• Heavy-Ion Nuclear Reactions

• Nuclear Instrumentation

• Nuclear reactions of Astrophysical Importance

• Solar energy storage with solar ponds

• N. W. K. Jayatissa, P. S. Hewageegana, P. A. A. Perera, M. A. Punyasena, Optimization of Thermal Insulation of a Small-scale Experimental Solar Pond, Sri Lanka J. of Phys. 13, 49-57 (2012).

• Z Elekes, Zs Dombrádi, N Aoi, S Bishop, Zs Fülöp, J Gibelin, T Gomi, Y Hashimoto, N Imai, N Iwasa, H Iwasaki, G Kalinka, Y Kondo, AA Korsheninnikov, K Kurita, M Kurokawa, N Matsui, T Motobayashi, T Nakamura, T Nakao, E Yu Nikolskii, TK Ohnishi, T Okumura, S Ota, PAA Perera, A Saito, H Sakurai, Y Satou, D Sohler, Search for neutron decoupling in 22O via the (d,d' gamma) reaction,Physical Review C Nuclear Physics 74, pp. 7306 (2006)

• Z Elekes, Zs Dombrádi, S Bishop, Zs Fülöp, J Gibelin, T Gomi, Y Hashimoto, N Imai, N Iwasa, H Iwasaki, G Kalinka, Y Kondo, AA Korsheninnikov, K Kurita, M Kurokawa, N Matsui, T Motobayashi, T Nakamura, T Nakao, E Yu Nikolskii, TK Ohnishi, T Okumura, S Ota, PAA Perera, A Saito, H Sakurai, Y Satou, D Sohler, T Sumikama,Testing of the RIKEN-ATOMKI CsI(Tl) array in the study of 22,23O nuclear structure, European Physical Journal A direct (e) Supplement 27, pp. 321 (2006)

• MA Punyasena, CD Amarasekara, JRP Jayakody, PAA Perera, P Ehamparam, An Investigation of Rain and Wind Effects on Thermal Stability of Large-Area Saltpan Solar Ponds. Solar Energy 74, pp. 447-451 (2003)

• JRP Jayakody, PAA Perera, MA Punyasena, CD Amarasekara, MAS Kumarasinghe,Construction of a Large Area solar Pond for the Harnessing of Solar Energy,Proc. Annual Research Symp. 2002, University of Kelaniya (2002)

• PAA Perera , CD Amarasekara, JRP Jayakody, MA Punyasena, Daytime Variation of Temperature and Salinity Profiles in Large-Area Saltpan Solar Ponds at Palavi, Sri Lanka, Proc. 18th Tech. Sess. Inst. Phys., Sri Lanka (2002)

• MA Punyasena, CD Amarasekara, JRP Jayakody, PAA Perera, A Study of Wind Effects on Thermal Stability of Salt Pan Solar Ponds,Proc. Annual Research Symp. 2001, University of Kelaniya (2001)

• PAA Perera, CD Amarasekara, JRP Jayakody, MA Punyasena, A Study of Daytime Variation of Convective and Non-Convective Zones in Salt Pan Solar Ponds,Proc. Annual Research Symp. 2001, University of Kelaniya (2001)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, A Young and JE Yurkon, Positron - Electron Pairs Produced in Heavy-Ion Collisions. Phys. Rev. C6006, pp. 4601(1999)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, A Young and JE Yurkon, The Positron-Electron Peak Puzzle - Results from APEX. Z. Phys. A358, pp. 235 (1997)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, A Young and JE Yurkon, Search for Monoenergetic Positron Emission from Heavy-Ion Collisions at Coulomb-Barrier Energies. Phys. Rev. Lett. 78, pp. 618 (1997)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JS Greenberg, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, A Young and JE Yurkon, Internal Pair Conversion in Heavy-Nuclei. Phys. Rev. C55, pp. R2755 (1997)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JP Greene, JS Greenberg, AL Hallin, Th Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, AR Young and JE Yurkon, APEX and the e+/e- Puzzle: Recent Results, Proc. 12th Winter Wkshp on Nuclear Dynamics, Snowbird (1996)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JS Greenberg, JP Greene, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, A Young and JE Yurkon, A Solenoidal Spectrometer for Positron-Electron Pairs Produced in Heavy-Ion Collisions. Nucl. Instrum. Methods A370, 539 (1996)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, T Happ, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, A Young and JE Yurkon, The Positron Peak Puzzle - Recent Results from APEX. Acta Physica Polonica B27, pp. 387 (1995)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, Th Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, AR Young and JE Yurkon, A New Look at Positron Production from Heavy-Ion Collisions: Results from APEX. Proc. Weak and Electromagnetic Interactions in Nuclei' 95 Conference, Osaka (1995), ed. by H Ejiri, T Kishimoto and T Sato (World Scientific, Singapore) pp. 629 (1995)

