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arxiv_abstracts_gfissore | 2,001 | Polarized Microwave Radiation from Dust
Observations of cosmic microwave background in the range 10-90 GHz have
revealed an anomalous foreground component well correlated with 12 , 60
and 100 emission from interstellar dust. As the recent
cross-correlation analysis of WHAM H maps with the Tenerife 10 and 15 GHz
maps ... | 235 | academic |
arxiv_abstracts_gfissore | 2,001 | Population clustering as a signal for deconfinement in accreting compact
stars
We study the evolution of the rotation frequency for accreting compact stars.
The discontinuous change of the moment of inertia of a rapidly rotating star
due to the possible quark core appearance entails a characteristic change in
the spi... | 223 | academic |
arxiv_abstracts_gfissore | 2,001 | HI observations of luminous infrared galaxy mergers
A total of 19 luminous infrared galaxy mergers, with L_IR 2 10^11 L_sun for
H_0=75 km/s/Mpc, have been observed in the HI line at Nancay and four of them
were observed at Arecibo as well. Of these 19, ten had not been observed
before. Six were clearly detected, one o... | 130 | academic |
arxiv_abstracts_gfissore | 2,001 | The Bell Laboratories (13)CO Survey: Longitude-Velocity Maps
A survey is presented of the Galactic plane in the J=1-0 transition of
(13)CO. About 73,000 spectra were obtained with the 7 m telescope at Bell
Laboratories over a ten-year period. The coverage of survey is (l, b) = (-5 to
117, -1 to +1), or 244 square degr... | 295 | academic |
arxiv_abstracts_gfissore | 2,001 | The Lyman-Alpha Forest at 1.5 < z < 4
Using high resolution (R 45000), high S/N (20-50) VLT/UVES observations
covering the Lyman-alpha forest at 1.5 < z < 2.4 combined with similar
observations at z > 2.4 from the literature, we have presented the redshift
evolution of the Lyman-alpha forest at 1.5 < z < 4. We applied... | 391 | academic |
arxiv_abstracts_gfissore | 2,001 | Ultra Efficient Internal Shocks
Gamma-ray bursts are believed to originate from internal shocks which arise
in an irregular relativistic wind. The process has been thought to be
inefficient, converting only a few percent of the kinetic energy into
gamma-rays. We define ultra efficient internal shocks as those in which... | 207 | academic |
arxiv_abstracts_gfissore | 2,001 | Supernova, Hypernova and Gamma Ray Bursts
Recent observations suggest that gamma ray bursts (GRBs) and their afterglows
are produced by highly relativistic jets emitted in core collapse supernova
explosions (SNe). The result of the event, probably, is not just a compact
object plus a spherical ejecta: within days, a f... | 320 | academic |
arxiv_abstracts_gfissore | 2,001 | Plasmoid-Induced-Reconnection and Fractal Reconnection
As a key to undertanding the basic mechanism for fast reconnection in solar
flares, plasmoid-induced-reconnection and fractal reconnection are proposed and
examined. We first briefly summarize recent solar observations that give us
hints on the role of plasmoid (f... | 399 | academic |
arxiv_abstracts_gfissore | 2,001 | Cosmological Perturbation Theory and Structure Formation
These lecture notes discuss several topics in the physics of cosmic structure
formation starting from the evolution of small-amplitude fluctuations in the
radiation-dominated era. The topics include relativistic cosmological
perturbation theory with the scalar-v... | 115 | academic |
arxiv_abstracts_gfissore | 2,001 | Jet- and Wind-Driven Ionized Outflows in the Superbubble and
Star-Forming Disk of NGC 3079
HST WFPC2 images are presented that span the inner 19 kpc diameter of the
edge-on spiral galaxy NGC 3079; they are combined with ground-based Halpha+[N
II] Fabry-Perot spectra and VLA images of radio polarization vectors and
ro... | 415 | academic |
arxiv_abstracts_gfissore | 2,001 | The birth of strange stars and their dynamo-originated magnetic fields
It is shown that protostrange stars (PSSs) can be convective and that there
are two possible scenarios describing their turbulence. Besides the local
turbulence on the scale which is less than the mean free path of neutrinos,
large-scale ( 1 km) co... | 199 | academic |
arxiv_abstracts_gfissore | 2,001 | A Further Study of Relative longitude shift of Pulsar Beams
It is of great important to study pulsar beam shapes if we are concerned with
emission theories and pulsar birth rate. Both observations and/or the inverse
Compton scattering model show that different emission components are emitted
from different heights. Th... | 132 | academic |
arxiv_abstracts_gfissore | 2,001 | The fastest rotating pulsar: A strange star?
