Calculation of <sup>10</sup>Be & <sup>14</sup>C Production Rates in the Solar Atmosphere: Implications for Solar Flare Spectral Index
- 1 Department of Physics, Purdue University North Central, Westville, USA
Abstract
Production rates for the short-lived radionuclides 10 Be (T 1/2 =1.36Myr) and 14 C(T 1/2 =5730 yr) in the solar atmosphere were calculated. As both radionuclides are produced through spallation reaction of solar energetic particles (SEP) with oxygen as the primary target, the prevalence of each radionuclide is linked. For the calculations, we assumed power law distribution for SEP with spectral index, r , ranging from 2.5 to 4. We find the 10 Be and 14 Cflux rate at the surface of the Sun to range from 0.007 cm ﹣2. s ﹣1 to 2.55 cm ﹣2. s ﹣1 for 10 Be, and from 0.13 cm ﹣2. s ﹣1 to 24.13 cm ﹣2. s ﹣1 for 14 C. These ra dio-nuclides are then entrained in the solar wind. From these flux rate calculations and comparison with experimentally measured flux rates ,we find the most likely time averaged solar flare spectral index to be r = ~3.3.
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