LXX International conference "NUCLEUS – 2020. Nuclear physics and elementary particle physics. Nuclear physics technologies"

Particle-hole dispersive optical model for open-shell nuclei. Implementations for describing 0$^{+}$ giant resonances in tin isotopes

12 Oct 2020, 17:00

25m

Online

Oral report Section 1. Experimental and theoretical studies of the properties of atomic nuclei. Section 1. Experimental and theoretical studies of the properties of atomic nuclei

Speaker

Mr Georgy Kolomiytsev (National Research Nuclear University MEPhI)

Description

The semi-microscopic particle-hole dispersive optical model (PHDOM), in which main relaxation modes of high-energy particle-hole-type nuclear excitations are together taken into account [1], has been implemented for describing various giant resonances in medium-heavy closed-shell nuclei (see, e.g., Refs. [2,3]).
A lot of experimental data concerned with giant resonances in medium-heavy open-shell spherical nuclei makes reasonable an extension of PHDOM for taking nucleon pairing into account. In the present work, an extended PHDOM version is developed in a “high-energy limit” employing the simplest BCS-model.
The proposed version is implemented for describing main properties of Isoscalar Giant Monopole Resonance (ISGMR) and Isobaric Analog Resonance (IAR) in a number of tin isotopes.
From studies of ISGMR in a chain of tin isotopes one gets information about isotopic dependence of nuclear-matter incompressibility coefficient (see, e.g., Ref. [4]).
Existence and properties of IAR are closely related to the isospin and symmetry in nuclei. Using previous studies of ISGMR [2], IAR and its overtone [3] as a base, we employ the extended PHDOM version for describing strength function, projected transition density, probabilities of direct one-nucleon decay of ISGMR, and main relaxation parameters of IAR (partial proton and spreading widths, resonance-mixing phase).
The obtained results are compared with respective experimental data related to ISGMR (Ref. [4] and references therein) and IAR [5].
This work was partially supported by the Russian Foundation of Basic Research (grant No. 19-02-00660).

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   02125 (2018).
2. M.L. Gorelik, S. Shlomo, B.A. Tulupov and M.H. Urin, Nucl. Phys.
   A 955, 116 (2016); Nucl. Phys. A 970, 353 (2018).
3. G.V. Kolomiytsev, M.L. Gorelik, M.H. Urin, Eur. Phys. J. A 54,
   228 (2018).
4. U. Garg and G. Colò, Prog. Part. Nucl. Phys. 101, 55 (2018).
5. B.Ya. Guzhovskiy et al., Yad. Fiz. 21, 930 (1975).

Presentation materials

Gorelik_ML-0+GR-NUCLEUS-2020.pdf