title: A study of high velocity molecular outflows with an up-to-date sample

abstract:
  A statistical study of the properties of molecular outflows is performed
based on an up-to-date sample. 391 outflows were identified in published
articles or preprints before February 28, 2003. The parameters of position,
morphology, mass, energy, outflow dynamics and central source luminosity are
presented for each outflow source. Outflow lobe polarity is known for all the
sources, and 84% are found to be bipolar. The sources are divided into low mass
and high mass groups according to either the available bolometric luminosity of
the central source or the outflow mass.Energetic mass ejection may be a common
aspect of the formation of high mass as well as low mass stars. Outflow masses
are correlated strongly with bolometric luminosity of the center sources, which
was obtained for the first time. There are also correlations between the
central source luminosity and the parameters of mechanical luminosity and the
thrust or force necessary to drive the outflow. The results show that flow
mass, momentum and energy depend on the nature of the central source. Despite
their similarity, there are differences between the high mass and low mass
outflows on collimation, flow masses, mass-dynamical time relation and
associated objects such as HH objects and water masers.Sources with
characteristics of collapse or infall comprise 12% of the entire outflow
sample. The spatial distribution of the outflow sources in the Galaxy is
presented and the local occurrence rate is compared with the stellar birth
rate.


title:
A Unified Model of Short and Long Gamma-Ray Bursts, X-Ray Rich Gamma-Ray
  Bursts, and X-Ray Flashes

abstract:
  We propose a possible unified model of short and long gamma-ray bursts
(GRBs), X-ray rich GRBs, and X-ray flashes. The jet of a GRB is assumed to
consist of multiple sub-jets or sub-shells (i.e., an inhomogeneous jet model).
The multiplicity of the sub-jets along a line of sight n_s is an important
parameter. If n_s is large (>> 1) the event looks like a long GRB, while if
n_s=1, the event looks like a short GRB. Finally, when n_s=0, the event looks
like an X-ray flash or an X-ray rich GRB. Furthermore, our model may also
explain the bimodal distributions of T_{90} duration of BATSE-GRBs.


title:
Geodynamo alpha-effect derived from box simulations of rotating
  magnetoconvection

abstract:
  The equations for fully compressible rotating magnetoconvection are
numerically solved in a Cartesian box assuming conditions roughly suitable for
the geodynamo. The mean electromotive force describing the generation of mean
magnetic flux by convective turbulence in the rotating fluid is directly
calculated from the simulations, and the corresponding alpha-coefficients are
derived. Due to the very weak density stratification the alpha-effect changes
its sign in the middle of the box. It is positive at the top and negative at
the bottom of the convection zone. For strong magnetic fields we also find a
clear downward advection of the mean magnetic field. Both of the simulated
effects have been predicted by quasi-linear computations (Soward, 1979;
Kitchatinov and Ruediger, 1992). Finally, the possible connection of the
obtained profiles of the EMF with mean-field models of oscillating
alpha^2-dynamos is discussed.


title: A-type stars: evolution, rotation and binarity

abstract:
  We discuss the internal structure of stars in the mass range 1.5 to 4 M_sun
from the PMS to the subgiant phase with a particular emphasis on the convective
core and the convective superficial layers. Different physical aspects are
considered such as overshooting, treatment of convection, microscopic diffusion
and rotation. Their influence on the internal structure and on the photospheric
chemical abundances is briefly described. The role of binarity in determining
the observed properties and as a tool to constrain the internal structure is
also introduced and the current limits of theories of orbital evolution and of
available binary data--sets are discussed. keywords{stars: evolution, stars:
binaries: general, stars: rotation}


title:
Consistent Radiative Transfer Models including Time Dependent Energy
  Deposition for Type Ia Supernovae

abstract:
  Many aspects of the explosion mechanism of Type Ia supernovae (SN Ia) still
remain unclear -- causing uncertainties in the derived cosmological parameters.
Realistic models of the generation and transport of radiation in the ejecta are
required which link theoretical explosion models to observations. We aim to
construct theoretical spectra and light curves from consistent radiative
transfer models that allow to study the dependence of observable features on
the physical parameters of the explosion.


title:
Statistical properties of exoplanets IV. The period--eccentricity
  relations of exoplanets and of binary stars

abstract:
  A sample of spectroscopic binaries and a sample of single planetary systems,
both having main-sequence solar-type primary components, are selected in order
to compare their eccentricities. The positions of the objects in the
(P.(1-e^2)^(3/2), e) plane is used to determine parts in the
period-eccentricity diagram that are not affected by tidal circularization. The
original eccentricities of binaries and planets are derived and compared. They
seem to be weakly or not at all correlated with period in both samples, but two
major differences are found :(1) The tidal circularization of planetary orbits
is almost complete for periods shorter than 5 days, but it is not visible when
P.(1-e^2)^{3/2} is longer than this limit. This suggests that the
circularization occurs rapidly after the end of the migration process and is
probably simultaneous with the end of the formation of the planet. By contrast,
we confirm that the circularization of the binary orbits is a process still
progressing a long time after the formation of the systems.(2) Beyond the
circularization limit, the eccentricities of the orbits of the planets are
significantly smaller than those of binary orbits, and this discrepancy cannot
be due to a selection effect. Moreover, the eccentricities of binaries with
small mass ratios are quite similar to those of all binaries with q<0.8. This
suggests that the low eccentricities of exoplanet orbits are not a consequence
of low-mass secondaries in a universal process.
  These remarks are in favor of the idea that binaries and exoplanets are two
different classes of object from the point of view of their formation.


title: The Formation of Population III Binaries

abstract:
  We explore the possibility for the formation of Population III binaries. The
collapse of a rotating cylinder is simulated with a three-dimensional,
high-resolution nested grid, assuming the thermal history of primordial gas.
The simulations are done with dimensionless units, and the results are
applicable to low-mass as well as massive systems by scaling with the initial
density. We find that if the initial angular momentum is as small as $\beta
\approx 0.1$, where $\beta$ is the ratio of centrifugal force to pressure
force, then the runaway collapse of the cloud stops to form a
rotationally-supported disk. After the accretion of the envelope, the disk
undergoes a ring instability, eventually fragmenting into a binary. If the
initial angular momentum is relatively large, a bar-type instability arises,
resulting in the collapse into a single star through rapid angular momentum
transfer. The present results show that a significant fraction of Pop III stars
are expected to form in binary systems, even if they are quite massive or less
massive. The cosmological implications of Population III binaries are briefly
discussed.


title:
The Distribution of Pressures in a Supernova-Driven Interstellar Medium.
  I. Magnetized Medium

abstract:
  Observations have suggested substantial departures from pressure equilibrium
in the interstellar medium (ISM) in the plane of the Galaxy, even on scales
under 50 pc. Nevertheless, multi-phase models of the ISM assume at least
locally isobaric gas. The pressure then determines the density reached by gas
cooling to stable thermal equilibrium. We use numerical models of the
magnetized ISM to examine the consequences of supernova driving for
interstellar pressures. In this paper we examine a (200 pc)^3 periodic domain
threaded by magnetic fields. Individual parcels of gas at different pressures
reach widely varying points on the thermal equilibrium curve: no unique set of
phases is found, but rather a dynamically-determined continuum of densities and
temperatures. A substantial fraction of the gas remains entirely out of thermal
equilibrium. Our results appear consistent with observations of interstellar
pressures. They also suggest that the high pressures observed in molecular
clouds may be due to ram pressures in addition to gravitational forces. Much of
the gas in our model lies far from equipartition between thermal and magnetic
pressures, with ratios ranging from 0.1 to $10^4$ and ratios of uniform to
fluctuating magnetic field of 0.5--1. Our models show broad pressure
probability distribution functions with log-normal functional forms produced by
both shocks and rarefaction waves, rather than power-law distributions produced
by isolated supernova remnants. The width of the distribution can be described
quantitatively by a formula derived from the work of Padoan, Nordlund, & Jones
(1997).


title: Low Energy Hadronic Interaction Models

abstract:
  Different interaction models treating hadronic collisions below E_lab < 100
GeV in air shower simulations are compared within the frame of the CORSIKA
program. Their behaviour is studied in isolated collisions of protons or pions
with light-mass targets in comparison with experimental data. It is discussed
how model properties influence air-shower parameters like the longitudinal
profile or the lateral distribution of particles arriving at ground.


title: Structure of the Galactic Halo towards the North Galactic Pole

abstract:
  We have used RR Lyrae and Blue HB stars as tracers of the old Galactic halo,
in order to study the halo structure and the galactic rotation as a function of
height above the plane. Our sample includes 40 RR Lyrae and 80 BHB stars that
are about 2 to 15 kpc above the plane, in a roughly 250 sq. deg. area around
the North Galactic Pole (NGP). We use proper motions (derived from the GSC-II
database) and radial velocities to determine the rotation of the halo. From the
whole sample the motion appears to be significantly more retrograde than the
samples in the solar neighborhood, confirming Majewski (1992) results and our
own preliminary results based on 1/3 the present sample (Kinman et al. 2003;
Spagna et al. 2003). However, the better statistics has now revealed the likely
existence of two components, whose characteristics need an accurate analysis of
systematic errors on the proper motions in order to be assessed in detail.


title: Spectropolarimetry of single and binary stars

abstract:
  Spectropolarimetry is a photon-hungry technique that will reach fruition in
the 8-m telescope age. Here I summarize some of the stellar spectropolarimetric
research that my collaborators and I have undertaken, with particular emphasis
on the circumstellar environment of massive stars, symbiotic binaries, and star
formation.


title: Changing universe model of redshift

abstract:
  The changing universe model (CUM) describes galaxy parameter relationships
(SESAPS '03, session EB 2). The CUM must be successfully applied to
cosmological scale observations to be considered a cosmological model. A major
component of current cosmological models is the Hubble constant $H_\mathrm{o}$.
An equation is derived using the CUM model relating redshift $z$ and the
distance $D$ to galaxies and is applied to a sample of 32 spiral galaxies with
$D$ calculated using Cepheid variable stars. The equation predicts a galaxy may
have $z<0$ in special circumstances. Three elliptical galaxies with peculiar
characteristics are discovered to be CUM Sinks. The Sinks give a physical
explanation of the ``Virgocentric infall'' and ``Great Attractor'' observations
without a large, unobserved mass. At low cosmological distances, the equation
reduces to $z \approx \exp(KD) -1 \approx KD$, where $K$ is a constant,
positive value. The equation predicts $z$ from galaxies over 23 Gpc distant
approaches a constant value on the order of 1000. The CUM gives a physical
basis for the Doppler shift of particle photons.


title: On the primary particle type of the most energetic Fly's Eye event

abstract:
  The longitudinal profile of the 320 EeV event observed by the Fly's Eye
experiment is analysed. A method of testing the hypothesis of a specific
primary particle type is described. Results for different particle types are
summarized. For hadronic primaries between proton and iron nuclei, the
discrepancy between observed and simulated profiles is in the range of 0.6-1.0
sigma for two different hadronic interaction models investigated. For primary
photons, the discrepancy is 1.5sigma assuming a standard extrapolation of the
photonuclear cross-section with energy. Larger values of the cross-section at
highest energies make primary photon showers more similar to hadron-initiated
events. The influence of varying the extrapolation of the photonuclear
cross-section is studied.


