Swapan K. Saha
Professor, Physics

Research interests

 Observational astrophysics:  My interest in this area is to search for strangelets.  It has been shown in the literature that strangelets, which are stable lumps of Strange Quark Matter (SQM) and appears like very heavy nuclei with a very abnormal charge-to-mass ratio, could be of cosmic origin and could constitute a part of the cosmic ray flux. It has been argued that these SQM are possible candidates for dark matter, existence of which has been postulated in order to account for the observed mass of the universe. At this time we have identified and characterized a new passive detection material which we plan to use to detect these strangelets at mountain altitude.

Intermediate energy physics:  I studied the mechanism of pion production in nucleon-nucleon collisions, which is an important and unsolved problem in intermediate energy physics.  This gives us direct information about the nucleon-nucleon interaction which is still not known very well.  The experiments were carried out at the Indiana University Cyclotron Facility (IUCF) at Bloomington, USA using polarized proton on a polarized proton target in the energy range 325 to 400 MeV.  The experiments relied on the advantages offered by the use of an internal target in a storage ring. 

Group members

Dr. Supriya Das, (Research Scientist)

Dr. Sandhya Dey (Mondal) (Post-doctoral Research Associate)

Mr. Atanu Maulik (Senior Research Fellow)

 Publications in Refereed Journals (Last 10 years)

 1.       Facility for studying spin dependence of pion production near threshold, T. Rinckel, P. Thorngren-Engblom, H.O. Meyer, J.T. Balewski, J. Doscow, R.E. Pollock, B.v. Przewoski, F. Sperisen, W.W. Daehnick, R.W. Flammang, Swapan K. Saha, W. Haeberli, B. Lorentz, F. Rathmann, B. Schwartz, T. Wise, and P.V. Pancella, Nucl. Instr, Meth, A 439, 117 (2000).

 2.       Initial singlet and triplet spin state contributions to pp ® ppp⁰,  P. Thorngren-Engblom, H.O. Meyer, J.T. Balewski, W.W. Daehnick, J. Doscow, W. Haeberli, B. Lorentz, P.V. Pancella, R.E. Pollock, B.v. Przewoski, F. Rathmann, T. Rinckel, Swapan K. Saha, B. Schwartz, A. Wellinghausen, and T. Wise, Nucl. Phys. A663, 447c (2000). 

3.       Measurement of Spin Correlation Coefficients in pp ® dp⁺, B.V. Przewoski, J.T. Balewski, , J. Doscow, H.O. Meyer, R.E. Pollock, T. Rinckel, P. Thorngren-Engblom, A. Wellinghausen, W. Haeberli, B. Lorentz, F. Rathmann, B. Schwartz, T. Wise, W.W. Daehnick, Swapan K. Saha, and P.V. Pancella, Phys. Rev. C 61, 064604 (2000). 

4.       Observation of Large Longitudinal Analyzing Power in a Nuclear Reaction, H.O. Meyer, L.D. Knutson, J.T. Balewski, W.W. Daehnick, J. Doscow, W. Haeberli, B. Lorentz, P.V. Pancella, R.E. Pollock, B.V. Przewoski, F. Rathmann, T. Rinckel, Swapan K. Saha, B. Schwartz, P. Thorngren-Engblom, A. Wellinghausen, and T. Wise, Phys.Lett. B 480, 7 (2000).  

5.       Complete Set of Polarized Observables in pp ® ppp⁰ close to Threshold, H.O. Meyer, A. Wellinghausen, J.T. Balewski, J. Doscow, R.E. Pollock, B.V. Przewoski, T. Rinckel, P. Thorngren-Engblom, L.D. Knutson, W. Haeberli, B. Lorentz, F. Rathmann, B. Schwartz, T. Wise, W.W. Daehnick, Swapan K. Saha, and P.V. Pancella, Phys. Rev. C 63, 064002 (2001).  

