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Full-Text Articles in Physical Sciences and Mathematics
Comptel Imaging Of The Galactic Disk And The Separation Of Diffuse Emission And Point Sources, H Bloemen, W Hermsen, B Swanenburg, C De Vries, R Diehl, V. Schonfelder, H Steinle, A W. Strong, A Connors, Mark L. Mcconnell, D Morris, G Stacy, K Bennett, C Winkler
Comptel Imaging Of The Galactic Disk And The Separation Of Diffuse Emission And Point Sources, H Bloemen, W Hermsen, B Swanenburg, C De Vries, R Diehl, V. Schonfelder, H Steinle, A W. Strong, A Connors, Mark L. Mcconnell, D Morris, G Stacy, K Bennett, C Winkler
Physics & Astronomy
The first MeV image of the inner Galaxy obtained with the COMPTEL telescope aboard the Compton Gamma-Ray Observatory shows a structured ridge of emisssion along the Galactic equator which probably consists of diffuse radiation and unresolved discrete sources. The intensity distribution of this ridge distinctly differs from the expected distribution for a simple model of the diffuse radiation. Most remarkable are the observed excursions out of the disk, which may hint at the presence of gamma-ray point sources located several degrees away from the mid-plane, but a diffuse origin cannot be excluded. If these are indeed discrete sources, a substantial …
Observations Of Cygnus X-1 Comptel During 1991, Mark L. Mcconnell, D J. Forrest, James M. Ryan, W Collmar, V. Schonfelder, H Steinle, A W. Strong, R Van Dijk, W Hermsen, K Bennett
Observations Of Cygnus X-1 Comptel During 1991, Mark L. Mcconnell, D J. Forrest, James M. Ryan, W Collmar, V. Schonfelder, H Steinle, A W. Strong, R Van Dijk, W Hermsen, K Bennett
Physics & Astronomy
The Compton Telescope (COMPTEL) experiment on the Compton Gamma-Ray Observatory (CGRO) has observed the Cygnus region on two occasions during the first (sky survey) phase of its mission. These data represent the most sensitive observations to date of Cygnus X-1 in the 0.75-30 MeV range. The observations in 1991 June and August both showed evidence for emission in the 0.75-2 MeV energy range. The flux level was larger by about a factor of 2 during the August observation. The spectral data were analyzed in the context of a Wien spectral model (the high-energy limit of the Sunyaev-Titarchuk Comptonization spectrum). Fits …
Comptel Measurements Of The Gamma-Ray Burst Grb 930131, James M. Ryan, K Bennett, W Collmar, A Connors, Gerald J. Fishman, J Greiner, L O. Hanlon, W Hermsen, R M. Kippen, C Kouveliotou, L Kuiper, G G. Lichti, John R. Macri, J. Mattox, Mark L. Mcconnell, B Mcnamara, C Meegan, V. Schonfelder, R Vandijk, M Varendorff, W Webber, C Winkler
Comptel Measurements Of The Gamma-Ray Burst Grb 930131, James M. Ryan, K Bennett, W Collmar, A Connors, Gerald J. Fishman, J Greiner, L O. Hanlon, W Hermsen, R M. Kippen, C Kouveliotou, L Kuiper, G G. Lichti, John R. Macri, J. Mattox, Mark L. Mcconnell, B Mcnamara, C Meegan, V. Schonfelder, R Vandijk, M Varendorff, W Webber, C Winkler
Physics & Astronomy
On 1993 January 31 at 1857:12 Universal Time (UT), the Imaging Compton Telescope COMPTEL onboard the Compton Gamma Ray Observatory (CGRO) detected the cosmic gamma-ray burst GRB 930131. COMPTEL's MeV imaging capability was employed to locate the source to better than 2 deg (1 sigma error radius) within 7 hr of the event, initiating a world-wide search for an optical and radio counterpart. The maximum likelihood position of the burst from the COMPTEL data is alpha2000 = 12h 18m, delta2000 = -9 deg 42 min, consistent with independent CGRO-Burst and Transient Source Experiment (CGRO-BATSE) and Energetic Gamma Ray …
Instrument Description And Performance Of The Imaging Gamma-Ray Telescope Comptel Aboard The Compton Gamma-Ray Observatory, V. Schonfelder, H. Aarts, K Bennett, H Deboer, J. Clear, W Collmar, A Connors, A. Deerenberg, R Diehl, A. Von Dordrecht, J W. Den Herder, W Hermsen, R M. Kippen, L Kuiper, G G. Lichti, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, G. Simpson, M. Snelling, G Stacy, H Steinle, A W. Strong, B Swanenburg, B G. Taylor, C De Vries, C Winkler
Instrument Description And Performance Of The Imaging Gamma-Ray Telescope Comptel Aboard The Compton Gamma-Ray Observatory, V. Schonfelder, H. Aarts, K Bennett, H Deboer, J. Clear, W Collmar, A Connors, A. Deerenberg, R Diehl, A. Von Dordrecht, J W. Den Herder, W Hermsen, R M. Kippen, L Kuiper, G G. Lichti, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, G. Simpson, M. Snelling, G Stacy, H Steinle, A W. Strong, B Swanenburg, B G. Taylor, C De Vries, C Winkler
Space Science Center
The COMPTEL instrument aboard the COMPTEL Gamma-Ray Observatory and its performance capabilities are described. Calibration data are used to determine the angular and energy response, and the effective detection area. The imaging properties of COMPTEL are demonstrated, and the sensitivity of Comptel to celestial gamma-ray sources are estimated from flight data.
