions. While the J/psi is thought to dissociate in the QGP by Debye color
screening, there are competing effects from cold nuclear matter (CNM),
feed-downs from excited charmonia (chi_c and psi') and bottom quarks, and
regeneration from uncorrelated charm quarks. Measurements that can provide
information to disentangle these effects are presented in this paper.


title: On the structure of Clifford quantum cellular automata

abstract:
  We study reversible quantum cellular automata with the restriction that these
are also Clifford operations. This means that tensor products of Pauli
operators (or discrete Weyl operators) are mapped to tensor products of Pauli
operators. Therefore Clifford quantum cellular automata are induced by
symplectic cellular automata in phase space. We characterize these symplectic
cellular automata and find that all possible local rules must be, up to some
global shift, reflection invariant with respect to the origin. In the one
dimensional case we also find that every uniquely determined and
translationally invariant stabilizer state can be prepared from a product state
by a single Clifford cellular automaton timestep, thereby characterizing these
class of stabilizer states, and we show that all 1D Clifford quantum cellular
automata are generated by a few elementary operations. We also show that the
correspondence between translationally invariant stabilizer states and
translationally invariant Clifford operations holds for periodic boundary
conditions.


title: Non-photonic electron-hadron correlations at STAR

abstract:
  We present STAR's measurements of azimuthal correlations between non-photonic
electrons and charged hadrons in p+p, Cu+Cu and Au+Au collisions at 200 GeV. In
p+p collisions, from the non-photonic e-h correlation we have extracted the
relative B meson semi-leptonic decay contributions to non-photonic electrons up
to electron $p_t \sim 9$ GeV/$c$. In central Cu+Cu and Au+Au collisions where a
dense medium is created, we find that the e-h correlation on the away side of
the trigger non-photonic electron has been modified in comparison with the
expectation from PYTHIA simulations.


title:
Monte Carlo simulation of particle interactions at high dynamic range:
  Advancing beyond the Googol

abstract:
  We present a method which extends Monte Carlo studies to situations that
require a large dynamic range in particle number. The underlying idea is that,
in order to calculate the collisional evolution of a system, some particle
interactions are more important than others and require more resolution, while
the behavior of the less important, usually of smaller mass, particles can be
considered collectively. In this approximation groups of identical particles,
sharing the same mass and structural parameters, operate as one unit. The
amount of grouping is determined by the zoom factor -- a free parameter that
determines on which particles the computational effort is focused. Two methods
for choosing the zoom factors are discussed: the `equal mass method,' in which
the groups trace the mass density of the distribution, and the `distribution
method,' which additionally follows fluctuations in the distribution. Both
methods achieve excellent correspondence with analytic solutions to the
Smoluchowski coagulation equation. The grouping method is furthermore applied
to simulations involving runaway kernels, where the particle interaction rate
is a strong function of particle mass, and to situations that include
catastrophic fragmentation. For the runaway simulations previous predictions
for the decrease of the runaway timescale with the initial number of particles
${\cal N}$ are reconfirmed, extending ${\cal N}$ to $10^{160}$. Astrophysical
applications include modeling of dust coagulation, planetesimal accretion, and
the dynamical evolution of stars in large globular clusters. The proposed
method is a powerful tool to compute the evolution of any system where the
particles interact through discrete events, with the particle properties
characterized by structural parameters.


title: Worldlines as Wilson Lines

abstract:
  Gravitational theories do not admit gauge invariant local operators. We study
the limits under which there exists a quasi-local description for a class of
non-local gravitational observables where a sum over worldlines plays the role
of the Wilson line for gauge theory observables. We study non-local corrections
to the local description and circumstances where these corrections become
large. We find that these operators are quasi-local in flat space and AdS, but
fail to be quasi-local in de Sitter space.


title: Dependence Structure Estimation via Copula

abstract:
  Dependence strucuture estimation is one of the important problems in machine
learning domain and has many applications in different scientific areas. In
this paper, a theoretical framework for such estimation based on copula and
copula entropy -- the probabilistic theory of representation and measurement of
statistical dependence, is proposed. Graphical models are considered as a
special case of the copula framework. A method of the framework for estimating
maximum spanning copula is proposed. Due to copula, the method is irrelevant to
the properties of individual variables, insensitive to outlier and able to deal
with non-Gaussianity. Experiments on both simulated data and real dataset
demonstrated the effectiveness of the proposed method.


title:
Glueball nature of the sigma/f_0(600) from pi-pi and gamma-gamma
  scatterings

abstract:
  We estimate the I=0 scalar meson sigma/f_0(600) parameters from pi-pi and
gamma-gamma scattering data below 700 MeV using an improved analytic K-matrix
model. A fit of the hadronic data gives a complex pole mass M_sigma= 422-i290
MeV, while simultaneous best fits of the gamma-gamma to pi+pi-, pi0pi0 data
give a direct width of (0.13+-0.05)keV, a rescattering component of
(2.7+-0.4)keV and a total (direct+rescattering) width of (3.9+-0.6)keV.
"Running" these results to the physical real axis, the small "direct"
gamma-gamma and the large hadronic widths at the "on-shell" mass are compatible
with QCD spectral sum rules (QSSR) and some low-energy theorems (LET)
expectations for an unmixed lowest mass glueball/gluonium sigma_B of a mass
around 1 GeV and a large OZI-violation decay into pi-pi.


title: Magnetic moments of long isotopic chains

abstract:
  Dipole magnetic moments of several long isotopic chains are analyzed within
the self-consistent Finite Fermi System theory based on the Generalized Energy
Density Functional method with exact account for the pairing and quasi-particle
continuum. New data for nuclei far from the beta-stability valley are included
in the analysis. For a number of semi-magic isotopes of the tin and lead chains
a good description of the data is obtained, with accuracy of 0.1 - 0.2 mu_N. A
chain of non-magic isotopes of copper is also analyzed in detail. It is found
that the systematic analysis of magnetic moments of this long chain yields rich
information on the evolution of the nuclear structure of the Cu isotopes. In
particular, it may give a signal of deformation for the ground state of some
nuclei in the chain.


title:
Non-unitary representations, Baum-Connes morphism and unconditional
  completions

abstract:
  We show that the Baum-Connes morphism twisted by a non-unitary
representation, defined in [GA08], is an isomorphism for a large class of
groups satisfying the Baum-Connes conjecture. Such class contains all the real
semi-simple Lie groups, all hyperbolic groups and many infinite discret groups
having Kazhdan's property (T). We define a tensorisation by a non-unitary
finite dimensional representation on the left handside of the Baum-Connes
morphism and we show that its analogue in K-theory must be defined on the
K-theory of the twisted group algebras introduced in [GA07b].


title: On the Capacity Bounds of Undirected Networks

abstract:
  In this work we improve on the bounds presented by Li&Li for network coding
gain in the undirected case. A tightened bound for the undirected multicast
problem with three terminals is derived. An interesting result shows that with
fractional routing, routing throughput can achieve at least 75% of the coding
throughput. A tighter bound for the general multicast problem with any number
of terminals shows that coding gain is strictly less than 2. Our derived bound
depends on the number of terminals in the multicast network and approaches 2
for arbitrarily large number of terminals.


title: Temperature of systems out of thermodynamic equilibrium

abstract:
  Two phenomenological approaches are currently used in the study of the
vitreous state. One is based on the concept of fictive temperature introduced
by Tool [Jour. Research Nat. Bur. Standards 34, 199 (1945)] and recently
revisited by Nieuwenhuizen [Phys. Rev. Lett. 80, 5580 (1998)]. The other is
based on the thermodynamics of irreversible processes initiated by De Donder at
the beginning of the last century [L'Affinit\'e (Gauthier-Villars, Paris,
1927)] and recently used by M\"oller and co-workers for a thorough study of the
glass transition [J. Chem. Phys. 125, 094505 (2006)]. This latter approach
leads to the possibility of describing the glass transition by means of the
freezing-in of one or more order parameters connected to the internal
structural degrees of freedom involved in the vitrification process. In this
paper, the equivalence of the two preceding approaches is demonstrated, not
only for glasses, but in a very general way for any system undergoing an
irreversible transformation. This equivalence allows the definition of an
effective temperature for all systems departed from equilibrium generating a
positive amount of entropy. In fact, the initial fictive temperature concept of
Tool leads to the generalization of the notion of temperature for systems out
of thermodynamic equilibrium, for which glasses are just particular cases.


title:
Image recognition with an adiabatic quantum computer I. Mapping to
  quadratic unconstrained binary optimization

abstract:
  Many artificial intelligence (AI) problems naturally map to NP-hard
optimization problems. This has the interesting consequence that enabling
human-level capability in machines often requires systems that can handle
formally intractable problems. This issue can sometimes (but possibly not
always) be resolved by building special-purpose heuristic algorithms, tailored
to the problem in question. Because of the continued difficulties in automating
certain tasks that are natural for humans, there remains a strong motivation
for AI researchers to investigate and apply new algorithms and techniques to
hard AI problems. Recently a novel class of relevant algorithms that require
quantum mechanical hardware have been proposed. These algorithms, referred to
as quantum adiabatic algorithms, represent a new approach to designing both
complete and heuristic solvers for NP-hard optimization problems. In this work
we describe how to formulate image recognition, which is a canonical NP-hard AI
problem, as a Quadratic Unconstrained Binary Optimization (QUBO) problem. The
QUBO format corresponds to the input format required for D-Wave superconducting
adiabatic quantum computing (AQC) processors.


title:
Magnetic field induced rotation of the d-vector in the spin triplet
  superconductor Sr$_2$RuO$_4$

abstract:
  In zero magnetic field the superconductor Sr$_2$RuO$_4$ is believed to have a
chiral spin triplet pairing state in which the gap function d-vector is aligned
along the crystal c-axis. Using a phenomenological but orbital specific
description of the spin dependent electron-electron attraction and a realistic
quantitative account of the electronic structure in the normal state we analyze
the orientation of the spin triplet Cooper pair d-vector in response to an
external c-axis magnetic field. We show that for suitable values of the model
parameters a c-axis field of only 20 mT is able to cause a reorientation phase
transition of the d-vector from along $c$ to the $a-b$ plane, in agreement with
recent experiments.