6.       Nuclear Polarization of Hydrogen Molecules from Recombination of Polarized Atoms, T. Wise, W. Haeberli, B. Lorentz, P.A. Quinn, F. Rathmann, B. Schwartz, T.G. Walker, A. Wellinghausen, J.T. Balewski, J. Doscow, H.O. Meyer, R.E. Pollock, B.V. Przewoski, T. Rinckel, Swapan K. Saha, and P.V. Pancella, Phys. Rev. Lett. 87, 042701 (2001). 

7.       Spin correlations in pp ® pnp⁺ pion production near threshold, W.W. Daehnick, Swapan K. Saha, R.W. Flammang, H.O. Meyer, J.T. Balewski, J. Doscow, R.E. Pollock, B.V. Przewoski, T. Rinckel, P. Thorngren-Engblom, A. Wellinghausen, W. Haeberli, B. Lorentz, F. Rathmann, B. Schwartz, T. Wise, and P.V. Pancella, , Phys. Rev. C65, 024003 (2002). 

8.       Observation of Spin Exchange in Polarized Deuterium, B.V. Przewoski, H.O. Meyer, J.T. Balewski, W.W. Daehnick, J. Doscow, W. Haeberli, R. Ibald, B. Lorentz, P.V. Pancella, R.E. Pollock, F. Rathmann, T. Rinckel, Swapan K. Saha, B. Schwartz, P. Thorngren-Engblom, A. Wellinghausen, T.J. Whitaker and T. Wise, Phys. Rev. A68 042705 (2003). 

9.       Characterization of some commercial polymers for the detection of massive cosmic ray particles, B. Basu, A. Mazumdar, S. Raha, S. Saha, Swapan K. Saha, D. Syam, Ind. Jour. of Phys. 79, 279 (2005). 

10.   Analyzing powers and spin correlation coefficients for p+d elastic scattering at 135 and 200 MeV, B.V. Przewoski, H.O. Meyer, J.T. Balewski, W.W. Daehnick, J. Doscow, W. Haeberli, R. Ibald, B. Lorentz, R.E. Pollock, P.V. Pancella, F. Rathmann, T. Rinckel, Swapan K. Saha, B. Schwartz, P. Thorngren-Engblom, A. Wellinghausen, T.J. Whitaker and T. Wise, Phys. Rev. C74 064003 (2006). 

11.   Polyethylene terephthalate polymers at mountain altitude as cosmic ray heavy particle detector, B. Basu, S. Biswas, S. Dey, A. Maulik, A. Mazumdar, S. Raha, S. Saha, Swapan K. Saha, and D. Syam, Rad. Meas. 43, S262 (2008). 

12.   Charge response of polyethylene terephthalate polymers (PET) to light and heavy nuclei, B. Basu, S. Dey, B. Fischer, A. Maulik, A. Mazumdar, S. Raha, S. Saha, S.K. Saha, and D. Syam, Rad. Meas. 43, S95 (2008). 

13.   Determination of the depth of an etch pit through studies of diffraction rings, B. Basu, S. Dey, A. Maulik, S. Raha, S. Saha, Swapan K. Saha, and D. Syam, Rad. Meas. 44, 359 (2009). 

14.   A study of the g-ray flux during the total solar eclipse of 1 August 2008 at Novosibirsk, Russia, Pranaba K. Nayak, Sunil K. Gupta, Atul Jain, Indranil Mazumdar, Sibaji Raha, Swapan K. Saha, Aleksandr V. Bovrob, Anton Osipov, and Boris Schwartz, Astroparticle Physics 32, 286 (2010).

15 . Multi-pronged events from Coulomb fission of nuclei at very low energies, B. Basu, S. Dey, D. Gupta, A. Maulik, S. Raha, Swapan K. Saha, and D. Syam, Communicated to Rad. Meas. (2010) : arXiv:0812.0054v1[nucl-ex]  

16.   Observation of a rare cosmic ray event, B. Basu, S. Biswas, S. Dey, A. Maulik, A. Mazumdar, S. Raha, S. Saha, Swapan K. Saha, and D. Syam, Communicated to Physical Review Letter (2010).

