A1 Journal article (refereed)
Observation of an ultralow-Q-value electron-capture channel decaying to 75As via a high-precision mass measurement (2022)

Ramalho, M., Ge, Z., Eronen, T., Nesterenko, D. A., Jaatinen, J., Jokinen, A., Kankainen, A., Kostensalo, J., Kotila, J., Krivoruchenko, M. I., Suhonen, J., Tyrin, K. S., & Virtanen, V. (2022). Observation of an ultralow-Q-value electron-capture channel decaying to 75As via a high-precision mass measurement. Physical Review C, 106(1), Article 015501. https://doi.org/10.1103/PhysRevC.106.015501

JYU authors or editors

De Oliveira Ramalho, Marlom
Ge, Zhuang
Eronen, Tommi
Nesterenko, Dmitrii
Jaatinen, Jukka
Jokinen, Ari
Kankainen, Anu
Kotila, Jenni
Suhonen, Jouni
Virtanen, Ville

Publication details

All authors or editors: Ramalho, M.; Ge, Z.; Eronen, T.; Nesterenko, D. A.; Jaatinen, J.; Jokinen, A.; Kankainen, A.; Kostensalo, J.; Kotila, J.; Krivoruchenko, M. I.; et al.

Journal or series: Physical Review C

ISSN: 2469-9985

eISSN: 2469-9993

Publication year: 2022

Publication date: 05/07/2022

Volume: 106

Issue number: 1

Article number: 015501

Publisher: American Physical Society (APS)

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1103/PhysRevC.106.015501

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/82592

Abstract

A precise determination of the atomic mass of 75As has been performed utilizing the double Penning trap mass spectrometer, JYFLTRAP. The mass excess is measured to be −73035.519(42)keV/c2, which is a factor of 21 more precise and 1.3(9)keV/c2 lower than the adopted value in the newest Atomic Mass Evaluation (AME2020). This value has been used to determine the ground-state–to–ground-state electron-capture decay Q value of 75Se and β− decay Q value of 75Ge, which are derived to be 866.041(81) keV and 1178.561(65) keV, respectively. Using the nuclear energy-level data of 860.00(40) keV, 865.40(50) keV (final states of electron capture), and 1172.00(60) keV (final state of β− decay) for the excited states of 75As∗, we have determined the ground-state–to–excited-state Q values for two transitions of 75Se→75As∗ and one transition of 75Ge→75As∗. The ground-state–to–excited-state Q values are determined to be 6.04(41) keV, 0.64(51) keV, and 6.56(60) keV, respectively, thus confirming that the three low Q-value transitions are all energetically valid and one of them is a possible candidate channel for antineutrino mass determination. Furthermore, the ground-state–to–excited-state Q value of transition 75Se→75As∗ [865.40(50) keV] is revealed to be ultralow (<1 keV) and the first-ever confirmed electron capture transition possessing an ultralow Q value from direct measurements.

Keywords: nuclear physics; particle physics; neutrinos; arsenic; mass spectrometry