中文
相关论文

相关论文: 3EG J2016+3657: Confirming an EGRET Blazar Behind …

200 篇论文

We present a high-energy study of the intriguing COS-B gamma-ray field, 2CG 075+00, in order to search for possible counterparts. New EGRET data show that the COS-B emission probably corresponds to two localized gamma-ray sources, 3EG…

天体物理学 · 物理学 2009-10-31 R. Mukherjee , E. V. Gotthelf , J. Halpern , M. Tavani

Statistical studies indicate that the 271 point sources of high-energy gamma rays belong to two groups: a Galactic population and an isotropic extragalactic population. Many unidentified extragalactic sources are certainly blazars, and it…

天体物理学 · 物理学 2009-11-10 P. M. Wallace , S. D. Bloom , M. S. Lewis

B2013+370 and B2023+336 are two blazars at low-galactic latitude that were previously proposed to be the counterparts for the EGRET unidentified sources, 3EG J2016+3657 and 3EG J2027+3429. Gamma-ray emission associated with the EGRET…

高能天体物理现象 · 物理学 2015-06-03 E. Kara , M. Errando , W. Max-Moerbeck , E. Aliu , M. Bottcher , P. Fortin , J. P. Halpern , R. Mukherjee , A. C. S. Readhead , J. L. Richards

The EGRET source 3EG J1835+5918 is the brightest and most accurately positioned of the as-yet unidentified high-energy gamma-ray sources at high Galactic latitude (l,b=89,25). We present a multiwavelength study of the region around it,…

天体物理学 · 物理学 2009-10-31 N. Mirabal , J. P. Halpern , M. Eracleous , R. H. Becker

Using survey data, we have re-evaluated the correlation of flat spectrum radio sources with EGRET sources in the Northern sky. A likelihood analysis incorporating the radio and X-ray properties and the Gamma-ray source localization is used…

天体物理学 · 物理学 2009-11-07 David Sowards-Emmerd , Roger W. Romani , Peter F. Michelson

We present a method to assess the reliability of the identification of EGRET sources with extragalactic radio sources. We verify that EGRET is detecting the blazar class of AGN. However, many published identifications are found to be…

天体物理学 · 物理学 2009-10-28 J. R. Mattox , J. Schachter , L. Molnar , R. C. Hartman , A. R. Patnaik

The identity of the persistent EGRET sources in the Galactic plane is largely a mystery. For one of these, 3EG J2227+6122, our complete census of X-ray and radio sources in its error circle reveals a remarkable superposition of an…

天体物理学 · 物理学 2009-10-31 J. P. Halpern , E. V. Gotthelf , K. M. Leighly , D. J. Helfand

We have conducted a multiwavelength study of several radio sources within or near the error boxes of EGRET unidentified sources at mid to high Galactic latitude, under the hypothesis that the radio sources are blazars and are thus the best…

天体物理学 · 物理学 2009-10-30 S. D. Bloom , R. C. Hartman , H. Terasranta , M. Tornikoski , E. Valtaoja

The Third EGRET Catalog (3EG) lists 66 high-confidence identifications of sources with Active Galactic Nuclei (AGN). All are classified as belonging to the blazar class, with the only exception of the nearby radio galaxy Centaurus A. We…

天体物理学 · 物理学 2009-11-10 V. Sguera , L. Bassani , A. Malizia , A. J. Dean , R. Landi , J. B. Stephen

The broad-line radio galaxy 3C111 has been suggested as the counterpart of the gamma-ray source 3EGJ0416+3650. While 3C111 meets most of the criteria for a high-probability identification, like a bright flat-spectrum radio core and a…

天体物理学 · 物理学 2009-11-13 R. C. Hartman , M. Kadler , J. Tueller

We report on the association of an X-ray source (WGA J2025.1+3342), serendipitously found with BeppoSAX in two separate observations, with the unidentified EGRET source 3EG J2027+3429. The source is detected from 1 keV up to about 100 keV,…

天体物理学 · 物理学 2009-11-10 V. Sguera , A. Malizia , L. Bassani , J. B. Stephen , G. Di Cocco

3EG J1835+5918 is the brightest of the so-called unidentified EGRET sources at intermediate galactic latitude (l,b)=(89,25). We obtained complete radio, optical, and X-ray coverage of its error box, discovering a faint ultrasoft X-ray…

天体物理学 · 物理学 2007-05-23 N. Mirabal , J. Halpern , R. Mukherjee , E. Gotthelf , F. Camilo

We discuss the nature of the unidentified EGRET source 3EG J1621+8203. In an effort to identify the gamma-ray source, we have examined X-ray images of the field from ROSAT PSPC, ROSAT HRI, and ASCA GIS. Of the several faint X-ray point…

天体物理学 · 物理学 2009-11-07 R. Mukherjee , J. Halpern , N. Mirabal , E. V. Gotthelf

We present a multiwavelength analysis of the high-energy gamma-ray source 3EG J2006-2321. The flux of this source above 100 MeV is shown to be variable on time scales of days and months. Optical observations and careful examination of…

天体物理学 · 物理学 2009-11-07 P. M. Wallace , J. P. Halpern , A. M. Magalhaes , D. J. Thompson

The unidentified EGRET source 3EG J1828+0142, located at (l,b) ~ (31.9,5.8) (Hartman et al. 1999), is particularly enigmatic since it displays very high variability over timescales of months (Torres et al. 2000, Tompkins 1999) yet no blazar…

The low dispersion (400$\AA$/mm) spectrum of the optical counterpart of a flat-spectrum radio source 87GB 080315.5+512613, which is one of two possible radio counterparts of 2EG J0809+5117, was obtained recently. The optical counterpart,…

天体物理学 · 物理学 2009-09-25 Xue-Bing Wu , Qi-Bin Li , Yong-Heng Zhao , Li Cao

We present a catalog of point gamma-ray sources detected by the EGRET detector aboard the Compton Gamma Ray Observatory. We have used the whole gamma-ray dataset of reprocessed photons at energies above 100 MeV together with new Galactic…

天体物理学 · 物理学 2009-11-13 Jean-Marc Casandjian , Isabelle A. Grenier

The 3rd EGRET Catalog of High-energy Gamma-ray Sources contains 170 unidentified sources, and there is great interest in the nature of these sources. One means of determining source class is the study of flux variability on time scales of…

天体物理学 · 物理学 2009-10-31 P. M. Wallace , D. L. Bertsch , S. D. Bloom , N. J. Griffis , R. C. Hartman , D. A. Kniffen , D. J. Thompson

The limited angular resolution of gamma-ray telescopes prevents the straight identification of the majority of the sources detected so far. This is particularly true for the low latitude, probably galactic ones, only 10 % of which has been…

天体物理学 · 物理学 2007-05-23 N. La Palombara , G. F. Bignami , P. Caraveo , A. De Luca , S. Mereghetti , R. Mignani , E. Hatziminaoglou

Published EGRET spectra from blazars extend only to 10 GeV, yet EGRET has detected approximately 2000 gamma-rays above 10 GeV of which about half are at high Galactic latitude. We report a search of these high-energy gamma-rays for…

天体物理学 · 物理学 2009-11-06 Brenda L. Dingus , David L. Bertsch
‹ 上一页 1 2 3 10 下一页 ›