title: Large scale inhomogeneity and local dynamical friction

abstract:
  We investigate the effect of a density gradient on Chandrasekhar's dynamical
friction formula based on the method of 2-body encounters in the local
approximation. We apply these generalizations to the orbit evolution of
satellite galaxies in Dark Matter haloes. We find from the analysis that the
main influence occurs through a position-dependent maximum impact parameter in
the Coulomb logarithm, which is determined by the local scale-length of the
density distribution. We also show that for eccentric orbits the explicit
dependence of the Coulomb logarithm on position yields significant differences
for the standard homogeneous force. Including the velocity dependence of the
Coulomb logarithm yields ambigous results. The orbital fits in the first few
periods are further improved, but the deviations at later times are much
larger. The additional force induced by the density gradient, the inhomogeneous
force, is not antiparallel to the satellite motion and can exceed 10% of the
homogeneous friction force in magnitude. However, due to the symmetry
properties of the inhomogeneous force, there is a deformation and no secular
effect on the orbit at the first order. Therefore the inhomogeneous force can
be safely neglected for the orbital evolution of satellite galaxies. For the
homogeneous force we compare numerical N-body calculations with semi-analytical
orbits to determine quantitatively the accuracy of the generalized formulae of
the Coulomb logarithm in the Chandresekhar approach. With the local
scale-length as the maximum impact parameter we find a significant improvement
of the orbital fits and a better interpretation of the quantitative value of
the Coulomb logarithm.


title:
A comparative study of correlations between arrival directions of
  ultra-high-energy cosmic rays and positions of their potential astrophysical
  sources

abstract:
  We consider various classes of persistent extragalactic astrophysical sources
which have been suggested in literature as possible emitters of
ultra-high-energy cosmic rays (UHECR). We compare the strength of the claimed
correlations by a uniform procedure for all classes of sources by making use of
the AGASA, Yakutsk and HiRes stereo data. BL Lac type objects correlate with
the cosmic rays detected by all three independent experiments and are more
probably, compared to other astrophysical sources, related to the UHECR origin.
With the account of the Galactic magnetic field (not possible for the HiRes
data at the moment), apart of BL Lac type objects, unidentified gamma-ray
sources may be correlated with AGASA and Yakutsk cosmic rays.


title:
Probing the Light Speed Anisotropy with respect to the Cosmic Microwave
  Background Radiation Dipole

abstract:
  We have studied the angular fluctuations in the speed of light with respect
to the apex of the dipole of Cosmic Microwave Background (CMB) radiation using
the experimental data obtained with GRAAL facility, located at the European
Synchrotron Radiation Facility (ESRF) in Grenoble. The measurements were based
on the stability of the Compton edge of laser photons scattered on the 6 GeV
monochromatic electron beam. The results enable to obtain a conservative
constraint on the anisotropy in the light speed variations \Delta c(\theta)/c <
3 10^{-12}, i.e. with higher precision than from previous experiments.


title:
Spectroscopic study of blue compact galaxies IV. Star formation rates
  and gas depletion timescales

abstract:
  This is the fourth paper in a series studying star formation rates, stellar
components, metallicities, and star formation histories of a blue compact
galaxy (BCG) sample. Using Ha, [OII]3727, IR, radio (1.4GHz) luminosities and
neutral hydrogen gas masses, we estimated star formation rates(SFR) and gas
depletion timescales of 72 star-forming BCGs. The SFRs of the BCGs in our
sample span nearly four orders of magnitude, from approximately 10^-2 to
10^2M_sun/yr, with a median SFR of about 3M_sun/yr. The typical gas depletion
timescale of BCGs is about one billion years.
  We found that subtracting underlying stellar absorption is very important to
calculate both dust extinction and SFR of galaxies. Otherwise, the intrinsic
extinction will be overestimated, the SFRs derived from [OII] and Ha will be
underestimated (if the underlying stellar absorption and the internal
extinction were not corrected from the observed luminosity) or overestimated
(if an overestimated internal extinction were used for extinction correction).
After both the underlying stellar absorption and the dust extinction were
corrected, a remarkably good correlation emerges among Ha, [OII], IR and radio
SFR indicators. Finally, we find a good correlation between the measured SFR
and the absolute blue magnitude, metallicity, interstellar extinction of BCGs.
Our results indicate that faint, low-mass BCGs have lower star formation rates.


title: Up-dated opacities from the Opacity Project

abstract:
  Using the code AUTOSTRUCTURE, extensive calculations of inner-shell atomic
data have been made for the chemical elements He, C, N, O, Ne, Na, Mg, Al, Si,
S, Ar, Ca, Cr, Mn, Fe and Ni. The results are used to obtain up-dated opacities
from the Opacity Project, OP. A number of other improvements on earlier work
have also been included.
  Rosseland-mean opacities from OP are compared with those from OPAL.
Differences of 5 to 10% occur. OP gives the `Z-bump', at log(T)=5.2, to be
shifted to slightly higher temperatures. The opacities from OP, as functions of
temperature and density, are smoother than those from OPAL. Extensive tests
show that the numerical accuracy of the OP opacities following integration over
frequency mesh and interpolation on temperature-density mesh is better than 1%.
  Prior to a number of recent investigations which have indicated a need for a
downward revision in the solar abundances of oxygen and other elements, there
was good agreement between properties of the sun deduced from helioseismology
and from stellar evolution models calculated using OPAL opacities. The
revisions in abundances destroy that agreement. In a recent paper Bahcall et al
argue that the agreement would be restored if opacities for the regions of the
sun between 0.7 and 0.4 solar radii were larger than those given by OPAL by
about 10%. In the region concerned, the present results from OP do not differ
from those of OPAL by more than 2.5%.


title:
Stability of Accretion Disc around a Black Hole: effects of
  Bremsstrahlung and Synchrotron Cooling

abstract:
  We perform stability analysis of an accretion disc around a stellar mass
black hole. The cooling of the accretion flow due to bremsstrahlung and
synchrotron radiation processes are considered. The solutions with shock are
perturbed at the shock location and the radial dependence of perturbation is
obtained by solving the equations numerically using fourth-order Runge-Kutta
method. The perturbations are assumed to be infinitesimal, thereby allowing a
linear analysis. The frequencies that solve the equations are found and the
existence of unstable frequencies implies instability.


title:
Scientific requirements of ALMA, and its capabilities for key-projects:
  Extragalactic

abstract:
  The Atacama Large Millimeter Array (ALMA) consists of 64 antennas of 12m
diameter that will initially observe in 4 frequency bands between 84 and 720
GHz with spatial resolutions down to 0.01" and velocity resolutions as fine as
0.05 km/s. These technical requirements are based on three primary science
goals. We illustrate two of these requirements: (i) the ability to detect
spectral line emission from a Milky-Way type galaxy at z=3, and (ii) the
ability to provide precise images at an angular resolution of 0.1". Finally, we
present a possible large extragalactic project with ALMA: molecular line
studies of submm galaxies.


title: The Massive Runaway Stars HD 14633 and HD 15137

abstract:
  We present results from a radial velocity study of two runaway O-type stars,
HD 14633 (ON8.5 V) and HD 15137 (O9.5 III(n)). We find that HD 14633 is a
single-lined spectroscopic binary with an orbital period of 15.4083 days. The
second target HD 15137 is a radial velocity variable and a possible
single-lined spectroscopic binary with a period close to 1 month. Both binaries
have large eccentricity, small semiamplitude, and a small mass function. We
show the trajectories of the stars in the sky based upon an integration of
motion in the Galactic potential, and we suggest that both stars were ejected
from the vicinity of the open cluster NGC 654 in the Perseus spiral arm. The
binary orbital parameters and runaway velocities are consistent with the idea
that both these stars were ejected by supernova explosions in binaries and that
they host neutron star companions. We find that the time-of-flight since
ejection is longer than the predicted evolutionary timescales for the stars,
which may indicate that they have a lower mass than normally associated with
their spectral classifications and/or that their lives have been extended
through rapid rotation.


title: Molecular Line Profile Fitting with Analytic Radiative Transfer Models

abstract:
  We present a study of analytic models of starless cores whose line profiles
have ``infall asymmetry,'' or blue-skewed shapes indicative of contracting
motions. We compare the ability of two types of analytical radiative transfer
models to reproduce the line profiles and infall speeds of centrally condensed
starless cores whose infall speeds are spatially constant and range between 0
and 0.2 km s-1. The model line profiles of HCO+ (J=1-0) and HCO+ (J=3-2) are
produced by a self-consistent Monte Carlo radiative transfer code. The analytic
models assume that the excitation temperature in the front of the cloud is
either constant (``two-layer'' model) or increases inward as a linear function
of optical depth (``hill'' model). Each analytic model is matched to the line
profile by rapid least-squares fitting.
  The blue-asymmetric line profiles with two peaks, or with a blue shifted peak
and a red shifted shoulder, can be well fit by the ``HILL5'' model (a five
parameter version of the hill model), with an RMS error of 0.02 km s-1. A peak
signal to noise ratio of at least 30 in the molecular line observations is
required for performing these analytic radiative transfer fits to the line
profiles.


title:
Chemical abundances of RGB-Tip stars in the Sagittarius dwarf Spheroidal
  galaxy

abstract:
  We present preliminary iron abundances and $\alpha$ element (Ca, Mg)
abundance ratios for a sample of 22 Red Giant Branch (RGB) Stars in the
Sagittarius dwarf spheroidal galaxy (Sgr), selected near the RGB-Tip. The
sample is representative of the Sgr dominant population. The mean iron
abundance is [Fe/H]=-0.49. The $\alpha$ element abundance ratios are slightly
subsolar, in agreement with the results recently prensented by Bonifacio et
al.(2004, A&A, 414, 503).


title:
The Initial Configuration of Young Stellar Clusters: A K-band Number
  Counts Analysis of the Surface Density of Stars

abstract:
  We present an analysis of K-band stellar distributions for the young stellar
clusters GGD 12-15, IRAS 20050+2720, and NGC 7129. We find that the two deeply
embedded clusters, GGD 12-15 and IRAS 20050+2720, are not azimuthally symmetric
and show a high degree of structure which traces filamentary structure observed
in 850 micron emission maps. In contrast, the NGC 7129 cluster is circularly
symmetric, less dense, and anti-correlated to 850 micron emission, suggesting
recent gas expulsion and dynamical expansion have occured. We estimate stellar
volume densities from nearest neighbor distances, and discuss the impact of
these densities on the evolution of circumstellar disks and protostellar
envelopes in these regions.


