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Possible discovery of threeγ-ray pulsars
Yu, K. N.; Young, E. C. M.; Lu, Tan +1 more
The possible discovery of threeγ-ray pulsars 0656 + 14, 0950 + 08, and 1822 - 09 based on COS-B data analysis is reported. Their light curves, the other related features, and the methods leading to these results are also given. Among these three pulsars, PSR 0656 + 14 is the most significant one for being aγ-ray pulsar.
The spectral variability of the gamma-ray emission from Geminga and VELA and its implications.
Grenier, I. A.; Hermsen, W.; Henriksen, R. N.
The gamma-ray emissions from Geminga and from the Interpeak 1 component of the Vela pulsar were analyzed in order to compare their spectral properties between 50 MeV and 5 GeV and to study their variability between 1975 and 1982 using the COS-B data. The stability of both sources above about 200 and 300 MeV, respectively, retaining an E exp -2.0 +…
The COS-B X-ray observations of X-ray binaries.
van der Klis, M.
The observational information on X-ray binaries that was collected with the 80 sq cm auxiliary X-ray detector onboard the COS-B gamma-ray satellite is reviewed. The results illustrate that in the study of X-ray binaries observations of long duration are extremely effective, even when using a small instrument.
Pulsar studies with GRO-COMPTEL
Strong, A. W.; Schönfelder, V.; Kuiper, L. +9 more
Pulsar measurements performed by the experiment COMPTEL, aboard the Compton Gamma Ray Observatory, are described. The main results refer to the Crab and Vela pulsars whose pulse shape characteristics are given in some detail and light curves are compared with those above 50 MeV, as observed by the COS-B satellite. No other gamma-ray pulsars have b…
Are PSR 0656+14, PSR 0950+08, and PSR 1822-09 gamma-ray pulsars?
Brown, Lawrence E.; Hartmann, Dieter H.
The possible discovery of three new γ-ray pulsars PSR 0656+14, PSR 0950+08, and PSR 1822-09 (Ma, Lu, Yu, and Young, 1993) in data obtained with the COS-B experiment is reinvestigated using a refined technique for pulsar light curve analysis. The results of this study do not confirm the previously claimed γ-ray pulsar nature of any of these pulsars…
Precise measurement of the right ascension of the Geminga pulsar using COS-B data.
Li, T. P.; Cheng, L. X.; Ma, Y. Q. +2 more
We have obtained a more precise value of the right ascension and a new spin evolution law of the Geminga pulsar using COS-B data on the assumption 0r high stability of the absolute phase. The new value is a(1950)=6h30m59s .057, with error about 0.5 arcsec, compared with the 3.2 arcsecs from the Einstein HRI result.…
Analysis of COS-B and HEAO-B satellite data of the pulsar Geminga
Wu, Mei; Ma, Lin; Ma, Yu-qian +4 more
We have made timing and spectral analyses of COS-B and HEAO-B satellite data of the pulsar Geminga and our results further confirm that Geminga is a pulsar with a strong γ emission and a weak X emission.
Search for short bursts of gamma-ray emission in spark chamber data: application to COS-B
Buccheri, R.; Maccarone, M. C.; Fry, W. F.
We describe an analysis method aimed to the detection of short (<1000 s) bursts in the emission of gamma-ray sources using spark chamber data. The method utilizes a maximum likelihood technique which looks for accumulations of photons, compatible with the point spread function of the experiment, within the whole observing time and the field-of-…
Analysis of COS-B and HEAO-B satellite data of the pulsar Geminga
Song, Li-Ming; Wu, Mei; Ma, Yu-Qian +4 more
Timing and spectral analysis of COS-B and HEAO-B satellite data of the pulsar Geminga are presented. The results confirm that Geminga is a pulsar with a strong gamma emission and a weak X-ray emission. A phase histogram of Geminga in different energy ranges from a summation of four COS-B observations is given.
How robust are the EGRET AGN gamma-ray identifications?
Bignami, G. F.; Caraveo, P.; Ciliegi, P.
Several AGNs have been proposed as identifications of gamma-ray sources discovered by CGRO. Using the NED database, the authors show that these AGNs are not the only extragalactic objects within the error boxes of the sources. Therefore, an in-depth study is needed on a case-by-case basis to access the most probable counterparts of the gamma-ray s…