Measurements of proton-induced production cross sections for 36Cl from Ca and K

Abstract Production cross sections for 36 Cl (half-life = 3.01 × 10 5 y) have been measured for the nat.K(p, x ), 39 K(p, x ), nat.Ca(p, x ) and 40 Ca(p, x ) reactions up to 40 MeV. The results of nat.Ca(p, x ) reaction are generally consistent with measurements performed at somewhat higher energies. With the completion of these measurements it is now possible to proceed with model calculations of the solar cosmic ray (SCR) flux over the last 400 ky based on measurements of lunar surface materials.