Mathematical and Physical Sciences
Research Interests: Atomic molecular and plasma physics, Trap electron, positron and ion beam physics.
Profile
Soumen Ghosh is an Assistant Professor in the Mathematical and Physical Sciences division of the School of Arts and Sciences. He obtained his MSc in Physics from the University of Calcutta, and his PhD from the Institute for Plasma Research, Gandhinagar. During his doctoral studies he identified the cause of localised electron heating observed in radio-frequency-driven expanding helicon plasma.
After brief postdoctoral research work on fusion-like tokamak plasma experiments at the Institute for Plasma Research, Professor Ghosh moved to the University of California San Diego for postdoctoral research. There, he worked with a state-of-the-art, trap-based positron beam, which is around six times colder than even room temperature and used it for studies of resonant positron-molecule interactions and the study of positron-molecule bound states. A new resonant interaction with molecular vibrational modes beyond the fundamentals was identified. This mechanism is relevant to understanding enhanced positron annihilation in large molecules, both laboratory environments and, potentially, from the interstellar medium.
In addition to research in physics, Professor Ghosh enjoys teaching the subject to students. At the School of Arts and Sciences, he is teaching core physics courses to undergraduate students majoring in physics and engineering.
Professor Ghosh received the Parvez Guzdar Young Scientist Award - 2020 for his research contributions to helicon wave plasma studies and slow positron beam physics.
Research
Professor Ghosh works on broad range of experimental physics topics, including charged particle interactions (positrons, electrons, ions, beams etc) with atoms and molecules, plasma physics, antimatter-matter interactions, and applied physics.
Selected Publications
- S. Ghosh, J. R. Danielson, and C. M. Surko, Resonant Annihilation and Positron Bound States in Benzene, Phys. Rev. Lett., 129, 123401 (2022).
- S. Ghosh, J. R. Danielson, and C. M. Surko, Enhanced resonant positron annihilation due to non-fundamental modes in molecules, Phys. Rev. Lett., 125, 173401 (2020).
- S. Ghosh, J. R. Danielson, and C. M. Surko, Energy distribution and adiabatic guiding of a soild-neon-moderated positron beam, J. Phys. B: At. Mol. Opt. Phys., 53, 085701 (2020).
- S. Ghosh, S. Yadav, K. K. Barada, P. K. Chattopadhyay, J. Ghosh, R. Pal and D. Bora, Formation of annular plasma downstream by magnetic aperture in the Helicon Experimental (HeX) device, Phys. Plasma (Letter), 24, 020703 (2017).
- S. Ghosh, P. K. Chattopadhyay, J. Ghosh, R. Pal and D. Bora, Transition from single to multiple axial potential structures (MAPS) in expanding helicon plasma, J. Phys. D: Appl. Phys., 50, 065201 (2017).
- S. Ghosh, K. K. Barada, P. K. Chattopadhyay, J. Ghosh, and D. Bora, Localized electron heating and density peaking in downstream helicon plasma, Plasma Sources Sci. Technol., 24, 034011 (2015).
Teaching
- PHY 111: Classical Mechanics
- PHY 212: Oscillations, Waves and Optics
- PHY 321: Laboratory Physics - Electronics
- PHY 635: Introduction to Plasma Physics (PhD level elective course)
- FDP 102: Foundation Programme - Environment and Climate Change
Awards
- The Parvez Guzdar Young Scientist Award - 2020, Plasma Science Society of India (PSSI).
Research Grants
-
Ahmedabad University Research Board Startup Grant: 2023-2026
PI: Soumen Ghosh
Project title: Study of ion beam energy generated by the double layers in expanding radio-frequency plasma
-
SERB Startup Research Grant: 2024-2026
PI: Soumen Ghosh
Project title: Study of electron energy distribution on formation of double layer in expanding plasma
Opportunities
I am setting up Plasma Physics Research Laboratory (PPRL) at the Ahmedabad University.
PhD positions: If you are interested to be a part of this journey (developing a laboratory from an empty room) to study some of the fundamental physics problems related to electron and ion energy distributions in expanding plasmas, feel free to write to us for PhD positions. Whether you have taken a plasma physics course or not is not that essential, a MSc in physics or applied physics with interest in experimental research is expected.
Postdoctoral positions: If you are interested in any of our projects or wish to collaborate on a project, write to us. We can help in getting extramural funds from national/international agencies to support the proposal.
Our group is accepting applications from Ahmedabad University students for
- BS thesis (Major in Physics)
- Under-Graduate Research Project (Open for all disciplines!)
Our group is also accepting applications from other College and University students for summer research projects.
Physics Outreach
- Why does antimatter matter?
A talk followed by interaction session with high school students, Smt. Sulochanadevi Singhania School, Thane, Mumbai, India, December 19, 2022.