Preliminary Results From Comptel On A Search For Gamma-Ray Line Emission From Sn 1991t, G G. Lichti, K Bennett, H Bloemen, H Deboer, M Busetta, W Collmar, A Connors, R Diehl, R Van Dijk, J W. Den Herder, W Hermsen, L Kuiper, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, V. Schonfelder, G. Simpson, J G. Stacy, H Steinle, A W. Strong, B Swanenburg, M Varendorff, C De Vries, C Winkler
Preliminary Results From Comptel On A Search For Gamma-Ray Line Emission From Sn 1991t, G G. Lichti, K Bennett, H Bloemen, H Deboer, M Busetta, W Collmar, A Connors, R Diehl, R Van Dijk, J W. Den Herder, W Hermsen, L Kuiper, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, V. Schonfelder, G. Simpson, J G. Stacy, H Steinle, A W. Strong, B Swanenburg, M Varendorff, C De Vries, C Winkler
Physics & Astronomy
The COMPTEL experiment aboard the Compton Gamma-Ray Observatory is designed to image celestial gamma-radiation in the energy range from 0.7-30 MeV. With a field of view of 1 sr it is capable of locating strong point sources with an accuracy of better than 0.5 deg. From June 15 to 28, 1991 and a second time from October 3 to 17, 1991 the region containing the supernova SN 1991T was observed by COMPTEL. Here preliminary results from these observations are presented, with special attention to a search for gamma-ray line emission from the supernova.
Comptel Detections Of The Quasars 3c 273 And 3c 279, W Hermsen, H Aarts, K Bennett, H Bloemen, H Deboer, W Collmar, A Connors, R Diehl, R Vandijk, J W. Den Herder, L Kuiper, G G. Lichti, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, James M. Ryan, V. Schonfelder, G. Simpson, H Steinle, A W. Strong, B Swanenburg, C De Vries, W Webber, O R. Williams, C Winkler
Comptel Detections Of The Quasars 3c 273 And 3c 279, W Hermsen, H Aarts, K Bennett, H Bloemen, H Deboer, W Collmar, A Connors, R Diehl, R Vandijk, J W. Den Herder, L Kuiper, G G. Lichti, J Lockwood, John R. Macri, Mark L. Mcconnell, D Morris, James M. Ryan, V. Schonfelder, G. Simpson, H Steinle, A W. Strong, B Swanenburg, C De Vries, W Webber, O R. Williams, C Winkler
Physics & Astronomy
The COMPTEL experiment aboard the Compton Gamma Ray Observatory, sensitive in the energy range from about 0.7 to 30 MeV, observed the high-latitude region containing 3C 273 and 3C 279 during a 2-week period in June, 1991. A search for sources using a maximum likelihood analysis revealed two statistically significant point-like excesses, the positions of which are consistent with those of 3C 273 and 3C 279. These sources are the first QSOs detected at MeV energies. In the COMPTEL energy domain their spectra appear to be greatly different. A comparison with earlier and simultaneous measurements in neighboring energy ranges indicates …
The Crab And Galactic Anticentre Region Observed By Comptel, A W. Strong, K Bennett, H Bloemen, H Deboer, R Buccheri, M Busetta, W Collmar, A Connors, R Diehl, J W. Den Herder, W Hermsen, L Kuiper, J Lockwood, G G. Lichti, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, V. Schonfelder, G. Simpson, J G. Stacy, H Steinle, B Swanenburg, M Varendorff, C Winkler, C De Vries
The Crab And Galactic Anticentre Region Observed By Comptel, A W. Strong, K Bennett, H Bloemen, H Deboer, R Buccheri, M Busetta, W Collmar, A Connors, R Diehl, J W. Den Herder, W Hermsen, L Kuiper, J Lockwood, G G. Lichti, John R. Macri, Mark L. Mcconnell, D Morris, R Much, James M. Ryan, V. Schonfelder, G. Simpson, J G. Stacy, H Steinle, B Swanenburg, M Varendorff, C Winkler, C De Vries
Physics & Astronomy
The Galactic anticenter region including the Crab nebula has been observed with the COMPTEL gamma-ray telescope on the Gamma Ray Observatory. A map of the region in the 1-30 MeV energy range is presented. The total spectrum of the Crab is derived as well as that of the pulsed and unpulsed components. Upper limits on the pulsar Geminga are also presented.
The Gamma-Ray Burst Of 3 May 1991 Observed By Comptel On Board Gro, C Winkler, K Bennett, H Bloemen, W Collmar, A Connors, R Diehl, J W. Den Herder, W Hermsen, R M. Kippen, L Kuiper, G G. Lichti, J Lockwood, Mark L. Mcconnell, D Morris, James M. Ryan, V. Schonfelder, J G. Stacy, H Steinle, A W. Strong, B Swanenburg, B G. Taylor, M Varendorff, C De Vries
The Gamma-Ray Burst Of 3 May 1991 Observed By Comptel On Board Gro, C Winkler, K Bennett, H Bloemen, W Collmar, A Connors, R Diehl, J W. Den Herder, W Hermsen, R M. Kippen, L Kuiper, G G. Lichti, J Lockwood, Mark L. Mcconnell, D Morris, James M. Ryan, V. Schonfelder, J G. Stacy, H Steinle, A W. Strong, B Swanenburg, B G. Taylor, M Varendorff, C De Vries
Physics & Astronomy
The Compton Gamma-Ray Observatory was launched on April 5, 1991, carrying the imaging Compton telescope COMPTEL. Since its activation on April 25, 1991, COMPTEL has observed several gamma-ray bursts in its 1-sr field of view. The strongest of these bursts was observed on May 3, 1991. Event data over 0.8 MeV to 30 MeV as well as time resolved spectra over 0.1 MeV to 10 MeV have been recorded. For the first time, a direct single-telescope MeV image of a cosmic gamma-ray burst has been produced. The burst is located at (l,b) = (171.8 deg, 6.4 deg) with a statistical …