title:
Accurate determination of the mass distribution in spiral galaxies III.
  Fabry-Perot imaging spectroscopy of 6 spiral galaxies

abstract:
  High resolution Fabry-Perot data of six spiral galaxies are presented. Those
data extend the previous sample of spiral galaxies studied with high resolution
3D spectroscopy to earlier morphological types. All the galaxies in the sample
have available HI data at 21 cm from the VLA or Westerbork. Velocity fields are
analyzed and Halpha rotation curves are computed and compared to HI curves. The
kinematics of NGC 5055 central regions are looked at more closely. Its peculiar
kinematics can be interpreted either as a bipolar outflow or as a
counter-rotating disk, possibly hosting a 9 pm 2 10^8 Msol compact object. Most
of the Halpha rotation curves present a significantly steeper inner slope than
their HI counterparts. The 21 cm data thus seems affected by moderate to strong
beam smearing. The beam smearing has an effect at higher
scale-length/beam-width than previously thought (up to 20 km/s at a ratio of
8.5).


title:
UVES detailed chemical abundances in the Sgr dSph and the CMa
  overdensity

abstract:
  We present detailed Chemical abundances for 12 stars in the Sagittarius Dwarf
Spheroidal Galaxy (Sgr dSph) and 3 in the Canis Mayor Overdensity (CMa), based
on UVES spectra. Sgr dSph stars present high metallicity ([Fe/H] between -1 and
0) low [alpha/Fe] ratios, overabundant La, Ce and Nd, underabundant Na, Al,Ni
and Zn. Zn underabundance in particular is interesting, since it may undermine
the parallel drawn between dSph and DLAs, where Zn is used as a proxy for Fe.
Of the three CMa stars, one is likely a Milky Way (MW) interloper, the other
two present solar metallicity, underabundant alpha elements and overabundant
La, Ce and Nd. These features are strongly resembling what found in Sgr dSph.
Moreover, a significant Cu overabundance is detected ([Cu/Fe] ~ +0.25), unusual
for MW disk stars. In our opinion these results strongly point toward the
presence, in the CMa overdensity, of an accreted stellar population of
extragalactic origin.


title: Discovery of an X-ray Nova in M31

abstract:
  We have obtained snapshot images of an X-ray nova in M31 from Chandra ACIS-I
and the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The
Chandra position of the X-ray nova was R.A.=00:44:06.68 +/- 1.74",
Dec.=+41:12:20.0 +/- 2.31". A follow-up HST observation 24 days later revealed
a source at R.A.=00:44:06.81, Dec.=+41:12:24.0 that was B=25.75 +/- 0.05. This
optical source faded to B=27.1 +/- 0.1 in 3 months. During this time period,
the X-ray flux decayed linearly from (3.6 +/- 0.2) X 10^{-4} to <(6.9 +/- 0.09)
X 10^{-5} ct cm^{-2} s^{-1}. The HST identification of an optical source in the
same region experiencing an obvious drop in brightness in concert with the
X-ray nova suggests that this optical source is the counterpart of the X-ray
nova. However, the precision of the X-ray position allows the possibility that
the optical source is a nearby variable star. We discuss the implications of
both possibilities.


title: Migration of Small Bodies and Dust to Near-Earth Space

abstract:
  The orbital evolution of Jupiter-family comets (JFCs), resonant asteroids,
and asteroidal, trans-Neptunian, and cometary dust particles under the
gravitational influence of planets was integrated. For dust particles we also
considered radiation pressure, Poynting-Robertson drag, and solar wind drag.
The probability of a collision of one former JFC with a terrestrial planet can
be greater than analogous total probability for thousands other JFCs. If those
former JFCs that got near-Earth object (NEO) orbits for millions of years
didn't disintegrate during this time, there could be many extinct comets among
NEOs. The maximum probability of a collision of an asteroidal or cometary dust
particle with the Earth during its lifetime was for diameter $d$$\sim$100
microns. At $d$$<$10 micron, the collision probability of a trans-Neptunian
particle with the Earth during a lifetime of the particle was less than that
for an asteroidal particle by only a factor of several.


title: Migration of Small Bodies and Dust to the Terrestrial Planets

abstract:
  We integrated the orbital evolution of 30,000 Jupiter-family comets, 1300
resonant asteroids, and 7000 asteroidal, trans-Neptunian, and cometary dust
particles. For initial orbital elements of bodies close to those of Comets 2P,
10P, 44P, and 113P, a few objects got Earth-crossing orbits with semi-major
axes $a$$<$2 AU and moved in such orbits for more than 1 Myr (up to tens or
even hundreds of Myrs). Four objects (from 2P and 10P runs) even got
inner-Earth orbits (with aphelion distance $Q$$<$0.983 AU) and Aten orbits for
Myrs. Our results show that the trans-Neptunian belt can provide a significant
portion of near-Earth objects, or the number of trans-Neptunian objects
migrating inside the solar system can be smaller than it was earlier
considered, or most of 1-km former trans-Neptunian objects that had got
near-Earth object orbits for millions of years disintegrated into mini-comets
and dust during a smaller part of their dynamical lifetimes. The probability of
a collision of an asteroidal or cometary particle during its lifetime with the
Earth was maximum at diameter $d$$\sim$100 $\mu$m. At $d$$<$10 $\mu$m such
probability for trans-Neptunian particles was less than that for asteroidal
particles by less than an order of magnitude, so the fraction of
trans-Neptunian particles with such diameter near Earth can be considerable.


title:
Abundance Profiles and Kinematics of Damped Lyman-alpha Absorbing
  Galaxies at z < 0.65

abstract:
  We present a spectroscopic study of six damped Lya absorption (DLA) systems
at z<0.65, based on moderate-to-high resolution spectra of the galaxies
responsible for the absorbers. Combining known metallicity measurements of the
absorbers with known optical properties of the absorbing galaxies, we confirm
that the low metal content of the DLA population can arise naturally as a
combination of gas cross-section selection and metallicity gradients commonly
observed in local disk galaxies. We also study the Tully-Fisher relation of the
DLA-selected galaxies and find little detectable evidence for evolution in the
disk population between z=0 and z~0.5. Additional results of our analysis are
as follows. (1) The DLA galaxies exhibit a range of spectral properties, from
post-starburst, to normal disks, and to starburst systems, supporting the idea
that DLA galaxies are drawn from the typical field population. (2) Large
rotating HI disks of radius 30 h^{-1} kpc and of dynamic mass M_dyn > 10^{11}
h^{-1} M_sun appear to be common at intermediate redshifts. (3) Using an
ensemble of six galaxy-DLA pairs, we derive an abundance profile that is
characterized by a radial gradient of -0.041 +/- 0.012 dex per kiloparsec (or
equivalently a scale length of 10.6 h^{-1} kpc) from galactic center to 30
h^{-1} kpc radius. (4) Adopting known N(HI) profiles of nearby galaxies and the
best-fit radial gradient, we further derive an N(HI)-weighted mean metallicity
<Z>_weighted = -0.50 +/- 0.07 for the DLA population over 100 random lines of
sight, consistent with <Z>_weighted = -0.64 (-0.86, +0.40) observed for z~1 DLA
systems from Prochaska et al. Our analysis demonstrates that the low metal
content of DLA systems does not rule out the possibility that the DLA
population trace the field galaxy population.


title: Status of ANITA and ANITA-lite

abstract:
  We describe a new experiment to search for neutrinos with energies above 3 x
10^18 eV based on the observation of short duration radio pulses that are
emitted from neutrino-initiated cascades. The primary objective of the
ANtarctic Impulse Transient Antenna (ANITA) mission is to measure the flux of
Greisen-Zatsepin-Kuzmin (GZK) neutrinos and search for neutrinos from Active
Galactic Nuclei (AGN). We present first results obtained from the successful
launch of a 2-antenna prototype instrument (called ANITA-lite) that circled
Antarctica for 18 days during the 03/04 Antarctic campaign and show preliminary
results from attenuation length studies of electromagnetic waves at radio
frequencies in Antarctic ice. The ANITA detector is funded by NASA, and the
first flight is scheduled for December 2006.


title: The White Dwarf Luminosity Function: The Shape of Things to Come

abstract:
  We describe a new survey for cool white dwarfs that supplements Sloan Digital
Sky Survey photometry with USNO proper motions and follow-up spectroscopy. To
date we have discovered and spectroscopically confirmed 80 new moderate
temperature and cool white dwarfs. We have also found a handful of
high-velocity white dwarfs and we expect a sizable fraction of these to be
thick disk or possibly halo objects. Our survey is designed to find ~10,000 new
white dwarfs, although only ~60 will be among the faintest white dwarfs (M(V)
>= 16), where most of the age-sensitivity resides. We discuss an extension of
our survey to V ~ 22.


title: White Dwarfs in Open Clusters: Calibrating the Clock

abstract:
  We present an update of our on-going effort to improve the precision of white
dwarf cosmochronology via careful analyses of white dwarf photometry in open
clusters. To improve the precision of white dwarf and main sequence age
analysis, we are developing a new interpretative scheme using a Bayesian
statistical approach that matches observations to simulated stellar clusters.
Here we present our first tests of the Bayesian approach with simulated stellar
clusters with ages of 1, 2, and 4 billion years.


title: OP data on CD for mean opacities and radiative accelerations

abstract:
  All monochromatic opacity data from the Opacity Project (OP), together with
all codes required for the calculation of mean opacities and radiative
accelerations for any required chemical mixture, temperature and mass-density,
are being put on a 700 Mb CD which will be made generally available. The
present paper gives a concise summary of the contents of the CD. More complete
documentation will be provided on the CD itself.


title:
Connection between the X-ray, UV and optical emission line regions of
  AGNs

abstract:
  In order to investigate the connection between the X-ray, UV and optical
spectral line regions, we selected a sample of AGN which have the strong Fe
K-alpha line and analyze the UV and optical spectral lines.
  Here we present an example of AGN NGC 3516. In this object it seems that
geometries of all three emitting regions are similar, i.e. the broad line
shapes can be explained by the multicomponent emitting line region with a disk
emission. The disk emission contributes to the wings, while one (spherical)
emitting region contributes to the line core. Concerning the Fe K-alpha, UV and
Balmer line shapes it seems that these broad line emitting regions in NGC 3516
are geometrically similar, i.e. in all wavelengths the lines are emitted partly
from the disk partly from a spherical region.


title:
Probing the wind-wind collision in Gamma Velorum with high-resolution
  Chandra X-ray spectroscopy: evidence for sudden radiative braking and
  non-equilibrium ionization

abstract:
  We present a new analysis of an archived Chandra HETGS X-ray spectrum of the
WR+O colliding wind binary Gamma Velorum. The spectrum is dominated by emission
lines from astrophysically abundant elements: Ne, Mg, Si, S and Fe. From a
combination of broad-band spectral analysis and an analysis of line flux ratios
we infer a wide range of temperatures in the X-ray emitting plasma (~4-40 MK).
As in the previously published analysis, we find the X-ray emission lines are
essentially unshifted, with a mean FWHM of 1240 +/- 30 km/s. Calculations of
line profiles based on hydrodynamical simulations of the wind-wind collision
predict lines that are blueshifted by a few hundred km/s. The lack of any
observed shift in the lines may be evidence of a large shock-cone opening
half-angle (> 85 degrees), and we suggest this may be evidence of sudden
radiative braking. From the R and G ratios measured from He-like
forbidden-intercombination-resonance triplets we find evidence that the Mg XI
emission originates from hotter gas closer to the O star than the Si XIII
emission, which suggests that non-equilibrium ionization may be present.


