The Hard X-Ray Burst Spectrometer on the Solar Maximum Mission

✍ Scribed by L. E. Orwig; K. J. Frost; B. R. Dennis

• Publisher: Springer
• Year: 1980
• Tongue: English
• Weight: 740 KB
• Volume: 65
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00151382

✦ Synopsis

The primary scientific objectives of the Hard X-Ray Burst Spectrometer (HXRBS) to be flown on the Solar Maximum Mission are as follows: (1) To determine the nature of the mechanisms which accelerate electrons to 20-100 keV in the first stage of a solar flare and to > 1 MeV in the second stage of many flares; and (2) to characterize the spatial and temporal relation between electron acceleration, storage and energy loss throughout a solar flare.

Measurements of the spectrum of solar X-rays will be made in the energy range from 20 to 260 keV using an actively-shielded CsI(Na) scintillator with a thickness of 0.635 cm and a sensitive area of 71 cm 2. Continuous measurements with a time resolution of 0.128 s will be made of the 15-channel energy-loss spectrum of events in this scintillator in anticoincidence with events in the CsI(Na) shield. Counting-rate data with a time resolution as short as 1 ms will also be available from a limited period each orbit using a 32K-word circulating memory triggered by a high event rate.

In the first year after launch, it is expected that approximately 1000 flares will be observed above the instrument sensitivity threshold, which corresponds to a 20-200keV X-ray flux of 2 x 10 -1 photons (cm x s) -1 lasting for at least one second.