title: C II Radiative Cooling of the Diffuse Gas in the Milky Way

abstract:
  The heating and cooling of the interstellar medium allow the gas in the ISM
to coexist at very different temperatures in thermal pressure equilibrium. The
heating cannot be directly determined, but the cooling can be inferred from
observations of C II*, which is an important coolant in different environments.
The amount of cooling can be measured through either the intensity of the 157.7
\micron [C II] emission line or the C II* absorption lines at 1037.018 \AA\ and
1335.708 \AA, observable with FUSE and HST/STIS, respectively. We present the
results of a survey of these far-UV absorption lines in 43 objects situated at
|b|>30. We derive the cooling rates and analyze the ionization structure, the
depletion, and metallicity content from the column densities of C II*, S II, P
II, Fe II, and H I 21-cm emission for the low-, intermediate-, and
high-velocity clouds (LVCs, IVCs, and HVCs) along the different sightlines.
Based on the depletion and the ionization structure, the LVCs, IVCs, and HVCs
consist mostly of warm neutral and ionized clouds. For the LVCs, the mean
cooling rate in erg\,s^{-1} per H atom is -25.70^{+0.19}_{-0.36} dex. The
corresponding total Galactic C II luminosity in the 157.7 \micron emission line
is L~2.6x10^7 L_\sun. Combining N(C II*) with the intensity of H$\alpha$
emission, we derive that ~50% of the C II* radiative cooling comes from the
warm ionized medium (WIM). The large dispersion in the cooling rates is
certainly due to a combination of differences in the ionization fraction, in
the dust-to-gas fraction, and physical conditions between sightlines. For the
IVC IV Arch at z~1 kpc we find that on average the cooling is a factor 2 lower
than in the LVCs that probe gas at lower z. For an HVC (Complex C, at z > 6
kpc) we find the much lower rate of -26.99^{+0.21}_{-0.53} dex. [Abridged]


title: The essence of quintessence and the cost of compression

abstract:
  Standard two-parameter compressions of the infinite dimensional dark energy
model space show crippling limitations even with current SN-Ia data. Firstly
they cannot cope with rapid evolution - the best-fit to the latest SN-Ia data
shows late and very rapid evolution to w_0 = -2.85. However all of the standard
parametrisations (incorrectly) claim that this best-fit is ruled out at more
than 2-sigma, primarily because they track it well only at very low redshifts,
z < 0.2. Further they incorrectly rule out the observationally acceptable
region w << -1 for z > 1. Secondly the parametrisations give wildly different
estimates for the redshift of acceleration, which vary from z_{acc}=0.14 to
z_{acc}=0.59. Although these failings are largely cured by including
higher-order terms (3 or 4 parameters) this results in new degeneracies which
open up large regions of previously ruled-out parameter space. Finally we test
the parametrisations against a suite of theoretical quintessence models. The
widely used linear expansion in z is generally the worst, with errors of up to
10% at z=1 and 20% at z > 2. All of this casts serious doubt on the usefulness
of the standard two-parameter compressions in the coming era of high-precision
dark energy cosmology and emphasises the need for decorrelated compressions
with at least three parameters.


title: Cosmic Filaments in Superclusters

abstract:
  Large-scale structure calculations show that modest overdensity filaments
will connect clusters of galaxies and these filaments are reservoirs of
baryons, mainly in gaseous form. To determine whether such filaments exist, we
have examined the UV absorption line properties of three AGNs projected behind
possible filaments in superclusters of galaxies; the AGNs lie within 3 Mpc of
the centerlines of loci connecting clusters. All three lines of sight show
absorption in Ly\alpha, Ly\beta, or/and OVI at redshifts within about 1300 km/s
of the nearby galaxy clusters that would define the closest filaments. For one
AGN, the absorption line redshifts are close to the emission line redshift of
the AGN, so we cannot rule out self-absorption for this object. These
absorption line associations with superclusters are unlikely to have occurred
by chance, a result consistent with the presence of cosmic filaments within
superclusters.


title: A Low Solar Oxygen Abundance from the First Overtone OH Lines

abstract:
  An extremely high-resolution (> 10^5) high-S/N (> 10^3) solar spectrum has
been used to measure 15 very weak first overtone (Delta v = 2) infrared OH
lines, resulting in a low solar abundance of A(O) ~ 8.6 when MARCS, 3D, and
spatially and temporally averaged 3D model atmospheres are used. A higher
abundance is obtained with Kurucz (A(O) ~ 8.7) and Holweger & Muller (A(O) ~
8.8) model atmospheres. The low solar oxygen abundance obtained in this work is
in good agreement with a recent 3D analysis of [OI], OI, OH fundamental (Delta
v = 1) vibration-rotation and OH pure rotation lines (Asplund et al. 2004). The
present result brings further support for a low solar metallicity, and although
using a low solar abundance with OPAL opacities ruins the agreement between the
calculated and the helioseismic measurement of the depth of the solar
convection zone, recent results from the OP project show that the opacities
near the base of the solar convection zone are larger than previously thought,
bringing further confidence for a low solar oxygen abundance.


title:
Time-dependent Circulation Flows: Iron Enrichment in Cooling Flows with
  Heated Return Flows

abstract:
  We describe a new type of dynamical model for hot gas in galaxy groups and
clusters in which gas moves simultaneously in both radial directions.
Circulation flows are consistent with (1) the failure to observe cooling gas in
X-ray spectra, (2) multiphase gas observed near the centers of these flows and
(3) the accumulation of iron in the hot gas from Type Ia supernovae in the
central galaxy. Dense inflowing gas cools, producing a positive central
temperature gradient, as in normal cooling flows. Bubbles of hot, buoyant gas
flow outward. Circulation flows eventually cool catastrophically if the outward
flowing gas transports mass but no heat; to maintain the circulation both mass
and energy must be supplied to the inflowing gas over a large volume, extending
to the cooling radius. The rapid radial recirculation of gas produces a flat
central core in the gas iron abundance, similar to many observations. We
believe the circulation flows described here are the first gasdynamic,
long-term evolutionary models that are in good agreement with all essential
features observed in the hot gas: little or no gas cools as required by XMM
spectra, the gas temperature increases outward near the center, and the gaseous
iron abundance is about solar near the center and decreases outward.


title:
Strong Turbulence in the Cool Cores of Galaxy Clusters: Can Tsunamis
  Solve the Cooling Flow Problem?

abstract:
  Based on high-resolution two-dimensional hydrodynamic simulations, we show
that the bulk gas motions in a cluster of galaxies, which are naturally
expected during the process of hierarchical structure formation of the
universe, have a serous impact on the core. We found that the bulk gas motions
represented by acoustic-gravity waves create local but strong turbulence, which
reproduces the complicated X-ray structures recently observed in cluster cores.
Moreover, if the wave amplitude is large enough, they can suppress the
radiative cooling of the cores. Contrary to the previous studies, the heating
is operated by the turbulence, not weak shocks. The turbulence could be
detected in near-future space X-ray missions such as ASTRO-E2.


title:
Detailed spectral analysis of the 260 ksec XMM-Newton data of
  1E1207.4-5209 and significance of a 2.1 keV absorption feature

abstract:
  We have reanalyzed the 260 ksec XMM-Newton observation of 1E1207.4-5209.
There are several significant improvements over previous work. Firstly, a much
broader range of physically plausible spectral models was used. Secondly, we
have utilized a more rigorous statistical analysis. The standard F-distribution
was not employed, but rather the exact finite statistics F-distribution was
determined by Monte-Carlo simulations. This approach was motivated by the
recent work of Protassov et al. (2002) and Freeman et al. (1999). They
demonstrated that the standard F-distribution is not even asymptotically
correct when applied to assess the signficance of additional absorption
features in a spectrum. With our improved analysis we do not find a third and
fourth spectral feature (Bignami et al. (2003), De Luca et al. (2004)) in
1E1207.4-5209, but only the two broad absorption features previously reported
(Sanwal et al. (2002), Hailey and Mori (2002)). Two additional statistical
tests, one line model dependent and the other line model independent confirmed
our modified F-test analysis. For all physically plausible continuum models
where the weak residuals are strong enough to fit, the residuals occur at the
instrument Au-M edge. As a sanity check we confirmed that the residuals are
consistent in strength and position with the instrument Au-M residuals observed
in 3C273.


title: Age-Distance diagram for close-by young neutron stars

abstract:
  An age--distance diagram for close-by young isolated neutron stars of
different types is introduced and discussed. It is shown that such a diagram
can be a useful tool for studying of populations of sources if their
detectability strongly depends on age and distance.


title: High-Resolution Observations in B1-IRS: ammonia, CCS and water masers

abstract:
  We present a study of the structure and dynamics of the star forming region
B1-IRS (IRAS 03301+3057) using the properties of different molecules at high
angular resolution (~4''). We have used VLA observations of NH3, CCS, and H2O
masers at 1 cm. CCS emission shows three clumps around the central source, with
a velocity gradient from red to blueshifted velocities towards the protostar,
probably due to the interaction with outflowing material. Water maser emission
is elongated in the same direction as a reflection nebula detected at 2micron
by 2MASS, with the maser spots located in a structure of some hundreds of AU
from the central source, possibly tracing a jet. We propose a new outflow model
to explain all our observations, consisting of a molecular outflow near the
plane of the sky. Ammonia emission is extended and anticorrelated with CCS. We
have detected for the first time this anticorrelation at small scales (1400 AU)
in a star forming region.


title:
Cosmological parameter analysis including SDSS Ly-alpha forest and
  galaxy bias: constraints on the primordial spectrum of fluctuations, neutrino
  mass, and dark energy

abstract:
  We combine the constraints from the recent Ly-alpha forest and bias analysis
of the SDSS with previous constraints from SDSS galaxy clustering, the latest
supernovae, and WMAP . Combining WMAP and the lya we find for the primordial
slope n_s=0.98\pm 0.02. We see no evidence of running, dn/d\ln k=-0.003\pm
0.010, a factor of 3 improvement over previous constraints. We also find no
evidence of tensors, r<0.36 (95% c.l.). A positive correlation between tensors
and primordial slope disfavors chaotic inflation type models with steep slopes:
V \propto \phi^4 is outside the 3-sigma contour. For the amplitude we find
sigma_8=0.90\pm 0.03 from the lyaf and WMAP alone. We find no evidence of
neutrino mass: for the case of 3 massive neutrino families with an inflationary
prior, \sum m_{\nu}<0.42eV and the mass of lightest neutrino is m_1<0.13eV at
95% c.l. For the 3 massless + 1 massive neutrino case we find m_{\nu}<0.79eV
for the massive neutrino, excluding at 95% c.l. all neutrino mass solutions
compatible with the LSND results. We explore dark energy constraints in models
with a fairly general time dependence of dark energy equation of state, finding
Omega_lambda=0.72\pm 0.02, w(z=0.3)=-0.98^{+0.10}_{-0.12}, the latter changing
to w(z=0.3)=-0.92^{+0.09}_{-0.10} if tensors are allowed. We find no evidence
for variation of the equation of state with redshift,
w(z=1)=-1.03^{+0.21}_{-0.28}. These results rely on the current understanding
of the lyaf and other probes, which need to be explored further both
observationally and theoretically, but extensive tests reveal no evidence of
inconsistency among different data sets used here.


