Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction

K. Nishio; K. Hirose; H. Makii; R. Orlandi; K. R. Kean; K. Tsukada; A. Toyoshima; M. Asai; T. K. Sato; N. M. Chiera; T. Tomitsuka; K. Tokoi; R. Yanagihara; H. Suzuki; Y. Nagame; K. Okada; A. N. Andreyev; T. Tanaka; K. Morimoto; S. Ishizaki; M. Okubayashi; Y. Miyamoto; S. Tanaka; S. Takagi; Y. Aritomo; S. Kubono; N. Iwasa; M. Egeta; S. Sakaguchi; S. Matsunaga; Y. Ishibashi; K. P. Rykaczewski; R. A. Boll; J. G. Ezold; L. K. Felker; J. B. Roberto

doi:10.1103/PhysRevC.111.044609

Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction

K. Nishio
, K. Hirose
, H. Makii
, R. Orlandi
, K. R. Kean
, K. Tsukada
, A. Toyoshima
, M. Asai
, T. K. Sato
, N. M. Chiera
, T. Tomitsuka
, K. Tokoi
, R. Yanagihara
, H. Suzuki
, Y. Nagame
, K. Okada
, A. N. Andreyev
, T. Tanaka
, K. Morimoto
, S. Ishizaki

M. Okubayashi, Y. Miyamoto, S. Tanaka, S. Takagi, Y. Aritomo, S. Kubono, N. Iwasa, M. Egeta, S. Sakaguchi, S. Matsunaga, Y. Ishibashi, K. P. Rykaczewski, R. A. Boll, J. G. Ezold, L. K. Felker, J. B. Roberto

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

Earlier studies of spontaneous fission of heavy actinides found that the fission-fragment mass distribution suddenly changes from predominantly asymmetric to symmetric, when the mass number of the fissioning nucleus becomes larger than Ac=257. We have measured for the first time fission-fragment mass and total-kinetic-energy (TKE) distributions of the excited compound nucleus Md∗258 (Z=101), populated in the reaction He4+Es254, using the rare radioactive target isotope Es254 with a short half-life, T1/2=275.7d. The fission of Md∗258 can be interpreted as involving three fission modes: one mass-asymmetric and two mass-symmetric fission modes, the latter two are manifested by different TKE values. In this assumption, symmetric and asymmetric fission modes have nearly similar yields at the excitation energy of 15.0 MeV. The spectrum of 18.0 MeV can be explained as due to the increase of asymmetric fission mode.

Original language	English
Article number	044609
Journal	Physical Review C
Volume	111
Issue number	4
DOIs	https://doi.org/10.1103/PhysRevC.111.044609
State	Published - Apr 2025

Funding

We thank the crew of the JAEA tandem accelerator facility for supplying a high-quality stable beam. Special thanks for calculating FFMDs are due to Dr. P. Möller and Prof. I. Tsekhanovich. A.A. was partially supported by a STFC UK grant. This research was also supported by the Office of Nuclear Physics, U.S. Department of Energy (U.S. DOE), under Contract No. DE-AC05-00OR22725 and by the U.S. DOE Isotope Program. The six-dimensional Langevin calculation was performed with the JAEA supercomputer HPE SGI8600.

Access to Document

10.1103/PhysRevC.111.044609

Cite this

Nishio, K., Hirose, K., Makii, H., Orlandi, R., Kean, K. R., Tsukada, K., Toyoshima, A., Asai, M., Sato, T. K., Chiera, N. M., Tomitsuka, T., Tokoi, K., Yanagihara, R., Suzuki, H., Nagame, Y., Okada, K., Andreyev, A. N., Tanaka, T., Morimoto, K., ... Roberto, J. B. (2025). Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction. Physical Review C, 111(4), Article 044609. https://doi.org/10.1103/PhysRevC.111.044609

@article{82806d784bb8439d81d202b7f66050f1,

title = "Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction",

abstract = "Earlier studies of spontaneous fission of heavy actinides found that the fission-fragment mass distribution suddenly changes from predominantly asymmetric to symmetric, when the mass number of the fissioning nucleus becomes larger than Ac=257. We have measured for the first time fission-fragment mass and total-kinetic-energy (TKE) distributions of the excited compound nucleus Md∗258 (Z=101), populated in the reaction He4+Es254, using the rare radioactive target isotope Es254 with a short half-life, T1/2=275.7d. The fission of Md∗258 can be interpreted as involving three fission modes: one mass-asymmetric and two mass-symmetric fission modes, the latter two are manifested by different TKE values. In this assumption, symmetric and asymmetric fission modes have nearly similar yields at the excitation energy of 15.0 MeV. The spectrum of 18.0 MeV can be explained as due to the increase of asymmetric fission mode.",

