DETERMINATION OF THE THERMAL-NEUTRON INDUCED CA-41(N,P)K-41 AND CA-41(N,ALPHA)AR-38 REACTION CROSS-SECTIONS

The Ca-41(n,p)K-41 and Ca-41(n,alpha)Ar-38 reaction cross sections wer e determined with thermal neutrons at the high flux reactor of the ILL in Grenoble. For the Ca-41(n(th),p)K-41 reaction cross section, a val ue of (7+/2) mb was obtained. In the case of the Ca-41(n(th),alpha)Ar- 38 reaction, the transition to the ground state in Ar-38 has a cross s ection sigma(n(th),alpha(0)) = (42+/-6) mb, the most prominent decay g oing to the first excited state in Ar-38 with a cross section sigma(n( th),alpha(1)) = (130+/-25) mb. This can be explained by the presence o f a nearby bound level with J(pi) = 4(-). Also Ca-41(n(th),gamma alpha ) Ar-38 transitions have been observed with a cross section of (10+/-2 ) mb. The primary gamma transitions are shown to have a M1 multipolari ty.