title:
Black Holes on Thin 3-branes of Codimension-2 and their Extension into
  the Bulk

abstract:
  We discuss black hole solutions in six-dimensional gravity with a
Gauss-Bonnet term in the bulk and an induced gravity term on a thin 3-brane of
codimension-2. We show that these black holes can be localized on the brane,
and they can further be extended into the bulk by a warp function. These
solutions have regular horizons and no other curvature singularities appear
apart from the string-like ones. The projection of the Gauss-Bonnet term on the
brane imposes a constraint relation which requires the presence of matter in
the extra dimensions.


title: New (and Old) Perspectives on Higgs Physics

abstract:
  Old and new ideas regarding Higgs physics are reviewed. We first summarize
the quadratic divergence / hierarchy problem which strongly suggests that the
SM Higgs sector will be supplemented by new physics at high scales. We next
consider means for delaying the hierarchy problem of the SM Higgs sector to
unexpectedly high scales. We then outline the properties of the most ideal
Higgs boson. The main advantages of a supersymmetric solution to the high scale
problems are summarized and the reasons for preferring the next-to-minimal
supersymmetric model over the minimal supersymmetric model in order to achieve
an ideal Higgs are emphasized. This leads us to the strongly motivated scenario
in which there is a Higgs $h$ with SM-like $WW,ZZ$ couplings and $\mh\sim
100\gev$ that decays via $h\to aa$ with $m_a<2m_b$, where $m_a>2m_\tau$ is
preferred, implying $a\to \tau^+ \tau^-$. The means for detecting an $h\to
aa\to 4\tau$ signal are then discussed. Some final cautionary and concluding
remarks are given.


title: Theory of quasi-one dimensional imbalanced Fermi gases

abstract:
  We present a theory for a lattice array of weakly coupled one-dimensional
ultracold attractive Fermi gases (1D `tubes') with spin imbalance, where strong
intratube quantum fluctuations invalidate mean field theory. We first construct
an effective field theory, which treats spin-charge mixing exactly, based on
the Bethe ansatz solution of the 1D single tube problem. We show that the 1D
Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state is a two-component Luttinger
liquid, and its elementary excitations are fractional states carrying both
charge and spin. We analyze the instability of the 1D FFLO state against
inter-tube tunneling by renormalization group analysis, and find that it flows
into either a polarized Fermi liquid or a FFLO superfluid, depending on the
magnitude of interaction strength and spin imbalance. We obtain the phase
diagram of the quasi-1D system and further determine the scaling of the
superfluid transition temperature with intertube coupling.


title: Matrix Cubes Parametrized by Eigenvalues

abstract:
  An elimination problem in semidefinite programming is solved by means of
tensor algebra. It concerns families of matrix cube problems whose constraints
are the minimum and maximum eigenvalue function on an affine space of symmetric
matrices. An LMI representation is given for the convex set of all feasible
instances, and its boundary is studied from the perspective of algebraic
geometry. This generalizes the earlier work [12] with Parrilo on k-ellipses and
k-ellipsoids.


title:
Disorder-Induced Stabilization of the Pseudogap in Strongly Correlated
  Systems

abstract:
  The interplay of strong interaction and strong disorder, as contained in the
Anderson-Hubbard model, is addressed using two non-perturbative numerical
methods: the Lanczos algorithm in the grand canonical ensemble at zero
temperature and Quantum Monte Carlo. We find distinctive evidence for a
zero-energy anomaly which is robust upon variation of doping, disorder and
interaction strength. Its similarities to, and differences from, pseudogap
formation in other contexts, including perturbative treatments of interactions
and disorder, classical theories of localized charges, and in the clean Hubbard
model, are discussed.


title: Stabbing simplices by points and flats

abstract:
  The following result was proved by Barany in 1982: For every d >= 1 there
exists c_d > 0 such that for every n-point set S in R^d there is a point p in
R^d contained in at least c_d n^{d+1} - O(n^d) of the simplices spanned by S.
  We investigate the largest possible value of c_d. It was known that c_d <=
1/(2^d(d+1)!) (this estimate actually holds for every point set S). We
construct sets showing that c_d <= (d+1)^{-(d+1)}, and we conjecture this
estimate to be tight. The best known lower bound, due to Wagner, is c_d >=
gamma_d := (d^2+1)/((d+1)!(d+1)^{d+1}); in his method, p can be chosen as any
centerpoint of S. We construct n-point sets with a centerpoint that is
contained in no more than gamma_d n^{d+1}+O(n^d) simplices spanned by S, thus
showing that the approach using an arbitrary centerpoint cannot be further
improved.
  We also prove that for every n-point set S in R^d there exists a (d-2)-flat
that stabs at least c_{d,d-2} n^3 - O(n^2) of the triangles spanned by S, with
c_{d,d-2}>=(1/24)(1- 1/(2d-1)^2). To this end, we establish an equipartition
result of independent interest (generalizing planar results of Buck and Buck
and of Ceder): Every mass distribution in R^d can be divided into 4d-2 equal
parts by 2d-1 hyperplanes intersecting in a common (d-2)-flat.


title:
Improved Laboratory Transition Probabilities for Er II and Applications
  to the Erbium Abundances of the Sun and Five r-Process Rich, Metal-Poor Stars

abstract:
  Recent radiative lifetime measurements accurate to +/- 5% (Stockett et al.
2007, J. Phys. B 40, 4529) using laser-induced fluorescence (LIF) on 8
even-parity and 62 odd-parity levels of Er II have been combined with new
branching fractions measured using a Fourier transform spectrometer (FTS) to
determine transition probabilities for 418 lines of Er II. This work moves Er
II onto the growing list of rare earth spectra with extensive and accurate
modern transition probability measurements using LIF plus FTS data. This
improved laboratory data set has been used to determine a new solar
photospheric Er abundance, log epsilon = 0.96 +/- 0.03 (sigma = 0.06 from 8
lines), a value in excellent agreement with the recommended meteoric abundance,
log epsilon = 0.95 +/- 0.03. Revised Er abundances have also been derived for
the r-process-rich metal-poor giant stars CS 22892-052, BD+17 3248, HD 221170,
HD 115444, and CS 31082-001. For these five stars the average Er/Eu abundance
ratio, <log epsilon (Er/Eu)> = 0.42, is in very good agreement with the
solar-system r-process ratio. This study has further strengthened the finding
that r-process nucleosynthesis in the early Galaxy which enriched these
metal-poor stars yielded a very similar pattern to the r-process which enriched
later stars including the Sun.


title:
Free Distance Bounds for Protograph-Based Regular LDPC Convolutional
  Codes

abstract:
  In this paper asymptotic methods are used to form lower bounds on the free
distance to constraint length ratio of several ensembles of regular,
asymptotically good, protograph-based LDPC convolutional codes. In particular,
we show that the free distance to constraint length ratio of the regular LDPC
convolutional codes exceeds that of the minimum distance to block length ratio
of the corresponding LDPC block codes.


title: The warm absorber in NGC 5548: The lean years

abstract:
  We study the variability of the warm absorber and the gas responsible for the
emission lines in the Seyfert 1 galaxy NGC 5548, in order to constrain the
location and physical properties of these components. Using X-ray spectra taken
with the \textit{Chandra}$-$LETGS in 2002 and 2005, we study variability in the
ionic column densities and line intensities. We find a lower \ion{O}{vii}
forbidden emission line flux in 2005, while the Fe K$\alpha$ line flux stays
constant. The warm absorber is less ionized in 2005, allowing us to constrain
its location to within 7 pc of the central source. Using both the observed
variability and the limit on the FWHM of the \ion{O}{vii} f line, we have
constrained the location of the narrow line region to a distance of 1 pc from
the central source. The apparent lack of variability of the Fe K$ \alpha$ line
flux does not allow for a unique explanation.


title: One-Way Quantum Computing in the Optical Frequency Comb

abstract:
  One-way quantum computing allows any quantum algorithm to be implemented
easily using just measurements. The difficult part is creating the universal
resource, a cluster state, on which the measurements are made. We propose a
radically new approach: a scalable method that uses a single, multimode optical
parametric oscillator (OPO). The method is very efficient and generates a
continuous-variable cluster state, universal for quantum computation, with
quantum information encoded in the quadratures of the optical frequency comb of
the OPO.


title:
Josephson Current and Noise at a Superconductor-Quantum Spin Hall
  Insulator-Superconductor Junction

abstract:
  We study junctions between superconductors mediated by the edge states of a
quantum spin Hall insulator. We show that such junctions exhibit a fractional
Josephson effect, in which the current phase relation has a 4\pi, rather than a
2\pi periodicity. This effect is a consequence of the conservation of fermion
parity - the number of electrons modulo 2 - in a superconducting junction, and
is closely related to the Z_2 topological structure of the quantum spin Hall
insulator. Inelastic processes, which violate the conservation of fermion
parity, lead to telegraph noise in the equilibrium supercurrent. We predict
that the low frequency noise due these processes diverges exponentially with
temperature T as T -> 0. Possible experiments on HgCdTe quantum wells will be
discussed.


title: Gauge/gravity duality and the interplay of various fractional branes

abstract:
  We consider different types of fractional branes on a Z_2 orbifold of the
conifold and analyze in detail the corresponding gauge/gravity duality. The
gauge theory possesses a rich and varied dynamics, both in the UV and in the
IR. We find the dual supergravity solution which contains both untwisted and
twisted 3-form fluxes, related to what are known as deformation and N=2
fractional branes respectively. We analyze the resulting RG flow from the
supergravity perspective, by developing an algorithm to easily extract it. We
find hints of a generalization of the familiar cascade of Seiberg dualities due
to a non-trivial interplay between the different types of fractional branes. We
finally consider the IR behavior in several limits, where the dominant
effective dynamics is either confining, in a Coulomb phase or runaway, and
discuss the resolution of singularities in the dual geometric background.


title: Flavoured Soft Leptogenesis

abstract:
  We study the impact of flavour in ``soft leptogenesis'' (leptogenesis induced
by soft supersymmetry breaking terms). We address the question of how flavour
effects can affect the region of parameters in which successful soft
leptogenesis induced by CP violation in the right-handed sneutrino mixing is
possible. We find that for decays which occur in the intermediate to strong
washout regimes for all flavours, the produced total $B-L$ asymmetry can be up
to a factor ${\cal O}(30)$ larger than the one predicted with flavour effects
being neglected. This enhancement, permits slightly larger values of the
required lepton violating soft bilinear term.


