Physical Sciences and Mathematics Commons^™

Characteristics Of Ion Flow In The Quiet Inner Plasma Sheet, V. Angelopoulos, C. F. Kennel, F. V. Coroniti, R. Pellat, Harlan E. Spence, Margaret G. Kivelson, Raymond J. Walker, W. Baumjohann, W. C. Feldman, J. T. Gosling, C. T. Russell

Physics & Astronomy

Abstract

We use AMPTE/IRM and ISEE 2 data to study the properties of the high beta (β_i > 0.5) plasma sheet, the inner plasma sheet (IPS). Bursty bulk flows (BBFs) are excised from the two databases, and the average flow pattern in the non-BBF (quiet) IPS is constructed. At local midnight this ensemble-average flow is predominantly duskward; closer to the flanks it is mostly earthward. The flow pattern agrees qualitatively with calculations based on the Tsyganenko [1987] model (T87), where the earthward flow is due to the ensemble-average cross tail electric field and the duskward flow is the diamagnetic drift …

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.

Contributions Of The Low-Latitude Boundary Layer To The Finite Width Magnetotail Convection Model, Harlan E. Spence, M. G. Kivelson

Physics & Astronomy

Convection of plasma within the terrestrial nightside plasma sheet contributes to the structure and, possibly, the dynamical evolution of the magnetotail. In order to characterize the steady state convection process, we have extended the finite tail width model of magnetotail plasma sheet convection. The model assumes uniform plasma sources and accounts for both the duskward gradient/curvature drift and the earthward E × B drift of ions in a two-dimensional magnetic geometry. During periods of slow convection (i.e., when the cross-tail electric potential energy is small relative to the source plasma's thermal energy), there is a significant net duskward displacement of …

Comptel Observations Of The 1.809 Mev Gamma-Ray Line From Galactic 26al, R Diehl, C. Dupraz, K Bennett, H Bloemen, H Deboer, W Hermsen, G G. Lichti, Mark L. Mcconnell, D Morris, James M. Ryan, V. Schonfelder, H Steinle, A W. Strong, B Swanenburg, M Varendorff, C Winkler

Physics & Astronomy

No abstract provided.

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 …

First Results From Comptel Measurement Of The Al-26 1.8 Mev Gamma-Ray Line From The Galactic Center Region, R Diehl, K Bennett, H Bloemen, H Deboer, M Busetta, W Collmar, A Connors, J W. Den Herder, C. Devries, W Hermsen, J Knodlseder, L Kuiper, G G. Lichti, 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, P. Von Ballmoos, W Webber, C Winkler

Physics & Astronomy

The COMPTEL instrument on GRO is designed to image celestial gamma radiation in the approximately 0.7-30 MeV region of nuclear lines. Within a large field of view of about 1 sr its angular resolution of about 1 deg enables mapping of extended emission and location of (strong) point sources to an accuracy of better than 0.5 deg. The Galactic center region was observed by COMPTEL for a 2-week period in July 1991. Here we report the detection of the line at 1.8 MeV attributed to Al-26, addressing in particular the extent of the emission and the 1.8 MeV line flux.

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.

Comptel Observations Of The Crab And Vela Pulsars, K Bennett, H Aarts, H Bloemen, R Buccheri, M Busetta, W Collmar, A Connors, A Carramiñana, R Diehl, H Deboer, 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, A W. Strong, B Swanenburg, B G. Taylor, M Varendorff, C De Vries, W Webber, C Winkler

Physics & Astronomy

The COMPTEL gamma-ray telescope, sensitive in the range 0.7-30 MeV, has viewed the Crab and Vela Pulsars. The light curves observed from both objects have been derived in several energy bands. Features of these light curves and some spectral details are discussed.