Particle and Nuclear Physics Seminar at J-PARC

(J-PARC 素粒子原子核セミナー)


DATE: 2017. June. 12th. 13:40-

PLACE: Tokai 1st Building Room 116

TITLE:
Competing effects of nuclear deformation and hyperonic many-body force on Lambda binding energy


LANGUAGE: English

SPEAKER:
Prof. Masahiro Isaka (Osaka Univ. RCNP Center)
CONTACT: Dr. Kazuya Aoki,
j-parc-pn-seminar-(AT)-ml.post.kek.jp




Abstract:

In this talk, I will discuss competitive effects between nuclear deformation and density dependence of Lambda N interaction in Lambda binding energies $B_\Lambda$ of hypernuclei on the basis of the baryon-baryon interaction model ESC (extended soft core). Since Lambda hypernuclei in p-, sd- and pf-shell mass regions have various structures in the ground states, the density dependence of the Lambda-N interaction can affect the systematics of the $B_\Lambda$ values. Recently, many authors discuss hyperonic many-body force acting not only on nucleonic but also hyperonic channels at high density, related to so-called hyperon puzzle, which is suggested by the stiff equation-of-state giving the neutron-star mass. Due to the strong density dependence of hyperonic many-body force, it can affect the systematic data of the B_\Lambda values.
To see such effects, we perform microscopic calculations of Lambda hypernuclei with 9 \le A \le 59 within the framework of the antisymmetrized molecular dynamics by using the Lambda N G-matrix interaction derived from ESC including many-body force effects. We found that proper description of hypernuclear structure, especially nuclear deformation, is indispensable to see the effects on the B_\Lambda values. In this talk, I will discuss the effects by the hyperonic many-body force in B_\Lambda values as well as importance of describing nuclear def