Ⅱ-1. Nuclear Physics
RIKEN
Accel. Prog. Rep. 56 (2023)

RIKEN Accel. Prog. Rep. 56 (2023)

Analysis of 48 Cr(p, n) reaction in inverse kinematics
M. Sasano,∗1 J. Gao,∗1,∗3 L. Stuhl,∗9,∗22 Y. Hirai,∗4 T. Wakasa,∗4 D. S. Ahn,∗1 J. K. Ahn,∗13 H. Baba,∗1K. Chae,∗20 A. Chilug,∗5,∗1 K. Cook,∗15 Y. Fujino,∗7 N. Fukuda,∗1 B. Gao,∗19 S. Goto,∗4 I. S. Hahn,∗8,∗22
Y. Hamano,∗4 Z. Halász,∗9 T. Harada,∗10,∗1 S. Hong,∗20 S. Huang,∗1,∗3 N. Inabe,∗1 D. Inomoto,∗4 T. Isobe,∗1H. Kasahara,∗4 D. Kim,∗8 T. Kobayashi,∗14,∗1 Y. Kondo,∗15,∗1 Z. Korkulu,∗1 A. Krasznahorkai,∗9 H. Miki,∗15K. Miki,∗14,∗1 S. Mitsumoto,∗4 M. Miwa,∗18,∗1 T. Motobayashi,∗1 T. Nakamura,∗15,∗1 M. Nishimura,∗1H. Oshiro,∗4 H. Otsu,∗1 V. Panin,∗1 S. Sakaguchi,∗4,∗1 D. Sakai,∗14 H. Sakai,∗1 S. Sakaki,∗4 H. Sato,∗1T. Shimada,∗15 Y. Shimizu,∗1 B. Sun,∗21 X. Sun,∗1,∗3 H. Suzuki,∗1 J. Tanaka,∗1 Y. Togano,∗7,∗1 T. Tomai,∗15,∗1T. Uesaka,∗1 Y. Utsuki,∗14 H. Wang,∗15,∗1 X. Xu,∗19 K. Yako,∗2 A. Yasuda,∗15 K. Yoneda,∗1 K. Yoshida,∗1Y. Yoshitome,∗15 and J. Zenihiro∗1
In this paper, we report on the progress in the dataanalysis of the SAMURAI11 experiment performed at
the RI Beam Factory (RIBF) of RIKEN Nishina Center in spring, 2019. This experiment was conducted
to measure the (p, n) reaction on N = Z unstable nuclei, namely, 48 Cr and 64 Ge. Previously, in Refs. 1)
and 2), we reported on the experimental setup and theparticle identiﬁcation (PID) analysis of the reaction
residues with the SAMURAI spectrometer,3) respectively. In Ref. 4), we reported on the observation ofa kinetic curve in the recoil-neutron data produced in
the 48 Cr(p, n)48 Mn reaction, under the condition thatthe reaction residues 47 Cr were selected through PID
analysis.
Figure 1 shows a plot of neutron kinetic energy
vs. neutron scattering angle in the laboratory frame
for those events in which the reaction residues 46 V
were selected through PID analysis. The 46 V residues
were populated through the two-proton decay from the48Mn. There was no clear locus along the calculated
kinetic curves in 48 Mn, above the two-proton separation energy at 6.828 MeV. The plot contains events
due to the background in a low neutron-kinetic-energy
region below 500 keV.
A further analysis is ongoing to substract the back-Fig. 1. A two-dimensional plot of neutron kinetic energy vs.
neutron scattering angle in the laboratory frame. The
reaction residues 46 V were selected through the PID
analysis. The solid and dashed curves represent calculated kinetic curves for excitation energies and scattering angles in the center-of-mass system of the 48 Cr(p, n)reaction, respectively.

ground. We are working on the background evaluationby using the reaction channels where the (p, n) reaction does not occur, following the method utilized in aprior study.5)
We are grateful to the RIKEN accelerator staﬀ andCNS, University of Tokyo, for their continuous eﬀorts
to accomplish this stable beam acceleration.

∗1RIKEN Nishina Center∗2 Center for Nuclear Study, University of Tokyo∗3 School of Physics, Peking University∗4 Department of Physics, Kyushu University∗5 Horia Hulubei National Institute for R&D in Physics andNuclear Engineering∗7 Department of Physics, Rikkyo University∗8 Department of Physics, Ewha Womans University∗9 Institute for Nuclear Research (ATOMKI)∗10 Department of Physics, Toho University∗11 KVI - CART, University of Groningen∗12 GSI Helmholtzzentrum für Schwerionenforschung GmbH
∗13 Department of Physics, Korea University∗14 Department of Physics, Tohoku University∗15 Department of Physics, Tokyo Institute of Technology∗16 Department of Physics, University of Tokyo∗18 Department of Physics, Saitama University∗19 Institute of Modern Physics, Chinese Academy of Sciences∗20 Department of Physics, Sungkyunkwan University∗21 School of Physics and Nuclear Engineering, Beihang University∗22 Center for Exotic Nuclear Studies, Institute for Basic Science

References
1) M. Sasano et al., RIKEN Accel. Prog. Rep. 53, 40(2019).
2) J. Gao et al., RIKEN Accel. Prog. Rep. 54, 14 (2020).
3) T. Kobayashi et al., Nucl. Instrum. Methods Phys. Res.
B 317, 294 (2013).
4) M. Sasano et al., RIKEN Accel. Prog. Rep. 55, 22(2022).
5) M. Sasano et al., Phys. Rev. C 86, 034324 (2012).

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