2018 Impact factor 2.481
Hadrons and Nuclei
Eur. Phys. J. A 4, 343-348

Fragment dependence of high energy $\gamma$-ray emission in the spontaneous fission of 252Cf

D.C. Biswas1 - B.K. Nayak1 - M. Cinausero2 - B. Fornal3 - G. Viesti4 - D. Bazzacco4 - M. DePoli2 - D. Fabris4 - E. Fioretto2 - M. Lunardon4 - D.R. Napoli2 - G. Nebbia4 - G. Prete2 - C.A. Ur4 - G. Vedovato2

1 Bhabha Atomic Research Centre, Mumbai, India
2 I.N.F.N., Laboratori Nazionali di Legnaro, Via Romea, 4, I-35020 Legnaro, Italy
3 Institute of Nuclear Physics, Krakow, Poland
4 Dipartimento di Fisica and INFN, Sezione di Padova, Padova, Italy

Received: 22 December 1998 Communicated by D. Schwalm

Abstract
The high energy $\gamma$-ray emission accompanying the spontaneous fission of 252Cf has been measured in coincidence with individual fission fragments selected by discrete $\gamma$-ray transitions. The enhancement of the $\gamma$-ray emission probability in the energy range E$_{\gamma}$=3-8 MeV has been observed for the fission fragments in the region of nearly symmetric mass splitting, confirming results reported in previous investigations. The $\gamma$-$\gamma$ coincidence technique employed in the present work clearly demonstrate that the major contribution to this enhancement is caused by the fission channels where one fragment is near to the N=82 or Z=50 shell closures. The high energy $\gamma$-ray emission probability does not show any significant dependence on the number of neutrons emitted in the fission process, supporting the hypothesis that high energy $\gamma$-rays are mainly emitted from the fragments after the neutron evaporation.

PACS
25.85.Ca Spontaneous fission - 23.20.Lv Gamma transitions and level energies - 27.60.+j
$90 \le A \le 149$


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