title: Dynamical Mass Estimates for Five Young Massive Stellar Clusters

abstract:
  We have obtained high-dispersion spectra for four massive star clusters in
the dwarf irregular galaxies NGC 4214 and NGC 4449, using the HIRES
spectrograph on the Keck I telescope. Combining the velocity dispersions of the
clusters with structural parameters and photometry from images taken with HST,
we estimate mass-to-light ratios and compare these with simple stellar
population (SSP) models in order to constrain the stellar mass functions (MFs).
For all clusters we find mass-to-light ratios which are similar to or slightly
higher than for a Kroupa MF, and thereby rule out any MF which is deficient in
low-mass stars compared to a Kroupa-type MF. The four clusters have virial
masses ranging between 2.1E5 Msun and 1.5E6 Msun, half-light radii between 3.0
and 5.2 pc, estimated core densities in the range 2E3 Msun pc^-3 to 2E5 Msun
pc^-3 and ages between 200 Myr and 800 Myr. We also present new high-dispersion
near-infrared spectroscopy for a luminous young (about 15 Myr) cluster in the
nearby spiral galaxy NGC 6946, which we have previously observed with HIRES.
The new measurements in the infrared agree well with previous estimates of the
velocity dispersion, yielding a mass of about 1.7E6 Msun. The properties of the
clusters studied here are all consistent with the clusters being young versions
of the old globular clusters found around all major galaxies.


title:
INTEGRAL, XMM-Newton and Rossi-XTE Observations of the State Transition
  of the X-ray Transient and Black Hole Candidate XTE J1720-318

abstract:
  We report the results of extensive high-energy observations of the X-ray
transient and black hole candidate XTE J1720-318 performed with INTEGRAL,
XMM-Newton and RXTE. The source, which underwent an outburst in January 2003,
was observed in February in a spectral state dominated by a soft component with
a weak high-energy tail. The XMM-Newton data provided a high column density Nh
of 1.2*e22 cm^{-2} which suggests that the source lies at the Galactic Center
distance. The simultaneous RXTE and INTEGRAL Target of Opportunity observations
allowed us to measure the weak and steep tail, typical of a black-hole binary
in the so-called High/Soft State. We could follow the evolution of the source
outburst over several months using the INTEGRAL Galactic Center survey
observations. The source regained activity at the end of March: it showed a
clear transition towards a much harder state, and then decayed to a quiescent
state in summer. In the hard state, the source was detected up to 200 keV with
a typical power law index of 1.8 and a peak luminosity of 7.5*e36 ergs s^{-1}
in the 2-100 keV band, for an assumed distance of 8 kpc. We conclude that XTE
J1720-318 is indeed representative of the class of the black hole X-ray novae
which populate our Galactic bulge and we discuss its properties in the frame of
the spectral models used for transient black hole binaries.


title:
Effects of differential and uniform rotation on nonlinear electromotive
  force in a turbulent flow

abstract:
  An effect of the differential rotation on the nonlinear electromotive force
in MHD turbulence is found. It includes a nonhelical $\alpha$ effect which is
caused by a differential rotation, and it is independent of a hydrodynamic
helicity. There is no quenching of this effect contrary to the quenching of the
usual $\alpha$ effect caused by a hydrodynamic helicity. The nonhelical
$\alpha$ effect vanishes when the rotation is constant on the cylinders which
are parallel to the rotation axis. The mean differential rotation creates also
the shear-current effect which changes its sign with the nonlinear growth of
the mean magnetic field. However, there is no quenching of this effect. These
phenomena determine the nonlinear evolution of the mean magnetic field. An
effect of a uniform rotation on the nonlinear electromotive force is also
studied. A nonlinear theory of the ${\bf \Omega} {\bf \times} \bar{\bf J}$
effect is developed, and the quenching of the hydrodynamic part of the usual
$\alpha$ effect which is caused by a uniform rotation and inhomogeneity of
turbulence, is found. Other contributions of a uniform rotation to the
nonlinear electromotive force are also determined. All these effects are
studied using the spectral $\tau$ approximation (the third-order closure
procedure). An axisymmetric mean-field dynamo in the spherical and cylindrical
geometries is considered. The nonlinear saturation mechanism based on the
magnetic helicity evolution is discussed. It is shown that this universal
mechanism is nearly independent of the form of the flux of magnetic helicity,
and it requires only a nonzero flux of magnetic helicity. Astrophysical
applications of these effects are discussed.


title:
High Resolution X-ray Spectra of the Brightest OB Stars in the Cygnus
  OB2 Association

abstract:
  The Cygnus OB2 Association contains some of the most luminous OB stars in our
Galaxy, the brightest of which are also among the most luminous in X-rays. We
have obtained a Chandra High Energy Transmission Grating Spectrometer (HETGS)
observation centered on Cyg OB2 No. 8a, the most luminous X-ray source in the
Association. Although our analysis will focus on the X-ray properties of Cyg
OB2 No. 8a, we also present limited analyses of three other OB stars (Cyg OB2
Nos. 5, 9, and 12). Applying standard diagnostic techniques as used in previous
studies of early-type stars, we find that the X-ray properties of Cyg OB2 No.
8a are very similar to those of other OB stars that have been observed using
high-resolution X-ray spectroscopy. From analyses of the He-like ion "fir"
emission lines, we derive radial distances of the He-like line emission sources
and find these fir-inferred radii are consistent with their corresponding X-ray
continuum optical depth unity radii. Contrary to other O-star results, the
emission lines of Cyg OB2 No. 8a show a large range in line centroid shifts
(roughly -800 to +250 km/s). We discuss the implications of our results in
light of the fact that Cyg OB2 No. 8a is a member of a rather tight stellar
cluster, and shocks could arise at interfaces with the winds of these other
stars.


title:
The Linear Theory Power Spectrum from the Lyman-alpha Forest in the
  Sloan Digital Sky Survey

abstract:
  We analyze the SDSS Ly-alpha forest P_F(k,z) measurement to determine the
linear theory power spectrum. Our analysis is based on fully hydrodynamic
simulations, extended using hydro-PM simulations. We account for the effect of
absorbers with damping wings, which leads to an increase in the slope of the
linear power spectrum. We break the degeneracy between the mean level of
absorption and the linear power spectrum without significant use of external
constraints. We infer linear theory power spectrum amplitude
Delta^2_L(k_p=0.009s/km,z_p=3.0)=0.452_{-0.057-0.116}^{+0.069+0.141} and slope
n_eff=-2.321_{-0.047-0.102}^{+0.055+0.131} (possible systematic errors are
included through nuisance parameters in the fit - a factor >~5 smaller errors
would be obtained on both parameters if we ignored modeling uncertainties). The
errors are correlated and not perfectly Gaussian, so we provide a chi^2 table
to accurately describe the results. The result corresponds to sigma_8=0.85,
n=0.94, for a LCDM model with Omega_m=0.3, Omega_b=0.04, and h=0.7, but is most
useful in a combined fit with the CMB. The inferred curvature of the linear
power spectrum and the evolution of its amplitude and slope with redshift are
consistent with expectations for LCDM models, with the evolution of the slope,
in particular, being tightly constrained. We use this information to constrain
systematic contamination, e.g., fluctuations in the UV background. This paper
should serve as a starting point for more work to refine the analysis,
including technical improvements such as increasing the size and number of the
hydrodynamic simulations, and improvements in the treatment of the various
forms of feedback from galaxies and quasars.


title:
Physical effects on the Lyman-alpha forest flux power spectrum: damping
  wings, ionizing radiation fluctuations, and galactic winds

abstract:
  We explore several physical effects on the power spectrum of the Lyman-alpha
forest transmitted flux. The effects we investigate here are usually not part
of hydrodynamic simulations and so need to be estimated separately. The most
important effect is that of high column density absorbers with damping wings,
which add power on large scales. We compute their effect using the
observational constraints on their abundance as a function of column density.
Ignoring their effect leads to an underestimation of the slope of the linear
theory power spectrum. The second effect we investigate is that of fluctuations
in the ionizing radiation field. For this purpose we use a very large high
resolution N-body simulation, which allows us to simulate both the fluctuations
in the ionizing radiation and the small scale LyaF within the same simulation.
We find an enhancement of power on large scales for quasars and a suppression
for galaxies. The strength of the effect rapidly increases with increasing
redshift, allowing it to be uniquely identified in cases where it is
significant. We develop templates which can be used to search for this effect
as a function of quasar lifetime, quasar luminosity function, and attenuation
length. Finally, we explore the effects of galactic winds using hydrodynamic
simulations. We find the wind effects on the LyaF power spectrum to be be
degenerate with parameters related to the temperature of the gas that are
already marginalized over in cosmological fits. While more work is needed to
conclusively exclude all possible systematic errors, our results suggest that,
in the context of data analysis procedures where parameters of the LyaF model
are properly marginalized over, the flux power spectrum is a reliable tracer of
cosmological information.


title: The complex structure of low luminosity AGN : NGC 4579

abstract:
  We have modelled the low luminosity AGN NGC 4579 by explaining both the
continuum and the line spectra. It was found that the nuclear emission is
dominated by an AGN. However, a young starburst, an older starburst with age of
4.5 Myr, and shock dominated clouds with velocities of 100, 300, and 500 km/s
also contribute. HII regions appear in the the extended regions (about 1 kpc),
where radiation and shock dominated clouds with Vs=100 km/s prevail. The
continuum SED of NGC 4579 is characterized by the strong flux from an old
stellar population. Emissions in the radio range show synchrotron radiation
from the base of the jet outflowing from the accretion disc within 0.1 pc from
the active centre. Radio emission within intermediate distances (10-20 pc) is
explained by the bremsstrahlung from gas downstream of low velocity shocks
(Vs=100 km/s) reached by a relatively low radiation flux from the AC. In
extended regions (>100 pc) the radio emission is synchrotron radiation created
by the Fermi mechanism at the shock front. The shocks are created by collision
of clouds with the jet. ~


title:
Associated HI absorption in the z=3.4 radio galaxy B2 0902+343 observed
  with the GMRT

abstract:
  We have made observations of the associated HI absorption of a high redshift
radio galaxy 0902+34 at z=3.395 with the Giant Meterwave Radio Telescope in the
$323\pm1$ MHz band. We find a narrow absorption line with a flux density of
11.5 mJy at a redshift of 3.397 consistent with that observed by Uson et al.
(1991), Briggs et al. (1993) and de Bruyn (1996).A weak broad absorption
feature reported by de Bruyn (1996) has not been detected in our observations.
We also place an upper limit of 4 mJy (2 $\sigma$) on emission line strength at
the position where Uson et al. (1991) claimed to have found a narrow emission
line.


