中文
相关论文

相关论文: Unifying B2 radio galaxies with BL Lac objects

200 篇论文

From ROSAT imaging data we have detections and upper limits for a sample of 26 tailed radio sources in clusters of galaxies mostly from the sample of O'Dea \& Owen (1985). All sixteen of the detected sources are unresolved in the ROSAT PSPC…

天体物理学 · 物理学 2007-05-23 A. C. Edge H. Roettgering

Multifiber optical spectroscopy has been performed on galaxies in the vicinity of strong, nearby radio galaxies. These radio galaxies were selected from the 3CR and B2 catalogs based on their exclusion from the Abell catalog, which is…

天体物理学 · 物理学 2009-11-07 Neal A. Miller , Michael J. Ledlow , Frazer N. Owen , John M. Hill

In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 {\it Fermi} Large Area Telescope (LAT) detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy…

高能天体物理现象 · 物理学 2022-06-15 Yasushi Fukazawa , Hiroto Matake , Taishu Kayanoki , Yoshiyuki Inoue , Justin Finke

Nearly 50% of all sources detected by the Fermi Large Area Telescope are classified as blazars or blazar candidates, one of the most elusive classes of active galaxies. Additional blazars can also be hidden within the sample of unidentified…

高能天体物理现象 · 物理学 2020-07-13 E. J. Marchesini , A. Paggi , F. Massaro , N. Masetti , R. D'Abrusco , I. Andruchow

We present a morphological and spectral study of a sample of 99 BL Lacs using the LOFAR Two-Metre Sky Survey Second Data Release (LDR2). Extended emission has been identified at gigahertz frequencies around BL Lacs, but with LDR2 it is now…

BL Lac objects are an elusive and rare class of active galactic nuclei. For years their evolutionary behavior has appeared inconsistent with the trend observed in the population of AGN at large. The so-called ``negative'' evolution implies…

天体物理学 · 物理学 2017-08-23 Anna Wolter , Francesca Cavallotti , John T. Stocke , Travis Rector

Hard X-ray properties of beamed AGN have been published in the 105-month Swift/BAT catalog, but there have not been any studies carried out so far on a well-defined, radio-selected sample of low-peaked blazars in the hard X-ray band. Using…

This paper presents a detailed analysis of the radio properties for the sample of faint radio sources introduced in Magliocchetti et al. (2000). The sample comprises mainly intrinsically low-power sources whose majority ($\simgt 70$ per…

天体物理学 · 物理学 2009-11-07 M. Magliocchetti , A. Celotti , L. Danese

We present a catalog of cross-correlated radio, infrared and X-ray sources using a very restrictive selection criteria with an IDL-based code developed by us. The significance of the observed coincidences was evaluated through Monte Carlo…

The parsec-scale radio properties of 232 active galactic nuclei (AGNs), most of which are blazars, detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed contemporaneously by the Very Long…

高能天体物理现象 · 物理学 2015-06-11 J. D. Linford , G. B. Taylor , F. K. Schinzel

The most elusive and extreme sub-class of active galactic nuclei (AGNs), known as BL Lac objects, shows features that can only be explained as the result of relativistic effects occurring in jets pointing at a small angle with respect to…

星系天体物理 · 物理学 2020-09-09 F. Massaro , A. Capetti , A. Paggi , R. D. Baldi , A. Tramacere , I. Pillitteri , R. Campana

BL Lac objects are active nuclei, hosted in massive elliptical galaxies, the emission of which is dominated by a relativistic jet closely aligned with the line of sight. This implies the existence of a parent population of sources with a…

高能天体物理现象 · 物理学 2016-11-26 Renato Falomo , Elena Pian , Aldo Treves

We investigate the nature of the BL Lac candidates in the northern part of the 2BL sample (\cite{Londish02}) searching for optical variability by means of $R_C$ band photometry with the Asiago 1.8 and Loiano 1.5 meter telescopes during…

天体物理学 · 物理学 2009-11-10 R. Nesci , S. Sclavi , E. Massaro

We investigate the properties of the host galaxies of X-ray selected (high frequency peaked) BL Lac objects using a large and homogeneous data set of high spatial resolution R-band observations of 52 BL Lacs in the EMSS and Slew samples.…

天体物理学 · 物理学 2007-05-23 R. Falomo , J. K. Kotilainen

We present soft X-ray spectra of 74 BL Lacertae objects observed with the PSPC detector on board of the ROSAT satellite. The sample contains all BL Lac objects detected during the pointed observation phase as a target or serendipitously. We…

天体物理学 · 物理学 2007-05-23 G. Lamer , H. Brunner , R. Staubert

We review the main results from several radio, X-ray and multi-frequency surveys on the topic of cosmological evolution of BL Lacertae objects. Updated findings on BL Lac evolution following the recent identification of many sources in the…

天体物理学 · 物理学 2007-05-23 P. Giommi , A. Pellizzoni , M. Perri , P. Padovani

X-ray studies of normal late-type galaxies have shown that non-nuclear X-ray emission is typically dominated by X-ray binaries, and provides a useful measure of star formation activity. We have modeled the X-ray evolution of late-type…

高能天体物理现象 · 物理学 2015-05-27 Zhao-Yu Zuo , Xiang-Dong Li

We present the results of near-infrared H band (1.65 microns) imaging of 11 BL Lac objects with redshifts ranging from z = 0.05 to 0.9. We are able to clearly detect the host galaxy in seven low redshift (z<=0.24) BL Lacs, while the four…

天体物理学 · 物理学 2007-05-23 J. K. Kotilainen , R. Falomo , R. Scarpa

We review recent results on populations of compact X-ray sources in normal galaxies. The luminosity distributions of low and high mass X-ray binaries in nearby galaxies appear to be described by the respective ``universal'' luminosity…

天体物理学 · 物理学 2008-11-26 M. Gilfanov

We present and discuss the X-ray luminosity function (XLF) of the ROSAT Brightest Cluster sample (BCS), an X-ray flux limited sample of clusters of galaxies in the northern hemisphere compiled from ROSAT All-Sky Survey data. The BCS allows…

天体物理学 · 物理学 2009-10-30 H. Ebeling , A. C. Edge , A. C. Fabian , S. W. Allen , C. S. Crawford , H. Boehringer