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High-mass X-ray binaries in the Small Magellanic Cloud: the luminosity function
Gilfanov, M.; Shtykovskiy, P.
We study a population of compact X-ray sources in the Small Magellanic Cloud (SMC) using archival data from the XMM-Newton observatory. The total area of the survey is ~1.5 deg2 with the limiting sensitivity of ~10-14 erg s-1 cm-2, corresponding to a luminosity of ~4.3 × 1033 erg s-1
Hard Spectra of X-ray Pulsars from INTEGRAL Data
Sunyaev, R. A.; Tsygankov, S. S.; Lutovinov, A. A. +1 more
We present spectra for 34 accretion-powers X-ray pulsars and one millisecond pulsar that were within the field of view of the INTEGRAL observatory over two years (December 2002 January 2005) of its in-orbit operation and that were detected by its instruments at a statistically significant level (> 8σ in the energy range 18 60 keV). There are se…
Hubble Space Telescope ultraviolet spectroscopy of blazars: emission-line properties and black hole masses
Pian, E.; Falomo, R.; Treves, A.
The ultraviolet (UV) spectra of 16 blazars (<z>~= 1) from the archives of the Hubble Space Telescope Faint Object Spectrograph have been analysed in order to study in a systematic way the properties of their broad UV emission lines. We find that the luminosities of the most prominent and intense lines, Lyα and CIVλ1549, are similar to those …
Evolution of Field Early-Type Galaxies: The View from GOODS CDFS
Lisker, Thorsten; Mobasher, Bahram; Ferreras, Ignacio +2 more
We explore the evolution of field early-type galaxies in a sample extracted from the ACS images of the southern GOODS field. The galaxies are selected by means of a nonparametric analysis, followed by visual inspection of the candidates with a concentrated surface brightness distribution. We furthermore exclude from the final sample those galaxies…
On the generation of solitary waves observed by Cluster in the near-Earth magnetosheath
Gurnett, D. A.; Balogh, A.; Lakhina, G. S. +13 more
Through case studies involving Cluster waveform observations, solitary waves in the form of bipolar and tripolar pulses have recently been found to be quite abundant in the near-Earth dayside magnetosheath. We expand on the results of those previous studies by examining the distribution of solitary waves from the bow shock to the magnetopause usin…
On the transmission-dominated to reprocessing-dominated spectral state transitions in Seyfert 2 galaxies
Fiore, F.; Guainazzi, M.; Iwasawa, K. +2 more
We present Chandra and XMM-Newton observations of a small sample (11 objects) of optically selected Seyfert 2 galaxies, for which ASCA and BeppoSAX had suggested Compton-thick obscuration of the active galactic nucleus (AGN). The main goal of this study is to estimate the rate of transitions between `transmission-dominated' and `reprocessing-domin…
On the Limb Darkening, Spectral Energy Distribution, and Temperature Structure of Procyon
Ludwig, H. -G.; Kervella, P.; Aufdenberg, J. P.
We have fit synthetic visibilities from three-dimensional (CO5BOLD+PHOENIX) and one-dimensional (PHOENIX, ATLAS 12) model stellar atmospheres of Procyon (F5 IV) to high-precision interferometric data from the VLT Interferometer (K band) and from the Mark III interferometer (500 and 800 nm). These data sets provide a test of theoretical …
Intrinsic Curvature in the X-Ray Spectra of BL Lacertae Objects
Perlman, Eric S.; Georganopoulos, Markos; Stocke, John T. +10 more
We report results from XMM-Newton observations of 13 X-ray bright BL Lacertae objects, selected from the Einstein Slew Survey sample (SSS). The survey was designed to look for evidence of departures of the X-ray spectra from a simple power-law shape (i.e., curvature and/or line features) and to find objects worthy of deeper study. Our data are gen…
A 5-Micron-Bright Spot on Titan: Evidence for Surface Diversity
Drossart, Pierre; Sotin, Christophe; Sicardy, Bruno +32 more
Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80°W and 20°S. This area is bright in reflected light at all observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Sci…
Quasi thermal noise spectroscopy in the inner magnetosphere of Saturn with Cassini/RPWS: Electron temperatures and density
Moncuquet, Michel; Meyer-Vernet, Nicole; Lecacheux, Alain +2 more
On 1 July 2004, the Cassini spacecraft performed its Saturn orbit insertion, twice crossing the equatorial plane between the G and F rings. The radio HF receiver observed a peak at the upper-hybrid frequency and weakly banded emissions having well-defined minima at gyroharmonics. We show that through most of the encounter, these emissions do not r…