According to the observational limits on the radius and mass, the fastest
rotating pulsar (PSR 1937+21) is probably a strange star, or at least some
neutron star equations of state should be ruled out, if we suggest that a
dipole magnetic field is relevant to its radio emis... | 103 | academic |
arxiv_abstracts_gfissore | 2,001 | Attractors and Isocurvature Perturbations in Quintessence Models
We investigate the evolution of cosmological perturbations in scenarios with
a quintessence scalar field, both analytically and numerically. In the tracking
regime for quintessence, we find the long wavelength solutions for
quintessential perturbations. ... | 96 | academic |
arxiv_abstracts_gfissore | 2,001 | Adaptive optics at the WHT
The WHT is unusually well-placed for exploitation of adaptive-optics (AO)
technology. The site seeing is excellent (median 0.7 arcsec), dome seeing is
negligible, and preliminary studies indicate that most of the atmospheric
seeing originates in a well-defined layer at low altitude, which bo... | 226 | academic |
arxiv_abstracts_gfissore | 2,001 | Scalar field models for an accelerating universe
I describe a new class of quintessence+CDM models in which late time scalar
field oscillations can give rise to both quintessence and cold dark matter.
Additionally, a versatile ansatz for the luminosity distance is used to
reconstruct the quintessence equation of state... | 83 | academic |
arxiv_abstracts_gfissore | 2,001 | Relativistic Outflows from Advection-Dominated Accretion Disks around
Black Holes
The Newtonian ADAF model has been generalized recently to obtain the ADIOS
model that includes outflows of energy and angular momentum. The utilization of
a Newtonian gravitational potential limits the ability of the ADIOS model to
desc... | 224 | academic |
arxiv_abstracts_gfissore | 2,001 | Science Prospects for SPI
After the recent beautiful results on gamma-ray lines obtained with CGRO, the
INTEGRAL mission with the imaging-spectrometer SPI will set the next milestone,
combining improved sensitivity and angular resolution with a considerable
increase in spectral resolution. SPI is expected to provide s... | 400 | academic |
arxiv_abstracts_gfissore | 2,001 | Chandra Observations of the Gravitationally Lensed System 2016+112
An observation of the gravitationally lensed system 2016+112 with the Chandra
X-ray Observatory has resolved a mystery regarding the proposed presence of a
dark matter object in the lens plane of this system. The Chandra ACIS
observation has clearly de... | 397 | academic |
arxiv_abstracts_gfissore | 2,001 | Exact Expressions for the Critical Mach Numbers in the Two-Fluid Model
of Cosmic-Ray Modified Shocks
The acceleration of relativistic particles due to repeated scattering across
a shock wave remains the most attractive model for the production of energetic
cosmic rays. This process has been analyzed extensively durin... | 273 | academic |
arxiv_abstracts_gfissore | 2,001 | A New Very Cool White Dwarf Discovered by the Sloan Digital Sky Survey
Early data taken during commissioning of the SDSS have resulted in the
discovery of a very cool white dwarf. It appears to have stronger collision
induced absorption from molecular hydrogen than any other known white dwarf,
suggesting it has a cool... | 164 | academic |
arxiv_abstracts_gfissore | 2,001 | Possible Strong Gravitational Wave Sources for the LISA Antenna
Recently Fuller & Shi proposed that the gravitational collapse of
supermassive objects ( M 10^4M_ ) could be a cosmological source
of -ray bursts (GRBs). The major advantage of their model is that
supermassive object collapses are far more energetic than ... | 246 | academic |
arxiv_abstracts_gfissore | 2,001 | Evidence for Extinction and Accretion Variability in T Tau S
We present angularly resolved spectra of T Tau North and South in the 3
micron water ice feature and K-band. Most of the water ice absorption lies
along the line of sight toward T Tau South, confirming that it is viewed
through stronger extinction. A decreas... | 192 | academic |
arxiv_abstracts_gfissore | 2,001 | Theory of Extrasolar Giant Planet Transits
We present a synthesis of physical effects influencing the observed
lightcurve of an extrasolar giant planet (EGP) transiting its host star. The
synthesis includes a treatment of Rayleigh scattering, cloud scattering,
