Skip to content

Astrophysics papers — page 43

astro-phBrowse archive

Accretion Properties of A Sample of Hard X-ray (<60keV) Selected Seyfert 1 Galaxies
We examine the accretion properties in a sample of 42 hard (3-60keV) X-ray selected nearby broad-line AGNs. The energy range in the sample is harder than that usually used in the similar previous…
J. Wang, Y. F. Mao, J. Y. WeiNov 20, 2008
Learn
Analytic Expressions for the Surface Brightness Profile of GRB Afterglow Images
The exact profile of a gamma-ray burst (GRB) afterglow image on the plane of the sky can provide important constraints on the underlying physics. In particular, it can test whether the magnetic field…
Jonathan GranotNov 20, 2008
Learn
Alignment of galaxy spins in the vicinity of voids
We provide limits on the alignment of galaxy orientations with the direction to the void center for galaxies lying near the edges of voids. We locate spherical voids in volume limited samples of…
Anže Slosar, Martin WhiteNov 19, 2008
Learn
No evidence for mass segregation in massive young clusters
Aims. We investigate the validity of the mass segregation indicators commonly used in analysing young stellar clusters. Methods. We simulate observations by constructing synthetic seeing-limited…
J. Ascenso, J. Alves, M. T. V. T. LagoNov 19, 2008
Learn
Combining Semi-analytic Models with Simulations of Galaxy Clusters: the Need for Heating from Active Galactic Nuclei
We present hydrodynamical N-body simulations of clusters of galaxies with feedback taken from semi-analytic models of galaxy formation. The advantage of this technique is that the source of feedback…
C. J. Short, P. A. ThomasNov 19, 2008
Learn
VLBI Observations of SN 2008D
We report on two epochs of very-long-baseline interferometry (VLBI) observations of the Type Ib/c supernova SN 2008D, which was associated with the X-ray outburst XRF 080109. At our first epoch, at t…
M. F. Bietenholz, A. M. Soderberg, N. BartelNov 19, 2008
Learn
Black hole quasinormal mode spectroscopy with LISA
The signal-to-noise ratio (SNR) for black hole quasinormal mode sources of low-frequency gravitational waves is estimated using a Monte Carlo approach that replaces the all-sky average approximation.…
Manish M. Jadhav, Lior M. BurkoNov 19, 2008
Learn
Mean-field dynamos in random Arnold-Beltrami-Childress and Roberts flows
We study magnetic field evolution in flows with fluctuating in time governing parameters in electrically conducting fluid. We use a standard mean-field approach to derive equations for large-scale…
N. Kleeorin, I. Rogachevskii, D. Sokoloff et al.Nov 19, 2008
Learn
Quantifying the fast outflow in the luminous Seyfert galaxy PG1211+143
We report two new XMM-Newton observations of PG1211+143 in December 2007, again finding evidence of the fast outflow of highly ionised gas first detected in 2001. Stacking the new spectra with those…
K. A. Pounds, J. N. ReevesNov 19, 2008
Learn
An extensive photometric study of the Blazhko RR Lyrae star MW Lyr: II. Changes in the physical parameters
The analysis of the multicolour photometric observations of MW Lyr, a large modulation amplitude Blazhko variable, shows for the first time how the mean global physical parameters vary during the…
J. Jurcsik, Á. Sódor, B. Szeidl et al.Nov 19, 2008
Learn
Expected high energy emission from GRB 080319B and origins of the GeV emission of GRBs 080514B, 080916C and 081024B
We calculate the high energy (sub-GeV to TeV) prompt and afterglow emission of GRB 080319B that was distinguished by a naked-eye optical flash and by an unusual strong early X-ray afterglow. There…
Yuan-Chuan Zou, Yi-Zhong Fan, Tsvi PiranNov 19, 2008
Learn
New SETI Sky Surveys for Radio Pulses
Berkeley conducts 7 SETI programs at IR, visible and radio wavelengths. Here we review two of the newest efforts, Astropulse and Fly's Eye. A variety of possible sources of microsecond to…
Andrew Siemion, Joshua Von Korff, Peter McMahon et al.Nov 19, 2008
Learn
The [O II] lambda 3727 Luminosity Function at z ~ 1