title: Robust Signatures of the Relic Neutrinos in CMB

abstract:
  When the perturbations forming the acoustic peaks of the cosmic microwave
background (CMB) reentered the horizon and interacted gravitationally with all
the matter, neutrinos presumably comprised 41% of the universe energy. CMB
experiments have reached a capacity to probe this background of relic
neutrinos. I review the neutrino impact on the CMB at the onset of the acoustic
oscillations. The discussion addresses the underlying physics, robustness or
degeneracy of the neutrino imprints with changes of free cosmological
parameters, and non-minimal models for the unseen radiation sector with
detectable signatures in CMB anisotropy and polarization.


title: Infrared Photometry of NGC 6791

abstract:
  We present deep JHK photometry of the old and metal-rich open cluster NGC
6791. The photometry reaches below the main sequence turn-off to K = 16.5 mag.
We combine our photometry with that from Stetson, Bruntt, & Grundahl (2003) to
provide color-magnitude diagrams showing K vs. J-K, K vs. V-K, and V vs. V-K.
We study the slope of the red giant branch in the infrared, but find that it is
not a useful metallicity indicator for the cluster, nor any metal-rich cluster
that lacks a well-populated red giant branch, because it is not linear, as has
often been assumed, in K vs. J-K. The mean color of the red horizontal
branch/red clump stars provide an estimate the cluster reddening, E(B-V) = 0.14
+/- 0.04 mag for [Fe/H] = +0.4 +/- 0.1. The mean magnitudes of these stars also
provide a good distance estimate, (m-M)_0 = 13.07 +/- 0.04. Finally, we find
that the isochrones of Yi, Kim, & Demarque (2003) provide optimal fits in V vs.
B-V and V-K and K vs. J-K and V-K for such values if [Fe/H] lies between +0.3
and +0.5 (with a slight preference for +0.5) and ages between 9 Gyrs ([Fe/H] =
+0.3) and 7.5 Gyrs ([Fe/H] = +0.5).


title: The nature of the faint sub-mJy radio population

abstract:
  The up-turn in Euclidean normalised source counts below 1mJy at 1.4GHz is
well established in many deep radio surveys. There are strong reasons,
observationally and theoretically, to believe that this up-turn is due to
strong evolution of the starforming population up to z=2. However this
hypothesis needs further confirmation spectroscopically and the examples in the
literature are sparse. Theoretically the up-turn is well modelled by the
evolution of the local radio starforming population and is consistent with the
up-turn seen in recent mid-infrared source counts at 15um (ISOCAM) and 24um
(Spitzer) and the tight correlation of the radio and MIR Luminosities of
starforming galaxies.


title: A two-stream formalism for the convective Urca process

abstract:
  We derive a new formalism for convective motions involving two radial flows.
This formalism provides a framework for convective models that guarantees
consistency for the chemistry and the energy budget in the flows, allows
time-dependence and accounts for the interaction of the convective motions with
the global contraction or expansion of the star. In the one-stream limit the
formalism reproduces several existing convective models and allows them to
treat the chemistry in the flows. We suggest a version of the formalism that
can be implemented easily in a stellar evolution code. We then apply the
formalism to convective Urca cores in Chandrasekhar mass white dwarfs and
compare it to previous studies. We demonstrate that, in degenerate matter,
nuclear reactions that change the number of electrons strongly influence the
convective velocities and we show that the net energy budget is sensitive to
the mixing. We illustrate our model by computing stationary convective cores
with Urca nuclei. Even a very small mass fraction of Urca nuclei (as little as
$10^{-8}$) strongly influences the convective velocities. We conclude that the
proper modelling of the Urca process is essential for determining the ignition
conditions for the thermonuclear runaway in Chandrasekhar-mass white dwarfs.


title: The convective Urca process

abstract:
  One possible fate of an accreting white dwarf is explosion in a type Ia
supernova. However, the route to the thermonuclear runaway has always been
uncertain owing to the lack of a convective model consistent with the Urca
process.
  We derive a formalism for convective motions involving two radial flows. This
formalism provides a framework for convective models that guarantees
self-consistency for chemistry and energy budget, allows time-dependence and
describes the interaction of convective motions with the global contraction or
expansion of the star. In the one-stream limit, we reproduce several already
existing convective models and allow them to treat chemistry. We also suggest
as a model easy to implement in a stellar evolution code.
  We apply this formalism to convective Urca cores in Chandrasekhar mass white
dwarfs. We stress that in degenerate matter, nuclear reactions that change the
number of electrons strongly influence the convective velocities. We point out
the sensitivity of the energy budget on the mixing. We illustrate our model by
computing {\it stationary} convective cores with Urca nuclei. We show that even
a very small mass fraction of Urca nuclei ($10^{-8}$) strongly influences the
convective velocities.
  Finally, we present preliminary computations of the late evolution of a close
to Chandrasekhar mass C+O white dwarf including the convective Urca process.


title: Quarks and Quakes

abstract:
  A quake model of bare strange stars for normal pulsar glitches is summarized.
Three mechanisms being responsible for developing elastic stress energy are
presented. It is suggested that other kinds of glitches (e.g, the frequency
glitch in KS 1947+300 and in AXP/SGRs) could represent the bulk-strain-induced
quakes. The apparent field increase of normal pulsars into ``magnetars'' could
be the result of stellar catastrophic shrinking when the elastic force raises
to a critical point.


title: Current Status of the SuperWASP Project

abstract:
  We present the current status of the SuperWASP project, a Wide Angle Search
for Planets. SuperWASP consists of up to 8 individual cameras using ultra-wide
field lenses backed by high-quality passively cooled CCDs. Each camera covers
7.8 x 7.8 sq degrees of sky, for nearly 500 sq degrees of sky coverage.
SuperWASP I, located in LaPalma, is currently operational with 5 cameras and is
conducting a photometric survey of a large numbers of stars in the magnitude
range ~7 to 15. The collaboration has developed a custom-built reduction
pipeline and aims to achieve better than 1 percent photometric precision. The
pipeline will also produce well sampled light curves for all the stars in each
field which will be used to detect: planetary transits, optical transients, and
track Near-Earth Objects. Status of current observations, and expected rates of
extrasolar planetary detections will be presented. The consortium members,
institutions, and further details can be found on the web site at:
http://www.superwasp.org.


title: Evolution of Cold Circumstellar Dust Around Solar-Type Stars

abstract:
  We present submillimeter (CSO 350um) and millimeter (SEST 1.2 mm, OVRO 3 mm)
photometry for 125 solar-type stars from the FEPS Spitzer Legacy program that
have masses between ~0.5 and 2.0 Msun and ages from 3 Myr to 3 Gyr. Continuum
emission was detected toward four stars with a signal to noise ratio >= 3$: the
classical T Tauri stars RX J1842.9-3532, RX J1852.3-3700, and PDS 66 with SEST,
and the debris disk system HD 107146 with OVRO. RXJ1842.9-3532 and
RXJ1852.3-3700 are located in projection nearby the R CrA molecular cloud with
estimated ages of ~10 Myr, while PDS66 is a probable member of the 20 Myr old
Lower Centaurus-Crux subgroup of the Sco-Cen OB association. The continuum
emission toward these three sources is unresolved at the 24'' SEST resolution
and likely originates from circumstellar accretion disks, each with estimated
dust masses of ~5x10**-5 Msun. Analysis of the visibility data toward HD107146
(age 80-200 Myr) indicates that the 3 mm continuum emission is centered on the
star within the astrometric uncertainties and resolved with a gaussian-fit FWHM
size of (6.5'' +/- 1.4'') x (4.2''+/-1.3''), or 185 AUx120 AU. The results from
our continuum survey are combined with published observations to quantify the
evolution of dust mass with time by comparing the mass distributions for
samples with different stellar ages. The frequency distribution of
circumstellar dust masses around solar-type stars in the Taurus molecular cloud
(age ~2 Myr) is distinguished from that around 3-10 Myr and 10-30 Myr old stars
at a significance level of ~1,5sigma and 3sigma respectively. These results
suggest a decrease in the mass of dust contained in small dust grains and/or
changes in the grain properties by stellar ages of 10-30 Myr, consistent with
previous conclusions. (abridged)


title: Disk-Like Structure in the Semi-Regular Pulsating Star, X Her

abstract:
  The author reports a result of an interferometric observation of the
semiragular pulsating star with an unusual narrow molecular line profile, X
Her, in the CO J=1-0 line with the Berkeley-Illinois-Maryland array. In the CO
spectrum, a double-component profile (including narrow and broad components) is
seen as reported by previous observations. The narrow component consists of two
spiky peaks. The spatial structure of the board component shows bipolar shape,
and that of the narrow component shows an elliptical/spherical shape. The two
peaks in the narrow component show a systematic difference in the integrated
intensity map. The kinematical and geometrical properties of the narrow
component are reminiscent of a Keplerian rotating disk with the central mass of
0.9 M_sun, though an interpretation by an expansion disk seems to be more
natural. A secondary bipolar flow instead of the disk cannot be fully excluded
as an interpretation of the narrow line.


title: Are Clusters as Indicators of the Cosmic Ray Anisotropy ?

abstract:
  The clusters (doublets) in ultrahigh energy cosmic rays are considered based
on Yakutsk and AGASA extensive air shower array data. The problem of cluster
origin is discussed. It is found that arrival directions of the clusters can
point to a cosmic ray anisotropy. As a result of analysis of clusters, the
conclusion on composition and origin of ultrahigh energy cosmic rays has been
made.


title:
Cooling of strange stars in the color-flavor locked phase with a
  rotating crust Cooling of strange stars in the color-flavor locked phase with
  a rotating crust

abstract:
  The presence of the color-flavor locked (CFL) phase strongly suppresses the
neutrino emission processes and the quark specific heat. As a result the
cooling of the strange stars in the CFL phase is dominated by deconfinement
heating and surface emission. The temperature of these stars with strong
magnetic field ($B{\geq}10^{10}G$) rise significantly during the first several
ten or hundred years, which may be an effective signature of strange stars as
implicated by pulsar 0540-69. Furthermore a limit line is predicted, which
means compact stars have an upper limit temperature at any moment. We still may
search for the candidates for strange stars in the CFL phase along the limit
line.
  The presence of the color-flavor locked (CFL) phase strongly suppresses the
neutrino emission processes and the quark specific heat. As a result the
cooling of the strange stars in the CFL phase is dominated by deconfinement
heating and surface emission. The temperature of these stars with strong
magnetic field ($B{\geq}10^{10}G$) rise significantly during the first several
ten or hundred years, which may be an effective signature of strange stars as
implicated by pulsar 0540-69. Furthermore a limit line is predicted, which
means compact stars have an upper limit temperature at any moment. We still may
search for the candidates for strange stars in the CFL phase along the limit
line.