refraction, and molecular absorption of starlight in the E... | 180 | academic |
arxiv_abstracts_gfissore | 2,001 | Spatial/Spectral Resolution of a Galactic Bulge K3 Giant Stellar
Atmosphere via Gravitational Microlensing
We present two Keck HIRES spectra (R=40,000) of a bulge K3 giant taken on
successive nights during the second caustic crossing of the binary microlensing
event EROS BLG-2000-5. This caustic crossing served to ef... | 267 | academic |
arxiv_abstracts_gfissore | 2,001 | The early X-ray emission from V382 Velorum (=Nova Vel 1999): An internal
shock model
We present the results of ASCA and RXTE observations of the early X-ray
emission from the classical nova V382 Velorum. Its ASCA spectrum was hard
(kT 10 keV) with a strong (10**23 cm**-2) intrinsic absorption. In the
subsequent RXTE ... | 180 | academic |
arxiv_abstracts_gfissore | 2,001 | Oscillator Strengths for B-X, C-X, and E-X Transitions in Carbon
Monoxide
Band oscillator strengths for electronic transitions in CO were obtained at
the Synchrotron Radiation Center of the University of Wisconsin-Madison. Our
focus was on transitions that are observed in interstellar spectra with the Far
Ultraviolet... | 297 | academic |
arxiv_abstracts_gfissore | 2,001 | A massive reservoir of low-excitation molecular gas at high redshift
Molecular hydrogen is an important component of galaxies because it fuels
star formation and accretion onto AGN, the two processes that generate the
large infrared luminosities of gas-rich galaxies. Observations of spectral-line
emission from the tra... | 330 | academic |
arxiv_abstracts_gfissore | 2,001 | Galactic Chemical Abundances at z>3 I: First Results from the Echellette
Spectrograph and Imager
We present the first results from an ongoing survey to discover and measure
the metallicity of z>3 damped Lya systems with the Echellette Spectrograph and
Imager (ESI) on the Keck II telescope. Our motivation arises from ... | 295 | academic |
arxiv_abstracts_gfissore | 2,001 | How to focus a Cherenkov telescope
Cherenkov telescopes image the Cherenkov emission from air showers. A priori,
it is not obvious if the `best' images are achieved by measuring Cherenkov
photon angles, i.e. focusing the telescope at infinity, or by considering the
air shower as an object to be imaged, in which case o... | 102 | academic |
arxiv_abstracts_gfissore | 2,001 | Evolution of Isolated Neutron Stars
In this paper we briefly review our recent results on evolution and
properties of isolated neutron stars (INSs) in the Galaxy.
As the first step we discuss stochastic period evolution of INSs. We briefly
discuss how an INS's spin period evolves under influence of interaction with
t... | 277 | academic |
arxiv_abstracts_gfissore | 2,001 | Oxygen in the Very Early Galaxy
Oxygen abundances in a sample of ultra-metal-poor subdwarfs have been derived
from measurements of the oxygen triplet at 7771--5 A and OH lines in the near
UV performed in high-resolution and high signal-to-noise spectra obtained with
WHT/UES, KeckI/HIRES, and VLT/UVES. Our Fe abundance... | 335 | academic |
arxiv_abstracts_gfissore | 2,001 | New emission phase of the Be/X-ray binary X Persei: nearly simultaneous
spectroscopic and near-infrared observations
We present a series of optical spectroscopic and near-infrared photometric
observations of the Be star X Persei, from the beginning of the recent emission
phase. Our data show that after the latest ext... | 310 | academic |
arxiv_abstracts_gfissore | 2,001 | The VIRMOS-VLT Deep Survey
The aim of the VIRMOS VLT Deep Survey (VVDS) is to study of the evolution of
galaxies, large scale structures and AGNs from a sample of more than 150,000
galaxies with measured redshifts in the range 0<z<5+. The VVDS will rely on the
VIMOS and NIRMOS wide field multi-object spectrographs, wh... | 278 | academic |
arxiv_abstracts_gfissore | 2,001 | Flat-Fielding BATSE Occultation Data for use in a Hard X-Ray All Sky
Survey
The BATSE mission aboard CGRO can be used to observe hard X-ray sources by
using the Earth occultation method. This method relies on measuring a step in
the count rate profile in each BATSE detector as a source rises above or sets
below the E... | 240 | academic |
arxiv_abstracts_gfissore | 2,001 | GRBS: Standard Model & Beyond
There have been great and rapid progresses in the field of -ray
bursts since BeppoSAX and other telescopes discovered their afterglows in 1997.