title:
Convection in galaxy-cluster plasmas driven by active galactic nuclei
  and cosmic-ray buoyancy

abstract:
  Turbulent heating may play an important role in galaxy-cluster plasmas, but
if turbulent heating is to balance radiative cooling in a quasi-steady state,
some mechanism must set the turbulent velocity to the required value. This
paper explores one possible regulating mechanism associated with an active
galactic nucleus at cluster center. A steady-state model for the intracluster
medium is presented in which radiative cooling is balanced by a combination of
turbulent heating and thermal conduction. The turbulence is generated by
convection driven by the buoyancy of cosmic rays produced by a central radio
source. The cosmic-ray luminosity is powered by the accretion of intracluster
plasma onto a central black hole. The model makes the rather extreme assumption
that the cosmic rays and thermal plasma are completely mixed. Although the
intracluster medium is convectively unstable near cluster center in the model
solutions, the specific entropy of the thermal plasma still increases outwards
because of the cosmic-ray modification to the stability criterion. The model
provides a self-consistent calculation of the turbulent velocity as a function
of position, but fails to reproduce the steep central density profiles observed
in clusters. The principal difficulty is that in order for the fully mixed
intracluster medium to become convectively unstable, the cosmic-ray pressure
must become comparable to or greater than the thermal pressure within the
convective region. The large cosmic-ray pressure gradient then provides much of
the support against gravity, reducing the thermal pressure gradient near
cluster center and decreasing the central plasma density gradient. A more
realistic AGN-feedback model of intracluster turbulence in which relativistic
and thermal plasmas are only partially mixed may have greater success.


title: Summary Talk of the X Latin American Workshop on Plasma Physics

abstract:
  Of the many important topics that were discussed at the workshop, I summarize
and comment on 25 presentations, which I found to be particularly interesting.
They fall into all of the areas covered in the conference: basic plasma
phenomena, space and astrophysical plasmas, technological applications of
plasma, and thermonuclear fusion.


title:
The Relationship Between Black Hole Mass and Velocity Dispersion in
  Seyfert 1 Galaxies

abstract:
  Black hole masses in active galactic nuclei (AGN) are difficult to measure
using conventional dynamical methods, but can be determined using the technique
of reverberation mapping. However, it is important to verify that the results
of these different methods are equivalent. This can be done indirectly, using
scaling relations between the black hole and the host galaxy spheroid. For this
purpose, we have obtained new measurements of the bulge stellar velocity
dispersion, sigma, in Seyfert 1 galaxies. These are used in conjunction with
the M_bh -- sigma relation to validate nuclear black hole masses, M_bh, in
active galaxies determined through reverberation mapping. We find that Seyfert
galaxies follow the same M_bh -- sigma relation as non-active galaxies,
indicating that reverberation mapping measurements of M_bh are consistent with
those obtained using other methods. We also reconsider the relationship between
bulge absolute magnitude, M_bulge, and black hole mass. We find that Seyfert
galaxies are offset from non-active galaxies, but that the deviation can be
entirely understood as a difference in bulge luminosity, not black hole mass;
Seyfert hosts are brighter than normal galaxies for a given value of their
velocity dispersion, perhaps as a result of younger stellar populations.


title:
High-spatial-resolution CN and CS observation of two regions of massive
  star formation

abstract:
  Molecular line CN, CS and mm continuum observations of two intermediate- to
high-mass star-forming regions - IRAS20293+3952 and IRAS19410+2336 - obtained
with the Plateau de Bure Interferometer at high spatial resolution reveal
interesting characteristics of the gas and dust emission. In spite of the
expectation that the CN and CS morphology might closely follow the dense gas
traced by the dust continuum, both molecules avoid the most central cores.
Comparing the relative line strengths of various CN hyperfine components, this
appears not to be an opacity effect but to be due to chemical and physical
effects. The CN data also indicate enhanced emission toward the different
molecular outflows in the region. Regarding CS, avoiding the central cores can
be due to high optical depth, but the data also show that the CS emission is
nearly always associated with the outflows of the region. Therefore, neither CS
nor CN appear well suited for dense gas and disk studies in these two sources,
and we recommend the use of different molecules for future massive disk
studies. An analysis of the 1 and 3mm continuum fluxes toward IRAS20293+3952
reveals that the dust opacity index beta is lower than the canonical value of
2. Tentatively, we identify a decreasing gradient of beta from the edge of the
core to the core center. This could be due to increasing optical depth toward
the core center and/or grain growth within the densest cores and potential
central disks. We detect 3mm continuum emission toward the collimated outflow
emanating from IRAS20293+3952. The spectral index of alpha ~ 0.8 in this region
is consistent with standard models for collimated ionized winds.


title: The eddy heat-flux in rotating turbulent convection

abstract:
  The three components of the heat-flux vector $F =\rho C_p <u^\prime T^\prime>
are numerically computed for a stratified rotating turbulent convection using
the NIRVANA code in a flat box. The latitudinal component $F_\theta$ proves to
be negative (positive) in the northern (southern) hemisphere so that the heat
always flows towards the poles. As a surprise, the radial heat-flux $F_r$ peaks
at the equator rather than at the poles (Taylor numbers O(10^6)). The same
behavior is observed for the radial turbulence intensity $<u_r^{\prime 2}>$
which for \emph{free} turbulence is also believed to peak at the poles (see Eq.
(19) below). As we can show, however, the consequences of this unexpected
result (also obtained by Kaepylae, Korpi and Tuominen 2004) for the theory of
differential rotation are small as mainly the $F_\theta$ is responsible to
solve the `Taylor number puzzle'. In all our simulations the azimuthal
component $F_\phi$ proves to be negative so that the rotating turbulence
produces an westwards directed azimuthal heat-flux which should be observable.
Fluctuations with higher temperature are expected to be anticorrelated with
their own angular velocity fluctuations. We find this rotation-induced result
as understandable as the $F_\phi$ is closely related to the radial
\Lambda-effect which is known to be also negative in stratified and rapidly
rotating convection zones.


title:
The influence of the Hall effect on the global stability of cool
  protostellar disks

abstract:
  The influence of the Hall effect on the global stability of cool Kepler disks
under the influence of an axial magnetic field is considered. For sufficiently
large magnetic Reynolds numbers Rm the magnetorotational instability (MRI)
exists in a finite interval of magnetic field amplitudes, $B$_{min} < $B$ <
$B$_{max}. For Kepler disks the pure MRI needs both rather high Rm
(representing the needed electrical conductivity) as well as $B$_{min} of order
0.1 G. The magnetic field pattern resulting from our global and linear
calculations is of quadrupolar parity. For magnetic fields $antiparallel$ to
the rotation axis the Hall effect reduces the minimum magnetic Reynolds number
by about one order of magnitude. The $B$_{min}, however, is even (sightly)
increased (see Fig. 6). For magnetic fields $parallel$ to the rotation axis the
Hall effect drives its own instability without the action of the Lorentz force.
The corresponding critical magnetic Reynolds number proves to be larger with
Hall effect (Rm ~ 10) than without Hall effect (Rm ~ 7) so that the Hall effect
for parallel fields even disturbs the formation of MHD-instability in cool
protoplanetary disks. If the disk is supercritical then the main result of the
Hall effect for positive fields is the strong reduction of the minimum magnetic
field amplitude which is necessary to start the instability. Observations must
show whether in star-forming regions the rotation axis and the magnetic field
orientation are correlated or are anticorrelated. If the magnetic fields are
high enough then our model predicts the dominance of fields antiparallel to the
rotation axis.


title:
The Needles in the Haystack survey: searching for X-ray selected normal
  galaxies

abstract:
  In this paper we present the first results from an on-going serendipitous
survey aiming to identify X-ray selected `normal' galaxies (i.e. not AGN
dominated) by combining archival XMM-Newton data with the Sloan Digital Sky
Survey. In the first 4.5deg2 of this program we have identified a total of 11
`normal' galaxy candidates (8 of them with optical spectroscopy) with fluxes
f_X(0.5-8keV)~1e-15-1e-13cgs. These sources are selected to have low
X-ray--to--optical flux ratio (logf_X/f_{opt}<-2), soft X-ray spectral
properties and optical spectra, when available, consistent with the presence of
a stellar ionising continuum. These sources comprise both early and late type
systems at redshifts z<0.2 with luminosities L_X(0.5-8keV)~1e39-1e42cgs. This
dataset provides the first tight constraint on the surface density of X-ray
selected `normal' galaxies at relatively bright fluxes spanning two orders of
magnitude (1e-15 - 1e-13cgs). The slope of the `normal' galaxy logN-logS in the
above flux range is estimated -1.4\pm0.3 consistent with the euclidean
prediction. We also discuss the prospects of `normal' galaxy studies at X-ray
wavelengths using both our continuously expanding survey and future X-ray
missions.


title: NG7538 IRS1 N: modeling a circumstellar maser disk

abstract:
  We present an edge-on Keplerian disk model to explain the main component of
the 12.2 and 6.7 GHz methanol maser emission detected toward NGC7538-IRS1 N.
The brightness distribution and spectrum of the line of bright masers are
successfully modeled with high amplification of background radio continuum
emission along velocity coherent paths through a maser disk. The bend seen in
the position-velocity diagram is a characteristic signature of differentially
rotating disks. For a central mass of 30 solar masses, suggested by other
observations, our model fixes the masing disk to have inner and outer radii of
about 270 AU and 750 AU.


title: Thick disks and halos of spiral galaxies M 81, NGC 55 and NGC 300

abstract:
  By using images from the HST/WFPC2/ACS archive, we have analyzed the spatial
distribution of the AGB and RGB stars along the galactocentric radius of nearby
spiral galaxies M~81, NGC 300 and NGC 55. Using color-magnitude diagrams and
stellar luminosity functions, we gauge the stellar contents of the surroundings
of three galaxies. The red giant population (RGB) identified at large
galactocentric radii yields a distance of $3.85\pm0.08$ Mpc for M~81,
$2.12\pm0.10$ Mpc for NGC 55, and $2.00\pm0.13$ Mpc for NGC 300, and a mean
stellar metallicity of $-$0.65, $-$1.25, and $-$0.87. We find that there are
two number density gradients of RGB stars along the radius, which correspond to
the thick disk and halo components of the galaxies. We confirm the presence of
metallicity gradient of evolved stars at these galaxies, based on the
systematic changes of the color distribution of red giant stars. These results
imply that thick disk might be a general feature of the spiral galaxies, and
endorse a further investigation of the outer stellar edges of nearby spirals,
which is critical in constraining the origin and evolution of galaxies.


