相关论文: Multiwavelength Searches of Unidentified EGRET Sou…
In the error box of 3EG J1835+5918, the brightest as-yet unidentified EGRET source at intermediate Galactic latitude, we find a weak, ultrasoft X-ray source at energies E < 0.3 keV in the ROSAT All-Sky Survey. Deep optical imaging at the…
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,…
We report a deep optical imaging observation by the Subaru telescope for a very soft X-ray source RX J1836.2+5925, which has been suspected to be an isolated neutron star associated with the brightest as-yet unidentified EGRET source…
The EGRET telescope has repeatedly observed 3EG J1835+5918 as a bright and steady source of high-energy gamma-ray radiation which has not yet been indentified. EGRET data from CGRO observation cycle 1 to 7 have been reanalysed above 100 MeV…
We describe Chandra, HST, and radio observations that reveal a radio-quiet but magnetospherically active neutron star in the error circle of the high-energy gamma-ray source 3EG J1835+5918, the brightest of the unidentified EGRET sources at…
The EGRET telescope aboard NASAs Compton GRO has repeatedly detected 3EG J1835+5918, a bright and steady source of high-energy gamma-ray emission with no identification suggested until recently. The long absence of any likely counterpart…
We report unsuccessful searches for pulsations from the neutron star RX J1836.2+5925 identified with the EGRET source 3EG J1835+5918. A 24 hr observation with the NRAO Green Bank Telescope at 820 MHz placed an upper limit on flux density of…
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…
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…
In search of the counterpart to the brightest unidentified gamma-ray source 3EG J2020+4017 we report on new X-ray and radio observations of the gamma-Cygni field with the Chandra X-ray Observatory and with the Green Bank Telescope. We also…
As part of an effort to associate the unidentified EGRET gamma-ray sources with pulsars, error boxes for 19 sources were searched using Arecibo at 327-MHz. The sources were chosen to be out-of-plane and possibly associated with the Gould…
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…
We recently identified the blazar-like radio source G74.87+1.22 (B2013+370) as the counterpart of the high-energy gamma-ray source 3EG J2016+3657 in the Galactic plane. However, since most blazar identifications of EGRET sources are only…
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…
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 primary objective of the study of unidentified EGRET sources with INTEGRAL is to locate with a few arcminute accuracy the hard X-ray / soft gamma-ray counterparts within the EGRET error circle or to determine upper limits on their…
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…
We have conducted a radio pulsar survey of 56 unidentified gamma-ray sources from the 3rd EGRET catalog which are at intermediate Galactic latitudes (5 deg. < |b| < 73 deg.). For each source, four interleaved 35-minute pointings were made…
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…
Microquasars are promising candidates to emit high-energy gamma-rays. Moreover, statistical studies show that variable EGRET sources at low galactic latitudes could be associated with the inner spiral arms. The variable nature and the…