title: The Peculiar Globular Cluster System of the S0 Galaxy NGC 7457

abstract:
  We present HST photometry and Keck spectroscopy of globular clusters (GCs) in
the nearby S0 galaxy NGC 7457. The V-I color-magnitude diagram of GCs lacks the
clear bimodality present in most early-type galaxies; there may be a
significant population of intermediate-color objects. Of 13
spectroscopically-observed GCs, two are unusually metal-rich and feature bright
[O III] emission lines. We conclude that one probably hosts a planetary nebula
and the other a supernova remnant. Such emission line objects should be more
common in an intermediate-age stellar population than in an old one. We
therefore suggest that, in addition to the typical old metal-rich and old
metal-poor GC subpopulations, there may be a third subpopulation of
intermediate age. Such a subpopulation may have been formed ~2-3 Gyr ago, in
the same star-forming event that dominates the stellar population of the center
of the galaxy.


abstract:
  The ever-expanding depth and quality of photometric and spectroscopic
observations of stellar populations increase the need for theoretical models in
regions of age-composition parameter space that are largely unexplored at
present. Stellar evolution models that employ the most advanced physics and
cover a wide range of compositions are needed to extract the most information
from current observations of both resolved and unresolved stellar populations.
The Dartmouth Stellar Evolution Database is a collection of stellar evolution
tracks and isochrones that spans a range of [Fe/H] from -2.5 to +0.5,
[alpha/Fe] from -0.2 to +0.8 (for [Fe/H] <=0) or +0.2 (for [Fe/H] >0), and
initial He mass fractions from Y=0.245 to 0.40. Stellar evolution tracks were
computed for masses between 0.1 and 4 Msun, allowing isochrones to be generated
for ages as young as 250 Myr. For the range in masses where the core He flash
occurs, separate He-burning tracks were computed starting from the zero age
horizontal branch. The tracks and isochrones have been transformed to the
observational plane in a variety of photometric systems including standard
UBV(RI)c, Stromgren uvby, SDSS ugriz, 2MASS JHKs, and HST ACS-WFC and WFPC2.
The Dartmouth Stellar Evolution Database is accessible through a website at
http://stellar.dartmouth.edu/~models/ where all tracks, isochrones, and
additional files can be downloaded.


title: Damped Lyman Alpha Systems in Galaxy Formation Simulations

abstract:
  We investigate the population of z=3 damped Lyman alpha absorbers (DLAs) in a
recent series of high resolution galaxy formation simulations. The simulations
are of interest because they form at z=0 some of the most realistic disk
galaxies to date. No free parameters are available in our study: these have
been fixed by physical and z=0 observational constraints, and thus our study
provides a genuine consistency test. The precise role of DLAs in galaxy
formation remains in debate, but they provide a number of strong constraints on
the nature of our simulated bound systems at z=3 because of their coupled
information on neutral H I densities, kinematics, metallicity and estimates of
star formation activity.
  Our results, without any parameter-tuning, closely match the observed
incidence rate and column density distributions of DLAs. Our simulations are
the first to reproduce the distribution of metallicities (with a median of
Z_{DLA} = Z_{solar}/20) without invoking observationally unsupported mechanisms
such as dust biasing. This is especially encouraging given that these
simulations have previously been shown to have a realistic 0<z<2 stellar
mass-metallicity relation. Additionally, we see a strong positive correlation
between sightline metallicity and low-ion velocity width, the normalization and
slope of which comes close to matching recent observational results. However,
we somewhat underestimate the number of observed high velocity width systems;
the severity of this disagreement is comparable to other recent DLA focused
studies. By z=0 the majority of the z=3 neutral gas forming the DLAs has been
converted into stars, in agreement with rough physical expectations.
  [Abridged]


title:
The Transit Light Curve Project. IX. Evidence for a Smaller Radius of
  the Exoplanet XO-3b

abstract:
  We present photometry of 13 transits of XO-3b, a massive transiting planet on
an eccentric orbit. Previous data led to two inconsistent estimates of the
planetary radius. Our data strongly favor the smaller radius, with increased
precision: R_p = 1.217 +/- 0.073 R_Jup. A conflict remains between the mean
stellar density determined from the light curve, and the stellar surface
gravity determined from the shapes of spectral lines. We argue the light curve
should take precedence, and revise the system parameters accordingly. The
planetary radius is about 1 sigma larger than the theoretical radius for a
hydrogen-helium planet of the given mass and insolation. To help in planning
future observations, we provide refined transit and occultation ephemerides.


title:
The stochastic gravitational-wave background from massive black hole
  binary systems: implications for observations with Pulsar Timing Arrays

abstract:
  Massive black hole binary systems, with masses in the range ~10^4-10^10
\msun, are among the primary sources of gravitational waves in the frequency
window ~10^-9 Hz - 0.1 Hz. Pulsar Timing Arrays (PTAs) and the Laser
Interferometer Space Antenna (LISA) are the observational means by which we
will be able to observe gravitational radiation from these systems. We carry
out a systematic study of the generation of the stochastic gravitational-wave
background from the cosmic population of massive black hole binaries. We
consider a wide variety of assembly scenarios and we estimate the range of
signal strength in the frequency band accessible to PTAs. We show that, taking
into account the uncertainties surrounding the actual key model parameters, the
amplitude lies in the interval h_c(f = 10^-8 Hz)~5x10^-16 - 8x10^-15. The most
optimistic predictions place the signal level at a factor of ~3 below the
current sensitivity of Pulsar Timing Arrays, but within the detection range of
the complete Parkes PTA for a wide variety of models, and of the future
Square-Kilometer-Array PTA for all the models considered here. We also show
that at frequencies >10^-8 Hz the frequency dependency of the generated
background follows a power-law significantly steeper than f^-2/3, that has been
considered so far. Finally we show that LISA observations of individual
resolvable massive black hole binaries are complementary and orthogonal to PTA
observations of a stochastic background from the whole population in the
Universe. In fact, the detection of gravitational radiation in both frequency
windows will enable us to fully characterise the cosmic history of massive
black holes.


title:
Angular momentum-Large-scale structure alignments in LCDM models and the
  SDSS

abstract:
  We study the alignments between the angular momentum of individual objects
and the large-scale structure in cosmological numerical simulations and real
data from the Sloan Digital Sky Survey, Data Release 6. To this end we measure
anisotropies in the two point cross-correlation function around simulated halos
and observed galaxies, studying separately the 1- and 2-halo regimes. The
alignment of the angular momentum of dark-matter haloes in LCDM simulations is
found to be dependent on scale and halo mass. At large distances (2-halo
regime), the spins of high mass haloes are preferentially oriented in the
direction perpendicular to the distribution of matter; lower mass systems show
a weaker trend that may even reverse to show an angular momentum in the plane
of the matter distribution. In the 1-halo term regime, the angular momentum is
aligned in the direction perpendicular to the matter distribution; the effect
is stronger than for the 1-halo term and increases for higher mass systems.
  On the observational side, we focus our study on galaxies in the Sloan
Digital Sky Survey, Data Release 6 (SDSS-DR6) with elongated apparent shapes,
and study alignments with respect to the major semi-axis. We find an excess of
structure in the direction of the major semi-axis for all samples; the red
sample shows the highest alignment (2.7+-0.08%) and indicates that the angular
momentum of flattened spheroidals tends to be perpendicular to the large-scale
structure. (Abridged)


title: The influence of halo assembly on galaxies and galaxy groups

abstract:
  In this paper, we study the variations of group galaxy properties according
to the assembly history in SDSS-DR6 selected groups. Using mock SDSS group
catalogues, we find two suitable indicators of group formation time: i) the
isolation of the group, defined as the distance to the nearest neighbor in
terms of its virial radius, and ii) the concentration, measured as the group
inner density calculated using the fifth nearest bright galaxy to the group
centre. Groups within narrow ranges of mass in the mock catalogue show
increasing group age with isolation and concentration. However, in the
observational data the stellar age, as indicated by the spectral type, only
shows a correlation with concentration. We study groups of similar mass and
different assembly history, finding important differences in their galaxy
population. Particularly, in high mass SDSS groups, the number of members,
mass-to-light ratios, red galaxy fractions and the magnitude difference between
the brightest and second brightest group galaxies, show different trends as a
function of isolation and concentration, even when it is expected that the
latter two quantities correlate with group age. Conversely, low mass SDSS
groups appear to be less sensitive to their assembly history. The correlations
detected in the SDSS are not consistent with the trends measured in the mock
catalogues. However, discrepancies can be explained in terms of the
disagreement found in the age-isolation trends, suggesting that the model might
be overestimating the effects of environment.We discuss how the modeling of the
cold gas in satellite galaxies could be responsible for this problem. These
results can be used to improve our understanding of the evolution of galaxies
in high-density environments.


title: Geometrical Properties of Feynman Path Integrals

abstract:
  This model is one of the possible geometrical interpretations of Quantum
Mechanics where found to every image Path correspondence the geodesic
trajectory of classical test particles in the random geometry of the stochastic
fields background. We are finding to the imagined Feynman Path a classical
model of test particles as geodesic trajectory in the curved space of Projected
Hilbert space on Bloch's sphere.


title: On an area property of the sum cotA+cotB+cotC in a triangle

abstract:
  Given a triangle ABC, a new triangle A'B'C' can be formed as follows: Draw
the perpendicular to the line AB at the pointA; then the perpendicular to the
line BC at B, and lastly the perpendicular to the line CA at C.the two
triangles ABC and A'B'C' are always similar. In Postulate1 we prove that the
ratio E'/E is equal to (cotA+cotB+cotC)^2, which is the main result in this
work.Here E' and E stand for the areas of the triangles A'B'C' and ABC
respectively. In Postulate 2, we show that the above ratio has minimum value 3,
which is attained when ABC and A'B'C' are equilateral triangles.In Postulate 3,
we show that if we consider only those pairs of triangles (ABC,A'B'C'), with
both ABC and A'B'C' being right triangles, then the minimum value of the above
ratio of areas, is 4.


title: Reconnection in Marginally Collisionless Accretion Disk Coronae

abstract:
  We point out that a conventional construction placed upon observations of
accreting black holes, in which their nonthermal X-ray spectra are produced by
inverse comptonization in a coronal plasma, suggests that the plasma is
marginally collisionless. Recent developments in plasma physics indicate that
fast reconnection takes place only in collisionless plasmas. As has recently
been suggested for the Sun's corona, such marginal states may result from a
combination of energy balance and the requirements of fast magnetic
reconnection.