title: Molecules in bipolar proto-planetary nebulae

abstract:
  Two bipolar proto-planetary nebulae, IRAS16594-4656 and IRAS17150-3224, have
been detected in various molecular lines, namely CO, ^{13}CO, HCN and CN, and
remain undetected in several other species. CO(J=2-1) and CO(J=3-2) line
profiles are compared to new spectra of similar PPN candidates, previously
undetected in CO(J=2-1): CPD-53^{o}5736, IRAS17106-3046, IRAS17245-3951 and
IRAS17441-2411. CO(J=2-1) maps of IRAS16594-4656 and IRAS17150-3224 show that
both PPNe have little separation between blue, centre and red-shifted emission,
and also that the CO(J=2-1) emission is of a similar size to the telescope
beam. Fractional abundances of all detected molecules (except CO) are
calculated using the results of CO line modelling and a simple
photodissociation model. For those species not detected, upper limits are
derived. Comparisons between these fractional abundances and those of other
PPNe show that IRAS16594-4656 and IRAS17150-3224 are quite under-abundant when
compared to molecule-rich sources like CRL618, CRL2688 and OH231.8+4.2. As a
reason for this deficit, the difference in circumstellar envelope/torus density
between the molecule-rich sources and the molecule-poor sources is proposed,
and supported by a chemical model which follows the transition of a
circumstellar envelope through the AGB phase and into the PPN phase of
evolution. The model includes the effects of UV radiation, cosmic rays and also
X-rays. Finally, the post-AGB ages of these two objects (200-400 yr) are
estimated using CN/HCN and HCN/CO ratios and both ages are found to be in
agreement with previous figures cited in the literature, IRAS17150-3224 being
the younger of the two PPNe.


title:
Why the Canis Major overdensity is not due to the Warp: analysis of its
  radial profile and velocities

abstract:
  In response to criticism by Momany et al. (2004), that the
recently-identified Canis Major (CMa) overdensity could be simply explained by
the Galactic warp, we present proof of the existence of a stellar population in
the direction of CMa that cannot be explained by known Galactic components. By
analyzing the radial distribution of counts of M-giant stars in this direction,
we show that the Momany et al. (2004) warp model overestimates the number of
stars in the Northern hemisphere, hence hiding the CMa feature in the South.
The use of a better model of the warp has little influence on the morphology of
the overdensity and clearly displays an excess of stars grouped at a distance
of D=7.2\pm 0.3 kpc. To lend further support to the existence of a population
that does not belong to the Galactic disc, we present radial velocities of
M-giant stars in the centre of the CMa structure that were obtained with the
2dF spectrograph at the AAT. The extra population shows a radial velocity of
vr=109\pm4 km/s, which is significantly higher than the typical velocity of the
disc at the distance of CMa. This population also has a low dispersion (13\pm4
km/s). The Canis Major overdensity is therefore highly unlikely to be due to
the Galactic warp, adding weight to the hypothesis that we are observing a
disrupting dwarf galaxy or its remnants. This leads to questions on what part
of CMa was previously identified as the Warp and how to possibly disentangle
the two structures.


title: A note on Temperature Profiles of rich Clusters of Galaxies

abstract:
  We derive here the mean temperature profile for a sample of hot, medium
distant clusters recently observed with XMM-Newton, whose profiles are
available from the literature, and compare it with the mean temperature profile
found from BeppoSAX data. The XMM-Newton and BeppoSAX profiles are in good
agreement between 0.05 and 0.25 r_180. From 0.25 to about 0.5 r_180 both
profiles decline, however the BeppoSAX profile does so much more rapidly than
the XMM-Newton profile.


title: Turbulence in circumstellar disks

abstract:
  We investigate the analogy between circumstellar disks and the Taylor-Couette
flow. Using the Reynolds similarity principle, the analogy results in a number
of parameter-free predictions about stability of the disks, and their turbulent
transport properties, provided the disk structure is available. We discuss how
the latter can be deduced from interferometric observations of circumstellar
material. We use the resulting disk structure to compute the molecular
transport coefficients, including the effect of ionization by the central
object. The resulting control parameter indicates that the disk is well into
the turbulent regime. The analogy is also used to compute the effective
accretion rate, as a function of the disk characteristic parameters (orbiting
velocity, temperature and density). These values are in very good agreement
with experimental, parameter-free predictions derived from the analogy. The
turbulent viscosity is also computed and found to correspond to an
$\alpha$-parameter $2\times 10^{-4}<\alpha<2\times 10^{-2}$. Predictions
regarding fluctuations are also checked: luminosity fluctuations in disks do
obey the same universal distribution as energy fluctuations observed in a
laboratory turbulent flow. Radial velocity dispersion in the outer part of the
disk is predicted to be of the order of 0.1 km/s, in agreement with available
observations. All these issues provide a proof of the turbulent character of
the circumstellar disks, as well as a parameter-free theoretical estimate of
effective accretion rates.


title: Infrared Observations of AGN

abstract:
  We present results from an imaging and spectroscopic study of the dust
properties of Seyfert galaxies in the 1-10um range. The data are compared to
state of the art models of torus emission to constrain geometrical and physical
properties of the obscuring medium.


title:
Auto and cross correlation of phases of the whole-sky CMB and foreground
  maps from the 1-year WMAP data

abstract:
  The issue of non-Gaussianity is not only related to distinguishing the
theories of the origin of primordial fluctuations, but also crucial for the
determination of cosmological parameters in the framework of inflation
paradigm. We present an advenced method for testing non-Gaussianity on the
whole-sky CMB anisotropies. This method is based on the Kuiper's statistic to
probe the two-dimensional uniformity on a periodic mapping square associating
phases: return mapping of phases of the derived CMB (similar to auto
correlation) and cross correlations between phases of the derived CMB and
foregrounds. Since phases reflect morphology, detection of cross correlation of
phases signifies the contamination of foreground signals in the derived CMB
map. The advantage of this method is that one can cross check the auto and
cross correlation of phases of the derived CMB and foregrounds, and mark off
those multipoles in which the non-Gaussianity results from the foreground
contaminations. We apply this statistic on the derived signals from the 1-year
WMAP data. The auto-correlations of phases from the ILC map shows the
significance above 95% CL against the random phase hypothesis on 17 spherical
harmonic multipoles, among which some have pronounced cross correlations with
the foreground maps. We conclude that most of the non-Gaussianity found in the
derived CMB maps are from foreground contaminations, except, among others, l=6.
With this method we are better equipped to approach the issue of
non-Gaussianity of primordial origin for the upcoming PLANCK mission.


title: Multiwavelength Survey by Yale-Chile

abstract:
  We describe MUSYC, a 1 square degree multiwavelength survey that will make
unique contributions in several areas and is particularly well suited for the
study of high redshift AGN.


title:
Abundance gradient in Local Group galaxies using Asymptotic Giant Branch
  stars

abstract:
  Simultaneous IJKs observations allow us to statistically select AGB stars,
both M and C type, from RGB and younger or foreground stars in nearby galaxies.
Regions of different metallicity identified from the distribution of the C/M
ratio show a considerable variation across the surface of the Magellanic Clouds
and NGC 6822.


title: Conceptual Steps towards Exploring the Fundamental Nature of our Sun

abstract:
  One of the basic questions of solar research is the nature of the Sun. We
show here how the plasma nature of the Sun leads to the self-generation of
solar activity. The release of magnetic, rotational, gravitational, nuclear
energies and that of the gravity mode oscillations deviate from uniformity and
spherical symmetry. Through instabilities they lead to the emergence of
sporadic and localized regions like flux tubes, electric filaments, magnetic
elements and high temperature regions. A systematic approach exploring the
solar collective degrees of freedom, extending to ordering phenomena of the
magnetic features related to Higgs fields, is presented. Handling solar
activity as transformations of energies from one form to another one presents a
picture on the network of the energy levels of the Sun, showing that the Sun is
neither a mere "ball of gas" nor a "quiescent steady-state fusion-reactor
machine", but a complex self-organizing system. Since complex self-organizing
systems are similar to living systems (and, by some opinion, identical with
them), we also consider what arguments indicate the living nature of the Sun.
Thermodynamic characteristics of the inequilibrium Sun are found important in
this respect and numerical estimations of free energy rate densities and
specific exergies are derived.
  KEY WORDS solar physics, degrees of freedom, self-organizing complex systems,
non-equilibrium thermodynamics, astrobiology
  CLASSIFICATION PACS: 01.70.+w, 96.60.Rd


title: The Black Hole- Bulge Relations in Active Galactic Nuclei

abstract:
  We show that Massive Black Holes of AGNs follow the same approximately linear
relation with the luminosity of the host spheroid (bulge) found in normal
(quiescent) galaxies, with the black hole mass being ~0.002 that of the bulge.
We also demonstrate that Narrow line AGNs seem to have a significantly lower
Mbh/Lbulge ratio, which implies a new strong correlation between Mbh/Lbulge and
the width of the broad emission lines of AGNs. Combining existing data, new
observations and extrapolation schemes based on the Faber-Jackson relation, the
relation between the BH mass and the stellar velocity dispersion in the host
bulge of AGNs is constructed. It too agrees with the relation found in
quiescent galaxies.


title: Simulations of the Population of Centaurs I: The Bulk Statistics

abstract:
  Large-scale simulations of the Centaur population are carried out. The
evolution of 23328 particles based on the orbits of 32 well-known Centaurs is
followed for up to 3 Myr in the forward and backward direction under the
influence of the 4 massive planets. The objects exhibit a rich variety of
dynamical behaviour with half-lives ranging from 540 kyr (1996 AR20) to 32 Myr
(2000 FZ53). The mean half-life of the entire sample of Centaurs is 2.7 Myr.
The data are analyzed using a classification scheme based on the controlling
planets at perihelion and aphelion, previously given in Horner et al (2003).
Transfer probabilities are computed and show the main dynamical pathways of the
Centaur population. The total number of Centaurs with diameters larger than 1
km is estimated as roughly 44300, assuming an inward flux of one new
short-period comet every 200 yrs. The flux into the Centaur region from the
Edgeworth-Kuiper belt is estimated to be 1 new object every 125 yrs. Finally,
the flux from the Centaur region to Earth-crossing orbits is 1 new
Earth-crosser every 880 yrs


title:
Spectral properties of nonthermal X-ray emission from the shell-type SNR
  RX J1713.7-3946 as revealed by XMM-Newton

abstract:
  We present the results of our morphological and spectral study of properties
of the supernova remnant RX J1713.7-3946 based on data obtained with
XMM-Newton. Highly inhomogeneous structures, such as the bright spots,
filaments and dark voids, noted by Uchiyama et al. (2003), appear in the entire
bright western portion of the shell. In addition two narrow rims are found
which run parallel to each other from north to south in the western part of the
remnant. No complex structures are seen in the interior region of the remnant.
The X-ray spectra everywhere can be well represented with a power-law function
of photon index ranging within Gamma = 2.0-2.8. A clear difference of spectra
between the central dim region and the bright western portion is seen at lower
energies. This differences can be ascribed either to an additional thermal
component with electron temperature, kTe= 0.56keV from the center or,
alternatively, to an increase in column density of Delta NH ~ 0.3 x 10^22 cm^-2
in the western region. In the context of the recent discovery by the NANTEN
telescope of a molecular cloud apparently interacting with the western part of
the supernova remnant, the second possibility seems to be the more likely
scenario.


