Calculation of ¹⁰Be & ¹⁴C Production Rates in the Solar Atmosphere: Implications for Solar Flare Spectral Index

Glynn E. Bricker

Department of Physics, Purdue University North Central, Westville, USA.

DOI: 10.4236/ijaa.2013.32A003                

Abstract

Production rates for the short-lived radionuclides ¹⁰Be (T_1/2=1.36Myr) and¹⁴C(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 ¹⁰Be and¹⁴Cflux rate at the surface of the Sun to range from 0.007 cm^﹣2.s^﹣1 to 2.55 cm^﹣2.s^﹣1 for ¹⁰Be, and from 0.13 cm^﹣2.s^﹣1 to 24.13 cm^﹣2.s^﹣1 for¹⁴C. These radio-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.

Keywords

Solar Wind; Radio-Nuclide; ¹⁰Be; ¹⁴C; Solar Flare Parameter

Conflicts of Interest

The authors declare no conflicts of interest.

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