title: A Survey for Fast Transients in the Fornax Cluster of Galaxies

abstract:
  The luminosity gap between novae (M_R < -10) and supernovae (M_R > -14) is
well known since the pioneering research of Zwicky and Hubble. Nearby galaxy
clusters and concentrations offer an excellent opportunity to search for
explosions brighter than classical novae and fainter than supernovae. Here, we
present the results of a B-band survey of 23 member galaxies of the Fornax
cluster, performed at the Las Campanas 2.5-m Irene duPont telescope.
Observations with a cadence of 32 minutes discovered no genuine fast transient
to a limiting absolute magnitude of M_B=-9.3 mag. We provide a detailed
assessment of the transient detection efficiency and the resulting upper limits
on the event rate as function of peak magnitude. Further, we discuss the
discoveries of five previously unknown foreground variables which we identified
as two flare stars, two W Uma type eclipsing binaries and a candidate delta
Scuti/SX Phe star.


title:
Galaxy Zoo : Morphologies derived from visual inspection of galaxies
  from the Sloan Digital Sky Survey

abstract:
  In order to understand the formation and subsequent evolution of galaxies one
must first distinguish between the two main morphological classes of massive
systems: spirals and early-type systems. This paper introduces a project,
Galaxy Zoo, which provides visual morphological classifications for nearly one
million galaxies, extracted from the Sloan Digital Sky Survey (SDSS). This
achievement was made possible by inviting the general public to visually
inspect and classify these galaxies via the internet. The project has obtained
more than 40,000,000 individual classifications made by ~100,000 participants.
We discuss the motivation and strategy for this project, and detail how the
classifications were performed and processed. We find that Galaxy Zoo results
are consistent with those for subsets of SDSS galaxies classified by
professional astronomers, thus demonstrating that our data provides a robust
morphological catalogue. Obtaining morphologies by direct visual inspection
avoids introducing biases associated with proxies for morphology such as
colour, concentration or structual parameters. In addition, this catalogue can
be used to directly compare SDSS morphologies with older data sets. The
colour--magnitude diagrams for each morphological class are shown, and we
illustrate how these distributions differ from those inferred using colour
alone as a proxy for morphology.


title: Phantom-like behaviour in a brane-world model with curvature effects

abstract:
  Recent observational evidence seems to allow the possibility that our
universe may currently be under a dark energy effect of a phantom nature. A
suitable effective phantom fluid behaviour can emerge in brane cosmology; In
particular, within the normal non self-accelerating DGP branch, without any
exotic matter and due to curvature effects from induced gravity. The
phantom-like behaviour is based in defining an effective energy density that
grows as the brane expands. This effective description breaks down at some
point in the past when the effective energy density becomes negative and the
effective equation of state parameter blows up. In this paper we investigate if
the phantom-like regime can be enlarged by the inclusion of a Gauss-Bonnet (GB)
term into the bulk. The motivation is that such a GB component would model
additional curvature effects on the brane setting. More precisely, our aim is
to determine if the GB term, dominating and modifying the early behaviour of
the brane universe, may eventually extend the regime of validity of the phantom
mimicry on the brane. However, we show that the opposite occurs: the GB effect
seems instead to induce a breakdown of the phantom-like behaviour at an even
smaller redshift.


title:
Scaling Properties of Critical Phase Change Conditions in Ge2Sb2Te5
  Nanopillars

abstract:
  We have measured the critical phase change conditions induced by electrical
pulses in Ge2Sb2Te5 nanopillar phase change memory devices by constructing a
comprehensive resistance map as a function of pulse parameters (width,
amplitude and trailing edge). Our measurements reveal that the cooling scheme
and the details of the contact geometry play the dominant role in determining
the final phase composition of the device. A three-dimensional finite element
model of the electro-thermal physics not only provides good insights into the
underlying physical mechanisms of the switching dynamics but also
quantitatively accounts for the observed scaling behaviour.


title: Highlights and Perspectives of the JLab Spin Physics Program

abstract:
  Nucleon spin structure has been an active and exciting subject of interest
for the last three decades. Recent precision spin-structure data from Jefferson
Lab have significantly advanced our knowledge of nucleon structure in the
valence quark (high-x) region and improved our understanding of higher-twist
effects, spin sum rules and quark-hadron duality. First, results of spin sum
rules and polarizabilities in the low to intermediate Q^2 region are presented.
Comparison with theoretical calculations are discussed. Surprising
disagreements of Chiral Perturbation Theory calculations with experimental
results on the generalized spin polarizability, \delta_{LT}, were found. Then,
precision measurements of the spin asymmetry in the high-x region are
presented. They provide crucial input for global fits to world data to extract
polarized parton distribution functions. The up and down quark spin
distributions in the nucleon were extracted. The results for \Delta d/d
disagree with the leading-order pQCD prediction assuming hadron helicity
conservation. Results of precision measurements of the g_2 structure function
to study higher-twist effects are presented. The data indicate a significant
higher-twist (twist-3 or higher) effect. The second moment of the spin
structure functions and the twist-3 matrix element d_2 results were extracted.
The high Q^2 result was compared with a Lattice QCD calculation. Results on the
resonance spin-structure functions in the intermediate Q^2 range are presented,
which, in combination with DIS data, enable a detailed study of quark-hadron
duality in spin-structure functions. Finally, an experiment to study neutron
transversity and transverse spin asymmetries is discussed. A future plan with
the 12 GeV energy upgrade at JLab is briefly outlined.


title: Entropy Enhancement and Black Hole Microstates

abstract:
  We study fluctuating two-charge supertubes in three-charge geometries. We
show that the entropy of these supertubes is determined by their
locally-defined effective charges, which differ from their asymptotic charges
by terms proportional to the background magnetic fields. When supertubes are
placed in deep, scaling microstate solutions, these effective charges can
become very large, leading to a much larger entropy than one naively would
expect. Since fluctuating supertubes source smooth geometries in certain
duality frames, we propose that such an entropy enhancement mechanism might
lead to a black-hole like entropy coming entirely from configurations that are
smooth and horizonless in the regime of parameters where the classical black
hole exists.


title: Curvature perturbation spectrum from false vacuum inflation

abstract:
  In the inflationary cosmology it occurs frequently that the inflaton field is
trapped in a local, transient minimum with non-zero vacuum energy. The
difficulty regarding the curvature perturbation produced during such a stage is
that classically the inflaton does not move so that the comoving hypersurfaces
are not well defined at linear order in the scalar field perturbation. In this
paper, assuming a mechanism of trapping which resembles a high temperature
correction to the potential, we explicitly calculate for the first time the
resulting power spectrum of the curvature perturbation by evaluating the
quantum two-point correlation function directly. The spectrum is steeply blue
with the spectral index n_R = 4.


title:
Generalized Degrees of Freedom of the Symmetric Gaussian $K$ User
  Interference Channel

abstract:
  We characterize the generalized degrees of freedom of the $K$ user symmetric
Gaussian interference channel where all desired links have the same
signal-to-noise ratio (SNR) and all undesired links carrying interference have
the same interference-to-noise ratio, ${INR}={SNR}^\alpha$. We find that the
number of generalized degrees of freedom per user, $d(\alpha)$, does not depend
on the number of users, so that the characterization is identical to the 2 user
interference channel with the exception of a singularity at $\alpha=1$ where
$d(1)=\frac{1}{K}$. The achievable schemes use multilevel coding with a nested
lattice structure that opens the possibility that the sum of interfering
signals can be decoded at a receiver even though the messages carried by the
interfering signals are not decodable.


title: Infinite sequences in the framework of classical logic

abstract:
  Infinite sequences are considered in the framework of classical logic from a
new point of view.


title:
The Mid-Infrared Colors of the ISM and Extended Sources at the Galactic
  Center

abstract:
  A mid-infrared (3.6-8 um) survey of the Galactic Center has been carried out
with the IRAC instrument on the Spitzer Space Telescope. This survey covers the
central 2x1.4 degree (~280x200 pc) of the Galaxy. At 3.6 and 4.5 um the
emission is dominated by stellar sources, the fainter ones merging into an
unresolved background. At 5.8 and 8 um the stellar sources are fainter, and
large-scale diffuse emission from the ISM of the Galaxy's central molecular
zone becomes prominent. The survey reveals that the 8 to 5.8 um color of the
ISM emission is highly uniform across the surveyed region. This uniform color
is consistent with a flat extinction law and emission from polycyclic aromatic
hydrocarbons (PAHs). Models indicate that this broadband color should not be
expected to change if the incident radiation field heating the dust and PAHs is
<10^4 times that of the solar neighborhood. The few regions with unusually red
emission are areas where the PAHs are underabundant and the radiation field is
locally strong enough to heat large dust grains to produce significant 8 um
emission. These red regions include compact H II regions, Sgr B1, and wider
regions around the Arches and Quintuplet Clusters. In these regions the
radiation field is >10^4 times that of the solar neighborhood. Other regions of
very red emission indicate cases where thick dust clouds obscure deeply
embedded objects or very early stages of star formation.


title:
Fulde-Ferrell-Larkin-Ovchinnikov state in disordered s-wave
  superconductors

abstract:
  The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state is a superconducting state
stabilized by a large Zeeman splitting between up- and down-spin electrons in a
singlet superconductor. In the absence of disorder, the superconducting order
parameter has a periodic spatial structure, with periodicity determined by the
Zeeman splitting. Using the Bogoliubov-de Gennes (BdG) approach, we investigate
the spatial profiles of the order parameters of FFLO states in a
two-dimensional s-wave superconductors with nonmagnetic impurities. The FFLO
state is found to survive under moderate disorder strength, and the order
parameter structure remains approximately periodic. The actual structure of the
order parameter depends on not only the Zeeman field, but also the disorder
strength and in particular the specific disorder configuration.


title: The dilepton probe in heavy-ion collisions

abstract:
  Dileptons provide direct observables of the electromagnetic current-current
correlator in the hot and/or dense medium formed in heavy-ion collisions. In
this article an overview is given about the status of the theoretical
understanding of the dilepton phenomenology in heavy-ion collisions from
studies of the in-medium properties of hadrons and partons within many-body
theory and about connections to fundamental questions concerning the chiral
phase transition.