title: Analytical light curves in the realistic model for GRB afterglows

abstract:
  (abridged) Afterglow light curves are constructed analytically for realistic
gamma-ray burst remnants decelerating in either a homogeneous interstellar
medium or a stellar wind environment, taking into account the radiative loss of
the blast wave, which affects the temporal behaviors significantly. Inverse
Compton scattering is considered. The inverse Compton effect prolongs the
fast-cooling phase markedly, during which the relativistic shock is
semi-radiative and the radiation efficiency is approximately constant. It is
further shown that the shock is still semi-radiative for quite a long time
after it transits into the slow-cooling phase. The temporal decaying index of
the X-ray afterglow light curve in this semi-radiative phase is more consistent
with the observed $<\alpha_{X}> \sim 1.3$ than the commonly used adiabatic one.
To manifest as a bump or even dominant in the X-ray afterglows during the
relativistic stage, it is required that the density should be larger than about
1-10 cm$^{-3}$ in the interstellar medium case, or the wind parameter
$A_{\ast}$ should be larger than unity in the stellar wind case.


title:
Neutrino-pair bremsstrahlung from nucleons in the condensed pion field:
  revisited

abstract:
  At temperatures less than a few MeV, the efficiency of the neutrino-pair
bremsstrahlung from nucleons interracting with the condensed pion field is much
less than previously estimated by other authors. The physical reason for this
is a periodic structure of the developed pion condensate. The repeated
interactions of a nucleon with the periodic pion field modify the nucleon
spectrum, which is split into two bands. The energy gap between the bands is
about a few MeV or larger, even if the amplitude of the pion field is small
compared with the pion mass.


title: Multicolor Surface Photometry of Lenticulars I. The Data

abstract:
  We present in this paper multicolor surface and aperture photometry in the B,
V, R and K' bands for a sample of 34 lenticular galaxies from the UGC
catalogue. From surface photometric analysis, we obtain radial profiles of
surface brightness, colors, ellipticity, position angle and the Fourier
coefficients which describe the departure of isophotal shapes from purely
elliptical form and find the presence of dust lanes, patches and ring like
structure in several galaxies in the sample. We obtain total integrated
magnitudes and colors and find that these are in good agreement with the values
from the RC3 catalogue. Isophotal colors are correlated with each other,
following the sequence expected for early-type galaxies. The color gradients in
lenticulars are more negative than the corresponding gradients in ellipticals.
There is a good correlation between B-V and B-R color gradients, and the mean
gradient in the B-V, B-R and V-K' colors are -0.13+/-0.06, -0.18+/-0.06,
-0.25+/-0.11 magnitude per dex in radius respectively.


title: Experimental Constraints on Self-consistent Reionization Models

abstract:
  A self-consistent formalism to jointly study cosmic reionization and thermal
history of the IGM is presented. The model implements most of the relevant
physics governing these processes, such as the inhomogeneous IGM density
distribution, three different sources of ionizing photons (PopIII stars, PopII
stars and QSOs), and radiative feedback. By constraining the free parameters
with available data on redshift evolution of Lyman-limit systems, Gunn-Peterson
and electron scattering optical depths, Near InfraRed Background (NIRB), and
cosmic star formation history, we select a fiducial model, whose main
predictions are: (i) H was completely reionized at z \approx 15, while HeII
must have been reionized by z \approx 12. At z \approx 7, HeIII suffered an
almost complete recombination as a result of the extinction of PopIII stars, as
required by the interpretation of the NIRB. (ii) A QSO-induced complete HeII
reionization occurs at z=3.5; a similar double H reionization does not take
place due to the large number of photons above 1 Ryd from PopII stars and QSOs,
even after PopIII stars have disappeared. (iii) Following reionization, the
temperature of the IGM corresponding to the mean gas density is boosted to
15000 K. Observations of T_0 are consistent with the fact that He is singly
ionized at z > 3.5, while they are consistent with He being doubly ionized at z
< 3.5. This might be interpreted as a signature of (second) HeII reionization.
(iv) Only 0.3% of the stars produced by z=2 need to be PopIII stars in order to
achieve the hydrogen reionization. Such model not only relieves the tension
between the Gunn-Peterson optical depth and WMAP observations, but also
accounts self-consistently for all known observational constraints (abridged).


title:
Non-linear shock acceleration and high energy gamma rays from clusters
  of galaxies

abstract:
  Merger and accretion shocks in clusters of galaxies can accelerate particles
via first order Fermi process. Since this mechanism is believed to be
intrinsically efficient, shocks are expected to be modified by the backreaction
of the accelerated particles. Such a modification might induce appreciable
effects on the non--thermal emission from clusters and a suppression of the
heating of the gas at strong shocks. Here we consider in particular the gamma
ray emission and we discuss the capability of Cherenkov telescopes such as HESS
to detect clusters at TeV energies.


title:
Two distinct ancient components in the Sculptor Dwarf Spheroidal Galaxy:
  First Results from DART

abstract:
  We have found evidence for the presence of two distinct ancient stellar
components (both geq 10 Gyr old) in the Sculptor dwarf spheroidal galaxy. We
used the ESO Wide Field Imager (WFI) in conjunction with the VLT/FLAMES
spectrograph to study the properties of the resolved stellar population of
Sculptor out to and beyond the tidal radius. We find that two components are
discernible in the spatial distribution of Horizontal Branch stars in our
imaging, and in the [Fe/H] and v_hel distributions for our large sample of
spectroscopic measurements. They can be generally described as a ``metal-poor''
component ([Fe/H]< -1.7) and a ``metal-rich'' component ([Fe/H]> -1.7). The
metal-poor stars are more spatially extended than the metal-rich stars, and
they also appear to be kinematically distinct. These results provide an
important insight into the formation processes of small systems in the early
universe and the conditions found there. Even this simplest of galaxies appears
to have had a surprisingly complex early evolution.


title: The Extreme Ends of the Metallicity Distribution in dSph Galaxies

abstract:
  This paper reviews recent abundance results of local dSph giants. All dSph
systems seem to show evidence of slow star formation rates, compared to the
Milky Way, based on the most metal-rich stars exhibiting low [even-Z/Fe] ratios
and high [s-process/r-process] ratios. The most metal-poor stars in the Draco,
Ursa Minor, Sextans and Sculptor dSphs seem to show a split in their light
even-Z, Mg and O, and the heavier even-Z, Ca and Ti, abundance ratios, where
the light even-Z are halo like and the heavier even-Z elements exhibit sub-halo
abundance ratios. This split remains a mystery. A review of the first dSph
abundance results from FLAMES+GIRAFFE on the VLT and HRS on the Hobby-Eberly
Telescope shows that the study of chemical evolution of dSph galaxies is
rapidly moving out of infancy and into an era requiring very large surveys
and/or targeted studies.


title: Magnetic turbulence in compressible fluids

abstract:
  We present high resolution numerical simulations of compressible
magnetohydrodynamic (MHD) turbulence. We concentrate on studies of spectra and
anisotropy of velocity and density. We describe a technique of separating
different magnetohydrodynamic (MHD) modes (slow, fast and Alfven) and apply it
to our simulations. For the mildly supersonic case, velocity and density show
anisotropy. However, for the highly supersonic case, we observe steepening of
the slow mode velocity spectrum and isotropization of density. Our present
studies show that the spectrum of density gets substantially
  {\it flatter} than the Kolmogorov one.


title:
The absorption spectrum of V838 Mon in 2002 February - March. I.
  Atmospheric parameters and iron abundance

abstract:
  We present a determination of the effective temperatures, iron abundances,
and microturbulent velocities for the pseudophotosphere of V838 Mon on 2002
February 25, and March 2 and 26. Physical parameters of the line forming region
were obtained in the framework of a self-consistent approach, using fits of
synthetic spectra to observed spectra in the wavelength range 5500-6700A. We
obtained Tef = 5330, 5540 and 4960 K, for February 25, March 2, and March 26,
respectively. The iron abundance log N(Fe)=-4.7 does not appear to change in
the atmosphere of V838 Mon from February 25 to March 26, 2002.


title: The coincidence problem in linear dark energy models

abstract:
  We show that a solution to the the coincidence problem can be found in the
context of a generic class of dark energy models with a scalar field, $\phi$,
with a linear effective potential $V(\phi)$. We determine the fraction, $f$, of
the total lifetime of the universe, $t_U$, which lies within the interval
$[t_0-\Delta t_A,t_0+ \Delta t_A]$, where $t_0$ is the age of the universe at
the present time, $\Delta t_A \equiv t_0-t_A$ and $t_A$ is the age of the
universe when it starts to accelerate. We find that if we require $f$ to be
larger than 0.1 (0.01) then $1+\omega_{\phi0} \gapp 2 \times 10^{-2}$ ($1
\times 10^{-3}$), where $\omega_{\phi} \equiv p_\phi/\rho_\phi$. These results
depend mainly on the linearity of the scalar field potential for $-V(\phi_0)
\lapp V(\phi) \lapp V(\phi_0)$ and are weakly dependent on the specific form of
$V(\phi)$ outside this range. We also show that if $\omega_{\phi0}$ is close to
-1 then $\omega_{\phi0}+1 \sim 1.6 ({\tilde \omega}_\phi +1)$, where ${\tilde
\omega}_\phi$ is the weighted average value of $\omega_{\phi}$ in the time
interval $[0,t_0]$. We independently confirm current observational constraints
on this class of models which give $\omega_{\phi0} \lapp -0.6$ and $t_U \gapp
2.4 t_0$ at the $2 \sigma$ level.


title: Has Dark Energy really been discovered in the Lab?

abstract:
  We show that Dark Energy contributions can not be determined from noise
measurements of Josephson junctions, as was recently suggested in a paper by C.
Beck and M.C. Mackey.


title:
The Impact of Small-Scale Structure on Cosmological Ionization Fronts
  and Reionization

abstract:
  The propagation of cosmological ionization fronts during the reionization of
the universe is strongly influenced by small-scale gas inhomogeneities due to
structure formation. These inhomogeneities include both collapsed minihalos,
which are generally self-shielding, and lower-density structures, which are
not. The minihalos are dense and sufficiently optically-thick to trap
intergalactic ionization fronts, blocking their path and robbing them of
ionizing photons until the minihalo gas is expelled as an evaporative wind. The
lower-density structures do not trap these fronts, but they can slow them down
by increasing the overall recombination rate in the intergalactic medium. In
this paper we study the effects of both types of inhomogeneities, including
nonlinear clustering effects, and we find that both IGM clumping and collapsed
minihalos have significant yet qualitatively different impacts on reionization.
While the number density of minihalos on average increases strongly with time,
the density of minihalos inside H II regions around ionizing sources is largely
constant. Thus the impact of minihalos is essentially to decrease the number of
ionizing photons available to the IGM at all epochs, which is equivalent to a
reduction in the luminosity of each source. On the other hand, the effect of
IGM clumping increases strongly with time, slowing down reionization and
extending it. Thus while the impact of minihalos is largely degenerate with the
unknown source efficiency, IGM clumping can help significantly in reconciling
the recent observations of cosmic microwave background polarization with quasar
absorption spectra at z~6, which together point to an early but extended
reionization epoch.