 Patent

 1.       Hanging Wire Fluid Velocitimeter-cum-acoustic Pressure Gauge (Indian Patent No. 198995 (2054/CAL/97)) by Barun K. Chatterjee, Biva Roy and Swapan K. Saha. (2006)

Professional and Educational History

 ·        Education

B.Sc. (1976-1979) Presidency College, University of Calcutta, Calcutta, India

M.Sc.(1980-1982) University of Calcutta, Calcutta, India

M.S.  (1982-1983) University of Pittsburgh, Pittsburgh, USA

Ph.D (1985-1990) University of Pittsburgh, Pittsburgh, USA

 ·        Post-doctoral Research Associateship

 (1997-2000) University of Pittsburgh, Pittsburgh, USA

 ·        Visitorship

 (2001) University of Pittsburgh, Pittsburgh, USA

(2003) Indiana University Cyclotron Facility, Bloomington, USA

 ·        Faculty positions

 (1990-1993) Assistant Professor Indian Institute of Technology, Kanpur, India

(1993-1996) Lecturer, Bose Institute, Calcutta, India

(1996-2001) Senior Lecturer, Bose Institute, Calcutta, India

(2001-2006) Reader, Bose Institute, Calcutta, India

(12/06-Present) Professor, Bose Institute, Calcutta, India

 Conference, Workshops, Talks etc. (Last 10 years)

 ·         Attended the India-CERN ISOLDE Meeting at Saha Institute of Nuclear Physics, Calcutta (2009)

 ·         Participated and served as a member of Organizing Committee of the International Symposium on Millimeter Waves (ISoMM-09) at Bose Institute, Calcutta (2009)

 ·         Delivered two invited talks at Dr. Homi Bhaba Centenary Workshop and Winter School on Astroparticle Physics at Cosmic Ray Laboratory, TIFR, Ooty (2008)

 ·         Attended and delivered a talk at the All-Russian Conference on Corona and Plasma Physics at Novosibirsk State University, Novosibirsk, Russia (2008)

 ·         Served as joint-coordinator for the North East Student’s Training Program (NESST-BASE) organized by Bose Institute at Darjeeling (2008)

 ·         Attended and presented a poster at the Quark Matter 2008, 20^th International Conference on Ultra-relativistic Nucleus-Nucleus Collisions at Jaipur (2008)

 ·         Organized the 2^nd Workshop and a School on Astroparticle Physics WAPP-07 at Bose Institute, Darjeeling (2007)

 ·         Served as a member of the Organizing Committee of the North East Student’s Training Program (NESST-BASE) organized by Bose Institute at Darjeeling (2007) 

·         Delivered a talk at the ISRO-Respond Review Meeting at the Physical Research Laboratory, Ahmedabad (2007)

 ·         Participated and served as a member of Organizing Committee of the 21^st Int. Workshop on Weak Interactions and Neutrinos at Saha Institute of Nuclear Physics, Calcutta (2007)

 ·         Delivered two invited talks at Golden Jubilee Workshop on Astroparticle Physics at Cosmic Ray Laboratory, TIFR, Ooty (2006)

 ·         Delivered two talks at the 23^rd International Conference of Nuclear Track Society at Beijing, China (2006)

 ·         Delivered a talk at the DAE-DST Vision Meeting for Drawing Roadmap for High Energy & Nuclear Physics Research at Homi Bhabha Centre for Science Education, TIFR, Mumbai (2006)

 ·         Attended the 1^st Workshop on Astroparticle Physics & Space Science to deliver a talk at Bose Institute, Darjeeling (2005).

 ·         Attended the 29^th International Cosmic Ray Conference to deliver a talk at Pune (2005).

 ·         Attended the 21^st International Conference on Nuclear Tracks in Solids to present a poster in New Delhi (2002).

 ·         Attended the Meeting of the American Physical Society to deliver a talk at Long Beach, California (2000).