ﻻ يوجد ملخص باللغة العربية
We have studied the SED of the quasar LBQS 0102-2713. The available multiwavelength data are one optical spectrum between 3200 and 7400 A, 7 HST FOS spectra between 1700 and 2300 A, one GALEX NUV flux density and a K_S magnitude obtained from NED, and 3 public ROSAT PSPC pointed observations in the 0.1$-$2.4 keV energy band. The alpha_ox values obtained are -2.3 and -2.2, respectively, comparable to BAL quasars. The ROSAT photon index is 6.0+-1.3. The 2500 A luminosity density is about a factor of 10 higher compared to the mean of the most luminous SDSS quasars. We argue that the object might be indicative for a new class of quasars with an unusual combination in their UV-, X-ray, and N_H properties.
We have analyzed the first XMM-Newton, Swift and archival ROSAT PSPC observations of the quasar LBQS 0102-2713.The object was selected from the ROSAT archive as being notable due to the steep soft X-ray photon index and due to the UV brightness based
Spectral energy distributions (SEDs) of the central few tens of parsec region of some of the nearest, most well studied, active galactic nuclei (AGN) are presented. These genuine AGN-core SEDs, mostly from Seyfert galaxies, are characterised by two m
During galaxy-galaxy interactions, massive gas clouds can be injected into the intergalactic medium which in turn become gravitationally bound, collapse and form stars, star clusters or even dwarf galaxies. The objects resulting from this process are
(Abridged) We attempt to infer the accretion mechanism and radiative processes giving rise to the SEDs of a well-defined optically-selected sample of LINERs showing a definite detection of broad Halpha emission (LINER 1s). We construct SEDs for six L
(Abridged) We have conducted a detailed investigation of the broad-band spectral properties of the gamma-ray selected blazars of the Fermi LAT Bright AGN Sample (LBAS). By combining our accurately estimated Fermi gamma-ray spectra with Swift, radio,