title: Recent QCD Studies at the Tevatron

abstract:
  Since the beginning of Run II at the Fermilab Tevatron, the QCD physics
groups of the CDF and D0 experiments have worked to reach unprecedented levels
of precision for many QCD observables. Thanks to the large dataset - over 3
fb^-1 of integrated luminosity recorded by each experiment - many important new
measurements have recently been made public and will be summarized in this
paper.


title:
High mass star formation in the IRAS 17233-3606 region: a new nearby and
  bright hot core in the southern sky

abstract:
  We present molecular line observations of the massive star forming region
IRAS 17233-3606 aimed at studying the molecular core associated with the
source. The observations were made using the Atacama Pathfinder Experiment
telescope in the CO (3-2) and HCO^+ (4-3) transitions, and in the CH_3OH
(6_K-5_K), (7_K-6_K) and CH_3CN (16_K-15_K) bands. For the CO(3-2) and HCO^+
(4-3) transitions, we obtained maps with a size of 70''\times 70''. The typical
angular resolution of the data is ~18''. Our observations reveal an
exceptionally rich molecular spectrum, a signpost of hot core activity.
Comparisons with two other prominent southern hot cores were made through
observations in the same frequency setups. We also detected a bipolar outflow
in CO (3-2) and HCO^+ (4-3) lines. Modelling reveals a hot core of size ~3''
and a temperature of 150 K in the IRAS17233-3606 region. The parameters of the
molecular outflow are derived through the analysis of the CO (3-2) emission,
and are typical of outflows driven by high-mass young stellar objects.


title: The Successful Prediction of the Extrasolar Planet HD 74156 d

abstract:
  Most of the first-discovered extrasolar multi-planet systems were found to
lie close to dynamically unstable configurations. However a few observed
multi-planet systems (e.g. HD 74156) did not show this trait. Those systems
could share this property if they contain an additional planet in between those
that are known. Previous investigations identified the properties of
hypothetical planets that would place these systems near instability. The
hypothetical planet in HD 74156 was expected to have a mass about equal to that
of Saturn, a semi-major axis between 0.9 and 1.4 AU, and an eccentricity less
than 0.2. HD 74156 d, a planet with a mass of 1.3 Saturn masses at 1.04 AU with
an eccentricity of 0.25, was recently announced. We have reanalyzed all
published data on this system in order to place tighter constraints on the
properties of the new planet. We find two possible orbits for this planet, one
close to that already identified and another (with a slightly better fit to the
data) at ~0.89 AU. We also review the current status of other planet
predictions, discuss the observed single planet systems, and suggest other
systems which may contain planets in between those that are already known. The
confirmation of the existence of HD 74156 d suggests that planet formation is
an efficient process, and planetary systems should typically contain many
planets.


title: On the spectra of a Cantor measure

abstract:
  We analyze all orthonormal bases of exponentials on the Cantor set defined by
Jorgensen and Pedersen in J. Anal. Math. 75,1998, pp 185-228. A complete
characterization for all maximal sets of orthogonal exponentials is obtained by
establishing a one-to-one correspondence with the spectral labelings of the
infinite binary tree. With the help of this characterization we obtain a
sufficient condition for a spectral labeling to generate a spectrum (an
orthonormal basis). This result not only provides us an easy and efficient way
to construct various of new spectra for the Cantor measure but also extends
many previous results in the literature. In fact, most known examples of
orthonormal bases of exponentials correspond to spectral labelings satisfying
this sufficient condition. We also obtain two new conditions for a labeling
tree to generate a spectrum when other digits (digits not necessarily in $\{0,
1, 2, 3\}$) are used in the base 4 expansion of integers and when bad branches
are allowed in the spectral labeling. These new conditions yield new examples
of spectra and in particular lead to a surprizing example which shows that a
maximal set of orthogonal exponentials is not necessarily an orthonormal basis.


title:
When correlations matter - response of dynamical networks to small
  perturbations

abstract:
  We systematically study and compare damage spreading for random Boolean and
threshold networks under small external perturbations (damage), a problem which
is relevant to many biological networks. We identify a new characteristic
connectivity $K_s$, at which the average number of damaged nodes after a large
number of dynamical updates is independent of the total number of nodes $N$. We
estimate the critical connectivity for finite $N$ and show that it
systematically deviates from the annealed approximation. Extending the approach
followed in a previous study, we present new results indicating that internal
dynamical correlations tend to increase not only the probability for small, but
also for very large damage events, leading to a broad, fat-tailed distribution
of damage sizes. These findings indicate that the descriptive and predictive
value of averaged order parameters for finite size networks - even for
biologically highly relevant sizes up to several thousand nodes - is limited.


title:
Coherent states engineering with linear optics: Possible and impossible
  tasks

abstract:
  The general transformation of the product of coherent states
$\prod_{i=1}^N|\alpha_i>$ to the output state $\prod_{i=1}^M|\beta_i>$ ($N=M$
or $N\neq M$), which is realizable with linear optical circuit, is
characterized with a linear map from the vector
$(\alpha^{\ast}_1,...,\alpha^{\ast}_N)$ to
$(\beta^{\ast}_1,...,\beta^{\ast}_M)$. A correspondence between the
transformations of a product of coherent states and those of a single photon
state is established with such linear maps. It is convenient to apply this
linear transformation method to design any linear optical scheme working with
coherent states. The examples include message encoding and quantum database
searching. The limitation of manipulating entangled coherent states with linear
optics is also discussed.


title: Fractional Action-Like Variational Problems

abstract:
  Fractional action-like variational problems have recently gained importance
in studying dynamics of nonconservative systems. In this note we address
multi-dimensional fractional action-like problems of the calculus of
variations.


title: Lattice Study of Planar Equivalence: The Quark Condensate

abstract:
  We study quenched SU(N) gauge theories with fermions in the two-index
symmetric, antisymmetric and the adjoint representations. Our main motivation
is to check whether at large number of colours those theories become
non-perturbatively equivalent. We prove the equivalence assuming that the
charge-conjugation symmetry is not broken in pure Yang-Mills theory. We then
carry out a quenched lattice simulation of the quark condensate in the
symmetric, antisymmetric and the adjoint representations for SU(2), SU(3),
SU(4), SU(6) and SU(8). We show that the data support the equivalence and
discuss the size of subleading corrections.


title: Spin polarization of the $\nu=5/2$ quantum Hall state

abstract:
  We report on results of numerical studies of the spin polarization of the
half filled second Landau level, which corresponds to the fractional quantum
Hall state at filling factor $\nu=5/2$. Our studies are performed using both
exact diagonalization and Density Matrix Renormalization Group (DMRG) on the
sphere. We find that for the Coulomb interaction the exact finite-system ground
state is fully polarized, for shifts corresponding to both the Moore-Read
Pfaffian state and its particle-hole conjugate (anti-Pfaffian). This result is
found to be robust against small variations of the interaction. The low-energy
excitation spectrum is consistent with spin-wave excitations of a
fully-magnetized ferromagnet.


title: Criticality in diluted ferromagnet

abstract:
  We perform a detailed study of the critical behavior of the mean field
diluted Ising ferromagnet by analytical and numerical tools. We obtain
self-averaging for the magnetization and write down an expansion for the free
energy close to the critical line. The scaling of the magnetization is also
rigorously obtained and compared with extensive Monte Carlo simulations. We
explain the transition from an ergodic region to a non trivial phase by
commutativity breaking of the infinite volume limit and a suitable vanishing
field. We find full agreement among theory, simulations and previous results.


title: $\Upsilon$ production in p+p and Au+Au collisions in STAR

abstract:
  The study of quarkonium production in relativistic heavy ion collisions
provides insight into the properties of the produced medium. The lattice
studies show a sequential suppression of quarkonia states when compared to
normal nuclear matter; which further affirms that a full spectroscopy including
bottomonium can provide us a better thermometer for the matter produced under
extreme conditions in relativistic heavy ion collisions. With the completion of
the STAR Electromagnetic Calorimeter and with the increased luminosity provided
by RHIC in Run 6 and 7, the study of $\Upsilon$ production via the di-electron
channel becomes possible. We present the results on $\Upsilon$ measurements in
p+p collisions (from Run 6) along with the first results from Au+Au collisions
(in Run 7) at $\sqrt{s_{\rm{NN}}} = 200$ GeV from the STAR experiment.


title:
Extension theorems for the Fourier transform associated with
  non-degenerate quadratic surfaces in vector spaces over finite fields

abstract:
  We study the restriction of the Fourier transform to quadratic surfaces in
vector spaces over finite fields. In two dimensions, we obtain the sharp result
by considering the sums of arbitrary two elements in the subset of quadratic
surfaces on two dimensional vector spaces over finite fields. For higher
dimensions, we estimate the decay of the Fourier transform of the
characteristic functions on quadratic surfaces so that we obtain the
Tomas-Stein exponent. Using incidence theorems, we also study the extension
theorems in the restricted settings to sizes of sets in quadratic surfaces.
Estimates for Gauss and Kloosterman sums and their variants play an important
role.


title:
New Bound States of Top-anti-Top Quarks and T-balls Production at
  Colliders (Tevatron, LHC, etc.)

abstract:
  The present talk is based on the assumption that New Bound States (NBSs) of
top-anti-top quarks (named T-balls) exist in the Standard Model (SM): a) there
exists the scalar 1S - bound state of 6t+6\bar t - the bound state of 6
top-quarks with their 6 anti-top-quarks; b) the forces which bind these
top-quarks are very strong and almost completely compensate the mass of the 12
top-anti-top-quarks forming this bound state; c) such strong forces are
produced by the interactions of top-quarks via the virtual exchange of the
scalar Higgs bosons having the large value of the top-quark Yukawa coupling
constant g_t\simeq 1. Theory also predicts the existence of the NBS 6t + 5\bar
t, which is a color triplet and a fermion similar to the t'-quark of the fourth
generation. We have also considered "b-replaced" NBSs: n_b b + (6t + 6\bar t -
n_b t) and n'_b b + (6t + 5\bar t - n'_b t), etc. We have estimated the masses
of the lightest "b-replaced" NBS: M_{NBS}\simeq (300 - 400) GeV, and discussed
the larger masses of the NBSs. We have developed a theory of the scalar
T-ball's condensate, and predicted the existence of the three SM phases,
calculating the top-quark Yukawa coupling constant at the border of two phases
(with T-ball's condensate and without it) equal to: g_t \approx 1. The
searching for the Higgs boson H and T-balls at the Tevatron and LHC is
discussed.


