New！”Effective field theory for weakly bound two-neutron halo nuclei ”by Dr. Masaru Hongo, Associate Professor (Niigata University)

Tuesday Nov 4, 2025, 1:30 PM → 3:00 PM Asia/Tokyo

RIBF Hall, 2 Floor, RIBF bldg. (Wako Saitama)

Lecturer： Dr. Masaru Hongo, Associate Professor, Niigata University

講師： 本郷 優 氏,  新潟大学准教授

Place and Time：

4th November（Tuesday）13：30～  RIBF Coneference Hall

開催日時：

１１月４日 火曜日 １３時半より RIBF棟大会議室

Title: Effective field theory for weakly bound two-neutron halo nuclei 

Abstract:

We develop an effective field theory (EFT) framework for weakly bound two-neutron halo nuclei, or Borromean systems such as 22C, where the two-neutron separation energy and the neutron–neutron virtual energy constitute the lowest energy scales of the problem. At leading order, the EFT involves a single dimensionless coupling exhibiting universal scaling behavior. We demonstrate that key observables, including the ratio of matter and charge radii, the electric dipole (E1) strength function, and the electric polarizability, depend only on the ratio of these two energies, for which analytic expressions are obtained. We further investigate next-to-leading-order corrections arising from the neutron–neutron effective range and evaluate their impact on these observables. Our results establish a unified and systematically improvable EFT framework for describing the structure and electromagnetic response of two-neutron halo systems. 

Language: English

Reference

[1] M. Hongo, D. T. Son, Phys. Rev. Lett. 128, 212501 (2022), https://doi.org/10.1103/PhysRevLett.128.212501

[2] D. B. Costa, M. Hongo, D. T. Son, Phys. Rev. C 112, 014001 (2025), https://doi.org/10.1103/lds3-g3tp

20251104 RIBF Seminar Masaru Hongo.pdf