title: Phase-resolved spectroscopy of Geminga shows rotating hot spot(s)

abstract:
  Isolated neutron stars are seen in x-rays through their nonthermal and/or
surface thermal emissions. XMM-Newton observations of the Geminga pulsar show a
43 electron volt spectrum from the whole neutron star surface, as well as a
power-law component above 2 kiloelectron volts. In addition, we have detected a
hot (170 electron volts) thermal emission from an 60-meter-radius spot on the
pulsar s surface. Such a thermal emission, only visible at selected phase
intervals, may be coming from polar hot spot(s), long thought to exist as a
result of heating from magnetospheric accelerated particles. It may provide the
missing link between the x-ray and gamma-ray emission of the pulsar.


title: On the saturation of corotation resonances: a numerical study

abstract:
  [Abridged] The torque exerted by an external potential on a two-dimensional
gaseous disk at non-co-orbital corotation resonances is studied by means of
numerical simulations. The degree of saturation of these resonances is
important in determining whether an eccentric giant planet embedded in a
protoplanetary disk experiences an eccentricity excitation or damping. We
perform calculations restricted to one or two resonances to investigate the
properties of two neighboring corotation resonances, as well as the properties
of a corotation resonance that overlaps a Lindblad resonance. We find that
these properties hardly differ from the case of an isolated corotation
resonance. In particular, although the torque of two neighboring corotation
resonances may differ from the sum of the torques of the corresponding
resonances considered as isolated, it never exceeds the sum of the fully
unsaturated isolated corotation resonances, and it saturates in a fashion
similar to an isolated resonance. Similarly, the presence of an underlying
Lindblad resonance hardly affects the corotation torque, even if that resonance
implies a torque strong enough to significantly redistribute the azimuthally
averaged surface density profile, in which case the corotation torque scales
with the resulting vortensity gradient. This set of numerical experiments thus
essentially validates previous analytic studies. As a side result, we show that
corotation libration islands misrepresented by a mesh of too low resolution can
lead to a strongly overestimated corotation torque. This may be an explanation
why the eccentricity of embedded Jupiter-sized planets was never observed to
undergo an excitation in the numerical simulations performed so far.


title: The Origin of Fe II Emission in AGN

abstract:
  We used a very large set of models of broad emission line (BEL) clouds in AGN
to investigate the formation of the observed Fe II emission lines. We show that
photoionized BEL clouds cannot produce both the observed shape and observed
equivalent width of the 2200-2800A Fe II UV bump unless there is considerable
velocity structure corresponding to a microturbulent velocity parameter v_turb
> 100 km/s for the LOC models used here. This could be either microturbulence
in gas that is confined by some phenomenon such as MHD waves, or a velocity
shear such as in the various models of winds flowing off the surfaces of
accretion disks. The alternative way that we can find to simultaneously match
both the observed shape and equivalent width of the Fe II UV bump is for the Fe
II emission to be the result of collisional excitation in a warm, dense gas.
Such gas would emit very few lines other than Fe II. However, since the
collisionally excited gas would constitute yet another component in an already
complicated picture of the BELR, we prefer the model involving turbulence. In
either model, the strength of Fe II emission relative to the emission lines of
other ions such as Mg II depends as much on other parameters (either v_turb or
the surface area of the collisionally excited gas) as it does on the iron
abundance. Therefore, the measurement of the iron abundance from the FeII
emission in quasars becomes a more difficult problem.


title: Correlated X-ray and Optical Variability in V404 Cyg in Quiescence

abstract:
  We report simultaneous X-ray and optical observations of V404 Cyg in
quiescence. The X-ray flux varied dramatically by a factor of >20 during a 60ks
observation. X-ray variations were well correlated with those in Halpha,
although the latter include an approximately constant component as well.
Correlations can also be seen with the optical continuum, although these are
less clear. We see no large lag between X-ray and optical line variations; this
implies they are causally connected on short timescales. As in previous
observations, Halpha flares exhibit a double-peaked profile suggesting emission
distributed across the accretion disk. The peak separation is consistent with
material extending outwards to at least the circularization radius. The prompt
response in the entire Halpha line confirms that the variability is powered by
X-ray (and/or EUV) irradiation.


title: High Spatial Resolution HST/NICMOS Observations of Markarian 231

abstract:
  Observations of Markarian 231 at 1.1 microns taken with NICMOS on the Hubble
Space Telescope are described. The brightness of the object in the near
infrared and the inherent short-term stability of the NICMOS optical and
instrumental system enables application of special observational and analysis
techniques that effectively increase high spatial resolution. By these means,
we set an upper limit on the size of the core of the AGN nucleus at 8 mas
corresponding to a radial projected distance from the center of MArkarian 231
of ~ 3pc.


title:
Fate of Supermassive Black Holes and Evolution of the M(BH)-sigma
  Relation in Merging Galaxies: The Effect of Gaseous Dissipation

abstract:
  We analyze the effect of dissipation on the orbital evolution of supermassive
black holes (SMBHs) using high-resolution self-consistent gasdynamical
simulations of binary equal- and unequal-mass mergers of disk galaxies. The
galaxy models are consistent with the LCDM paradigm of structure formation and
the simulations include the effects of radiative cooling and star formation. We
find that equal-mass mergers always lead to the formation of a close SMBH pair
at the center of the remnant with separations limited solely by the adopted
force resolution of ~ 100 pc. Instead, the final SMBH separation in
unequal-mass mergers depends sensitively on how the central structure of the
merging galaxies is modified by dissipation. In the absence of dissipation, the
satellite galaxy can be entirely disrupted before the merger is completed
leaving its SMBH wandering at a distance too far from the center of the remnant
for the formation of a close pair. In contrast, we show that gas cooling
facilitates the pairing process by increasing the resilience of the companion
galaxy to tidal disruption. Moreover, we demonstrate that merging disk galaxies
constructed to obey the M(BH)-sigma relation, move relative to it depending on
whether they undergo a dissipational or collisionless merger, regardless of the
mass ratio of the merging systems. Collisionless simulations reveal that
remnants tend to move away from the mean relation highlighting the role of
gas-poor mergers as a possible source of scatter.
  In dissipational mergers, the interplay between strong gas inflows associated
with the formation of massive nuclear disks and the consumption of gas by star
formation provides the necessary fuel to the SMBHs and allows the merger
remnants to satisfy the relation.


title:
Luminosity functions of Lyman-alpha emitters at z=6.5, and z=5.7:
  evidence against reionization at z=6

abstract:
  Lyman-alpha emission from galaxies should be suppressed completely or
partially at redshifts beyond reionization. Without knowing the instrinsic
properties of galaxies at z = 6.5, this attenuation is hard to infer in any one
source, but can be infered from a comparison of luminosity functions of
lyman-alpha emitters at redshifts just before and after reionization. We
combine published surveys of widely varying depths and areas to construct
luminosity functions at z=6.5 and 5.7, where the characteristic luminosity
L_star and density phi_star are well constrained while the faint-end slope of
the luminosity function is essentially unconstrained. Excellent consistency is
seen in all but one published result. We then calculate the likelihood of
obtaining the z=6.5 observations given the z=5.7 luminosity function with (A)
no evolution and (B) an attenuation of a factor of three. Hypothesis (A) gives
an acceptable likelihood while (B) does not. This indicates that the z=6.5
lyman-alpha lines are not strongly suppressed by a neutral intergalactic medium
and that reionization was largely complete at z = 6.5.


title: A Galaxy at z = 6.545 and Constraints on the Epoch of Reionization

abstract:
  We report the discovery of a Lyman-alpha-emitting galaxy at redshift z=6.545
serendipitously identified in the course of spectroscopic follow-up of hard
X-ray sources on behalf of the Serendipitous Extragalactic X-Ray Source
Identification (SEXSI) survey. The line flux of the galaxy, 2.1e-17 erg/cm2/s,
is similar to line fluxes probed by narrow-band imaging surveys; the 5.2
square-arcminutes surveyed implies a surface density of z~6.5 Lyman-alpha
emitters somewhat higher than that inferred from narrow-band surveys. This
source marks the sixth Lyman-alpha-emitting galaxy identified at z~6.5, a
redshift putatively beyond the epoch of reionization when the damping wings of
the neutral hydrogen of the intergalactic medium is capable of severely
attenuating Lyman-alpha emission. By comparing the Lyman-alpha emitter
luminosity functions at z~5.7 and z~6.5, we infer that the intergalactic medium
may remain largely reionized from the local universe out to z~6.5.


title: Water Masers in W49 North and Sagittarius B2

abstract:
  Using the Very Large Array (VLA) of the National Radio Astronomy Observatory
in the A and B configurations, we have obtained simultaneous high resolution
observations of both the 22 GHz water maser lines as well as the 22 GHz
continuum for the H II regions W49N and Sagittarius B2. The angular resolution
of both observations is ~0.1", which at the distance of W49N (11.4 kpc; Gwinn,
Moran, & Reid 1992) and Sgr B2 (8.5 kpc) corresponds to a physical size of
<1000 AU in both sources. The velocity coverage for W49N is +/- 435 km/s;
positions for 316 water maser components were obtained. The velocity coverage
for Sgr B2 is -40 to +120 km/s; positions for 68 maser components were
determined in Sgr B2 Main, 79 in Sgr B2 North, 14 in Sgr B2 Mid-North, and 17
in Sgr B2 South, for a total of 178 water maser positions in Sgr B2.
  The cross calibration scheme of Reid & Menten (1990, 1997) was used. Using
this procedure, high dynamic range continuum images were obtained with accurate
registration (rms ~0.01") of the continuum and maser positions. A detailed
comparison between H II components and maser positions for both Sgr B2 and W49N
is presented. In Sgr B2 Main, the water masers are predominantly located at the
outside edge of the high-frequency continuum, lending support to the proposal
that entrainment by stellar winds may play an important role in water maser
emission.


title: Energy Dissipation in Multi-Phase Infalling Clouds in Galaxy Halos

abstract:
  During the formation of large galaxies, thermal instability leads to the
formation of a population of cool fragments embedded within a background of
tenuous hot gas. The hot gas attains a quasi-hydrostatic equilibrium. Although
the cool clouds are pressure confined by the hot gas, they fall into the
galactic potential, and their motion is subject to drag from the hot gas. The
release of gravitational energy due to the infall of the cool clouds is first
converted into their kinetic energy, and is subsequently dissipated as heat.
The cool clouds therefore represent a potentially significant energy source for
the background hot gas, depending upon the ratio of thermal energy deposited
within the clouds versus the hot gas. In this paper, we show that most of
dissipated energy is deposited in the tenuous hot halo gas, providing a source
of internal energy to replenish losses in the hot gas through bremsstrahlung
emission and conduction into the cool clouds. The heating from the motion of
the cool clouds allows the multi-phase structure of the interstellar medium to
be maintained.