title: Swift Identification of Dark Gamma-Ray Bursts

abstract:
  We present an optical flux vs. X-ray flux diagram for all known gamma-ray
bursts (GRBs) for which an X-ray afterglow has been detected. We propose an
operational definition of dark bursts as those bursts that are optically
subluminous with respect to the fireball model, i.e., which have an
optical-to-X-ray spectral index beta_OX < 0.5. Out of a sample of 52 GRBs we
identify 5 dark bursts. The definition and diagram serve as a simple and quick
diagnostic tool for identifying dark GRBs based on limited information,
particularly useful for early and objective identification of dark GRBs
observed with the Swift satellite.


title:
The scale-dependence of relative galaxy bias: encouragement for the halo
  model description

abstract:
  We investigate the relationship between the colors, luminosities, and
environments of galaxies in the Sloan Digital Sky Survey spectroscopic sample,
using environmental measurements on scales ranging from 0.2 to 6 Mpc/h. We
find: (1) that the relationship between color and environment persists even to
the lowest luminosities we probe (absolute magnitude in the r band of about -14
for h=1); (2) at luminosities and colors for which the galaxy correlation
function has a large amplitude, it also has a steep slope; and (3) in regions
of a given overdensity on small scales (1 Mpc/h), the overdensity on large
scales (6 Mpc/h) does not appear to relate to the recent star formation history
of the galaxies. Of these results, the last has the most immediate application
to galaxy formation theory. In particular, it lends support to the notion that
a galaxy's properties are related only to the mass of its host dark matter
halo, and not to the larger scale environment.


title:
Constraining Reionization with the Evolution of the Luminosity Function
  of Lyman Alpha mitting Galaxies

abstract:
  At redshifts beyond z>6, as the mean fraction of neutral hydrogen x_HI in the
intergalactic medium (IGM) increases, the line flux of Lyman alpha (Lya)
emitters can be significantly suppressed, which can result in a decrease in the
observed number of emitters at a given Lya flux. However, cosmological HII
regions surrounding the Lya emitting galaxies alleviate these effects. We use
simple models of the Lya line suppression that incorporate the presence of HII
regions to predict the overall effect of the Lya absorption on the Lya
luminosity function. We find, in agreement with other recent studies, that
unless ionizing sources are unusually strongly clustered, a fully neutral IGM
may be inconsistent with the large abundance of confirmed z=6.5 Lya emitters.
However, the presence of local HII regions prohibits placing a tight constraint
on the mean neutral fraction. We find x_HI < 0.25; the presence of strong winds
and/or the clustering of ionizing sources would further weaken this constraint.
We conclude that the evolution of the Lya LF is consistent with reionization
occurring near this redshift. Finally, we suggest that a measurement of
observed Lya line width as a function of the Lya luminosity, in a future,
larger sample of Lya emitters, may serve as a robust diagnostic of the neutral
fraction in the IGM.


title:
Generalized Chaplygin gas as a unified scenario of dark matter/energy:
  observational constraints

abstract:
  Although various cosmological observations congruously suggest that our
universe is dominated by two dark components, the cold dark matter without
pressure and the dark energy with negative pressure, the nature and origin of
these components is yet unknow. The generalized Chaplygin gas (gCg),
parametrized by an equation of state, $p = -A/\rho_{\rm gCg}^{\alpha}$, was
recently proposed to be a candidate of the unified dark matter/energy (UDME)
scenarios. In this work, we investigate some observational constraints on it.
We mainly focus our attention on the constraints from recent measurements of
the X-ray gas mass fractions in clusters of galaxies published by Allen et al.
(2002,2003) and the dimensionless coordinate distances to type Ia supernovae
and Fanaroff-Riley type IIb radio galaxies compiled by Daly and Djorgovski
(2003). We obtain the confidence region on the two parameters fully
characterizing gCg, $A_s \equiv A/\rho_{{\rm gCg}0}^{(1+\alpha)}$ and $\alpha$,
from a combined analysis of these databases, where $\rho_{{\rm gCg}0}$ is the
energy density of gCg at present. It is found that $A_s=0.70^{+0.16}_{-0.17}$
and $\alpha=-0.09^{+0.54}_{-0.33}$, at a 95% confidence level, which is
consistent within the errors with the standard dark matter + dark energy model,
i.e., the case of $\alpha = 0$. Particularly, the standard Chaplygin gas
($\alpha=1$) is ruled out as a feasible UDME by the data at a 99% confidence
level.


title: Ultra-Luminous Sources in Nearby Galaxies

abstract:
  I briefly review much of the X-ray and optical data on the nature of the ULXs
in nearby galaxies. I present new results on radio emission, finding that the
radio is usually rather luminous and extended. I review the X-ray data on
timing and spectra. There is no direct evidence in the X-ray data for either
geometric or relativistic beaming and in 4 objects direct evidence against
beaming. I argue that the X-ray timing and spectral properties of these objects
are, in general, not good analogs of AGN or galactic black holes and that the
ULX may represent a new mode of accretion only rarely seen in other objects.


title:
Abundance Ratios in the Galactic Bulge and Super Metal-Rich Type II
  Nucle osynthesis

abstract:
  We present abundance results from our Keck/HIRES observations of giants in
the Galactic Bulge. We confirm that the metallicity distribution of giants in
the low-reddening bulge field Baade's Window can be well-fit by a closed-box
enrichment model. We also confirm previous observations that find enhanced
[Mg/Fe], [Si/Fe] and [Ca/Fe] for all bulge giants, including those at
super-solar metallicities. However, we find that the [O/Fe] ratios of
metal-rich bulge dwarfs decrease with increasing metallicity, contrary to what
is expected if the enhancements of the other $\alpha$-elements is due to Type
II supernovae enrichment. We suggest that the decrease in oxygen production may
be due to mass loss in the pre-supernova evolution of metal-rich progenitors.


title:
X-ray Emission Properties of Large Scale Jets, Hotspots and Lobes in
  Active Galactic Nuclei

abstract:
  We examine a systematic comparison of jet-knots, hotspots and radio lobes
recently observed with Chandra and ASCA. This report will discuss the origin of
their X-ray emissions and investigate the dynamics of the jets. The data was
compiled at well sampled radio (5GHz) and X-ray frequencies (1keV) for more
than 40 radio galaxies. We examined three models for the X-ray production:
synchrotron (SYN), synchrotron self-Compton (SSC) and external Compton on CMB
photons (EC). For the SYN sources -- mostly jet-knots in nearby low-luminosity
radio galaxies -- X-ray photons are produced by ultrarelativistic electrons
with energies 10-100 TeV that must be accelerated in situ. For the other
objects, conservatively classified as SSC or EC sources, a simple formulation
of calculating the ``expected'' X-ray fluxes under an equipartition hypothesis
is presented. We confirmed that the observed X-ray fluxes are close to the
expected ones for non-relativistic emitting plasma velocities in the case of
radio lobes and majority of hotspots, whereas considerable fraction of
jet-knots is too bright at X-rays to be explained in this way. We examined two
possibilities to account for the discrepancy in a framework of the
inverse-Compton model: (1) magnetic field is much smaller than the
equipartition value, and (2) the jets are highly relativistic on kpc/Mpc
scales. We concluded, that if the inverse-Compton model is the case, the X-ray
bright jet-knots are most likely far from the minimum-power condition. We also
briefly discuss the other possibility, namely that the observed X-ray emission
from all of the jet-knots is synchrotron in origin.


title: Cosmological N-Body simulation: Techniques, Scope and Status

abstract:
  Cosmological N-Body simulations have become an essential tool for studying
formation of large scale structure. These simulations are computationally
challenging even though the available computing power gets better every year. A
number of efficient algorithms have been developed to run large simulations
with better dynamic range and resolution. We discuss key algorithms in this
review, focusing on techniques used and their efficacy. N-Body simulations
solve a model that is an approximation of the physical model to be simulated,
we discuss limitations arising from this approximation and techniques employed
for solving equations. Apart from simulating models of structure formation,
N-Body simulations have also been used to study aspects of gravitational
clustering. Simulating formation of galaxies requires us to take many physical
process into account; we review numerical implementations of key processes.


title: Dark Energy: the Cosmological Challenge of the Millennium

abstract:
  Recent cosmological observations suggest that nearly seventy per cent of the
energy density in the universe is unclustered and has negative pressure.
Several conceptual issues related to the modeling of this component (`dark
energy'), which is driving an accelerated expansion of the universe, are
discussed with special emphasis on the cosmological constant as the possible
choice for the dark energy. Some curious geometrical features of a universe
with a cosmological constant are described and a few attempts to understand the
nature of the cosmological constant are reviewed.


title: Faraday Rotation Measures through the Cores of Southern Galaxy Clusters

abstract:
  We present a study of the rotation measure (RM) obtained from a sample of
extra-galactic radio sources either embedded in or seen in projection through a
sample of seven southern galaxy clusters (declination less than 30 degrees). We
compare our results with those obtained previously through similar statistical
studies and conclude there is a statistically significant broadening of the RM
signal in galaxy clusters when compared to a control sample. Further, we concur
with the findings of Clarke (2000) that the typical influence of the cluster on
the RM extends to around 800 kpc from the cluster core and that the RMs
determined are on average consistent with a 1-2 micro G field.


title:
Radiative Feedback from Quasars and the Growth of Supermassive Black
  Holes

abstract:
  We discuss the role of feedback via photoionization and Compton heating in
the co-evolution of massive black holes at the center of spheroidal galaxies
and their stellar and gaseous components. We first assess the energetics of the
radiative feedback from a typical quasar on the ambient interstellar gas. We
then demonstrate that the observed Mbh-sigma relation could be established at a
relatively early epoch in galactic evolution when the formation of the stellar
bulge was almost completed and the gas-to-stars mass ratio was reduced to a low
level ~0.01 such that cooling could not keep up with radiative heating. A
considerable amount of gas was expelled at that time and black hole accretion
proceeded at a much lower rate thereafter.