In this talk, the main observational facts of -ray bursts and their
afterglows, and the standard fireball shock model are reviewed briefly. And
t... | 93 | academic |
arxiv_abstracts_gfissore | 2,001 | STIS Echelle Observations of the Seyfert Galaxy NGC 4151: Physical
Conditions in the Ultraviolet Absorbers
We have examined the physical conditions in intrinsic UV-absorbing gas in the
Seyfert galaxy NGC 4151, using echelle spectra obtained with the Space
Telescope Imaging Spectrograph (STIS). We confirm the presence... | 429 | academic |
arxiv_abstracts_gfissore | 2,001 | Mid-infrared observations of NGC 1068 with ISOCAM
We report on Mid-Infrared (MIR) observations of the Seyfert 2 galaxy NGC
1068, obtained with ISOCAM in low-resolution spectro-imaging mode. The spatial
resolution (around 5 arcsec) allows us to disentangle the circumnuclear
starburst regions from the emission of the ac... | 374 | academic |
arxiv_abstracts_gfissore | 2,001 | Gamma Ray Pulsars: Observations
High-energy gamma rays are a valuable tool for studying particle acceleration
and radiation in the magnetospheres of energetic pulsars. The six or more
pulsars seen by CGRO/EGRET show that: the light curves usually have double-peak
structures (suggesting a broad cone of emission); gamma... | 196 | academic |
arxiv_abstracts_gfissore | 2,001 | Measuring Time-Dependence of Dark Energy Density from Type Ia Supernova
Data
Observations of high redshift supernovae imply an accelerating Universe which
can only be explained by an unusual energy component such as vacuum energy or
quintessence. To assess the ability of current and future supernova data to
constrain... | 331 | academic |
arxiv_abstracts_gfissore | 2,001 | Application of an objective method for the identification of Young Star
Groupings in spiral galaxies
We present some results of the application of our automatic technique for the
identification of Young Star Groupings (YSGs) in spiral galaxies. In this
report we discuss our new results for NGC 3377a and NGC 3507 toge... | 140 | academic |
arxiv_abstracts_gfissore | 2,001 | Secular Bar-Mode Evolution and Gravitational Waves From Neutron Stars
The secular instability and nonlinear evolution of the m=2 f-mode (bar-mode)
driven by gravitational radiation reaction in a rapidly rotating, newly formed
neutron star are reviewed. There are two types of rotating bars which generate
quite differen... | 157 | academic |
arxiv_abstracts_gfissore | 2,001 | Young Supernova Remnants: Issues and Prospects
After reviewing recent work on the dynamics of young supernova remnants
(YSNRs) and discussing how YSNRs can be used as physics laboratories, I discuss
several challenges: Where are the very young SNRs in the Galaxy? Can very young
SNRs produce gamma ray bursts? The Conne... | 98 | academic |
arxiv_abstracts_gfissore | 2,001 | A Doppler Shift model to explain the Cyclotron Line Variability in X-Ray
Pulsars
A simple model to explain the phase-dependence of the cyclotron absorption
line observed in many X-Ray pulsars is presented. It includes several
relativistic effects, namely gravitational redshift, gravitational light
deflection, and - m... | 159 | academic |
arxiv_abstracts_gfissore | 2,001 | Evidence for a Sudden Magnetic Field Reconfiguration in SGR 1900+14
We report the detection of large flux changes in the persistent X-ray flux of
SGR 1900+14 during its burst active episode in 1998. Most notably, we find a
factor 700 increase in the non-burst X-ray flux following the August 27th
flare, which decayed i... | 230 | academic |
arxiv_abstracts_gfissore | 2,001 | Summary: Modes of Star Formation
This contribution summarizes briefly the main topics covered at this
wide-ranging conference. Much of the evidence presented indicates that star
formation occurs in discrete episodes or bursts that produce stellar groupings
of all sizes, the fossil remnants of which make up the present... | 64 | academic |
arxiv_abstracts_gfissore | 2,001 | Event Rates for Binary Inspiral
Double compact objects (neutron stars and black holes) found in binaries with
small orbital separations are known to spiral in and are expected to coalesce
eventually because of the emission of gravitational waves. Such inspiral and
merger events are thought to be primary sources for gr... | 163 | academic |
arxiv_abstracts_gfissore | 2,001 | KiloHertz QPO and Gravitational Wave Emission as the Signature of the
Rotation and Precession of a LMXB Neutron Star Near Breakup
The basic theory of torque free precession (TFP) of the outer crust of a
neutron star (NS) as the signature of the approach to NS breakup is a viable
explanation of the uniform properties ... | 399 | academic |
arxiv_abstracts_gfissore | 2,001 | Evidence for Expanding Superbubbles in a Galaxy at z=0.7443
The intervening z=0.7443 Mg II absorption system in the spectrum of MC
1331+170 shows an unusual series of line pairs, each with velocity separations
of 30 km/s. These lines could be explained as the shells of expanding
superbubbles residing in the outer regi... | 263 | academic |
arxiv_abstracts_gfissore | 2,001 | NGC 3065: A Certified LINER With Broad, Variable Balmer Lines
Motivated by the X-ray properties of the galaxy NGC 3065, we have obtained
new optical spectra which reveal that it has a low-ionization nuclear
emission-line region (LINER) as well as broad Balmer emission lines,
establishing it as an active galactic nucle... | 381 | academic |
arxiv_abstracts_gfissore | 2,001 | AGN Population at 10^-13 erg s-1 cm-2: Results from Optical
Identification of ASCA Surveys
In this paper, results of optical identification of ASCA surveys are
summarized. To understand luminous AGNs in the z<1 universe, the ASCA AGN
sample is still better than samples of AGNs from deep Chandra or XMM-Newton
surveys.... | 236 | academic |
arxiv_abstracts_gfissore | 2,001 | Spatially resolved spectroscopy of Cassiopeia A with MECS on board
BeppoSAX
We have performed the first detailed spatially resolved spectroscopy of Cas A
in the 1.6-10 keV energy range, using data taken with the MECS spectrometer on
board the BeppoSAX Observatory. We performed a spatial deconvolution of the
data and ... | 388 | academic |
arxiv_abstracts_gfissore | 2,001 | Mechanisms and sites of ultra high energy cosmic ray origin
We shortly discuss several astrophysical scenarios leading to cosmic ray
acceleration up to extremely high energies reaching the scale of 10^20 eV.
