1–6 Sept 2019
University of Surrey
Europe/London timezone

Measurement of Spin Correlation Coefficients in ${\it p-}$$^{3}$He Scattering at 65 MeV

2 Sept 2019, 16:20
20m
University of Surrey

University of Surrey

Speaker

Ms Minami Inoue (Tohoku univ., Japan)

Description

Few-nucleon scattering offers good opportunities to investigate dynamical aspects of the three-nucleon forces (3NFs), such as momentum, spin, and iso-spin dependencies. The nucleon-deuteron scattering at intermediate energies ($E/A \sim 100~\rm MeV$) has provided a solid basis to nail down detailed properties of 3NFs [1.], however, the total isospin channel of the 3NFs is limited to ${\it T =}$ 1/2. Recently importance of the iso-spin dependence of 3NFs has also been pronounced for understanding of nuclear system with larger-isospin asymmetry, e.g. neutron-rich nuclei [2.] and neutron matter [3.]. The ${\it p-}$$^{3}$He scattering is an attractive probe since this system is the simplest one in which the 3NFs in the channels of total isospin ${\it T =}$ 3/2 can be studied. In order to explore the properties of three-nucleon forces via ${\it p-}$$^{3}$He scattering, we have performed the measurements of spin observables at 65 MeV by using the newly developed polarized $^{3}$He target and the polarized proton beam.

The experiment was performed at RCNP, Osaka University. Polarized proton beams were accelerated up to 65 MeV by the AVF cyclotron, and bombarded the polarized $^{3}$He target. The typical beam polarization was $p_{y}^{\uparrow}\sim50\%$, $p_{y}^{\downarrow}\sim20\%$. The scattered protons were detected by ${\it E-dE}$ detectors which consisted of NaI(Tl) and plastic scintillators. The measured angles were 47, 89, and 133 degrees in the center of mass system.

The results of the spin correlation coefficient $C_{y,y}$ are shown in Fig.1. The statistical errors are shown only. The data are compared with the rigorous numerical calculation of the four-nucleon scattering based on the modern nucleon-nucleon potential [4.]. Here the INOY04 potential [5.] is taken into account. Clear differences are found around 90 degree.

[1.] K. Sekiguchi ${\it et~al.}$, Phys. Rev. C ${\bf 65}$, 034003 (2002).

[2.] S. C. Pieper ${\it et~al.}$, Phys. Rev. C ${\bf 64}$, 014001 (2001).

[3.] A. Gandolfi, ${\it et~al.}$, Phys Rev C ${\bf 85}$, 032801 (2012).

[4.] A. Deltuva, private communications.

[5.] P. Doleschall, Phys Rev. C ${\bf 69}$, 054001 (2004).

The results of  the spin correlation coefficient.

Primary author

Ms Minami Inoue (Tohoku univ., Japan)

Co-authors

Prof. Kimiko Sekiguchi (Tohoku univ., Japan) Prof. Kenjiro Miki (Tohoku univ., Japan) Mr Atom Watanabe (Tohoku univ., Japan) Mr Shinnosuke Nakai (Tohoku univ., Japan) Mr Shun Shibuya (Tohoku univ., Japan) Mr Daisuke Sakai (Tohoku univ., Japan) Mr Yuta Utsuki (Tohoku univ., Japan) Prof. Kichiji Hatanaka (RCNP Osaka univ., Japan) Prof. Hiroki Kanda (RCNP Osaka univ., Japan) Prof. Hooi Jing Ong (RCNP Osaka univ., Japan) Prof. Tomotsugu Wakasa (Kyusyu univ., Japan) Mr Shuhei Goto (Kyusyu univ., Japan) Mr Shinji Mitsumoto (Kyusyu univ., Japan) Mr Daiki Inomoto (Kyusyu univ., Japan) Ms Hina Kasahara (Kyusyu univ., Japan) Dr Takashi Ino (KEK, Japan) Dr Hideyuki Sakai (RIKEN, Japan) Prof. Yukie Maeda (Miyazaki univ., Japan) Mr Kotaro Nonaka (Miyazaki univ., Japan) Dr Takashi Wakui (NIRS, Japan) Prof. Masatoshi Itoh (CYRIC Tohoku univ., Japan)

Presentation materials