We measure the evolution of the [OII]lambda 3727 luminosity function at 0.75<z<1.45 using high-resolution spectroscopy of ~14,000 galaxies observed by the DEEP2 galaxy redshift survey. We find that…
Guangtun Zhu, John Moustakas, Michael R. BlantonNov 19, 2008
Learn
On the gravitational content of molecular clouds and their cores
(Abridged) The gravitational term for clouds and cores entering in the virial theorem is usually assumed to be equal to the gravitational energy, since the contribution to the gravitational force…
Javier Ballesteros-Paredes, Gilberto C. Gómez, Bárbara Pichardo et al.Nov 19, 2008
Learn
Diffuse Extragalactic Background Radiation
Attenuation of high--energy gamma rays by pair--production with UV, optical and IR background photons provides a link between the history of galaxy formation and high--energy astrophysics. We present…
Joel R. Primack, Rudy C. Gilmore, Rachel S. SomervilleNov 19, 2008
Learn
Comprehensive Observations of a Solar Minimum CME with STEREO
We perform the first kinematic analysis of a CME observed by both imaging and in situ instruments on board STEREO, namely the SECCHI, PLASTIC, and IMPACT experiments. Launched on 2008 February 4, the…
B. E. Wood, R. A. Howard, S. P. Plunkett et al.Nov 19, 2008
Learn
Wide Area X-ray Surveys for AGN and Starburst Galaxies
While often the point sources in X-ray surveys are dominated by AGN, with the high sensitivity of modern X-ray telescopes such as Chandra and XMM-Newton normal/starburst galaxies are also being…
A. PtakNov 19, 2008
Learn
The chromospherically active binary star EI Eridani II. Long-term Doppler imaging
Data from 11 years of continuous spectroscopic observations of the active RS CVn-type binary star EI Eridani - gained at NSO/McMath-Pierce, KPNO/Coude Feed and during the MUSICOS 98 campaign - were…
A. Washuettl, K. G. Strassmeier, M. WeberNov 19, 2008
Learn
Impact of sub-solar metallicities on photometric redshifts
With the advent of deep photometric surveys the use of photometric redshifts, obtained with a variety of techniques, has become more and more widespread. Giving access to galaxies with a wide range…
Ralf Kotulla, Uta FritzeNov 19, 2008
Learn
Angular momentum and clustering properties of early dark matter halos
In this paper we study the angular momentum properties of simulated dark matter halos at high redshift that likely host the first stars in the Universe. Calculating the spin distributions of these…
Andrew J. Davis, Priyamvada NatarajanNov 19, 2008
Learn
Photometric redshifts for the CFHTLS-Wide
We want to derive bias free, accurate photometric redshifts for those fields of the CFHTLS-Wide data which are covered in the u*, g', r', i' and z' filters and are public on January 2008. These are…
Fabrice Brimioulle, Michael Lerchster, Stella Seitz et al.Nov 19, 2008
Learn
Hαspectropolarimetry of RY Tau and PX Vul
Aims: To detect line effects using spectropolarimetry in order to find evidence of rotating disks and their respective symmetry axes in T Tauri stars. Methods: We used the IAGPOL imaging polarimeter…
A. Pereyra, A. M. Magalhães, F. X. de AraújoNov 19, 2008
Learn
Star Formation from Spitzer (Lyman) to Spitzer (Space Telescope) and Beyond
A summary of JENAM 2008 Symposium 9 "Star Formation from Spitzer (Lyman) to Spitzer (Space Telescope) and Beyond", held in Vienna, 10-12 September 2008.
Joao Alves, Virginia TrimbleNov 19, 2008
Learn
The location and kinematics of the coronal-line emitting regions in AGN
We use the photoionisation code Cloudy to determine both the location and the kinematics of the optical forbidden, high ionisation line (hereafter, FHIL) emitting gas in the narrow line Seyfert 1…
J. R. Mullaney, M. J. Ward, C. Done et al.Nov 19, 2008
Learn
Kinematic properties of early-type galaxy haloes using planetary nebulae
We present new planetary nebulae (PNe) positions, radial velocities, and magnitudes for 6 early-type galaxies obtained with the Planetary Nebulae Spectrograph, their two-dimensional velocity and…
L. Coccato, O. Gerhard, M. Arnaboldi et al.Nov 19, 2008
Learn
← PreviousPage 43Next →