Lifetimes of states in [superscript 19]Ne above the [superscript 15]O+[alpha] breakup threshold

Abstract

The [superscript 15]O([alpha], [lambda])[superscript 19]Ne reaction plays a role in the ignition of type I x-ray bursts on accreting neutron stars. The lifetimes of states in [superscript 19]Ne above the [superscript 15]O+[alpha] threshold of 3.53 MeV are important inputs to calculations of the astrophysical reaction rate. These levels in [superscript 19]Ne were populated in the [superscript 3]He([superscript 20]Ne, [alpha])[superscript 19]Ne reaction at a [superscript 20]Ne beam energy of 34 MeV. The lifetimes of six states above the threshold were measured with the Doppler-shift attenuation method. The present measurements agree with previous determinations of the lifetimes of these states and in some cases are considerably more precise.