Currently, the explanation behind the explosion mechanism of core collapse supernovae is yet to be fully understood. New insight to this phenomena may come through observations of 44Ti cosmic gamma rays; this technique compares the observed flux of cosmic 44Ti gamma rays to that predicted by state-of-the-art models of supernova explosions. In doing so, the mass cut point of the star can be found. However, a road block in this procedure comes from a lack of precision in the nuclear reactions that destroy 44Ti in supernovae, most notably the reactions 44T(alpha,p)47V and 45V(p,gamma)46Cr. Therefore, this study aims to better understand the 45V(p,gamma)46Cr reaction by performing gamma-ray spectroscopy of 46Cr with the aim of identifying proton-unbound resonant states.
The experiment was conducted at the ATLAS facility at Argonne National Laboratory, using the GRETINA+FMA setup, where 46Cr was produced via the fusion-evaporation reaction 12C(36Ar,2n). The cross section for producing 46Cr, in this reaction, is estimated to be in the mu b range. Nevertheless, with the power of the GRETINA+FMA setup, we show that it is possible to cleanly identify gamma rays in 46Cr. These include decays from previously unidentified states above the proton-emission threshold, corresponding to resonances in the 45V + p system.