Solar Gamma Ray Lines observed during the Solar Activity of August 2 to August 11, 1972

The Acceleration and Propagation of Solar Flare Energetic Particles

“…Shea andSmart 1973, Duggal 1979) and its interactions at the Sun are manifest in gamma-ray lines (Chupp et al 1973, Ramaty, Kozlovsky and Lingenfelter• 1975. Relativistic electrons are observed directly in interplanetary space (Simnett 1971, Datlowe 1971, Evenson, Meyer and Yanagita 1981 and their interactions at the Sun produce gamma-ray continuum (Suri et al 1975) and Type IV radio emission (e.g.…”

“…This question was studied (Bai andRamaty 1976, Lin andHudson 1976) for the August 4, 1972 flare which was the first flare from which nuclear gaiMna-rays were seen (Chupp et al 1973) .…”

Astrophysical Gamma Ray Emission Lines

“…Gamma ray lines from solar flares were first observed in 1972 with the NaI scintillator on OSO-7 (Chupp et al 1973). But it was not until 1980 that routine observations of gamma ray lines and continuum became possible with the much more sensitive NaI spectrometer on the Solar Maximum Mission (SMM, Rieger 1989;Chupp 1990).…”

“…The observation of such line emission provides unique information on processes of nucleosynthesis. Nuclear deexcitation lines following accelerated particle interactions have been observed from solar flares (Chupp et al 1973;Rieger 1989;Chupp 1990) and recently from the Orion molecular cloud complex with the COMPTEL imaging spectrometer on the Compton Gamma Ray Observatory (CGRO, Bloemen et al 1994). The observed Orion lines, at 4.44 MeV from 12 C and 6.13 MeV from 16 O, cannot result from processes of nucleosynthesis since there are no significant long lived radioactive isotopes that decay into the excited states of these nuclei.…”

Nuclear Processes in Solar Flares

“…The August 4 and August 7, 1972 events were observed by Chupp et al (1973) with the spectrometer on board OSO-7. The data given in Table 2 for the August 4, 1972 flare is from Chupp (1976), except for f(4-7 MeV) which is from the analysis of Ramaty, .…”