Abstract
Background: The Doppler broadening of -ray peaks due to nuclear recoil from -delayed nucleon emission can be used to measure the energies of the nucleons. This method has never been tested using -delayed proton emission or applied to a recoil heavier than .
Purpose: To test and apply this Doppler broadening method using -ray peaks from the decay sequence.
Methods: A fast beam of was implanted into a planar Ge detector, which was used as a -decay trigger. The SeGA array of high-purity Ge detectors was used to detect rays from the decay sequence.
Results: Radiative Doppler broadening in -delayed proton- decay was observed for the first time. The Doppler broadening analysis method was verified using the 1613-keV -ray line for which the proton energies were previously known. The 1776-keV ray de-exciting the 2720 keV level was observed in decay for the first time and used to determine that the center-of-mass energy of the proton emission feeding the 2720-keV level is (stat.) (syst.) MeV, corresponding to a excitation energy of (stat.) (syst.) MeV for the proton-emitting level.
Conclusions: The Doppler broadening method has been demonstrated to provide practical measurements of the energies for -delayed nucleon emissions populating excited states of nuclear recoils at least as heavy as .
- Received 24 July 2015
DOI:https://doi.org/10.1103/PhysRevC.92.031302
©2015 American Physical Society