Dr. Rajesh Srivastava
Ph. D. (Banaras Hindu University, Varanasi)
PROFESSOR
Dr. Rajesh Srivastava is a theoretical Physicist. He works on a wide variety of problems in Atomic and Molecular Collision Physics. Dr. Srivastava obtained his Doctoral Degree from Banaras Hindu University in 1978 for his thesis work on “Electron – Atom Scattering Theory”. He was then Postdoctoral Fellow at FOM Institute of Atomic and Molecular Physics, Amsterdam, Netherlands during the period 1978 - 80. Thereafter, he was a Lecturer in the Physics Department, Banaras Hindu University up to 1983. Then he joined the Faculty of the Department of Physics, I.I.T. Roorkee (formerly University of Roorkee) where he is now a full Professor.
He is life member of the Indian Society of Atomic and Molecular Physics (ISAMP) and presently he is Vice –President of this society. He has been member of various International Scientific Advisory Committees including ICPEAC. He is recipient of “UGC Career Award in Physics” for the year 1994. He was selected for the Senior Common Wealth Fellowship Award in 1991 from Canada and Senior JSPS Fellowship Award from Japan in 2002. He has been invited to deliver talks and to Chair the sessions in various International Conferences abroad. He is also referee to various journals viz. Physical Review, Physical Review Letters, Journal of Physics B and European Journal of Physics etc.
He has been Visiting Professor/Fellow to various institutions abroad viz. Holland, USA, UK, Australia, Japan, Canada and Germany. He published over 140 research papers in refereed Journals and books, attended National (20) and International Conferences abroad (17) and presented nearly 120 research papers. His research collaborations have been with various theoretical and experimental groups world wide.
An outline of the work carried out
by
Dr. Rajesh Srivastava and his group
There is great demand of reliable calculations in the area of Atomic and Molecular Collision Physics brought out by their large scale applications in different field of science. The research interest in this area has been in developing theoretical formulations and performing extensive numerical computations for various collision processes dealing electrons, positrons and different charged particles impacting on neutral atoms and ions. Involving the Ph. D. students and other theoretical and experimental collaborators from abroad, the group has studied several processes quantum mechanically viz. elastic and inelastic scattering of electrons and positrons from lighter and heavier atomic targets.
Ø Reliable distorted wave (DW) approximation methods have been developed and used to describe various collision processes. The lighter atomic targets are represented through Hartree-Fock wave functions while heavier atoms are described through Dirac-Fock wave functions. The continuum non-relativistic and relativistic distorted waves (RDW) are obtained by solving respectively the Schrödinger and Dirac equations. In case of excitation of atomic systems the usual scattering cross sections as well as the spin polarization parameters for scattered electrons are calculated using density matrix theory. Stokes parameters for the light emitted through decay of atoms after excitations are also studied in extensive manner. Processes are studied in the light of “complete” experiment.
Ø The group has now extended the formulations of the relativistic distorted wave calculations to study the excitation from the initially excited (metastable states) of the atoms. This RDW method is being applied to explore its suitability to study various such excitations in alkaline earth atoms and inert gases.
Ø Currently, the group is studying the (e, 2e) processes and electron excitation of Auger states and their decay in heavier atomic targets by using relativistic distorted wave theory.
Ø There are also efforts to extend the fully relativistic formulations to study the electron impact excitations of various heavier ions.
The research work of the group has been financially supported through various sponsored research projects from AOARD Japan, US Agencies, CSIR, DST, DAE-BRNS and UGC.
Selected recent publications
Ø (e, eγ)-coincidence studies to determine spin-resolved Stokes parameters of the 185 nm emission line in mercury, (G Außendorf, F Jüttemann, K Muktavat, L Sharma, R Srivastava, A D Stauffer, K Bartschat, D V Fursa, I Bray and G F Hanne), J. Phys. B: At. Mol. Opt. Phys. 39 (2006) 2403.
Ø Coplanar doubly symmetric (e,2e) process on sodium and potassium, (M. K. Srivastava, Raj Kumar Chauhan and R. Srivastava), Phys. Rev. A, 74 (2006) 064701.
Ø Study of electron impact excitation of atoms through lasers, (R Srivastava and S Saxena), Radiation Physics and Chemistry, 75 (2006) 2136.