title:
3D MHD Modeling of the Gaseous Structure of the Galaxy: Description of
  the Simulations

abstract:
  The extra stiffness that the magnetic field adds to the ISM changes the way
it reacts to the presence of a spiral perturbation. At intermediate to high z,
the gas shoots up before the arm, flows over, and falls behind it, as it
approaches the next arm. This generates a multicell circulation pattern, within
each of which the net radial mass flux is positive near the midplane and
negative at higher z. The flow distorts the magnetic field lines. In the arm
region, the gas flows nearly parallel to the arm, and therefore, the magnetic
field adopts a similar pitch angle. Between the arms, the gas flows out in
radius, generating a negative pitch angle in the magnetic field. The intensity
and direction of the field yield synthetic synchrotron maps that reproduce some
features of the synchrotron maps of external galaxies, like the islands of
emission and the displacement between the gaseous and synchrotron arms. When
comparing the magnitude of the field with the local gas density, two
distinctive relations appear, depending on whether the magnetic pressure is
dominant. Above the plane, the density structure develops a shape resembling a
breaking wave. This structure collapses and rises again with a period of about
60 Myr, similar to that of a vertical oscillation mode. The falling gas plays
an important part in the overall hydrostatics, since its deceleration
compresses the low z gas, raising the average midplane pressure in the interarm
region above that provided by the weight of the material above.


title:
3D MHD Modeling of the Gaseous Structure of the Galaxy: Synthetic
  Observations

abstract:
  We generated synthetic observations from the four-arm model presented in
Gomez & Cox (2004) for the Galactic ISM in the presence of a spiral
gravitational perturbation. We found that velocity crowding and diffusion have
a strong effect in the l-v diagram. The v-b diagram presents structures at the
expected spiral arm velocities, that can be explained by the off-the-plane
structure of the arms presented in previous papers of this series. Such
structures are observed in the Leiden/Dwingeloo HI survey. The rotation curve,
as measured from the inside of the modeled galaxy, shows similarities with the
observed one for the Milky Way Galaxy, although it has large deviations from
the smooth circular rotation corresponding to the background potential. The
magnetic field inferred from a synthetic synchrotron map shows a largely
circular structure, but with interesting deviations in the midplane due to
distortion of the field from circularity in the interarm regions.


title:
The Cryogenic Refractive Indices of S-FTM16, a Unique Optical Glass for
  Near-Infrared Instruments

abstract:
  The Ohara glass S-FTM16 is of considerable interest for near-infrared optical
designs because it transmits well through the K band and because negative
S-FTM16 elements can be used to accurately achromatize positive calcium
fluoride elements in refractive collimators and cameras. Glass manufacturers
have sophisticated equipment to measure the refractive index at room
temperature, but cannot typically measure the refractive index at cryogenic
temperatures. Near-infrared optics, however, are operated at cryogenic
temperatures to reduce thermal background. Thus we need to know the temperature
dependence of S-FTM16's refractive index. We report here our measurements of
the thermal dependence of S-FTM16's refractive index between room temperature
and ~77 K. Within our measurement errors we find no evidence for a wavelength
dependence or a nonlinear temperature term so our series of measurements can be
reduced to a single number. We find that Delta n_{abs} / Delta T = -2.4x10^{-6}
K^{-1} between 298 K and ~77 K and in the wavelength range 0.6 micron to 2.6
micron. We estimate that the systematic error (which dominates the measurement
error) in our measurement is 10%, sufficiently low for most purposes. We also
find the integrated linear thermal expansion of S-FTM16 between 298 K and 77 K
is -0.00167 m m^{-1}.


title:
The Rotational Excitation Temperature of the $\lambda$6614 Diffuse
  Interstellar Band Carrier

abstract:
  Analysis of high spectral resolution observations of the $\lambda$6614
diffuse interstellar band (DIB) line profile show systematic variations in the
positions of the peaks in the substructure of the profile. These variations --
shown here for the first time -- can be understood most naturally in the
framework of rotational contours of large molecules, where the variations are
caused by changes in the rotational excitation temperature. We show that the
rotational excitation temperature for the DIB carrier is likely significantly
lower than the gas kinetic temperature -- indicating that for this particular
DIB carrier angular momentum buildup is not very efficient.


title:
Is there any evidence for extra-dimensions or quantum gravity effects
  from the delayed MeV-GeV photons in GRB 940217?

abstract:
  The discovery of X-ray afterglows of GRBs, and the identification of host
galaxies of GRBs, confirm the cosmological origin of GRBs. However, the
discovery of the delayed MeV-GeV photons in GRB940217 imposes serious
challenges for the standard emission model of GRB. Although the delayed MeV-GeV
photons might be explained by some radiation emission mechanisms, the mystery
of detecting an 18 GeV photon still remains unsolved. We suggest that the
detection of the 18-GeV photon $ \sim $4500 s after the keV/MeV burst in GRB
940217 provides a strong evidence for the existence of extra-dimensions and/or
quantum gravity effects. The delay scale of the 18-GeV photon leads to an
estimation of the fundamental energy scale, associated with the linear energy
dependence of the speed of light, of the order of $2.1\times 10^{15}$ GeV,
which is consistent with the results obtained by another independent analysis
on the data of OSSE and BATSE.


title:
Constraints on extra-dimensions and variable constants from cosmological
  gamma ray bursts

abstract:
  The observation of the time delay between the soft emission and the
high-energy radiation from cosmological gamma ray bursts can be used as an
important observational test of multi-dimensional physical theories. The main
source of the time delay is the variation of the electromagnetic coupling, due
to dimensional reduction, which induces an energy dependence of the speed of
light. For photons with energies around 1 TeV, the time delay could range from
a few seconds in the case of Kaluza-Klein models to a few days for models with
large extra-dimensions. Based on these results we suggest that the detection of
the 18-GeV photon $ \sim $4500 s after the keV/MeV burst in GRB 940217 provides
a strong evidence for the existence of extra-dimensions. The time delay of
photons, if observed by the next generation of high energy detectors, like, for
example, the SWIFT and GLAST satellite based detectors, or the VERITAS
ground-based TeV gamma-ray instrument, could differentiate between the
different models with extra-dimensions.


title: Mapping Substructures in Dark Matter Halos

abstract:
  We present a detailed study of the real and integrals-of-motion space
distributions of a satellite obtained from a self-consistent high-resolution
simulation of a galaxy cluster and re-simulated using various analytical halo
potentials. We found that the disrupted satellite appears as a coherent
structure in integrals-of-motion space in all models (``live'' and analytical
potential) although the distribution is significantly smeared for the live host
halo. Further the primary mechanism for this smearing is the mass growth of the
host, which changes both the energy and angular momentum of the satellite
debris. Hence, this must be considered when searching for (stellar) streams
with future observational experiments such as RAVE and GAIA.


title: SiO Maser Survey of IRAS Sources in the Inner Galactic Disk

abstract:
  We have surveyed 401 color selected IRAS sources in the Galactic disk in the
SiO J=1--0 v= 1 and 2 maser lines at 43 GHz, resulting in 254 (239 new)
detections. The observed sources lie mostly in a strip of the inner Galactic
disk with boundaries -10<l<40 deg and |b|<3 deg. This survey provides radial
velocities of inner-disk stars for which optical measurements cannot be made
due to interstellar extinction. The SiO $l$--$v$ diagram in the area $-10<l<40
deg exhibits fewer objects coincident with the molecular ring feature than the
OH 1612 MHz source $l$--$v$ map does, indicating a slight difference of stellar
type between SiO and OH emitting stars. After identifying all of the SiO
detected sources in the 2MASS near-infrared catalog, we computed their
luminosity distances based on the infrared fluxes. We then mapped these objects
onto the first quadrant of the Galactic plane. Combining the distances with the
SiO radial-velocities, we obtained a pattern speed for SiO maser sources,
Omega_P=21 (+- 13) km s^{-1} kpc^{-1}, between the distances 1 and 5.5 kpc,
without the use of any dynamical models. The increase of the pattern speed
toward the Galactic center (up to 60 km s^{-1} kpc^{-1} between the distances,
5.5 and 7 kpc) suggests the presence of two pattern speeds in the Galaxy.


title: A first-overtone RR Lyrae star with cyclic period changes

abstract:
  A detailed light curve analysis is presented for a first-overtone RR Lyrae
star, MACHO* J050918.712-695015.31, based on MACHO and OGLE-III observations.
As a foreground object of the Large Magellanic Cloud, it gives an extraordinary
opportunity to study an almost continuous, 12-year long dataset of a relatively
bright (V~15.0 mag) RRc star with rapid period change. Cyclic period modulation
is suggested by the O-C method, where the cycle length is about 8 years. With
the available unique dataset, we could draw strong limits on other light curve
changes that may be associated to the period modulation. We could exclude both
multiple periodicity and amplitude modulation unambiguously. Any theoretical
model should reproduce the observed lack of photometric modulations. Simple
arguments are also given for possible hydromagnetic effects.


title: Phantom thermodynamics

abstract:
  This paper deals with the thermodynamic properties of a phantom field in a
flat Friedmann-Robertson-Walker universe. General expressions for the
temperature and entropy of a general dark-energy field with equation of state
$p=\omega\rho$ are derived from which we have deduced that, whereas the
temperature of a cosmic phantom fluid ($\omega<-1$) is definite negative, its
entropy is always positive. We interpret that result in terms of the intrinsic
quantum nature of the phantom field and apply it to (i) attain a consistent
explanation for some recent results concerning the evolution of black holes
which,induced by accreting phantom energy, gradually loss their mass to finally
vanish exactly at the big rip, and (ii) introduce the concept of cosmological
information and its relation with life and the anthropic principle. Some
quantum statistical-thermodynamic properties of the quantum quantum field are
also considered that include a generalized Wien law and the prediction of some
novel phenomena such as the stimulated absorption of phantom energy and the
anti-laser effect.


title: The 9C Survey: a deeper source count at 15 GHz

abstract:
  Foreground radio sources are a major contaminant for centimetre-wave cosmic
microwave background (CMB) measurements and the 9C survey was set up as part of
the observing strategy of the CMB telescope, the Very Small Array. Prior to
this survey with the Ryle Telescope at 15 GHz there was no comparable
high-frequency radio survey of any extent. Our first published source count
reached a limit of ~25mJy but we have now surveyed some areas more deeply, to a
completenesss limit of ~5mJy. We present the results from this deeper survey.


title: The Multiwavelength Approach to Unidentified Gamma-Ray Sources

abstract:
  As the highest-energy photons, gamma rays have an inherent interest to
astrophysicists and particle physicists studying high-energy, nonthermal
processes. Gamma-ray telescopes complement those at other wavelengths,
especially radio, optical, and X-ray, providing the broad, mutiwavelength
coverage that has become such a powerful aspect of modern astrophysics.
Multiwavelength techniques of various types have been developed to help
identify and explore unidentified gamma-ray sources. This overview summarizes
the ideas behind several of these methods.