author = "K. Nishio and K. Hirose and H. Makii and R. Orlandi and Kean, \{K. R.\} and K. Tsukada and A. Toyoshima and M. Asai and Sato, \{T. K.\} and Chiera, \{N. M.\} and T. Tomitsuka and K. Tokoi and R. Yanagihara and H. Suzuki and Y. Nagame and K. Okada and Andreyev, \{A. N.\} and T. Tanaka and K. Morimoto and S. Ishizaki and M. Okubayashi and Y. Miyamoto and S. Tanaka and S. Takagi and Y. Aritomo and S. Kubono and N. Iwasa and M. Egeta and S. Sakaguchi and S. Matsunaga and Y. Ishibashi and Rykaczewski, \{K. P.\} and Boll, \{R. A.\} and Ezold, \{J. G.\} and Felker, \{L. K.\} and Roberto, \{J. B.\}",

note = "Publisher Copyright: {\textcopyright} 2025 American Physical Society.",

year = "2025",

month = apr,

doi = "10.1103/PhysRevC.111.044609",

language = "English",

volume = "111",

journal = "Physical Review C",

issn = "2469-9985",

publisher = "American Physical Society",

number = "4",

}

Nishio, K, Hirose, K, Makii, H, Orlandi, R, Kean, KR, Tsukada, K, Toyoshima, A, Asai, M, Sato, TK, Chiera, NM, Tomitsuka, T, Tokoi, K, Yanagihara, R, Suzuki, H, Nagame, Y, Okada, K, Andreyev, AN, Tanaka, T, Morimoto, K, Ishizaki, S, Okubayashi, M, Miyamoto, Y, Tanaka, S, Takagi, S, Aritomo, Y, Kubono, S, Iwasa, N, Egeta, M, Sakaguchi, S, Matsunaga, S, Ishibashi, Y, Rykaczewski, KP, Boll, RA, Ezold, JG, Felker, LK & Roberto, JB 2025, 'Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction', Physical Review C, vol. 111, no. 4, 044609. https://doi.org/10.1103/PhysRevC.111.044609

TY - JOUR

T1 - Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction

AU - Nishio, K.

AU - Hirose, K.

AU - Makii, H.

AU - Orlandi, R.

AU - Kean, K. R.

AU - Tsukada, K.

AU - Toyoshima, A.

AU - Asai, M.

AU - Sato, T. K.

AU - Chiera, N. M.

AU - Tomitsuka, T.

AU - Tokoi, K.

AU - Yanagihara, R.

AU - Suzuki, H.

AU - Nagame, Y.

AU - Okada, K.

AU - Andreyev, A. N.

AU - Tanaka, T.

AU - Morimoto, K.

AU - Ishizaki, S.

AU - Okubayashi, M.

AU - Miyamoto, Y.

AU - Tanaka, S.

AU - Takagi, S.

AU - Aritomo, Y.

AU - Kubono, S.

AU - Iwasa, N.

AU - Egeta, M.

AU - Sakaguchi, S.

AU - Matsunaga, S.

AU - Ishibashi, Y.

AU - Rykaczewski, K. P.

AU - Boll, R. A.

AU - Ezold, J. G.

AU - Felker, L. K.

AU - Roberto, J. B.

PY - 2025/4

Y1 - 2025/4

N2 - Earlier studies of spontaneous fission of heavy actinides found that the fission-fragment mass distribution suddenly changes from predominantly asymmetric to symmetric, when the mass number of the fissioning nucleus becomes larger than Ac=257. We have measured for the first time fission-fragment mass and total-kinetic-energy (TKE) distributions of the excited compound nucleus Md∗258 (Z=101), populated in the reaction He4+Es254, using the rare radioactive target isotope Es254 with a short half-life, T1/2=275.7d. The fission of Md∗258 can be interpreted as involving three fission modes: one mass-asymmetric and two mass-symmetric fission modes, the latter two are manifested by different TKE values. In this assumption, symmetric and asymmetric fission modes have nearly similar yields at the excitation energy of 15.0 MeV. The spectrum of 18.0 MeV can be explained as due to the increase of asymmetric fission mode.

AB - Earlier studies of spontaneous fission of heavy actinides found that the fission-fragment mass distribution suddenly changes from predominantly asymmetric to symmetric, when the mass number of the fissioning nucleus becomes larger than Ac=257. We have measured for the first time fission-fragment mass and total-kinetic-energy (TKE) distributions of the excited compound nucleus Md∗258 (Z=101), populated in the reaction He4+Es254, using the rare radioactive target isotope Es254 with a short half-life, T1/2=275.7d. The fission of Md∗258 can be interpreted as involving three fission modes: one mass-asymmetric and two mass-symmetric fission modes, the latter two are manifested by different TKE values. In this assumption, symmetric and asymmetric fission modes have nearly similar yields at the excitation energy of 15.0 MeV. The spectrum of 18.0 MeV can be explained as due to the increase of asymmetric fission mode.

UR - https://www.scopus.com/pages/publications/105003674981

U2 - 10.1103/PhysRevC.111.044609

DO - 10.1103/PhysRevC.111.044609

M3 - Article

AN - SCOPUS:105003674981

SN - 2469-9985

VL - 111

JO - Physical Review C

JF - Physical Review C

IS - 4

M1 - 044609

ER -

Competition between mass-symmetric and asymmetric fission modes in Md 258 produced in the He 4 + Es 254 reaction

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this