J 2021

Mass measurements of As, Se, and Br nuclei, and their implication on the proton-neutron interaction strength toward the N = Z line

MARDOR, I., S. Ayet SAN ANDRES, T. DICKEL, D. AMANBAYEV, S. BECK et. al.

Basic information

Original name

Mass measurements of As, Se, and Br nuclei, and their implication on the proton-neutron interaction strength toward the N = Z line

Authors

MARDOR, I., S. Ayet SAN ANDRES, T. DICKEL, D. AMANBAYEV, S. BECK, J. BERGMANN, H. GEISSEL, L. GROF, E. HAETTNER, C. HORNUNG, N. KALANTAR-NAYESTANAKI, G. KRIPKO-KONCZ, I. MISKUN, A. MOLLAEBRAHIMI, W. R. PLASS, C. SCHEIDENBERGER, H. WEICK, Soumya BAGCHI, D. L. BALABANSKI, Andrey BEZBAKH (643 Russian Federation, belonging to the institution), Z. BRENCIC, O. CHARVIAKOVA, Vratislav CHUDOBA (203 Czech Republic, belonging to the institution), Paul CONSTANTIN, M. DEHGHAN, A.S. FOMICHEV, L. V. GRIGORENKO, O. HALL, M. N. HARAKEH, J-P HUCKA, A. KANKAINEN, O. KISELEV, R. KNOEBEL, D. A. KOSTYLEVA, Sergey KRUPKO (643 Russian Federation, belonging to the institution), N. KURKOVA, N. KUZMINCHUK, I. MUKHA, Ivan MUZALEVSKII (643 Russian Federation, belonging to the institution), D. NICHITA, C. NOCIFORO, Z. PATYK, M. PFUTZNER, S. PIETRI, S. PURUSHOTHAMAN, M. P. REITER, H. ROESCH, F. SCHIRRU, Pavel SHAROV (643 Russian Federation, belonging to the institution), A. SPATARU, G. STANIC, A. STATE, Y. K. TANAKA, M. VENCELJ, M., I YAVOR and J. ZHAO

Edition

Physical Review C, 2021, 2469-9985

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10304 Nuclear physics

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

RIV identification code

RIV/47813059:19630/21:A0000164

Organization unit

Institute of physics in Opava

UT WoS

000647588600001

Keywords in English

CRYOGENIC STOPPING CELL;FRS;PERFORMANCE;PROJECTILE;SEPARATOR;SYMMETRY;SYSTEM;DECAY

Tags

Tags

International impact, Reviewed

Links

LM2018112, research and development project. LTT17003, research and development project.
Změněno: 9/3/2022 10:58, Mgr. Pavlína Jalůvková

Abstract

V originále

Mass measurements of the nuclides As-69, Se-70,Se-71, and Br-71, produced via fragmentation of a Xe-124 primary beam at the Fragment Separator (FRS) at GSI, have been performed with the multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) of the FRS Ion Catcher with an unprecedented mass resolving power of almost 1 000 000. Such high resolving power is the only way to achieve accurate results and resolve overlapping peaks of short-lived exotic nuclei, whose total number of accumulated events is always limited. For the nuclide As-69, this is the first direct mass measurement. A mass uncertainty of 22 keV was achieved with only ten events. For the nuclide Se-70, a mass uncertainty of 2.6 keV was obtained, corresponding to a relative accuracy of delta m/m = 4.0 x 10(-8), with less than 500 events. The masses of the nuclides Se-71 and Br-71 have been measured with an uncertainty of 23 and 16 keV, respectively. Our results for the nuclides Se-70,Se-71 and Br-71 are in good agreement with the 2016 Atomic Mass Evaluation, and our result for the nuclide As-69 resolves the discrepancy between the previous indirect measurements. We measured also the mass of the molecule N-14 N-15 Ar-40 (A = 69) with a relative accuracy of delta m/m = 1.7 x 10(-8), the highest yet achieved with an MR-TOF-MS. Our results show that the measured restrengthening of the proton-neutron interaction (delta V-pn) for odd-odd nuclei along the N = Z line above Z = 29 (recently extended to Z = 37) is hardly evident at the N - Z = 2 line, and not evident at the N - Z = 4 line. Nevertheless, detailed structure of delta V-pn along the N - Z = 2 and N - Z = 4 lines, confirmed by our mass measurements, may provide a hint regarding the ongoing approximate to 500 keV discrepancy in the mass value of the nuclide Br-70, which prevents including it in the world average of Ft value for superallowed 0(+) -> 0(+) beta decays. The reported work sets the stage for mass measurements with the FRS Ion Catcher of nuclei at and beyond the N = Z line in the same region of the nuclear chart, including the nuclide Br-70.