Eur. Phys. J. A (2010) 45: 251-255
https://doi.org/10.1140/epja/i2010-10998-6

Regular Article - Theoretical Physics

Prompt gamma radiation from fission fragments due to the Strutinsky-Denisov polarisation

¹ University of Buenos Aires, Viamonte 430, 1053, Buenos Aires City, Argentina
² St. Petersburg State University, 198504, Saint Petersburg, Russia

^* e-mail: fkarpeshin@ya.ru

Received: 9 March 2010
Revised: 28 May 2010
Accepted: 7 June 2010
Published online: 5 July 2010

Abstract

The hard electric dipole radiation from fission fragments of ²³⁵U by thermal neutrons is predicted. The radiation arises due to the Strutinsky-Denisov-induced polarisation mechanism. The probability of the radiation is at the level of 0.0025 per fission, which is in agreement with experiment. The angular distribution exhibits left-right asymmetry with respect to the plane perpendicular to the neutron polarisation axis. That means that the emission of gamma quanta at the given angle depends on the neutron polarisation. The asymmetry is at the level of 10^-3. This effect is similar to that observed earlier for gamma quanta in binary and alphas in ternary fission. The study of this effect will give information about dissipation of the collective energy of the surface vibration in fragments with large amplitude, and gives a picture of the process of snapping back the nuclear surface.