The processes suggested in the literature include acceleration at relativistic
jet terminal shocks and shear bo... | 201 | academic |
arxiv_abstracts_gfissore | 2,001 | Spectroscopy of Stellar Jets, Outflows, and Young Stellar Objects with
the Infrared Space Observatory
The Infrared Space Observatory (ISO) was an extremely successful european
space mission that gave us an unparallel view of the Universe in the infrared,
and provided us with hundreds of observations of star forming r... | 229 | academic |
arxiv_abstracts_gfissore | 2,001 | Are mirror planets opaque?
Over the last few years, many close orbiting ( 0.05 A.U.) large mass
planets ( M_J ) of nearby stars have been discovered. Their existence
has been inferred from tiny Doppler shifts in the light from the star and in
one case a transit has been observed. Because ordinary planets are not expec... | 300 | academic |
arxiv_abstracts_gfissore | 2,001 | Entropic-acoustic instability of shocked Bondi accretion I. What does
perturbed Bondi accretion sound like ?
In the radial flow of gas into a black hole (i.e. Bondi accretion), the
infall of any entropy or vorticity perturbation produces acoustic waves
propagating outward. The dependence of this acoustic flux on the ... | 406 | academic |
arxiv_abstracts_gfissore | 2,001 | BeppoSAX spectroscopy of the luminous X-ray sources in M33
The nearby galaxy M33 was observed by the imaging X-ray instruments on-board
BeppoSAX. Two observations at different phases of the 105.9 day intensity cycle
of the luminous central source X-8 failed to reveal the expected modulation,
suggesting that it is prob... | 396 | academic |
arxiv_abstracts_gfissore | 2,001 | Lensing Constraints on the Cores of Massive Dark Matter Halos
The statistics of wide-separation (6'' < theta < 15'') gravitational lenses
constrain the amount of mass in the cores of dark matter halos on group and
cluster mass scales. For a family of halo models with a central cusp
r^-alpha (1.0 <= alpha <= 1.9), th... | 189 | academic |
arxiv_abstracts_gfissore | 2,001 | Evidence for Residual Material in Accretion Disk Gaps: CO Fundamental
Emission from the T Tauri Spectroscopic Binary DQ Tau
We present the discovery of CO fundamental ro-vibrational emission from the
classical T Tauri spectroscopic binary DQ Tau. The high-resolution infrared
echelle spectra reveal emission lines from... | 324 | academic |
arxiv_abstracts_gfissore | 2,001 | BeppoSAX observation of the rich cluster of galaxies Abell 85
We report the observation of the Intra-Cluster Medium (ICM) of Abell 85 by
the X-ray satellite BeppoSAX. We have both analysed the spectrum obtained in
the central 8 arcmin circular region centred on the Very Steep Spectrum Radio
Source (VSSRS) and the spec... | 379 | academic |
arxiv_abstracts_gfissore | 2,001 | The First Turbulence
Chaotic, eddy-like motions dominated by inertial-vortex forces begin
immediately at Planck scales in a hot big-bang cosmological model. This
quantum-gravitational-dynamics epoch produced not only the first
space-time-energy of the universe but the first large Reynolds number
turbulence and turbule... | 272 | academic |
arxiv_abstracts_gfissore | 2,001 | Intrinsic Absorption in Radio-Selected QSOs
Moderate resolution spectra have been recorded for a sample of radio-selected
QSOs (z=2.5) discovered in the ``Faint Images of the Radio Sky at Twenty
centimeters'' (FIRST) VLA survey. This work is motivated by the study of a
heterogeneous set of QSO absorption line spectra ... | 300 | academic |
arxiv_abstracts_gfissore | 2,001 | Quasar Absorption Lines as a Function of Quasar Orientation Measures
We present high resolution radio data at 3.5 and 20 cm from the VLA in the A
configuration for 144 quasars with known CIV absorption line properties. Using
these measurements, we compare and contrast a number of quasar orientation
indicators. These q... | 209 | academic |
arxiv_abstracts_gfissore | 2,001 | Deep imaging of Q2112+059: A bright host galaxy but no DLA absorber
In a ongoing programme aimed at studying galaxy counterparts of Damped
Ly-alpha Absorbers (DLAs) we have obtained high resolution deep I-band imaging
data of the field around the z_em = 0.457 BAL QSO Q2112+059. In the literature
this QSO is listed to ... | 374 | academic |
arxiv_abstracts_gfissore | 2,001 | Revealing the Dusty Warm Absorber in MCG--6-30-15 with the Chandra HETG
We present detailed evidence for a warm absorber in the Seyfert 1 galaxy