title: Integrability of the Gauged Linear Sigma Model for AdS_5xS^5

abstract:
  Recently, a gauged linear sigma model was proposed by Berkovits and Vafa
which can be used to describe the AdS_5xS^5 superstring at finite and zero
radius. In this paper we show that the model is classically integrable by
constructing its first non-local conserved charge and a superspace Lax
"quartet". Quantum conservation of the non-local charge follows easily from
superspace rules.


title:
A Geometric Proof to Cantor's Theorem and an Irrationality Measure for
  Some Cantor's Series

abstract:
  Generalizing a geometric idea due to J. Sondow, we give a geometric proof for
the Cantor's Theorem. Moreover, it is given an irrationality measure for some
Cantor series.


title: The absolute frequency of the 87Sr optical clock transition

abstract:
  The absolute frequency of the 1S0-3P0 clock transition of 87Sr has been
measured to be 429 228 004 229 873.65 (37) Hz using lattice-confined atoms,
where the fractional uncertainty of 8.6x10-16 represents one of the most
accurate measurements of an atomic transition frequency to date. After a
detailed study of systematic effects, which reduced the total systematic
uncertainty of the Sr lattice clock to 1.5x10-16, the clock frequency is
measured against a hydrogen maser which is simultaneously calibrated to the US
primary frequency standard, the NIST Cs fountain clock, NIST-F1. The comparison
is made possible using a femtosecond laser based optical frequency comb to
phase coherently connect the optical and microwave spectral regions and by a
3.5 km fiber transfer scheme to compare the remotely located clock signals.


title:
Global solutions to the three-dimensional full compressible
  magnetohydrodynamic flows

abstract:
  The equations of the three-dimensional viscous, compressible, and heat
conducting magnetohydrodynamic flows are considered in a bounded domain. The
viscosity coefficients and heat conductivity can depend on the temperature. A
solution to the initial-boundary value problem is constructed through an
approximation scheme and a weak convergence method. The existence of a global
variational weak solution to the three-dimensional full magnetohydrodynamic
equations with large data is established.


title: On the holomorphic closure dimension of real analytic sets

abstract:
  Given a real analytic (or, more generally, semianalytic) set R in the
n-dimensional complex space, there is, for every point p in the closure of R, a
unique smallest complex analytic germ X_p that contains the germ R_p. We call
the complex dimension of X_p the holomorphic closure dimension of R at p. We
show that the holomorphic closure dimension of an irreducible R is constant on
the complement of a closed proper analytic subset of R, and discuss the
relationship between this dimension and the CR dimension of R.


title: Circular Jacobi Ensembles and deformed Verblunsky coefficients

abstract:
  Using the spectral theory of unitary operators and the theory of orthogonal
polynomials on the unit circle, we propose a simple matrix model for the
following circular analogue of the Jacobi ensemble: $$c_{\delta,\beta}^{(n)}
\prod_{1\leq k<l\leq n}|
e^{\ii\theta_k}-e^{\ii\theta_l}|^\beta\prod_{j=1}^{n}(1-e^{-\ii\theta_j})^{\delta}
(1-e^{\ii\theta_j})^{\overline{\delta}} $$ with $\Re \delta > -1/2$. If $e$ is
a cyclic vector for a unitary $n\times n$ matrix $U$, the spectral measure of
the pair $(U,e)$ is well parameterized by its Verblunsky coefficients
$(\alpha_0, ..., \alpha_{n-1})$. We introduce here a deformation $(\gamma_0,
>..., \gamma_{n-1})$ of these coefficients so that the associated Hessenberg
matrix (called GGT) can be decomposed into a product $r(\gamma_0)...
r(\gamma_{n-1})$ of elementary reflections parameterized by these coefficients.
If $\gamma_0, ..., \gamma_{n-1}$ are independent random variables with some
remarkable distributions, then the eigenvalues of the GGT matrix follow the
circular Jacobi distribution above.
  These deformed Verblunsky coefficients also allow to prove that, in the
regime $\delta = \delta(n)$ with $\delta(n)/n \to \dd$, the spectral measure
and the empirical spectral distribution weakly converge to an explicit
nontrivial probability measure supported by an arc of the unit circle. We also
prove the large deviations for the empirical spectral distribution.


title:
Tuning the quantum tunneling and quantum information properties among
  the trion states in coupled quantum dots

abstract:
  Quantum transition and information properties of the Coulomb coupled trion
(electron-electron-hole) in the double quantum dots under the influence of the
time-dependent electric field have been studied. Tuning the Hubbard interaction
strength amongst the states of electron-hole complexes and the parameters of
the ac field, two strikingly different kinds of approximate qubit can be
constructed within the eight trion states. The similarity and difference
between the electron dynamic entanglement and overlapping of the wavefunction
with the Bell state have been elucidated through analyzing these two kinds of
qubit.


title:
Resistivity reduction of boron-doped multi-walled carbon nanotubes
  synthesized from a methanol solution containing a boric acid

abstract:
  Boron-doped multi-walled carbon nanotubes (MWNTs) were synthesized using a
methanol solution of boric acid as a source material. Accurate measurements of
the electrical resistivity of an individual boron-doped MWNT was performed with
a four-point contact, which was fabricated using an electron beam lithography
technique. The doped boron provides conduction carriers, which reduces the
resistivity of the MWNT.


title:
Quark Mixing from Mass Matrix Model with Flavor 2 (\leftrightarrow) 3
  Symmetry

abstract:
  We consider an universal mass matrix model which has a seesaw-invariant
structure with the most general texture based on flavor 2 (\leftrightarrow) 3
symmetry common to all quarks and leptons. The CKM quark mixing matrix of the
model is analyzed. It is shown that the model is consistent with all the
experimental data of quark mixings by tuning free parameters of the model. We
also show that the values of parameters of the present model consistent with
the experimental data are not far from the ones of the mass matrix model with a
vanishing (1,1) element.


title:
Luminosity Function Constraints on the Evolution of Massive Red Galaxies
  Since z~0.9

abstract:
  We measure the evolution of the luminous red galaxy (LRG) luminosity function
in the redshift range 0.1<z<0.9 using samples of galaxies from the Sloan
Digital Sky Survey as well as new spectroscopy of high-redshift massive red
galaxies. Our high-redshift sample of galaxies is largest spectroscopic sample
of massive red galaxies at z~0.9 collected to date and covers 7 square deg,
minimizing the impact of large scale structure on our results. We find that the
LRG population has evolved little beyond the passive fading of its stellar
populations since z~0.9. Based on our luminosity function measurements and
assuming a non-evolving Salpeter stellar initial mass function, we find that
the most massive (L>3L*) red galaxies have grown by less than 50% (at 99%
confidence), since z=0.9, in stark contrast to the factor of 2-4 growth
observed in the L* red galaxy population over the same epoch. We also
investigate the evolution of the average LRG spectrum since z~0.9 and find the
high-redshift composite to be well-described as a passively evolving example of
the composite galaxy observed at low-redshift. From spectral fits to the
composite spectra, we find at most 5% of the stellar mass in massive red
galaxies may have formed within 1Gyr of z=0.9. While L* red galaxies are
clearly assembled at z<1, 3L* galaxies appear to be largely in place and evolve
little beyond the passive evolution of their stellar populations over the last
half of cosmic history.


title: A multivariate generalization of Costa's entropy power inequality

abstract:
  A simple multivariate version of Costa's entropy power inequality is proved.
In particular, it is shown that if independent white Gaussian noise is added to
an arbitrary multivariate signal, the entropy power of the resulting random
variable is a multidimensional concave function of the individual variances of
the components of the signal. As a side result, we also give an expression for
the Hessian matrix of the entropy and entropy power functions with respect to
the variances of the signal components, which is an interesting result in its
own right.


title:
Mirror dark matter and the new DAMA/LIBRA results: A simple explanation
  for a beautiful experiment

abstract:
  Recently, the DAMA/LIBRA experiment has convincingly confirmed the DAMA/NaI
annual modulation signal, experimentally demonstrating the existence of
non-baryonic dark matter in the halo of our galaxy. Meanwhile, in another part
of town, other experiments such as CDMS and XENON10 have not detected any
evidence for dark matter. One promising dark matter candidate which can
reconcile the positive DAMA annual modulation signal with the null results from
the other experiments, is mirror dark matter. We re-analyse the mirror matter
interpretation of the DAMA annual modulation signal utilizing a) the new data
from DAMA/LIBRA, including the measured energy dependence of the annual
modulation signal b) an updated quenching factor which takes into account the
channeling effect in $NaI$ crystals and c) the latest constraints from CDMS/Ge,
CDMS/Si and XENON10 experiments. We show that the simplest possibility of a
$He'$ (and/or $H'$) dominated halo with a small $O'$ component is sufficient to
fully explain all of the dark matter experiments. We also point out that a
certain class of hidden sector dark matter models, although theoretically less
appealing and less constrained, can mimic the success of the mirror dark matter
model and hence are also viable.


title:
Cordes conditions and some alternatives for parabolic equations and
  discontinuous diffusion

abstract:
  The paper considers parabolic equations in non-divergent form with
discontinuous coefficients at higher derivatives. Their investigation is most
complicated because, in general, in the case of discontinuous coefficients, the
uniqueness of a solution for nonlinear parabolic or elliptic equations can
fail, and there is no a priory estimate for partial derivatives of a solution.
In this paper, existence and regularity results are obtained under some Cordes
type restrictions on the coefficients. The results are applied to diffusion
processes.


title: On the Formation of Perseus OB1 at High Galactic Latitudes

abstract:
  The Per OB1 association, which contains the remarkable double cluster h and
chi Per, is unusual in not having a giant molecular cloud in its vicinity. We
show from Hipparcos data that the luminous members of this association exhibits
a bulk motion away from the galactic plane, such that their average velocity
increases with height above the galactic plane. We find HAeBe and T Tauri stars
towards probable remnant molecular clouds associated with Per OB1. These
star-forming regions lie well beyond the location of the luminous member stars
at heights of 280-400 pc above the galactic plane, far higher than that
previously found for embedded clusters. We argue that the observed motion of
the luminous member stars is most naturally explained if many formed from
molecular gas pushed and accelerated outwards by an expanding superbubble
driven presumably by stellar winds and perhaps also supernova explosions. A
large shell of atomic hydrogen gas and dust that lies just beyond the remnant
molecular clouds, believed to be driven by just such a superbubble, may
comprise the swept-up remains of the parental giant molecular cloud from which
this association formed. In support of this picture, we find a week trend for
the younger O star members to lie at higher galactic latitudes than the older
supergiant members. The star-forming regions located at even larger heights
above the galactic plane presumably correspond to more recent episodes of star
formation at or near the periphery of this superbubble.


