Narendra Nath Dutta

Effect of screening on spectroscopic properties of Li-like ions in a plasma environment

This work presents accurate {\it ab initio} investigations of various spectroscopic properties of a few Li-like ions in presence of a plasma environment within the Debye screening potential. The coupled-cluster theory in the relativistic framework has been employed to compute ionization potentials, excitation energies, electric dipole oscillator strengths, and electric quadrupole transition probabilities of Li-like C

ACCURATE ESTIMATIONS OF STELLAR AND INTERSTELLAR TRANSITION LINES OF TRIPLY IONIZED GERMANIUM

^{3+}

Electron-correlation study of Y iii-Tc vii ions using a relativistic coupled-cluster theory

, N

Ab initio studies of electron correlation and Gaunt interaction effects in the boron isoelectronic sequence using coupled-cluster theory

^{4+}

Ab initio calculations of spectroscopic properties of Cr5+ using coupled-cluster theory

, and O

Precise Calculations of Astrophysically Important Allowed and Forbidden Transitions of Xe viii

^{5+}

E1parity-nonconserving transition amplitudes of the hyperfine components for2S1/2−2D3/2transitions of137Ba+and87Sr+

ions. The unretarded Breit interaction has been implemented to increase the accuracy of the calculations. The effects of ion density and temperature on the ionization potentials, excitation energies, electric dipole oscillator strengths, and electric quadrupole transition probabilities have been investigated in the plasma environment. It is found that the plasma screening leads to a sharp decrease in the ionization potential as the screening strength increases. With increasing strength, the oscillator strengths associated with 2

Relativistic coupled-cluster calculations on hyperfine structures and electromagnetic transition amplitudes of In iii

s ^{2}S_{1/2}

Dynamic polarizabilities and hyperfine-structure constants forSc2+

\rightarrow2 p ^{2}P_{1/2, 3/2}