Zakopane 2026 Conference on Nuclear Physics

In this invited contribution, I will present recent results from $(d,p)$ experiments performed with the Super-Enge Split-Pole Spectrograph at the John D. Fox Accelerator Laboratory of Florida State University [1] to study single-particle strengths in $fp$-shell nuclei [2-4]. After briefly highlighting the capabilities of the experimental setup [1,5], I will focus on three specific examples. First, I will provide a brief overview on our results obtained for the neutron-adding strengths in the $N=29$ isotone $^{53}$Cr [3], comparing to strengths measured earlier for $^{55}$Fe [6]. Then, I will pivot and focus on the rich dataset which we obtained for $^{50}$Ti. I will briefly point out similarities and differences between the fragmentation of neutron-adding strengths for excited states of even-$A$ $^{50}$Ti and odd-$A$ $^{51}$Ti, before I discuss $1^+$ and $1^-$ states of $^{50}$Ti populated in the $(d,p)$ reaction. By comparing to observables obtained from complementary experiments, I will make a case for how $(d,p)$ can be used to study the microscopic origin of the spin-flip $M1$ resonance [4] and of the low-energy $E1$ strength, often referred to as pygmy dipole resonance (PDR) [2,7].

The experimental program at the FSU John D. Fox Laboratory is supported by the U.S. National Science Foundation (PHY-2412808 and PHY-2405485) and by the U.S. National Nuclear Security Administration (DE-NA0004150) as part of CENTAUR. Support from Florida State University is gratefully acknowledged.

References:

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