title:
Numerical solutions of integrodifferential systems by hybrid of general
  block-pulse functions and the second Chebyshev polynomials

abstract:
  By applying hybrid functions of general block-pulse functions and the second
Chebyshev polynomials,integrodifferential systems are converted into a system
of algebraic equations. The approximate solutions of integrodifferential
systems are derived. The numerical examples illustrate that the algorithms are
valid.


title:
Optimal solution of investment problems via linear parabolic equations
  generated by Kalman filter

abstract:
  We consider optimal investment problems for a diffusion market model with
non-observable random drifts that evolve as an Ito's process. Admissible
strategies do not use direct observations of the market parameters, but rather
use historical stock prices. For a non-linear problem with a general
performance criterion, the optimal portfolio strategy is expressed via the
solution of a scalar minimization problem and a linear parabolic equation with
coefficients generated by the Kalman filter.


title: A non-distillability criterion for secret correlations

abstract:
  Within entanglement theory there are criteria which certify that some quantum
states cannot be distilled into pure entanglement. An example is the positive
partial transposition criterion. Here we present, for the first time, the
analogous thing for secret correlations. We introduce a computable criterion
which certifies that a probability distribution between two honest parties and
an eavesdropper cannot be (asymptotically) distilled into a secret key. The
existence of non-distillable correlations with positive secrecy cost, also
known as bound information, is an open question. This criterion may be the key
for finding bound information. However, if it turns out that this criterion
does not detect bound information, then, a very interesting consequence
follows: any distribution with positive secrecy cost can increase the secrecy
content of another distribution. In other words, all correlations with positive
secrecy cost constitute a useful resource.


title: Approximate Equilibria in Games with Few Players

abstract:
  We study the problem of computing approximate Nash equilibria (epsilon-Nash
equilibria) in normal form games, where the number of players is a small
constant. We consider the approach of looking for solutions with constant
support size. It is known from recent work that in the 2-player case, a
1/2-Nash equilibrium can be easily found, but in general one cannot achieve a
smaller value of epsilon than 1/2. In this paper we extend those results to the
k-player case, and find that epsilon = 1-1/k is feasible, but cannot be
improved upon. We show how stronger results for the 2-player case may be used
in order to slightly improve upon the epsilon = 1-1/k obtained in the k-player
case.


title: The Complexity of Coverage

abstract:
  We study the problem of generating a test sequence that achieves maximal
coverage for a reactive system under test. We formulate the problem as a
repeated game between the tester and the system, where the system state space
is partitioned according to some coverage criterion and the objective of the
tester is to maximize the set of partitions (or coverage goals) visited during
the game. We show the complexity of the maximal coverage problem for
non-deterministic systems is PSPACE-complete, but is NP-complete for
deterministic systems. For the special case of non-deterministic systems with a
re-initializing ``reset'' action, which represent running a new test input on a
re-initialized system, we show that the complexity is again co-NP-complete. Our
proof technique for reset games uses randomized testing strategies that
circumvent the exponentially large memory requirement in the deterministic
case.


title: Long heterochromatic paths in heterochromatic triangle free graphs

abstract:
  In this paper, graphs under consideration are always edge-colored. We
consider long heterochromatic paths in heterochromatic triangle free graphs.
Two kinds of such graphs are considered, one is complete graphs with Gallai
colorings, i.e., heterochromatic triangle free complete graphs; the other is
heterochromatic triangle free graphs with $k$-good colorings, i.e., minimum
color degree at least $k$. For the heterochromatic triangle free graphs $K_n$,
we obtain that for every vertex $v\in V(K_n)$, $K_n$ has a heterochromatic
$v$-path of length at least $d^c(v)$; whereas for the heterochromatic triangle
free graphs $G$ we show that if, for any vertex $v\in V(G)$, $d^c(v)\geq k\geq
6$, then $G$ a heterochromatic path of length at least $\frac{3k}{4}$.


title: Topological surface states in three-dimensional magnetic insulators

abstract:
  An electron moving in a magnetically ordered background feels an effective
magnetic field that can be both stronger and more rapidly varying than typical
externally applied fields. One consequence is that insulating magnetic
materials in three dimensions can have topologically nontrivial properties of
the effective band structure. For the simplest case of two bands, these "Hopf
insulators" are characterized by a topological invariant as in quantum Hall
states and Z_2 topological insulators, but instead of a Chern number or parity,
the underlying invariant is the Hopf invariant that classifies maps from the
3-sphere to the 2-sphere. This paper gives an efficient algorithm to compute
whether a given magnetic band structure has nontrivial Hopf invariant, a
double-exchange-like tight-binding model that realizes the nontrivial case, and
a numerical study of the surface states of this model.


title:
Angular Momentum Coupling and Rabi Frequencies for Simple Atomic
  Transitions

abstract:
  The Rabi frequency (coupling strength) of an electric-dipole transition is an
important experimental parameter in laser-cooling and other atomic physics
experiments. Though the relationship between Rabi frequency and atomic
wavefunctions and/or atomic lifetimes is discussed in many references, there is
a need for a concise, self-contained, accessible introduction to such
calculations suitable for use by the typical student of laser cooling
(experimental or theoretical). In this paper, I outline calculations of the
Rabi frequencies for atoms with sub-structure due to orbital, spin and nuclear
angular momentum. I emphasize the physical meaning of the calculations.


title: Vector Bosons in Strong Fields

abstract:
  The Coulomb problem for charged massive vector bosons is known to be
unstable, the boson falls on the Coulomb center. It is shown that when the
charge of the Coulomb center is smeared over a small but finite volume, then
instead of the fall there appears a large series of bound states localized
inside the volume containing the Coulomb charge. It is shown also that the fall
on the Coulomb center is completely suppressed, when the conventional QED
vacuum polarization is taken into account.In gauge theories (SU(2), Standard
Model) the renormalizability of a theory may be insufficient to guarantee an
absence of the wave function collapse. Another interesting feature: the density
of charge of vector bosons can have a ``wrong'' sign.


title: Strategy Improvement for Concurrent Safety Games

abstract:
  We consider concurrent games played on graphs. At every round of the game,
each player simultaneously and independently selects a move; the moves jointly
determine the transition to a successor state. Two basic objectives are the
safety objective: ``stay forever in a set F of states'', and its dual, the
reachability objective, ``reach a set R of states''. We present in this paper a
strategy improvement algorithm for computing the value of a concurrent safety
game, that is, the maximal probability with which player 1 can enforce the
safety objective. The algorithm yields a sequence of player-1 strategies which
ensure probabilities of winning that converge monotonically to the value of the
safety game.
  The significance of the result is twofold. First, while strategy improvement
algorithms were known for Markov decision processes and turn-based games, as
well as for concurrent reachability games, this is the first strategy
improvement algorithm for concurrent safety games. Second, and most
importantly, the improvement algorithm provides a way to approximate the value
of a concurrent safety game from below (the known value-iteration algorithms
approximate the value from above). Thus, when used together with
value-iteration algorithms, or with strategy improvement algorithms for
reachability games, our algorithm leads to the first practical algorithm for
computing converging upper and lower bounds for the value of reachability and
safety games.


title: Intersection numbers from the antisymmetric Gaussian matrix model

abstract:
  The matrix model of topological field theory for the moduli space of p-th
spin curves is extended to the case of the Lie algebra of the orthogonal group.
We derive a new duality relation for the expectation values of characteristic
polynomials in the antisymmetric Gaussian matrix model with an external matrix
source. The intersection numbers for non-orientable surfaces of spin curves
with k marked points are obtained from the Fourier transform of the k-point
correlation functions at the critical point where the gap is closing.


title:
Anisotropic magnetization and sign change of dynamic susceptibility in
  Na0.85CoO2 single crystal

abstract:
  The DC and AC magnetic susceptibilities of Na0.85CoO2 single crystals were
measured for the different crystal orientations of H//(ab)- and H//(c)-axis.
The DC-magnetic susceptibility for H//(c)-direction exhibited the
antiferromagnetic transition at TN= 22 K. The thermal hysteresis between the
zero-field-cooled (ZFC) and the field-cooled (FC) magnetization below TN and
the large frustration parameter indicated the spin frustration along the
(c)-axis. For an applied magnetic field in H//(ab)-plane, the DC magnetic
susceptibility exhibited the logarithmic divergent behavior at low temperatures
(T < 6.8 K). This could be understood by the impurity spin effect, dressed by
the spin fluctuation. From the AC magnetic susceptibility measurements, the
real part of the AC-susceptibility for H//(ab) exhibited the spin glass-like
behavior at low temperatures (T < 4 K). Remarkably, for an applied AC magnetic
field with H//(c)-axis, the sign of the AC magnetic susceptibility changed from
a positive to a negative value with increasing AC magnetic field frequency (f >
3 kHz) at low temperatures (T > 7 K). We interpret the sign change of AC
magnetic susceptibility along the (c)-axis in terms of the sudden sign reversal
of the phase difference from in-phase to out-of-phase response with an applied
AC magnetic field in the AC-susceptibility phase space.


title:
Assuad-Nagata dimension of nilpotent groups with arbitrary left
  invariant metrics

abstract:
  Suppose $G$ is a countable, not necessarily finitely generated, group. We
show $G$ admits a proper, left-invariant metric $d_G$ such that the
Assouad-Nagata dimension of $(G,d_G)$ is infinite, provided the center of $G$
is not locally finite. As a corollary we solve two problems of A.Dranishnikov.


title:
Stable, Renormalizable, Scalar Tachyonic Quantum Field Theory with
  Chronology Protection

abstract:
  We use microlocal arguments to suggest that Lorentz symmetry breaking must
occur in a reasonably behaved tachyonic quantum field theory that permits
renormalizability. In view of this, we present a scalar tachyonic quantum field
model with manifestly broken Lorentz symmetry and without exponentially
growing/decaying modes. A notion of causality, in which anti-telephones are
excluded, and which is viewed as a form of chronology protection, is obeyed.
The field theory is constructed in a preferred tachyon frame in terms of
commuting creation/annihilation operators. We calculate some sample
(renormalized) operators in this preferred frame, argue that the Hadamard
condition is satisfied, and discuss the PCT and spin-statistics theorems for
this model.


