Spectroscopic investigation of \(^{54}\)Cr via \(\alpha \)-transfer reaction

Low-lying states in \(^{54}\)Cr have been investigated via the \(\alpha \)-transfer reaction \(^{50}\)Ti(\(^{7}\)Li,t) at a bombarding energy of 20 MeV. The exclusive \(\alpha \)-transfer channel is separated from other reaction channels through the appropriate energy gate on the complementary particle, triton. Levels of \(^{54}\)Cr populated exclusively by the \(\alpha \)-transfer process could be identified up to \(\approx \) 5 MeV excitation energy and angular momentum up to \((8)^{+}\), by identifying the corresponding known \(\gamma \)-rays. These include multiple low-lying non-yrast 2\(^+\) and 4\(^+\) states, which would otherwise be unfavorable via fusion evaporation reactions. The feeding-subtracted \(\gamma \)-ray yields have been extracted to estimate the population of various excited states through the transfer process. The measured integrated transfer cross sections for all the observed yrast and non-yrast states are compared with Coupled Channels calculations using fresco to extract the \(\alpha \)+\(^{50}\)Ti core spectroscopic factors. For the yrast states, a higher \(\alpha \)+core overlap is seen for the \(2^+\) and \(4^+\) states, while it is seen to be less favorable for the \(6^+\) and \((8)^+\) states when \(\alpha \)-transfer is considered to occur predominantly as a direct one-step process to the \(^{50}\)Ti core ground state. The yrast \(2^+\), and \(4^+\) states are predominantly populated by single-step transfer, while for the states with spin \(\ge \) 5, the possibility of core excitation followed by \(\alpha \)-transfer shows a larger \(\alpha \)-core overlap. For the non-yrast \(0^+\), \(2^+\), and \(4^+\) states, single-step transfer shows moderate to small \(\alpha \)-core overlap. No higher spin non-yrast states are observed.