MCG--6-30-15 and dispute earlier claims for relativistic O line emission. The
HETG spectra show numerous narrow, unresolved (FWHM < 200 km/s) absorption
lines from a wide ran... | 443 | academic |
arxiv_abstracts_gfissore | 2,001 | X-ray energy and power spectra of Seyfert 1 and Narrow Line Seyfert 1
galaxies: comparison to Black Hole Binaries
I review observational data on X-ray energy spectra and variability of
Seyfert 1 and Narrow Line Seyfert 1 galaxies, and compare them to black hole
binary (BHB) systems. There seems to be greater similari... | 232 | academic |
arxiv_abstracts_gfissore | 2,001 | The Postcollapse Equilibrium Structure of Cosmological Haloes in a
Low-Density Universe
An analytical model is presented for the postcollapse equilibrium structure
of virialized objects which condense out of a low-density cosmological
background universe, either matter-dominated or flat with a cosmological
constant. ... | 376 | academic |
arxiv_abstracts_gfissore | 2,001 | Models for Galactic cosmic-ray propagation
A new numerical model of particle propagation in the Galaxy has been
developed, which allows the study of cosmic-ray and gamma-ray production and
propagation in 2D or 3D, including a full reaction network. This is a further
development of the code which has been used for stud... | 163 | academic |
arxiv_abstracts_gfissore | 2,001 | Comment on the first-order Fermi acceleration at ultra-relativistic
shocks
The first-order Fermi acceleration process at an ultra-relativistic shock
wave is expected to create a particle spectrum with the unique asymptotic
spectral index sigma_gamma >> 1 approximately 2.2. Below, we discuss this
result and difference... | 143 | academic |
arxiv_abstracts_gfissore | 2,001 | On The Cosmic Origins Of Carbon & Nitrogen
We employ analytical and numerical chemical evolution models to study
observed trends in abundance ratios involving carbon, nitrogen, and oxygen.
Several sets of published stellar yields for both intermediate-mass and massive
stars are considered, and the most appropriate set... | 120 | academic |
arxiv_abstracts_gfissore | 2,001 | Observational Tests Of Intermediate Mass Star Yields Using Planetary
Nebulae
This paper summarizes a project designed to study abundances in a sample of
planetary nebulae representing a broad range in progenitor mass and
metallicity. We collect abundances of C, N, and O determined for the entire
sample and compare th... | 161 | academic |
arxiv_abstracts_gfissore | 2,001 | The Curious Adventure of the Ultrahigh Energy Cosmic Rays
These lectures discuss the mysteries involving the production and
extragalactic propagation of ultrahigh energy cosmic rays and suggested
possible solutions. | 40 | academic |
arxiv_abstracts_gfissore | 2,001 | Noise estimation in CMB time-streams and fast map-making. Application to
the BOOMERanG98 data
We describe here an iterative method for jointly estimating the noise power
spectrum from a CMB experiment's time-ordered data, together with the
maximum-likelihood map. We test the robustness of this method on simulated
Boo... | 79 | academic |
arxiv_abstracts_gfissore | 2,001 | Recovering Physical Parameters from Galaxy Spectra Using MOPED
We derive physical parameters of galaxies from their observed spectrum, using
MOPED, the optimized data compression algorithm of Heavens, Jimenez & Lahav
2000. Here we concentrate on parametrising galaxy properties, and apply the
method to the NGC galaxies... | 251 | academic |
arxiv_abstracts_gfissore | 2,001 | New Results from a Survey of Galactic Outflows in Nearby Active Galactic
Nuclei
Recent results from a multiwavelength survey of spatially resolved outflows
in nearby active galaxies are presented. Optical Fabry-Perot and long-slit
spectroscopic data are combined with VLA and ROSAT images, when available, to
probe the... | 161 | academic |
arxiv_abstracts_gfissore | 2,001 | OHS: OH-airglow Suppressor for the Subaru Telescope
This paper describes an OH-airglow Suppressor (OHS) for the infrared Nasmyth
focus of the Subaru telescope. OHS has the capability of eliminating 224
airglow-lines in the J - and H -bands, which are major sources of background
radiation at near-infrared wavelengths u... | 188 | academic |
arxiv_abstracts_gfissore | 2,001 | SHEEP: the ASCA 5-10 keV survey
We present the first results of the hard (5-10 keV) ASCA GIS survey SHEEP
(Search for the High Energy Extragalactic Population).
