B. Dasmahapatra

Bio: B. Dasmahapatra is an academic researcher from Saha Institute of Nuclear Physics. The author has contributed to research in topics: Coulomb barrier & Radioactive decay. The author has an hindex of 10, co-authored 35 publications receiving 305 citations.

Characterisation of a Compton suppressed Clover detector for high energy gamma rays (⩽11MeV)

Abstract: Gamma ray spectra of two (p,γ) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5 MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11 MeV.

Observation of magnetic rotation in odd-odd Ag-104

Abstract: The high spin level structure of $^{104}\text{Ag}$ has been extended to ${I}^{\ensuremath{\pi}}={20}^{+}$ and excitation energy of $7.159\phantom{\rule{0.3em}{0ex}}\text{MeV}$ through the discrete line $\ensuremath{\gamma}$-ray spectroscopy. The negative parity ground state band has been confirmed and extended to ${I}^{\ensuremath{\pi}}={18}^{\ensuremath{-}}$. Two new nonyrast dipole bands, one with positive and the other with negative parity, have been observed. The parities of the two bands have been established through polarization directional correlation measurement of the feed-out transitions from these bands. The level lifetimes have been measured in the ground state band and the positive parity dipole band. The measured total angular momenta and the $B(M1)$ rates have been compared with the predictions of hybrid version of the tilted axis cranking. The $B(M1)$ rates have also been compared with the values obtained from D\"onau's geometric formula. The tilted axis calculations give good overall agreement which suggests that all the three bands of $^{104}\text{Ag}$ exhibits magnetic rotation.

Shape coexistence in atomic nuclei

Abstract: Shape coexistence in nuclei appears to be unique in the realm of finite many-body quantum systems It differs from the various geometrical arrangements that sometimes occur in a molecule in that in a molecule the various arrangements are of the widely separated atomic nuclei In nuclei the various ''arrangements'' of nucleons involve (sets of) energy eigenstates with different electric quadrupole properties such as moments and transition rates, and different distributions of proton pairs and neutron pairs with respect to their Fermi energies Sometimes two such structures will ''invert'' as a function of the nucleon number, resulting in a sudden and dramatic change in ground-state properties in neighboring isotopes and isotones In the first part of this review the theoretical status of coexistence in nuclei is summarized Two approaches, namely, microscopic shell-model descriptions and mean-field descriptions, are emphasized The second part of this review presents systematic data, for both even- and odd-mass nuclei, selected to illustrate the various ways in which coexistence is observed in nuclei The last part of this review looks to future developments and the issue of the universality of coexistence in nuclei Surprises continue to be discovered With the major advances in reaching to extremes of proton-neutronmore » number, and the anticipated new ''rare isotope beam'' facilities, guidelines for search and discovery are discussed« less