Physics Letters B (Aug 2020)
Compressional-mode resonances in the molybdenum isotopes: Emergence of softness in open-shell nuclei near A = 90
- K.B. Howard,
- U. Garg,
- M. Itoh,
- H. Akimune,
- M. Fujiwara,
- T. Furuno,
- Y.K. Gupta,
- M.N. Harakeh,
- K. Inaba,
- Y. Ishibashi,
- K. Karasudani,
- T. Kawabata,
- A. Kohda,
- Y. Matsuda,
- M. Murata,
- S. Nakamura,
- J. Okamoto,
- S. Ota,
- J. Piekarewicz,
- A. Sakaue,
- M. Şenyiğit,
- M. Tsumura,
- Y. Yang
Affiliations
- K.B. Howard
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA
- U. Garg
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA; Corresponding author.
- M. Itoh
- Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578, Japan
- H. Akimune
- Department of Physics, Konan University, Kobe 658-8501, Japan
- M. Fujiwara
- Research Center for Nuclear Physics, Osaka University, Osaka 567-0047, Japan
- T. Furuno
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan; Research Center for Nuclear Physics, Osaka University, Osaka 567-0047, Japan
- Y.K. Gupta
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA; Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- M.N. Harakeh
- KVI-CART, University of Groningen, 9747 AA Groningen, the Netherlands
- K. Inaba
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
- Y. Ishibashi
- Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578, Japan
- K. Karasudani
- Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578, Japan
- T. Kawabata
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan; Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
- A. Kohda
- Research Center for Nuclear Physics, Osaka University, Osaka 567-0047, Japan
- Y. Matsuda
- Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578, Japan
- M. Murata
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
- S. Nakamura
- Research Center for Nuclear Physics, Osaka University, Osaka 567-0047, Japan
- J. Okamoto
- Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578, Japan
- S. Ota
- Center for Nuclear Study, University of Tokyo, RIKEN Campus, Wako, Saitama 351-0198, Japan
- J. Piekarewicz
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA
- A. Sakaue
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
- M. Şenyiğit
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Physics, Faculty of Science, Ankara University, TR-06100, Tandoĝan, Ankara, Turkey
- M. Tsumura
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
- Y. Yang
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA
- Journal volume & issue
-
Vol. 807
p. 135608
Abstract
“Why are the tin isotopes soft?” has remained, for the past decade, an open problem in nuclear structure physics: models which reproduce the isoscalar giant monopole resonance (ISGMR) in the “doubly-closed shell” nuclei, 90Zr and 208Pb, overestimate the ISGMR energies of the open-shell tin and cadmium nuclei, by as much as 1 MeV. In an effort to shed some light onto this problem, we present results of detailed studies of the ISGMR in the molybdenum nuclei, with the goal of elucidating where–and how–the softness manifests itself between 90Zr and the cadmium and tin isotopes. The experiment was conducted using the 94,96,98,100Mo(α,α′) reaction at Eα=386 MeV. A comparison of the results with relativistic, self-consistent Random-Phase Approximation calculations indicates that the ISGMR response begins to show softness in the molybdenum isotopes beginning with A=92.