We have analysed 149 fields covering an area of 39 sq. deg detecting 69
sources. Several of these appear to be associated with QSOs and Seyfert-1
galaxies bu... | 174 | academic |
arxiv_abstracts_gfissore | 2,001 | Local Group Velocity Versus Gravity: Nonlinear Effects
We use numerical simulations to study the relation between the velocity of
the Local Group and its gravitational acceleration. This relation serves as a
test for the kinematic origin of the CMB dipole and as a method for estimating
beta. We calculate the misalignm... | 254 | academic |
arxiv_abstracts_gfissore | 2,001 | BeppoSAX Observations of the Seyfert-2 Galaxies NGC 7172 and ESO 103-G35
We investigate the X-ray spectra of the type-2 Seyfert galaxies NGC 7172 and
ESO 103-G35, using BeppoSAX observations, separated by approximately one year.
We find that the X-ray spectra of both NGC 7172 and ESO 103-G35 can be well
fitted using a... | 252 | academic |
arxiv_abstracts_gfissore | 2,001 | Evolution of globular cluster systems in three galaxies of the Fornax
cluster
We studied and compared the radial profiles of globular clusters and of the
stellar bulge component in three galaxies of the Fornax cluster observed with
the WFPC2 of the HST. A careful comparative analysis of these distributions
confirms t... | 254 | academic |
arxiv_abstracts_gfissore | 2,001 | Galactic nuclear activity induced by globular cluster merging
The interpretation of the difference observed between the radial distribution
of globular clusters and that of halo-bulge stars in elliptical galaxies is
discussed in terms of evolution of their globular cluster systems. I present a
short summary of the evi... | 111 | academic |
arxiv_abstracts_gfissore | 2,001 | Dust Absorption and Emission in Galaxies at High and Low Redshifts
This article reviews three related topics: the extragalactic background l
ight and its sources, evolution models for the dust absorption and emission in
galaxies, and empirical constraints on these transfer pr ocesses in nearby
starburst galaxies. It i... | 86 | academic |
arxiv_abstracts_gfissore | 2,001 | Lepton asymmetry effect on neutrino oscillations and primordial He-4
We analyze the effects of lepton asymmetry on neutrino oscillations and on
cosmological nucleosynthesis with active-sterile oscillating neutrinos. It is
shown that small lepton asymmetries, L < 0.01, whose direct kinetic effect on
nucleosynthesis is ... | 243 | academic |
arxiv_abstracts_gfissore | 2,001 | Global Evolution Models and the Extragalactic Background Light
This article outlines a method to interpret the extragalactic background
light in terms of the large-scale, average properties of galaxies, including
the comoving densities of stars and interstellar gas, metals, and dust. These
quantities are related by a ... | 145 | academic |
arxiv_abstracts_gfissore | 2,001 | Free floating planets in stellar clusters?