• I Ahmad, SM Austin, BB Back, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, C Conner, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, AL Hallin, T Happ, D Henderson, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, A Young and JE Yurkon, Search for Narrow Sum-Energy Lines in Electron-Positron Pair Emission from Heavy-Ion Collisions near the Coulomb Barrier. Phys. Rev. Lett. 75, pp.2658 (1995)

• DM Herrick, FLH Wolfs, DC Bryan, CG Freeman, KL Kurz, DH Mathews, PAA Perera and MT Zanni, Elastic-Scattering and Quasi-Elastic Transfer for S-32 + Mo-96, Mo-100 at E(Lab) = 180 MeV. Phys. Rev. C52, pp. 744 (1995)

• I Ahmad, SM Austin, BB Back, D Bazin, RR Betts, FP Calaprice, KC Chan, AA Chishti, P Chowdhury, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JS Greenberg, SB Gazes, AL Hallin, T Happ, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, A Young and JE Yurkon, Positron Production in Heavy-Ion Collisions - Current Status of the Problem, Nuclear Physics A583, pp. c247 (1995)

• CG Freeman, DM Herrick, DC Bryan, KL Kurz, DH Mathews, PAA Perera, FLH Wolfs and MT Zanni, New Focal Plane Detector System for the Rochester Recoil Mass Spectrometer,Nucl. Instrum. Methods A357, pp. 450 (1995)

• PAA Perera, A Search for Peak Structures in the Positron-Electron Sum-Energy Spectra for the238U + 181Ta System at 6.3, 6.1 and 5.95 MeV/u s, PhD Thesis, Department of Physics, University of Rochester, USA (1995)

• I Ahmad, SM Austin, BB Back, D Bazin, RR Betts, FP Calaprice, KC Chan, AA Chishti, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JS Greenberg, AL Hallin, Th Happ, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, AR Young, G Xu and JE Yurkon, Recent Results from APEX, Proc. Conference on Physics from Large Gamma-ray Detector Arrays, Berkeley, pp. 125 (1994)

• PR Wilt, RR Betts, M Freer, Th Happ, MR Maier, PAA Perera, MD Rhein, M Robertson, D Sowinski, FLH Wolfs and AH Wuosmaa, Electronics for the Si Detectors in APEX,Proceedings of the Fourth Annual Electronics for Future Colliders Conference, Chesnut Ridge (1994)

• I Ahmad, SM Austin, BB Back, D Bazin, RR Betts, FP Calaprice, KC Chan, AA Chishti, RW Dunford, JD Fox, SJ Freedman, M Freer, SB Gazes, JS Greenberg, AL Hallin, T Happ, NI Kaloskamis, E Kashy, W Kutschera, J Last, CJ Lister, M Liu, MR Maier, DJ Mercer, D Mikolas, PAA Perera, MD Rhein, DE Roa, JP Schiffer, TA Trainor, P Wilt, JS Winfield, M Wolanski, FLH Wolfs, AH Wuosmaa, G Xu, AR Young and JE Yurkon, The Atlas Positron Experiment-APEX, Proceedings of the 10th Winter Wkshp on Nuclear Dynamics (Snowbird, 1994), ed. by J Harris, A Mignerey and W Bauer (World Scientific, Singapore) 47 (1994)

• FLH Wolfs, CA White, DC Bryan, CG Freeman, DM Herrick, KL Kurz, DH Mathews, PAA Perera and MT Zanni, Breakup of 87 MeV 11B, Phys. Rev.C49, pp. 2538 (1994)

• MR Maier, PAA Perera, M Robertson and FLH Wolfs, The Sixteen Channel APEX Constant Fraction Discriminator, Nucl. Instrum. Methods A337, pp. 526 (1994)

• SB Gazes, PAA Perera and FLH Wolfs, FERA Readout System for APEX, Nucl. Instrum. Methods A337, pp. 174 (1993)

• FLH Wolfs, DC Bryan, KL Kurz, DM Herrick, PAA Perera and CA White, Segmented Focal-Plane Detector for Light and Heavy Ions, Nucl. Instrum. Methods A317, pp. 221 (1992)

Life Member, Sri Lanka Association for the Advancement of Science

• Presidential awards for research – 2010

• Dr. C. A. Hewavitharana Memorial Prize, University of Colombo, Sri Lanka - 1986.

Fellow - Institute of Physics, Sri Lanka