Flerov Laboratory of Nuclear Reactions

Joint Laboratory Seminar

Date and time: Thursday, 22 May 2025, at 3:30 PM

Venue: Conference Hall, Flerov Laboratory of Nuclear Reactions

1. Seminar topic: “Experimental study of mass and total kinetic energy distributions in reactions leading to Nobelium isotope synthesis”

   Speaker: Sanila Sathyan

   Abstract:
   

   The work aims to study the characteristics of the mass–total kinetic energy (M–TKE) distribution of binary reaction products from the ^40–48Ca + ²⁰⁸Pb reactions and to conduct a detailed examination of these reaction systems. Experiments were performed using the U400 Cyclotron at the Flerov Laboratory of Nuclear Reactions, Dubna, Russia. Binary reaction products from ⁴⁰Ca, ⁴²Ca, ⁴⁴Ca, and ⁴⁸Ca projectiles on a ²⁰⁸Pb target were detected in coincidence using the double-arm time-of-flight (ToF-ToF) spectrometer CORSET.
   
   In parallel, to explore the influence of compound nucleus angular momentum on M–TKE distributions of the ²⁵⁶No* compound nucleus, measurements were conducted for the ²⁴Mg + ²³²Th reaction at four different laboratory energies ranging from 125 MeV to 181 MeV. Both the ²⁴Mg + ²³²Th and ⁴⁸Ca + ²⁰⁸Pb reactions lead to the formation of the ²⁵⁶No* compound nucleus, allowing for a comparative analysis. In the ²⁴Mg + ²³²Th system, a detailed analysis revealed the dependence of mass variance on temperature and angular momentum, and the dependence of the variance of total kinetic energy distribution of fission fragments on angular momentum. Based on this, the contribution of non-compound nuclear fission processes in the ⁴⁸Ca + ²⁰⁸Pb reaction was estimated, along with the corresponding probability of complete fusion fission processes.

   (In connection with the election for the vacant position of a researcher.)




2. Seminar topic: “Study of heavy-ion induced collision reactions using the CORSET Spectrometer”

   Speaker: Aniruddha Dey

   Abstract:
   

   In heavy-ion induced reactions, the interaction mechanism is primarily governed by the projectile beam energy and angular momentum (L) of the composite system. Therefore, a series of experiments were performed by utilising the double-arm time-of-flight (TOF) CORSET Spectrometer at the Flerov Laboratory of Nuclear Reactions (FLNR), JINR, Russia, using energetic beams of ¹⁶O and ⁴⁸Ca delivered from the U400 Cyclotron. The thin targets of ²⁰⁸Pb and ¹⁷⁶Yb were bombarded with the ¹⁶O and ⁴⁸Ca beams, respectively at different beam energies to produce the fissioning nucleus, ²²⁴Th around the barrier, to investigstudy te the role of entrance channel angular momentum on fusion-fission and quasifission reaction mechanisms. A detailed review work on the structural details of the ^40–48Ca isotopes was carried out and will be presented during the seminar.
   
   A part of the seminar will be dedicated to the future experimental prospects with CORSET setup under the SCIF (System for Correlated Investigations of Fragments) project. Preliminary developmental works carried out to couple neutron and gamma spectrometer to obtain a comprehensive study of evaporation residues formation following heavy-ion collision reactions, will be discussed. With the similar motivation to study the underlying reaction dynamics of heavy-ion collision reactions, group’s future experimental proposal in the Indian laboratory will be discussed. The new measurement from the proposed experiment will allow to study the existence of an exotic fission mode in the lighter-Thorium isotopes, and strengthen previous understanding of the role of different shell effects on the fission process in preactinides. Furthermore, the detailed results obtained during the short-term research project based on “high resolution prompt gamma-ray spectroscopy”, under the JINR INTEREST (INTErnational REmote Student Training) programme and the speaker’s supervision will be reported during the seminar.

   (In connection with the election for the vacant position of a researcher.)