Phys.Rev. C 100, 032801(R) (2019)

J.C.Zamora, R.G.T.Zegers, SamM.Austin, D.Bazin, B.A.Brown, P.C.Bender, H.L.Crawford, J.Engel, A.Falduto, A.Gade, P.Gastis, B.Gao, T.Ginter, C.J.Guess, S.Lipschutz, B.Longfellow, A.O.Macchiavelli, K.Miki, E.Ney, S.Noji, J.Pereira, J.Schmitt, C.Sullivan, R.Titus, D.Weisshaar

Experimental constraint on stellar electron-capture rates from the ⁸⁸Sr(t, ³He + γ) ⁸⁸Rb reaction at 115 MeV/u

NUCLEAR REACTIONS ⁸⁸Sr(t, ³He)⁸⁸Rb, E=115 MeV/nucleon, [secondary triton beam from ⁹Be(¹⁶O, X), E=150 MeV/nucleon using Coupled Cyclotron Facility and A1900 fragment separator at NSCL-MSU]; measured ³He ejectiles, angular distributions using S800 spectrograph, and Eγ, Iγ using GRETINA array; deduced double-differential cross sections, L-transfers from fitting of the σ(θ) distributions in the multipole decomposition analysis (MDA), two-dimensional histogram of γ-ray energy versus excitation energy of ⁸⁸Rb. ⁸⁸Sr; deduced B(GT) strength distributions, electron capture (EC) rates on ⁸⁸Sr as a function of stellar density at a temperature of 10 GK. ^86,87,88Rb; deduced transitions. ¹²C(t, ³He)¹²B, E=115 MeV/nucleon; measured ³He ejectiles, reaction used for calibration and for absolute measurement of the triton beam intensity. Comparison of experimental EC rates on ⁸⁸Sr with shell model and QRPA calculations. Relevance to the late evolution of core-collapse supernovae.

doi: 10.1103/PhysRevC.100.032801