Gamma ray astronomy in the low energy range

A low energy gamma ray telescope, and the results of its observations are described. The telescope consisted of four sodium iodide crystals, each of 120 cm² area, occulted by lead discs. Charged particles are rejected using scintillation, anti-coincidence shields.<br/><br/>The telescope was flown from Palestine, Texas in 1974. Gamma rays were observed from the Crab Nebula, the pulsar NP0 532, and the atmospheric background. No evidence for a gamma ray burst was found, giving an upper limit of less than 5.8 x 10³ bursts per year of intensity greater than 1.6 x 10^-6 ergs cm^-2.<br/><br/>Various types of existing, and planned, gamma ray detectors, and successful gamma ray observations are reviewed. Detailed calculations of the detection efficiency of a Double Compton telescope are presented and these results led to the development of the MISO low energy gamma ray telescope.<br/><br/>Preliminary calculations of the detection efficiency of an Anticollimated Double Compton telescope are presented, which suggest that further, more detailed investigation of this type of detector would prove fruitful.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

1979

Author dc:creator

• Bailey, E.P.A.