title:
Search for the elusive optical counterpart of PSR J0537-6910 with the
  HST Advanced Camera for Surveys

abstract:
  We present the results of deep, high-resolution, multi-band optical
observations of the field of the young (~ 5,000 yrs) 16 ms X-ray pulsar PSR
J0537$-$6910 performed with the Advanced Camera for Surveys (ACS) aboard the
Hubble Space Telescope (HST). Although a few new potential counterparts have
been detected within or close to the revised Chandra X-ray error circle (~1
arcsec) of the pulsar, only two of them (with magnitudes m_{814W} ~ 23.9 and
m_{814W} ~ 24.2) show indications of a peculiar spectrum which could be related
to optical emission from the pulsar. This might be true also for a third,
fainter, candidate detected only in one filter (with magnitude m_{814W} ~
26.7). If either of the two brighter candidates is indeed the actual
counterpart, the optical output of PSR J0537-6910 would make it similar to
young Crab-like pulsars. If not, it would mean that PSR J0537-6910 is
significantly underluminous with respect to all pulsars detected in the optical


title: Nature of a Strongly-Lensed Submillimeter Galaxy SMM J14011+0252

abstract:
  We have carried out near-infrared JHK spectroscopy of a gravitationally
lensed submillimeter galaxy SMM J14011+0252 at z=2.565, using OHS and CISCO on
the Subaru telescope. This object consists of two optical components, J1 and
J2, which are lensed by the cluster Abell 1835. J1 suffers additional strong
lensing by a foreground galaxy at z=0.25 in the cluster. The rest-optical
H-alpha, H-beta, and [O II]3727 lines are detected in both J1 and J2, and [N
II]6548,6583 lines are also detected in J1. A diagnosis of emission-line ratios
shows that the excitation source of J1 is stellar origin, consistent with
previous X-ray observations. The continua of J1 and J2 show breaks at rest
4000A, indicating relatively young age. Combined with optical photometry, we
have carried out model spectrum fitting of J2 and find that it is a very young
(~50 Myr) galaxy of rather small mass (~10e8 M_sol) which suffers some amount
of dust extinction. A new gravitational lensing model is constructed to assess
both magnification factor and contamination from the lensing galaxy of the
component J1, using HST-F702W image. We have found that J1 suffers strong
lensing with magnification of ~30, and its stellar mass is estimated to be <
10e9 M_sol. These results suggest that SMM J14011+0252 is a major merger system
at high redshift that undergoes intense star formation, but not a formation
site of a giant elliptical. Still having plenty of gas, it will transform most
of the gas into stars and will evolve into a galaxy of < 10e10 M_sol.
Therefore, this system is possibly an ancestor of a less massive galaxy such as
a mid-sized elliptical or a spiral at the present.


title: The Physics of CMBR Anisotropies

abstract:
  The observed structures in the universe are thought to have arisen from
gravitational instability acting on small fluctuations generated in the early
universe. These spatial fluctuations are imprinted on the CMBR as angular
anisotropies. The physics which connects initial fluctuations in the early
universe to the observed anisotropies is fairly well understood, since for most
part it involves linear perturbation theory. This makes CMBR anisotropies one
of the cleanest probes of the initial fluctuations, various cosmological
parameters governing their evolution and also the geometry of the universe. We
review here in a fairly pedagogical manner the physics of the CMBR anisotropies
and explain the role they play in probing cosmological parameters, especially
in the light of the latest observations from the WMAP satellite.


title: High Redshift Intergalactic Medium: Probes and Physical Models

abstract:
  Recent years have seen major advances in understanding the state of the
intergalactic medium (IGM) at high redshift. Some aspects of this understanding
are reviewed here. In particular, we discuss: (1) Different probes of IGM like
Gunn-Peterson test, CMBR anisotropies, and neutral hydrogen emission from
reionization, and (2) some models of reionization of the universe.


title: The XMM-Newton view of PG quasars I. X-ray continuum and absorption

abstract:
  We present results of a systematic analysis of the XMM-Newton spectra of 40
quasars (QSOs) (z<1.72) from the Palomar-Green (PG) Bright Quasar Survey sample
(M_B<-23). The sample includes 35 radio-quiet quasars (RQQs) and 5 radio-loud
quasars (RLQs). The analysis of the spectra above 2 keV reveals that the hard
X-ray continuum emission can be modeled with a power law component with
<Gamma_(2-12)> = 1.89+/-0.11 and <Gamma_(2-12)> = 1.63^(+0.02)_(-0.01) for the
RQQs and RLQs, respectively. Below 2 keV, a strong, broad excess is present in
most QSO spectra. This feature has been fitted with four different models
assuming several physical scenarios. All tested models (blackbody, multicolor
blackbody, bremsstrahlung and power law) satisfactorily fitted the majority of
the spectra. However, none of them is able to provide an adequate
parameterization for the soft excess emission in all QSOs, indicating the
absence of an universal shape for this spectral feature. An additional cold
absorption component was required only in three sources. On the other hand, as
recently pointed out by Porquet et al. (2004) for a smaller sample of PG QSOs,
warm absorber features are present in ~50% of the QSO spectra in contrast with
their rare occurrence (~5-10%) found in previous studies. The XMM-Newton view
of optically-selected bright QSOs therefore suggests that there are no
significant difference in the X-ray spectral properties once compared with the
low-luminosity Seyfert 1 galaxies. Properties of the Fe Kalpha emission lines
are presented in a companion paper.


title: Oscillating neutron star as a pulsar

abstract:
  Pulsar "standard model" of rotating magnetized conducting sphere surrounded
by plasma is generalized in its essential parts for the case of oscillating
star. Goldreich-Julian charge density, electromagnetic energy losses as well as
polar cap scenario of particle accelerations are considered. Despite
similarities, there are substantial differences between magnetospheres of
rotating and oscillating stars. Distortion of particle acceleration mechanism
in radiopulsars by neutron star oscillations, excited by a strong glitch, for
example, is discussed.


title: The White Dwarfs in AM CVn systems - candidates for SN Ia?

abstract:
  Thanks to the rapid increase of observations of Supernovae Ia, we may now
claim that the Universe is accelerating. SN Ia are believed to be good standard
candles, and after correcting the observations by various methods a precise
Hubble diagram results. One of the most important problems to solve in
astrophysics today is to find the progenitors of SN Ia. Candidates are to be
found in close binary systems where one of the components may accumulate
Chandrasekhar mass and then explode. We show that the AM CVn systems may
contribute to the SNe population, but will not be the dominant contributor.


title:
Orbital parameters, masses and distance to Beta Centauri determined with
  the Sydney University Stellar Interferometer and high resolution spectroscopy

abstract:
  The bright southern binary star beta Centauri (HR 5267) has been observed
with the Sydney University Stellar Interferometer (SUSI) and spectroscopically
with the ESO CAT and Swiss Euler telescopes at La Silla. The interferometric
observations have confirmed the binary nature of the primary component and have
enabled the determination of the orbital parameters of the system. At the
observing wavelength of 442 nm the two components of the binary system have a
magnitude difference of 0.15. The combination of interferometric and
spectroscopic data gives the following results: orbital period 357 days,
semi-major axis 25.30 mas, inclination 67.4 degrees, eccentricity 0.821,
distance 102.3 pc, primary and secondary masses M1 = M2 = 9.1 solar masses and
absolute visual magnitudes of the primary and secondary M1V = -3.85 and M2V =
-3.70. The high accuracy of the results offers a fruitful starting point for
future asteroseismic modelling of the pulsating binary components.


title: Gas accretion in galactic disks

abstract:
  Evidence for the accretion of material in spiral galaxies has grown over the
past years and clear signatures can be found in HI observations of galaxies.
  We describe here new detailed and sensitive HI synthesis observations of a
few nearby galaxies (NGC 3359, NGC 4565 and NGC 6946) which show that indeed
accretion of small amounts of gas is taking place.
  These should be regarded as examples illustrating a general phenomenon of gas
infall in galaxies. Such accretion may also be at the origin of the gaseous
halos which are being found around spirals. Probably it is the same kind of
phenomenon of material infall as observed in the stellar streams in the halo
and outer parts of our galaxy and M 31


title: Particle Acceleration at shocks: some modern aspects of an old problem

abstract:
  The acceleration of charged particles at astrophysical collisionless shock
waves is one of the best studied processes for the energization of particles to
ultrarelativistic energies, required by multifrequency observations in a
variety of astrophysical situations. In this paper we discuss some work aimed
at describing one of the main progresses made in the theory of shock
acceleration, namely the introduction of the non-linear backreaction of the
accelerated particles onto the shocked fluid. The implications for the
investigation of the origin of ultra high energy cosmic rays will be discussed.


title: Abundances and ages of the deconvolved thin/thick disks of the Galaxy

abstract:
  We have investigated the abundance of several chemical elements in two large
stellar samples kinematically representative of the thin and the thick disks of
the Galaxy. Chemical, kinematical and age data have been collected from high
quality sources in the literature. Velocities (U,V,W) have been computed and
used to select stars with the highest probability to belong to the thin disk
and the thick disk respectively. Our results show that the two disks are
chemically well separated. Both exhibit a decline of [$\alpha$/Fe] with
increasing [Fe/H]. A transition between the thin/thick disks stars is observed
at 10 Gyr.


title: From gas to galaxies

abstract:
  The unsurpassed sensitivity and resolution of the Square Kilometer Array
(SKA) will make it possible for the first time to probe the continuum emission
of normal star forming galaxies out to the edges of the universe. This opens
the possibility for routinely using the radio continuum emission from galaxies
for cosmological research as it offers an independent probe of the evolution of
the star formation density in the universe. In addition it offers the
possibility to detect the first star forming objects and massive black holes.
  In deep surveys SKA will be able to detect HI in emission out to redshifts of
$z \approx 2.5$ and hence be able to trace the conversion of gas into stars
over an era where considerable evolution is taking place. Such surveys will be
able to uniquely determine the respective importance of merging and accreting
gas flows for galaxy formation over this redshift range (i.e. out to when the
universe was only one third its present age). It is obvious that only SKA will
able to see literally where and how gas is turned into stars.
  These and other aspects of SKA imaging of galaxies will be discussed.


title: The diversity of Type Ia Supernovae: evidence for systematics?

abstract:
  The photometric and spectroscopic properties of 26 well observed Type Ia
Supernovae (SNeIa) were analyzed with the aim to explore SNIa diversity. The
sample includes (Branch-)normal SNe as well as extreme events like SNe 1991T
and 1991bg, while the truly peculiar SNIa, SN2000cx and SN2002cx are not
included in our sample . A statistical treatment reveals the existence of three
different groups. The first group (FAINT) consists of faint SNeIa similar to
SN1991bg, with low expansion velocities and rapid evolution of SiII velocity. A
second group consists of ``normal'' SNeIa, also with high temporal velocity
gradient (HVG), but with brighter mean absolute magnitude <M_B>=-19.3 and
higher expansion velocities than the FAINT SNe. The third group includes both
``normal'' and SN1991T-like SNeIa: these SNe populate a narrow strip in the
SiII velocity evolution plot, with a small velocity gradient (SVG), but have
absolute magnitudes similar to HVGs. While the FAINT and HVG SNeIa together
seem to define a relation between RSi(II) and Dm15(B), the SVG ones either do
not conform with that relation or define a new, looser one. The RSi(II)
pre-maximum evolution of HVGs is strikingly different from that of SVGs. The
impact of this evidence on the understanding of SNIa diversity, in terms of
explosion mechanisms, degree of ejecta mixing, and ejecta-CSM interaction, is
discussed.