We have simulated encounters between planetary systems and single stars in
various clustered environments. This allows us to estimate the fraction of
systems liberated, the velocity distribution of the liberated planets, and the
separation and eccentricity distributions of th... | 186 | academic |
arxiv_abstracts_gfissore | 2,001 | Constraints from the damping tail
The detection of anisotropy in the cosmic microwave background on arcminute
scales by the Cosmic Background Imager (CBI) provides us with our first
measurement of the damping tail and closes one chapter in the CMB story. We now
have experimental verification for all of the features in... | 175 | academic |
arxiv_abstracts_gfissore | 2,001 | Stellar Collisions and Blue Straggler Formation
We review recent 3D hydrodynamic calculations of stellar collisions using the
Smoothed Particle Hydrodynamics (SPH) method, and we discuss the implications
of the results for the formation and evolution of blue stragglers in globular
clusters. We also discuss the constru... | 158 | academic |
arxiv_abstracts_gfissore | 2,001 | Nuclear Reaction Rate Uncertainties and their effects on Nova
Nucleosynthesis Modeling
The nucleosynthesis and other observable consequences of a nova outburst
depend sensitively on the details of the thermonuclear runaway which initiates
the outburst. One important source of uncertainty in our current models is the
... | 104 | academic |
arxiv_abstracts_gfissore | 2,001 | Extensive Air Shower Radio Detection: Recent Results and Outlook
A prototype system for detecting radio pulses associated with extensive
cosmic ray air showers is described. Sensitivity is compared with that in
previous experiments, and lessons are noted for future studies. | 50 | academic |
arxiv_abstracts_gfissore | 2,001 | Microstructure of the Local Interstellar Cloud and the Identification of
the Hyades Cloud
We analyze high-resolution UV spectra of the Mg II h and k lines for 18
members of the Hyades Cluster to study inhomogeneity along these proximate
lines of sight. The observations were taken by the Space Telescope Imaging
Spectr... | 376 | academic |
arxiv_abstracts_gfissore | 2,001 | Thermal Infrared 3--5 m Colors of Obscured and Unobscured Active
Galactic Nuclei
Thermal infrared photometry in the L - and M' -band and L - M' colors of
type-1 and type-2 active galactic nuclei (AGNs) are presented. After combining
our observations with photometric data at similar wavelengths taken from the
literatu... | 330 | academic |
arxiv_abstracts_gfissore | 2,001 | Studying the Galactic Bulge Through Spectroscopy of Microlensed Sources:
II. Observations
The spectroscopy of microlensed sources towards the Galactic bulge provides a
unique opportunity to study (i) the kinematics of the Galactic bulge,
particularly its far-side, (ii) the effects of extinction on the microlensed
sou... | 278 | academic |
arxiv_abstracts_gfissore | 2,001 | Faint X-ray sources resolved in the ASCA Galactic plane survey and their
contribution to the Galactic ridge X-ray emission
The X-ray emission from the central region of the Galactic plane, |l|<45 deg
and |b|<0.4 deg, was studied in the 0.7-10 keV energy band with a spatial
resolution of 3' with the ASCA observatory. ... | 426 | academic |
arxiv_abstracts_gfissore | 2,001 | Mass-Losing Semiregular Variable Stars in Baade's Windows
By cross-correlating the results of two recent large-scale surveys, the
general properties of a well defined sample of semi-regular variable stars have
been determined. ISOGAL mid-infrared photometry and MACHO lightcurves are
assembled for approximately 300 sta... | 384 | academic |
arxiv_abstracts_gfissore | 2,001 | Faint field galaxies: an explanation of the faint blue excess using
number evolution models
Pure luminosity evolution models for galaxies provide an unacceptable fit to
the redshifts and colors of faint galaxies. In this paper we demonstrate, using
HST morphological number counts derived both from the I_814 -band of ... | 339 | academic |
arxiv_abstracts_gfissore | 2,001 | VLBI Observations of a Complete Sample of Radio Galaxies. 10 Years Later
A complete sample of 27 radio galaxies was selected from the B2 and 3CR
catalogs, in order to study their properties on the milliarcsecond scale. In
the Appendix of this paper we present new radio images for 12 of them. Thanks
to the present data... | 235 | academic |
arxiv_abstracts_gfissore | 2,001 | Nebular Emission from Star-Forming Galaxies
We present a new model for computing consistently the line and continuum
emission from galaxies, based on a combination of recent population synthesis
and photoionization codes. We use effective parameters to describe the HII
regions and the diffuse gas ionized by single ste... | 461 | academic |
arxiv_abstracts_gfissore | 2,001 | Special relativistic spherically symmetric Lagrangean hydrodynamics from
General Relativity
We re-derive hydrodynamical equations in General Relativity (GR) in the
comoving reference frame for spherical symmetry and obtain from them the
well-known but not explicitly derived Lagrangean equations in Special
Relativity ... | 192 | academic |
arxiv_abstracts_gfissore | 2,001 | Derivation of preliminary IBIS response matrices with the INTEGRAL
simulator
We have used the IBIS Simulator to produce preliminary response matrices for
the ISGRI and PICsIT detectors in order to help understanding their scientific
performances before the calibration results are available. The derived
matrices, in a... | 99 | academic |
arxiv_abstracts_gfissore | 2,001 | Adaptive Optics Integral Field Spectroscopy of the Young Stellar Objects
in LkH_alpha 225
Progress in understanding the embedded stars in LkHa225 has been hampered by
their variability, making it hard to compare data taken at different times, and
by the limited resolution of the available data, which cannot probe the... | 386 | academic |
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