Beta and gamma decays of J(pi)=1(+), Al-24m state beta and gamma branching ratios
EUROPEAN PHYSICAL JOURNAL A, cilt.47, sa.12, 2011 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 47 Sayı: 12
- Basım Tarihi: 2011
- Doi Numarası: 10.1140/epja/i2011-11155-7
- Dergi Adı: EUROPEAN PHYSICAL JOURNAL A
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- İstanbul Üniversitesi Adresli: Evet
Özet
A beta-gamma spectroscopy of the J(pi) = 1(+), 426 keV isomeric state of Al-24 ( Al-24m) has been carried out by using a Al-24 secondary beam with high purity and high isomeric ratio. From the absolute gamma-ray and beta-particle intensities observed in the decay of the isomeric state, the branching ratio R-B of the isomeric gamma-decay from Al-24m to the J(pi) = 4(+), ground state of Al-24 have been derived. The obtained R-B value of 69.6(7)% is much smaller than the previously accepted value of 82.5(30)%. The precise half-life for the isomer decay, T-1/2(m) = 130.9(13) ms, has been also determined in this experiment. Accordingly, the M3 gamma-decay strength B(M3) of the Al-24m decay becomes smaller and the total beta-decay branching ratio becomes larger. In particular, the beta-decay branching ratio to the ground state of Mg-24 becomes 24.3(9)%, which is 2.4 times larger than the previous value of 10.1(28)%. By combining the branching ratio and the half-life, the Gamow-Teller (GT) transition strength B(GT) of 0.0194(7) is deduced for the GT transition from Al-24m to the J(pi) = 0(+), ground state of Mg-24. This value is in good agreement with the values derived from charge-exchange reactions.