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Kunnat Sebastian

Kunnat Sebastian, Ph.D. Professor


Particle physics theory, theoretical atomic physics

Research Interest

(1) Model Independent Calculations of the angular distributions in the decay products of resonant states produced in the collisions of protons and antiprotons, as well as protons and protons in high-energy accelerators.
(2) Theoretical aspects of Quantum Cascade Lasers.
(3) Calculation of the Landau levels and the relativistic corrections to the internal energy levels of atomic ions.

Educational Background

Ph. D. (Physics),1970,  University of Maryland, College Park, MD 20742


I have been a faculty member at the University of Massachusetts Lowell, formerly known as Lowell Technological Institute, since September 1969. I received my Ph.D. in theoretical elementary particle physics from the University of Maryland.
Since then I have worked as a theorist in different areas of elementary particle physics, mostly concentrating on the phenomenology of particle physics. Since 1975 I have also worked in theoretical atomic and molecular physics, mostly concentrating on relativistic corrections to the electric dipole and magnetic dipole radiative transitions.

I have developed a very comprehensive and accurate means of calculating the relativistic corrections to the second order in v/c. I have applied my method not only to calculate the relativistic corrections in radiative transitions of atoms, but also to those of heavy quarkonia. In collaboration with my Ph.D. student John Anthony, I also calculated the relativistic corrections to the Zeeman effect in helium atoms and helium like ions. Since 1989, I also worked on the angular distribution of decay products in the proton antiproton collisions, in a completely model independent way using the relativistic helicity formalism. I have a number of papers published in this area in Physical Review, in collaboration with Prof. Howard Grotch, Fred Ridener, and Xinguo Zhang of Pennsylvania State University in University Park, Pennsylvania. I also wrote several papers in this area in collaboration with my Ph. D. student, Alex Mok. I have also published papers in the phenomenology of weak decays of hadrons in collaboration with Prof. Jogesh Pati of the University of Maryland and Dr. Tim Smith, one of my Ph. D. students.

During the summers of 2008 and 2009, I worked with Dr. Chris Baird on the theoretical aspects of Quantum Cascade Lasers, especially on the non-radiative transition rates of quantum cascade energy states, due to electron electron scattering, electron phonon scattering, scattering of electrons due to semiconductor impurities etc.

During my career here at University of Massachusetts Lowell, I have also held visiting professor positions at Indian Institute of Science in Bangalore, India, University of Rochester, Rochester, NY, University of Texas, Austin, TX, Purdue University, West Lafayette, Indiana, University of Maryland, College Park, MD, and several times at Pennsylvania State University, University Park, PA.

Here at the University of Massachusetts Lowell, I have supervised seven Ph.D. thesis students and three Master's thesis students, who have successfully completed their degrees. I have also served as the physics graduate coordinator from 1980 to 1983 and also from 2002 to 2008.                  

For details on my publications and other academic activities, please refer to my curriculum vita.