Ø Electron scattering by magnesium: excitation of the 3s3p 1P1 state,
(D M Filipovic, B Predojevic, V Pejcev, D Sevic, B P Marinkovic, Rajesh Srivastava and A D Stauffer), J. Phys. B: At. Mol. Opt. Phys. 39 (2006) 2583.
Ø Excitation of the metastable states of the noble gases, (R. Srivastava, A. D. Stauffer and Lalita Sharma), Phys. Rev. A 74 (2006) 012715.
Ø Triple differential cross-section for the ionization of H− at low energies, (R. K. Chauhan, M. K. Srivasatava and R. Srivastava), Eur. Phys. J. D, 35, (2005) 499.
Ø Inelastic electron scattering from excited barium atoms, (R. Srivastava and A. D. Stauffer), Phys. Rev. A 71, (2005) 052715.
Ø Electron impact excitation of the 31P state of Mg-like ions: S4+, Ar6+ and Ca8+ (K. Takeshi, R. Srivastava and S. Nakazaki), Phys. Rev. A 70 (2004) 062705.
Ø Triple differential cross sections of coplanar (e, 2e) process on helium-like ions (R. K. Chauhan, M. K. Srivastava and R. Srivastava), Ind. J. Phys. 78 (2004) 1073
Ø Electron-impact excitation of Si2+: differential cross sections and Stokes parameters (K. Takeshi, R. Srivastava and S. Nakazaki), J. Phys. B 37 (2004) 2045.
Ø Electron impact excitation of the argon 3p54s configuration: differential cross-sections and cross-section ratios (M. A. Khakoo, P. V. Vandeventer, J. G. Childers, I. Kanik, C. J. Fontes, K. Bartschat, V. Zeman, D. H. Madison, S. Saxena, R Srivastava and A. D. Stauffer), J. Phys. B 37 (2004) 247.
Ø Electron impact coherence parameters for the excitation of the 61S0–61P1 transition in barium (K. Muktavat, R. Srivastava and A. D. Stauffer), J. Phys. B 37 (2004) 2165.
Ø Electron impact excitation of the argon 3p54s configuration: Differential cross sections and cross-section ratios ( M A Khakoo, P Vandeventer, J G Childers, I Kanik, C J Fontes, K Bartschat, V Zeman, D H Madison, S Saxena, R Srivastava and A D Stauffer), J. Phys. B 36 (2003) 247.
Ø Complete description of the excitation of the 63P1 and 61P1 states of mercury by spin polarized electrons (K. Muktavat, R. Srivastava and A. D. Stauffer), J. Phys. B 36 (2003) 2356.
Ø Electron excitation of the 1,3D states of calcium and strontium (K. Muktavat, R. Srivastava and A. D. Stauffer), J. Phys. B 35 (2002) 4797.
Ø Orientation propensities in spin-resolved electron-impact excitation of Mercury (C. Herting, G. F. Hanne, K. Bartschat, A. N. Grum-Grzhimailo, K. Muktavat, R. Srivastava and A. D. Stauffer), J. Phys. B 35 (2002) 4439.
Ø Electron-photon polarization correlation study of the 51P1 state of Cd atoms excited by electron impact (M. Piwinski, D. Dziczek, R. Srivastava, M. Gradziel and S. Chwirot), J. Phys. B 35 (2002) 3821.
Ø Electron excitation of the group IV elements (R. Srivastava, R. P. McEachran and A.D. Stauffer), Can. J. Phys. 80 (2002) 687.
Ø Excitation of thallium and lead atoms by electrons in the Relativistic Distorted Wave Approximation(S. Kaur, R. Srivastava, R. P. McEachran and A.D. Stauffer) J. Phys. B 33 (2000) 2539.
Ø Excitation of the D states of Magnesium (R. P. McEachran and A. D. Stauffer) J. Phys. B 34 (2001) 2071.
Ø Excitation of autoionizing np5(n+ 1 )s2, 2P3/2,1/2 states of Na(n=2), K(n=3), Rb(n=4) and Cs(n=5) by electron impact (Savinder Kaur and R. Srivastava) J. Phys. B 32 (1999) 2323.
Ø Stokes parameters and differential cross section for electron impact excitation of the 2p53p J= 1, 2 and 3 states of neon (S. Kaur, R. Srivastava, R. P. McEachran and A.D. Stauffer) J. Phys. B 31 (1998) 157.
Ø Differential cross sections and angular correlation in electron excitation of the 3D states of atomic hydrogen (S.Verma and R. Srivastava) J. Phys. B 30 (1997) 1393.
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