title: A possible solution for the lack of EHB binaries in globular clusters

abstract:
  The binary fraction among extreme horizontal branch (EHB) stars in Galactic
globular clusters (GCs) is an order of magnitude lower than the binary fraction
among their counterparts, field hot subdwarfs. This casts serious doubt on
their formation channels. In this {\em Letter}, I explain the difference
between the field and the cluster EHB stars with the binary model of Han et al.
(2002, 2003) for the formation of EHB stars. With the binary population
synthesis code of Han et al. (2002, 2003), I follow the evolution of simple
stellar populations resulting from single star bursts (note that Han et al.
2002, 2003, adopted a constant star formation rate over the last 15 Gyr for the
production of field EHB stars), and obtain EHB stars at different stellar
population ages. I found that the binary fraction among EHB stars decreases
with the stellar population age. The fraction of EHB binaries with orbital
periods $P<5 {\rm d}$ is $\sim 2.5%$ for a stellar population of 10 Gyr from
the standard simulation set. The binary model of Han et al. (2002, 2003) is
able to explain the lack of EHB binaries in globular clusters. I also propose
that the precise determination of the physical parameters of close EHB binaries
in GCs can lead to the strictest constraint on common-envelope ejection
efficiency.


title: Point spread functions for the Solar Optical Telescope onboard Hinode

abstract:
  The combined PSF of the BFI and the SOT onboard the Hinode spacecraft is
investigated. Observations of the Mercury transit from November 2006 and the
solar eclipse(s) from 2007 are used to determine the PSFs of SOT for the blue,
green, and red continuum channels of the BFI. For each channel large grids of
theoretical point spread functions are calculated by convolution of the ideal
diffraction-limited PSF and Voigt profiles. These PSFs are applied to
artificial images of an eclipse and a Mercury transit. The comparison of the
resulting artificial intensity profiles across the terminator and the
corresponding observed profiles yields a quality measure for each case. The
optimum PSF for each observed image is indicated by the best fit. The observed
images of the Mercury transit and the eclipses exhibit a clear proportional
relation between the residual intensity and the overall light level in the
telescope. In addition there is a anisotropic stray-light contribution. ...
BFI/SOT operate close to the diffraction limit and have only a rather small
stray-light contribution. The FWHM of the PSF is broadened by only ~1% with
respect to the diffraction-limited case, while the overall Strehl ratio is ~
0.8. In view of the large variations -- best seen in the residual intensities
of eclipse images -- and the dependence on the overall light level and position
in the FOV, a range of PSFs should be considered instead of a single PSF per
wavelength. The individual PSFs of that range allow then the determination of
error margins for the quantity under investigation. Nevertheless the
stray-light contributions are here found to be best matched with Voigt
functions with the parameters sigma = 0."008 and gamma = 0."004, 0."005, and
0."006 for the blue, green, and red continuum channels, respectively.


title:
Radio Continuum Study of Supernova Remnants in the Large Magellanic
  Cloud - SNR J0519-6926

abstract:
  We present the results of new high resolution ATCA observations of SNR
J0519-6926. We found that this SNR exhibits a typical "horseshoe" appearance
with alpha = -0.55 +- 0.08 and D=28+-1 pc. No polarization (or magnetic fields)
are detected to a level of 1%. This is probably due to a relatively poor
sampling of the uv plane caused be observing in "snap-shot" mode.


title: Nonlinear Landau-Zener Processes in a Periodic Driving Field

abstract:
  Effects of a periodic driving field on Landau-Zener processes are studied
using a nonlinear two-mode model that describes the mean-field dynamics of a
many-body system. A variety of different dynamical phenomena in different
parameter regimes of the driving field are discussed and analyzed. These
include shifted, weakened, or enhanced phase dependence of nonlinear
Landau-Zener processes, nonlinearity-enhanced population transfer in the
adiabatic limit, and Hamiltonian chaos on the mean field level. The emphasis of
this work is placed on how the impact of a periodic driving field on
Landau-Zener processes with self-interaction differs from those without
self-interaction. Aside from gaining understandings of driven nonlinear
Landau-Zener processes, our findings can be used to gauge the strength of
nonlinearity and for efficient manipulation of the mean-field dynamics of
many-body systems.


title: Optical Spectra of Radio Planetary Nebulae in the Small Magellanic Cloud

abstract:
  We present preliminary results from spectral observations of four candidate
radio sources co-identified with known planetary nebulae (PNe) in the Small
Magellanic Cloud (SMC). These were made using the Radcliffe 1.9-meter telescope
in Sutherland, South Africa. These radio PNe were originally found in Australia
Telescope Compact Array (ATCA) surveys of the SMC at 1.42 and 2.37 GHz, and
were further confirmed by new high resolution ATCA images at 6 and 3 cm
(4"/2"). Optical PNe and radio candidates are within 2" and may represent a
subpopulation of selected radio bright objects. Nebular ionized masses of these
objects may be 2.6 MSol or greater, supporting the existence of PNe progenitor
central stars with masses up to 8 MSol.


title: Nonlinear quantum metrology using coupled nanomechanical resonators

abstract:
  We consider a nanomechanical analogue of a nonlinear interferometer,
consisting of two parallel, flexural nanomechanical resonators, each with an
intrinsic Duffing nonlinearity and with a switchable beamsplitter-like coupling
between them. We calculate the precision with which the strength of the
nonlinearity can be estimated and show that it scales as $1/n^{3/2}$, where $n$
is the mean phonon number of the initial state. This result holds even in the
presence of dissipation, but assumes the ability to make measurements of the
quadrature components of the nanoresonators.


title:
Evidence of molecular adaptation to extreme environments and
  applicability to space environments

abstract:
  This is initial study of a gene signatures responsible for adapting
microscopic life to the life in extreme Earth environments. We present a
results on ID of the clusters of COGs common to several hyperthermophiles and
exclusion of those common to a mesophile: E.coli.K12, will yield a group of
proteins possibly involved in adaptation to life under extreme T. Methanogens
stand out as the only group of organisms that have species capable of growth at
0C (M.frigidum and M.burtonii) and 110C (M.kandleri). Not all the components of
heat adaptation can be attributed to novel genes, the chaperones known as heat
shock proteins stabilize the enzymes under elevated temperature. Highly
conserved chaperons found in bacteria and eukaryots are not present in
hyperthermophilic Archea, rather, they have a unique chaperone TF55. Our aim is
to use software which we specifically developed for extremophile genome
comparative analyses in order to search for additional novel genes involved in
hyperthermophile adaptation. The following hyperthermophile genomes
incorporated in our software were used for these studies: M.jannaschii,
M.kandleri, A.fulgidus and 3 species of Pyrococcus. Common genes were annotated
and grouped according to their roles in cellular processes when information was
available and proteins not previously implicated in the heat-adaptation of
hyperthermophiles were identified. Additional experimental data is needed in
order to learn more about these proteins. To address a non-gene based
components of thermal adaptation, all sequenced extremophiles were analysed for
their GC contents and aminoacid hydrophobicity. We develop a prediction model
for optimal growth temperature.


title: The nuMSM, leptonic asymmetries, and properties of singlet fermions

abstract:
  We study in detail the mechanism of baryon and lepton asymmetry generation in
the framework of the $\nu$MSM (an extension of the Standard Model by three
singlet fermions with masses smaller than the electroweak scale). We elucidate
the issue of CP-violation in the model and define the phase relevant for
baryogenesis. We clarify the question of quantum-mechanical coherence,
essential for the lepton asymmetry generation in singlet fermion oscillations
and compute the relevant damping rates. The range of masses and couplings of
singlet leptons which can lead to successful baryogenesis is determined. The
conditions which ensure survival of primordial (existing above the electroweak
temperatures) asymmetries in different leptonic numbers are analysed. We
address the question whether CP-violating reactions with lepton number
non-conservation can produce leptonic asymmetry {\em below} the sphaleron
freeze-out temperature. This asymmetry, if created, leads to resonant
production of dark matter sterile neutrinos. We show that the requirement that
a significant lepton asymmetry be produced puts stringent constraints on the
properties of a pair of nearly degenerate singlet fermions, which can be tested
in accelerator experiments. In this region of parameters the $\nu$MSM provides
a common mechanism for production of baryonic matter and dark matter in the
universe. We analyse different fine-tunings of the model and discuss possible
symmetries of the $\nu$MSM Lagrangian that can lead to them.


title:
Sterile neutrino dark matter as a consequence of nuMSM-induced lepton
  asymmetry

abstract:
  It has been pointed out in ref.[1] that in the nuMSM (Standard Model extended
by three right-handed neutrinos with masses smaller than the electroweak
scale), there is a corner in the parameter space where CP-violating resonant
oscillations among the two heaviest right-handed neutrinos continue to operate
below the freeze-out temperature of sphaleron transitions, leading to a lepton
asymmetry which is considerably larger than the baryon asymmetry. Consequently,
the lightest right-handed (``sterile'') neutrinos, which may serve as dark
matter, are generated through an efficient resonant mechanism proposed by Shi
and Fuller [2]. We re-compute the dark matter relic density and non-equilibrium
momentum distribution function in this situation with quantum field theoretic
methods and, confronting the results with existing astrophysical data, derive
bounds on the properties of the lightest right-handed neutrinos. Our spectra
can be used as an input for structure formation simulations in warm dark matter
cosmologies, for a Lyman-alpha analysis of the dark matter distribution on
small scales, and for studying the properties of haloes of dwarf spheroidal
galaxies.


title:
Modification of the electronic structure in a carbon nanotube with the
  charge dopant encapsulation

abstract:
  We present the first-principles study of effects of the charge dopants such
as Cesium and Iodine encapsulated on the electronic structure of carbon
nanotubes. An encapsulated cesium atom donates an electron to the nanotube and
produces donor-like states below the conduction bands. In contrast, an iodine
trimer (I$_{3}$) accepts an electron from the nanotube and produces an
acceptor-like state above the valance band maximum. We find that a Cs atom
inside a metallic armchair carbon nanotube gives rise to spatial oscillations
of the density of states near the Fermi level.