title: Avoidance of Big Rip In Phantom Cosmology by Gravitational Back Reaction

abstract:
  The effects of the gravitational back reaction of cosmological perturbations
are investigated in a cosmological model where the universe is dominated by
phantom energy. We assume a COBE normalized spectrum of cosmological
fluctuations at the present time and calculate the effective energy-momentum
tensor of the gravitational back-reactions of cosmological perturbations whose
wavelengths at the time when the back-reactions are evaluated are larger than
the Hubble radius. Our results reveal that the effects of gravitational
back-reactions will counteract that of phantom energy sooner or later and can
become large enough to terminate the phantom dominated phase before the big rip
as the universe evolves. This arises because the phase space of infrared modes
grows very rapidly as we come close to the big rip.


title: Dwarf elliptical galaxies with kinematically decoupled cores

abstract:
  {We present, for the first time, photometric and kinematical evidence,
obtained with FORS2 on the VLT, for the existence of kinematically decoupled
cores (KDCs) in two dwarf elliptical galaxies; FS76 in the NGC5044 group and
FS373 in the NGC3258 group. Both kinematically peculiar subcomponents rotate in
the same sense as the main body of their host galaxy but betray their presence
by a pronounced bump in the rotation velocity profiles at a radius of about 1".
The KDC in FS76 rotates at 10+/-3km/s, with the host galaxy rotating at
15+/-6km/s; the KDC in FS373 has a rotation velocity of 6+/-2km/s while the
galaxy itself rotates at 20+/-5km/s. FS373 has a very complex rotation velocity
profile with the velocity changing sign at 1.5 R_e. The velocity and velocity
dispersion profiles of FS76 are asymmetric at larger radii. This could be
caused by a past gravitational interaction with the giant elliptical NGC5044,
which is at a projected distance of 50kpc. We argue that these decoupled cores
are most likely not produced by mergers in a group or cluster environment
because of the prohibitively large relative velocities. A plausible alternative
is offered by flyby interactions between a dwarf elliptical or its disky
progenitor and a massive galaxy. The tidal forces during an interaction at the
relative velocities and impact parameters typical for a group environment exert
a torque on the dwarf galaxy that, according to analytical estimates, transfers
enough angular momentum to its stellar envelope to explain the observed
peculiar kinematics.


title: A different approach for the estimation of Galactic model parameters

abstract:
  We estimated the Galactic model parameters by means of a new approach based
on the comparison of the observed space density functions per absolute
magnitude interval with a unique density law for each population individually,
and via the procedure in situ for the field SA 114 ($l=68^{o}.15$,
$b=-48^{o}.38$; 4.239 square-degree; J2000). The separation of stars into
different populations has been carried out by their spatial distribution. The
new approach reveals that model parameters are absolute magnitude dependent.
The scale height for thin disk decreases monotonously from absolutely bright to
absolutely faint stars in a range 265-495 pc, but there is a discontunity at
the absolute magnitude $M(g^{'})=10$ where the squared secans hiperbolicus
density law replaces the exponential one. The range of the scale-height for
thick disk, dominant in the absolute magnitude interval $5<M(g^{'})\leq9$, is
less: 805-970 pc. The local space density for thick disk relative to thin disk
decreases from 9.5% to 5.2% when one goes from the absolutely bright to faint
magnitudes. Halo is dominant in three absolute magnitude intervals and the
axial ratio for this component is almost the same for these intervals where
$c/a \sim 0.7$. The same holds for the local space density relative to the thin
disk with range (0.02-0.15)%. The model parameters estimated by comparison of
the observed space density functions combined for three populations per
absolute magnitude interval with the combined density laws agree with the cited
values in the literature. Also each parameter is equal to at least one of the
corresponding parameters estimated for different absolute magnitude intervals
by the new approach. We argue that the most appropriate Galactic model
parameters are those, that are magnitude dependent.


title:
A new Classical T Tauri object at the sub-stellar boundary in Chamaeleon
  II

abstract:
  We have obtained low- and medium-resolution optical spectra of 20 candidate
young low-mass stars and brown dwarfs in the nearby Chamaeleon II dark cloud,
using the Magellan Baade telescope. We analyze these data in conjunction with
near-infrared photometry from the 2-Micron All Sky Survey. We find that one
target, [VCE2001] C41, exhibits broad H(alpha) emission as well as a variety of
forbidden emission lines. These signatures are usually associated with
accretion and outflow in young stars and brown dwarfs. Our spectra of C41 also
reveal LiI in absorption and allow us to derive a spectral type of M5.5 for it.
Therefore, we propose that C41 is a classical T Tauri object near the
sub-stellar boundary. Thirteen other targets in our sample have continuum
spectra without intrinsic absorption or emission features, and are difficult to
characterize. They may be background giants or foreground field stars not
associated with the cloud or embedded protostars, and need further
investigation. The six remaining candidates, with moderate reddening, are
likely to be older field dwarfs, given their spectral types, lack of lithium
and H(alpha).


title: Orbital Parameters of Infalling Dark Matter Substructures

abstract:
  We present distributions of the orbital parameters of dark matter
substructures at the time of merging into their host halo. Accurate knowledge
of the orbits of dark matter substructures is a crucial input to studies which
aim to assess the effects of the cluster environment on galaxies, the heating
of galaxy disks and many other topics. Orbits are measured for satellites in a
large number of N-body simulations. We focus on the distribution of radial and
tangential velocities, but consider also distributions of orbital eccentricity
and semi-major axis. We show that the distribution of radial and tangential
velocities has a simple form and provide a fitting formula for this
distribution. We also search for possible correlations between the infall
directions of pairs of satellites, finding evidence for positive correlation at
small angular separations as expected if some infall occurs along filaments. We
also find (weak) evidence for correlations between the direction of the infall
and infall velocity and the spin of the host halo.


title: The Luminosity and Redshift Distributions of Short-Duration GRB

abstract:
  Using the BATSE peak flux distribution we rederive the short GRBs luminosity
function and compare it with the observed redshift distribution of long bursts.
We show that both distributions are compatible with the assumption that short
as well as long bursts follow the star formation rate. In this case the
difference between the two observed distributions can be interpreted as arising
mostly from differences in the detector's sensitivity to long and short bursts,
while the local rate of short bursts is 0.1 h_70^3 Gpc^-3 yr^-1 . We also
consider the possibility that short GRBs may be associated with binary neutron
star mergers and estimate the effect of the merging time delay on the
luminosity function and redshift distribution. We find that in this case the
local rate of short GRBs is ~0.8 h_70^3 Gpc^-3 yr^-1. Assuming that all binary
merging systems lead to short GRBs, we find a typical jet opening angle of
1.6^o


title: The type Ia supernovae and the Hubble's constant

abstract:
  The Hubble's constant is usually surmised to be a constant; but the
experiments show a large spread and conflicting estimates. According to the
plasma-redshift theory, the Hubble's constant varies with the plasma densities
along the line of sight. It varies then slightly with the direction and the
distance to a supernova and a galaxy. The relation between the magnitudes of
type Ia supernovae and their observed redshifts results in an Hubble's constant
with an average value in intergalactic space of 59.44 km per s per Mpc. The
standard deviation from this average value is only 0.6 km per s per Mpc, but
the standard deviation in a single measurement is about 8.2 km per s per Mpc.
These deviations do not include possible absolute calibration errors. The
experiments show that the Hubble's constant varies with the intrinsic redshifts
of the Milky Way galaxy and the host galaxies for type Ia supernovae, and that
it varies with the galactic latitude. These findings support the
plasma-redshift theory and contradict the contemporary big-bang theory.
Together with the previously reported absence of time dilation in type Ia
supernovae measurements, these findings have profound consequences for the
standard cosmological theory.


title: The spectral evolution of impulsive solar X-ray flares

abstract:
  The time evolution of the spectral index and the non-thermal flux in 24
impulsive solar hard X-ray flares of GOES class M was studied in RHESSI
observations. The high spectral resolution allows for a clean separation of
thermal and non-thermal components in the 10-30 keV range, where most of the
non-thermal photons are emitted. Spectral index and flux can thus be determined
with much better accuracy than before. The spectral soft-hard-soft behavior in
rise-peak-decay phases is discovered not only in the general flare development,
but even more pronounced in subpeaks. An empirically found power-law dependence
between the spectral index and the normalization of the non-thermal flux holds
during the rise and decay phases of the emission peaks. It is still present in
the combined set of all flares. We find an asymmetry in this dependence between
rise and decay phases of the non-thermal emission. There is no delay between
flux peak and spectral index minimum. The soft-hard-soft behavior appears to be
an intrinsic signature of the elementary electron acceleration process.


title: Oscillating Quintom and the Recurrent Universe

abstract:
  Current observations seem to mildly favor an evolving dark energy with the
equation of state getting across -1. This form of dark energy, dubbed Quintom,
is studied phenomenologically in this paper with an oscillating equation of
state. We find oscillating Quintom can unify the early inflation and current
acceleration of the universe, leading to oscillations of the Hubble constant
and a recurring universe. Our oscillating Quintom would not lead to a big
crunch nor big rip. The scale factor keeps increasing from one period to
another and leads naturally to a highly flat universe. The universe in this
model recurs itself and we are only staying among one of the epochs, in which
sense the coincidence problem is reconciled.


title: Radiative Transfer and Starless Cores

abstract:
  We develop a method of analyzing radio frequency spectral line observations
to derive data on the temperature, density, velocity, and molecular abundance
of the emitting gas. The method incorporates a radiative transfer code with a
new technique for handling overlapping hyperfine emission lines within the
accelerated lambda iteration algorithm and a heuristic search algorithm based
on simulated annnealing. We apply this method to new observations of N_2H^+ in
three Lynds clouds thought to be starless cores in the first stages of star
formation and determine their density structure. A comparison of the gas
densities derived from the molecular line emission and the millimeter dust
emission suggests that the required dust mass opacity is about
kappa_{1.3mm}=0.04 cm^2/g, consistent with models of dust grains that have
opacities enhanced by ice mantles and fluffy aggregrates.