title: On a possible photon origin of the most-energetic AGASA events

abstract:
  In this work the ultra high energy cosmic ray events recorded by the AGASA
experiment are analysed. With detailed simulations of the extensive air showers
initiated by photons, the probabilities are determined of the photonic origin
of the 6 AGASA events for which the muon densities were measured and the
reconstructed energies exceeded 10^20 eV. On this basis a new, preliminary
upper limit on the photon fraction in cosmic rays above 10^20 eV is derived and
compared to the predictions of exemplary top-down cosmic-ray origin models.


title: Sub-millimeter images of a dusty Kuiper belt around eta Corvi

abstract:
  We present sub-millimeter and mid-infrared images of the circumstellar disk
around the nearby F2V star eta Corvi. The disk is resolved at 850um with a size
of ~100AU. At 450um the emission is found to be extended at all position
angles, with significant elongation along a position angle of 130+-10deg; at
the highest resolution (9.3") this emission is resolved into two peaks which
are to within the uncertainties offset symmetrically from the star at 100AU
projected separation. Modeling the appearance of emission from a narrow ring in
the sub-mm images shows the observed structure cannot be caused by an edge-on
or face-on axisymmetric ring; the observations are consistent with a ring of
radius 150+-20AU seen at 45+-25deg inclination. More face-on orientations are
possible if the dust distribution includes two clumps similar to Vega; we show
how such a clumpy structure could arise from the migration over 25Myr of a
Neptune mass planet from 80-105AU. The inner 100AU of the system appears
relatively empty of sub-mm emitting dust, indicating that this region may have
been cleared by the formation of planets, but the disk emission spectrum shows
that IRAS detected an additional hot component with a characteristic
temperature of 370+-60K (implying a distance of 1-2AU). At 11.9um we found the
emission to be unresolved with no background sources which could be
contaminating the fluxes measured by IRAS. The age of this star is estimated to
be ~1Gyr. It is very unusual for such an old main sequence star to exhibit
significant mid-IR emission. The proximity of this source makes it a perfect
candidate for further study from optical to mm wavelengths to determine the
distribution of its dust.


title: Gravitational collapse of polytropic, magnetized, filamentary clouds

abstract:
  When the gas of a magnetized filamentary cloud obeys a polytropic equation of
state, gravitational collapse of the cloud is studied using a simplified model.
We concentrate on the radial distribution and restrict ourselves to the purely
toroidal magnetic field. If the axial motions and poloidal magnetic fields are
sufficiently weak, we could reasonably expect our solutions to be a good
approximation. We show that while the filament experiences gravitational
condensation and the density at the center increases, the toroidal flux-to-mass
ratio remains constant. A series of spatial profiles of density, velocity and
magnetic field for several values of the toroidal flux-to-mass ratio and the
polytropic index, is obtained numerically and discussed.


title:
ISO observations of 3 - 200 micron emission by three dust populations in
  an isolated local translucent cloud

abstract:
  We present ISOPHOT spectrophotometry of three positions within the isolated
high latitude cirrus cloud G 300.2 - 16.8, spanning from the near- to
far-infrared. The positions exhibit contrasting emission spectrum contributions
from the UIBs, very small grains and large classical grains, and both
semi-empirical and numerical models are presented. At all three positions, the
UIB spectrum shapes are found to be similar, and the large grain emission may
be fitted by an equilibrium temperature of ~17.5 K. The energy requirements of
both the observed emission spectrum and optical scattered light are shown to be
satisfied by the incident local ISRF. The FIR emissivity of dust in G 300.2 -
16.8 is found to be lower than in globules or dense clouds, and is even lower
than model predictions for dust in the diffuse ISM. The results suggest
physical differences in the ISM mixtures between positions within the cloud,
possibly arising from grain coagulation processes.


title: Recent Advances in X-ray Observations of Cataclysmic Variables

abstract:
  A personal selection of noteworthy X-ray results on CVs are presented, with
emphasis on XMM-Newton and Chandra observations. Progressing roughly from
broad-band view to narrow-band, high spectral resolution studies, I summarize:
the energy balance of polars; X-ray confirmation of IPs; eclipses in
non-magnetic CVs; search for magnetism in "non-magnetic" CVs; multi-temperature
plasma emission from the boundary layer; complex absorption in magnetic CVs;
temperature and density diagnostics; and X-ray radial velocity studies.


title: A Survey of OVI Absorption in the Local Interstellar Medium

abstract:
  We report the results of a survey of OVI 1032 absorption along the lines of
sight to 25 white dwarfs in the local interstellar medium (LISM) obtained with
the Far Ultraviolet Spectroscopic Explorer (FUSE). We find that interstellar
OVI absorption along all sightlines is generally weak, and in a number of
cases, completely absent. No OVI absorption was detected with significance
greater than 2 sigma for 12 of the 25 stars, where the 1 sigma uncertainty is 4
mA, equivalent to an OVI column density of ~3 x 10^12 cm^-2. Of the remaining
stars, most have column densities N(OVI) < 10^13 cm^-2 and no column densities
exceed 1.7 x 10^13 cm^-2. For lines of sight to hot (T_eff > 40,000 K) white
dwarfs, there is some evidence that the OVI absorption may be at least
partially photospheric or circumstellar in origin. We interpret the "patchy"
distribution of OVI absorption in terms of a model where OVI is formed in
evaporative interfaces between cool clouds and the hot, diffuse gas in the
Local Bubble (LB). If the clouds contain tangled or tangential magnetic fields,
then thermal conduction will be quenched over most of the cloud surface, and
OVI will be formed only in local "patches" where conduction is allowed to
operate. We find an average OVI space density in the LISM of 2.4 x 10^-8 cm^-3,
which is similar to, or slightly larger than, the value in the Galactic disk
over kpc scales. This local density implies an average OVI column density of ~7
x 10^12 cm^-2 over a path length of 100 pc within the LB. The OVI data
presented here appears to be inconsistent with the model proposed by
Breitschwerdt & Schmutzler (1994), in which highly ionized gas at low kinetic
temperature (~50,000 K) permeates the LB. Our survey results are consistent
with the supernova-driven cavity picture of Cox & Smith (1974).


title: Jet-Disc coupling in the accreting black hole XTEJ1118+480

abstract:
  We interpret the rapid correlated UV/optical/ X-ray variability of
XTEJ1118+480 as a signature of the coupling between the X-ray corona and a jet
emitting synchrotron radiation in the optical band.We propose a scenario in
which the jet and the X-ray corona are fed by the same energy reservoir where
large amounts of accretion power are stored before being channelled into either
the jet or the high energy radiation. This time dependent model reproduces the
main features of the rapid multi-wavelength variability of XTEJ1118+480. A
strong requirement of the model is that the total jet power should be at least
a few times larger than the observed X-ray luminosity. This would be consistent
with the overall low radiative efficiency of the source. We present independent
arguments showing that the jet probably dominates the energetic output of all
accreting black holes in the low-hard state.


title:
The SCUBA Local Universe Galaxy Survey: Results from the
  Optically-Selected Sample

abstract:
  We present new results from the SCUBA Local Universe Galaxy Survey, the first
large statistical submillimetre survey of the local Universe. Following our
initial survey of a sample of 104 IRAS-selected galaxies we now present the
results of a sample of 80 Optically-selected galaxies. Since SCUBA is sensitive
to the large proportion of dust too cold to be detected by IRAS the addition of
this Optically-selected sample allows us for the first time to determine the
amount of cold dust in galaxies of different Hubble types. We detect 6
ellipticals in the sample and find them to have dust masses in excess of 10^7
solar masses. We derive local submillimetre Luminosity Functions and Dust Mass
functions, both directly for the Optically-Selected SLUGS sample and by
extrapolation from the IRAS PSCz survey, and find them to be well-fitted by
Schechter functions. We find excellent agreement between the two LFs and DMFs
and show that, whereas the slope of the IRAS-selected LF at lower luminosities
was steeper than -2 (a submm "Olbers' Paradox"), as expected the
PSCz-extrapolated LF flattens out at the low luminosity end.


title: Large-scale inhomogeneities in modified Chaplygin gas cosmologies

abstract:
  We extend the homogeneous modified Chaplygin cosmologies to large-scale
perturbations by formulating a Zeldovich-like approximation. We show that the
model interpolates between an epoch with a soft equation of state and a de
Sitter phase, and that in the intermediate regime its matter content is simply
the sum of dust and a cosmological constant. We then study how the large-scale
inhomogeneities evolve and compare the results with cold dark matter (CDM),
$\Lambda$CDM and generalized Chaplygin scenarios. Interestingly, we find that
unlike the latter, our models do always resemble $\Lambda$CDM.


title: Integral observation of Cyg X-1 in an intermediate state

abstract:
  We present preliminary results of an observation of Cygnus X-1 with INTEGRAL
performed on June 7-11 2003.
  Both spectral and variability properties of the source indicate that Cygnus
X-1 was in an intermediate state. As expected during state transitions, we find
an anticorrelation between the 3-10 keV and the 15 GHz radio fluxes and a
strong correlation between the 3-200 keV hardness and radio flux.


title:
Globular Clusters as Tracers of Stellar Bimodality in Elliptical
  Galaxies: The Case of NGC 1399

abstract:
  Globular cluster systems (GCS) frequently show a bi-modal distribution of the
cluster integrated colours. This work explores the arguments to support the
idea that the same feature is shared by the diffuse stellar population of the
galaxy they are associated with. In the particular case of NGC 1399 the results
show that the galaxy brightness profile and colour gradient as well as the
behaviour of the cumulative globular cluster specific frequency, are compatible
with the presence of two dominant stellar populations, associated with the so
called "blue" and "red" globular cluster families. These globular families are
characterized by different intrinsic specific frequencies (defined in terms of
each stellar population): Sn=3.3 +/- 0.3 in the case of the red globulars and
Sn=14.3 +/- 2.5 for the blue ones. We stress that this result is not
necessarily conflicting with recent works that point out a clear difference
between the metallicity distribution of (resolved) halo stars and globulars
when comparing their number statistics. The inferred specific frequencies imply
that, in terms of their associated stellar populations, the formation of the
blue globulars took place with an efficiency about 6 times higher than that
corresponding to their red counterparts. The similarity of the spatial
distribution of the blue globulars with that inferred for dark matter, as well
as with that of the X ray emiting hot gas associated with NGC 1399, is
emphasized. The impact of a relatively unconspicuous low metallicity
population, that shares the properties of the blue globulars, as a possible
source of chemical enrichment early in the formation history of the galaxy is
also briefly discussed.


title:
Origins of the ALMA Project in the scientific visions of the North
  American, European, and Japanese astronomical communities

abstract:
  ALMA is a worldwide project, the synthesis of early visions of astronomers in
its three partner communities, Europe, North America, and Japan. The evolution
of these concepts and their eventual merger into ALMA are discussed, setting
the background for the papers which follow on the scientific requirements and
expected performance of ALMA for extra-galactic, galactic, and solar system
research.