Experimental study of-delayed proton decay ofAl23for nucleosynthesis in novae Academic Article uri icon


  • The -delayed and proton decay of Al23 has been studied with an alternative detector setup at the focal plane of the momentum achromat recoil separator MARS at Texas A&M University. We could detect protons down to an energy of 200 keV and determine the corresponding branching ratios. Contrary to results of previous -decay studies, no strong proton intensity from the decay of the isobaric analog state (IAS) of the Al23 ground state at E x=7803 keV in Mg23 was observed. Instead we assign the observed low-energy group Ep,c.m.=206 keV to the decay from a state that is 16 keV below the IAS. We measured both proton and gamma branches from the decay of this state at Ex=7787 keV in Mg23, which is a very rare case in the literature. Combining our data with its measured lifetime, we determine its resonance strength to be =1.4-0.4+0.5 meV. The value is in agreement with older direct measurements, but disagrees with a recent direct measurement. This state is the most important resonance for the radiative proton capture Na22(p,)Mg23 in some astrophysical environments, such as novae. 2011 American Physical Society.

published proceedings

  • Physical Review C

author list (cited authors)

  • Saastamoinen, A., Trache, L., Banu, A., Bentley, M. A., Davinson, T., Hardy, J. C., ... yst, J.

citation count

  • 41

complete list of authors

  • Saastamoinen, A||Trache, L||Banu, A||Bentley, MA||Davinson, T||Hardy, JC||Iacob, VE||McCleskey, M||Roeder, BT||Simmons, E||Tabacaru, G||Tribble, RE||Woods, PJ||Äystö, J

publication date

  • April 2011