title: Secular Evolution and the Growth of Pseudobulges in Disk Galaxies

abstract:
  Galaxy evolution is in transition from an early universe dominated by
hierarchical clustering to a future dominated by secular processes. These
result from interactions involving collective phenomena such as bars, oval
disks, spiral structure, and triaxial dark halos. This paper summarizes a
review by Kormendy & Kennicutt (2004) using, in part, illustrations of
different galaxies. In simulations, bars rearrange disk gas into outer rings,
inner rings, and galactic centers, where high gas densities feed starbursts.
Consistent with this picture, many barred and oval galaxies have dense central
concentrations of gas and star formation rates that can build bulge-like
stellar densities on timescales of a few billion years. We conclude that
secular evolution builds dense central components in disk galaxies that look
like classical, merger-built bulges but that were made slowly out of disk gas.
We call these pseudobulges. Many pseudobulges can be recognized because they
have characteristics of disks: (1) flatter shapes than those of classical
bulges, (2) correspondingly large ratios of ordered to random velocities, (3)
small velocity dispersions, (4) spiral structure or nuclear bars, (5) nearly
exponential brightness profiles, and (6) starbursts. These structures occur
preferentially in barred and oval galaxies in which secular evolution should be
most rapid. Thus a variety of observational and theoretical results contribute
to a new paradigm of secular evolution that complements hierarchical
clustering.


title: Direct Extragalactic Distance Determination Using X-Ray Scattering

abstract:
  We examine the feasibility of using dust-scattered X-rays for direct
determination of distances to nearby galaxies with bright background AGNs,
QSOs, or GRBs. We show how the Chandra X-Ray Observatory could be used to
determine the distance to M31 to an unprecedented absolute accuracy of 1%.


title: Cosmological constraints from a 2D SZ catalog

abstract:
  We perform a Fisher matrix analysis to quantify cosmological constraints
obtainable from a 2-dimensional Sunyaev-Zel'dovich (SZ) cluster catalog using
the counts and the angular correlation function. Three kinds of SZ survey are
considered: the almost all-sky Planck survey and two deeper ground-based
surveys, one with 10% sky coverage, the other one with a coverage of 250 square
degrees. With the counts and angular function, and adding the constraint from
the local X-ray cluster temperature function, joint 10% to 30% errors (1 sigma)
are achievable on the cosmological parameter pair (sigma_8, Omega_m) in the
flat concordance model. Constraints from a 2D distribution remain relatively
robust to uncertainties in possible cluster gas evolution for the case of
Planck. Alternatively, we examine constraints on cluster gas physics when
assuming priors on the cosmological parameters (e.g., from cosmic microwave
background anisotropies and SNIa data), finding a poor ability to constrain gas
evolution with the 2-dimensional catalog. From just the SZ counts and angular
correlation function we obtain, however, a constraint on the product between
the present-day cluster gas mass fraction and the normalization of the
mass-temperature relation, T_*, with a precision of 15%. This is particularly
interesting because it would be based on a very large catalog and is
independent of any X-ray data.


title: Can We See Lorentz-Violating Vector Fields in the CMB?

abstract:
  We investigate the perturbation theory of a fixed-norm, timelike
Lorentz-violating vector field. After consistently quantizing the vector field
to put constraints on its parameters, we compute the primordial spectra of
perturbations generated by inflation in the presence of this vector field. We
find that its perturbations are sourced by the perturbations of the inflaton;
without the inflaton perturbation the vector field perturbations decay away
leaving no primordial spectra of perturbations. Since the inflaton perturbation
does not have a spin-1 component, the vector field generically does not
generate any spin-1 ``vector-type'' perturbations. Nevertheless, it will modify
the amplitude of both the spin-0 ``scalar-type'' and spin-2 ``tensor-type''
perturbation spectra, leading to violations of the inflationary consistency
relationship.


title:
The Nature of Nearby Counterparts to Intermediate Redshift Luminous
  Compact Blue Galaxies I. Optical/H I Properties and Dynamical Masses

abstract:
  We present single-dish H I spectra obtained with the Green Bank Telescope,
along with optical photometric properties from the Sloan Digital Sky Survey, of
20 nearby (D < 70 Mpc) Luminous Compact Blue Galaxies (LCBGs). These ~L*, blue,
high surface brightness, starbursting galaxies were selected with the same
criteria used to define LCBGs at higher redshifts. We find these galaxies are
gas-rich, with M(HI) ranging from 5*10^8 to 8*10^9 M_sun, and M(HI)/L_B ranging
from 0.2 to 2 M_sun/L_sun, consistent with a variety of morphological types of
galaxies. We find the dynamical masses (measured within R_25) span a wide
range, from 3*10^9 to 1*10^11 M_sun. However, at least half have dynamical
mass-to-light ratios smaller than nearby galaxies of all Hubble types, as found
for LCBGs at intermediate redshifts. By comparing line widths and effective
radii with local galaxy populations, we find that LCBGs are consistent with the
dynamical mass properties of Magellanic (low luminosity) spirals, and the more
massive irregulars and dwarf ellipticals, such as NGC 205.


title:
The line-of-sight towards GRB 030429 at z = 2.66: Probing the matter at
  stellar, galactic and intergalactic scales

abstract:
  We report the discovery of the optical afterglow (OA) of the long-duration
gamma-ray burst GRB 030429, and present a comprehensive optical/near-infrared
dataset used to probe the matter at different distance scales, i.e. in the
burst environment, in the host galaxy and in an intervening absorber. A break
in the afterglow light curve is seen approximately 1 day from the onset of the
burst. The light curve displays a significant deviation from a simple broken
power-law with a bright 1.5 magnitude bump with a duration of 2-3 days. The
optical/near-infrared spectral energy distribution is best fit with a power-law
with index beta = -0.36 +/- 0.12 reddened by an SMC-like extinction law with (a
modest) A_V = 0.34 +/- 0.04. In addition, we present deep spectroscopic
observations obtained with the Very Large Telescope. The redshift measured via
metal absorption lines in the OA is z = 2.658 +/- 0.004. Based on the damped
Ly-alpha absorption line in the OA spectrum we measure the HI column density to
be log N(HI) = 21.6 +/- 0.2. This confirms the trend that GRBs tend to be
located behind very large HI column densities. The resulting dust-to-gas ratio
is consistent with that found in the SMC, indicating a low metallicity and/or a
low dust-to-metal ratio in the burst environment. We find that a neighbouring
galaxy, at a separation of only 1.2", has z = 0.841 +/- 0.001, ruling it out as
the host of GRB 030429. The small impact parameter of this nearby galaxy, which
is responsible for MgII absorption in the OA spectrum, is in contrast to
previous identifications of most QSO absorption-selected galaxy counterparts.
Finally, we demonstrate that the OA was not affected by strong gravitational
lensing via the nearby galaxy.


title: Stability of primordial black holes

abstract:
  Vacuum polarization in a strong field, such as Hawking radiation from black
holes, is constrained by the directional metric of strong field vectors.
Relative localization of the quanta and the Schwarzschild radius is examined.
Concept of thermal equilibrium of excited vacuum is critically analyzed and
judged as dis-equilibrium, because virtual modes or particles are mutually
independent. The result shows that primordial micro-size black holes (\pmbhs)
cannot produce much Hawking radiation via fermions, bosons or thermal photons.
Primordial black holes produced in the early epoch of the Big Bang should be
very stable over Hubble time and consequently, may constitute a significant
part of the cold dark matter in the structural formation of the universe.
\pmbhs should be gravitationally highly-condensed as missing mass around
galaxies and galaxy clusters, and remain very difficult to observe.


title: The GJ 876 Planetary System -- A Progress Report

abstract:
  We present an updated analysis of the GJ 876 planetary system based on an
augmented data set that incorporates 65 new high-precision radial velocities
obtained with the Keck telescope from 2001 to 2004. These new radial velocities
permit a more accurate characterization of the planet-planet interactions
exhibited by the system. Self-consistent three-body orbital fits (which
incorporate both the estimated instrumental uncertainties and 6 m/s Gaussian
stellar jitter) continue to show that GJ 876 b and GJ 876 c are participating
in a stable and symmetric 2:1 resonance condition in which the lowest order,
eccentricity type mean-motion resonance variables are all librating. The
planets are also locked in a secular resonance which causes them to librate
about apsidal alignment. The small libration widths of all three resonances
likely point to a dissipative history of differential migration for the two
planets in the system. (for full abstract see paper).


title:
Jet break time -- flux density relationship and constraints on physical
  parameters of GRB afterglows

abstract:
  We derive a relation between the flux density $F_{\nu,j}$ at the light-curve
break of a gamma-ray burst (GRB) afterglow and the break time $t_{j}$. The
break is due to the transition from the spherical-like to jet-like evolution of
the afterglow, when the Lorentz factor of the jet equals the inverse of the
initial half-opening angle, i.e., $\gamma=1/\theta_0$. We show that this
relation indeed behaves as $F_{\nu,j}\propto t_{j}^{-p}$ among GRBs for the
slow-cooling case, where $p$ is the power-law index of electron distribution. A
statistical analysis of the optical jet breaks of nine GRBs gives $p=2.10\pm
0.21$, which is consistent with the shock acceleration theory. The value of $p$
derived in this way is different from the observed temporal index $\alpha_2$
($F_{\nu}\propto t^{-\alpha_{2}}$) of the late-time light curve after $t_{j}$,
which suffers several uncertainties from the unclear hydrodynamics of the
sideways expansion and exhibits a large dispersion. Our results not only
confirm that the remnants of GRBs are standard candles, but also provide the
first evidence that the physical parameters of relativistic shocks are
universal, with the favored values $\epsilon_{e}\sim 0.1$ and $\epsilon_{B}\sim
10^{-3}$.


title:
Testing the Predictions of the Universal-Structured Jet Model of
  Gamma-Ray Bursts by Simulations

abstract:
  Based on the standard energy reservoir of gamma-ray burst (GRB) jets and the
relationship between peak energy ($E_p$) of $\nu F_{\nu}$ spectrum and the
equivalent-isotropic energy ($E_{\rm{iso}}$), we test the GRB probability
distributions as a function of viewing angle ($\theta$) and of viewing angle
together with redshift $z$, $P(\theta)$ and $P(\theta,z)$, predicted by the
universal-structured jet (USJ) model with simulations on observational bases
for a detection threshold of $S>4 \times 10^{-5}$ erg cm$^{-2}$, where $S$ is
the total fluence in an energy band $>20$ keV. We simulate a sample including
$10^{6}$ GRBs, and then derive $P(\theta)$ and $P(\theta,z)$. We show that both
simulated and theoretical $P(\theta)$ and $P(\theta,z)$ are consistent with
each other. This consistency seems to be regarded as support for the USJ model.
A small difference between the theoretical and simulated results might be due
to the observed $E_p$ distribution used in our simulations, which perhaps
suffers a little of biases for $E_p<100$ keV.


title:
The distance to the Leo I dwarf spheroidal galaxy from the Red Giant
  Branch Tip

abstract:
  We present V and I photometry of a 9.4 arcmin X 9.4 arcmin field centered on
the dwarf spheroidal galaxy Leo I. The I magnitude of the tip of the Red Giant
Branch is robustly estimated from two different datasets (I^{TRGB}=17.97
+0.05/-0.03). From this estimate, adopting [M/H]=-1.2 from the comparison of
RGB stars with Galactic templates, we obtain a distance modulus (m-M)_0=22.02
+/- 0.13, corresponding to a distance D=254 +16/-19 Kpc.