Research

Simplicity in Complexity: A Journey Through the Physics of Nuclei

My researches have encompassed many areas in nuclear structure physics. My Ph.D. work was mainly focussed on the high spin phenomenon newly discovered at that time, the well-known "back-bending" in rotational bands and was carried out under the guidance of Prof. P. C. Sood (Padma Shri). During that period, I also gained reasonable understanding of the level density formalisms, application of group theory to symmetries in nuclei, the newly evolving mic-mac models, and the collective models. It has continued to sustain my researches in the areas of rotational phenomena, single particle and collective motion in odd-A and odd-odd nuclei, multi-quasiparticle states, super-deformation and identical bands, magnetic and anti-magnetic rotation, nuclear isomers and more recently nuclear astrophysics. By nature, I always tried to convert complicated and involved physics problems into simple understanding, and I always kept searching for simplicity in complexity. The vast amount of nuclear data generally formed the backbone of my studies. As a result, I also forayed into the nuclear structure and decay data evaluation around 2004 and became a part of the NSDD network of IAEA. It has provided me a unique perspective as well as importance of nuclear data. It also propelled me to try my hands in experimental studies and applications with the support of my graduate students. However, my first love always remained the theories of nuclei. Working with my students, Ph.D. fellows, post-docs, and many collaborators across the globe, has been an enriching experience. I am always thankful to them for being fellow travellers in this journey.

Research Themes

The High Spin Back-bending phenomenon

My early training and Ph.D. research work led me towards the field of “nuclear structure studies of deformed nuclei”. Seventies was a time when high spin physics was thriving. My Ph.D. thesis involved developing a simple exponential pairing model for back-bending phenomenon in even-even deformed rare-earth nuclei (Physical Review C18, 1906, 1978; Journal of Physics G4, 81, 1978). I followed this topic for many years, publishing several papers.

Symmetries and Identical Bands in normal deformed nuclei

I also became quite interested in the symmetries observed in the rotational structures and their close relationship with the Lie group algebra. This was also the time when the Interacting Boson Model was thriving. I will sit with loads of nuclear level structure data and try to look for some visible symmetries in the spectra. This led me to the first observation of “identical” band (IB) patterns on a wide scale in normal rotational bands around 1980. These were interpreted as “strongly decoupled bands” in odd-A deformed nuclei. First published in 1984 (Z. Physik A317, 2050, 1984; Phys. Rev. C30, 2050, 1984), it was followed up by the observation of identical band structures in a group of nuclei and interpreted in terms of SU(7) Lie group (Z. Physik A320, 648, 1985), with partial success. Later on, we tried to provide an interpretation in terms of F-spin multiplets (Modern Physics Letters A3, 743, 1988). We found many examples of the IB structures in the rare-earths (Reviews of Modern Physics 62, 393-509, 1990) and the actinide region (At. Data & Nucl. Data Tables 50, 269- 342, 1992).

Odd-Odd Nuclei, the GM splitting, and the odd-even effects

My interests shifted to 2-quasi particle and multi-quasi particle structures in deformed Odd- Odd Nuclei and even-even nuclei in the 80s. We noticed for the first time a significant odd- even effect in the K – bands in doubly odd nuclei. This was quite unusual and we could explain it in terms of higher-order Coriolis couplings in odd-odd nuclei (Phys. Lett. B209, 19, 1988; Phys. Rev. C40, 4320, 1989). These studies were further extended to explain the phenomenon of signature inversion in odd-odd nuclei also (Phys. Lett. B277, 233, 1992; Nucl. Phys. A620, 265, 1997; Reviews of Modern Physics 70, 843-895, 1998, Atomic Data & Nuclear Data Tables, 69, 239-348, 1998; 69, 239-348, 1998).

Multi-Quasiparticle States

My work on the odd-odd nuclei (which largely exhibit 2qp n-p states at low energies) was further extended to more complex states like two and three quasiparticle (2qp, 3qp) states and multi quasiparticle (MQP) states in even-even and odd-A nuclei. We observed a new phenomenon of signature reversal in 2qp states of some even-even nuclei and also explained it in terms of higher order Coriolis effects (Physics Letters B337, 240-244, 1994). The G-M rules applicable to odd-odd nuclei were generalized to 3QP states and a model was proposed for the same (Physical Review C45, 3013-3016, 1992; Physical Review C75,067301,2007). We recently developed a model for the three-quasi- particle states (3qp plus rotor model) which is being used to understand the high spin features of the 3qp bands (At. Data & Nucl. Data Tables 92, 1, 2006; Physica Scripta T125, 186, 2006; Phys. Rev. C75, 067301, 2007).

Super-deformed Bands

Experimental observation of the high spin super-deformed (SD) bands was one of the most surprising discoveries in nuclear structure physics in the last decade of the 20 th century. These bands display some very unusual properties like near rigid-rotor behaviour and total disconnectedness with normal level structures. We pointed out many new features of the SD bands like a weak oscillation in the gamma ray energies, and negative alignment (J. Korean Phys. Soc. 29, S361-S365, 1996; Physics Letters B412, 14-18,1997).

Semi-classical Methods in Nuclear Physics

Continuing this work on SD bands, we successfully applied the semi-classical methods to understand the high spin super-deformed (SD) bands. A semi-classical analysis of the conventional models such as the Particle-Rotor model and the Cranking model was carried out and several new features of SD bands were pointed out (Physics Letters B392, 243-248, 1997; Physics Letters B370, 1, 1996). In particular, a large starting spin for the band-head of the SD bands, weak oscillations and no linking transitions to normal states were shown to be closely related to the generally ignored non-linearity in the model Hamiltonian and the ensuing second order phase transition (Int. J. Mod. Phys. E9, 487-506, 2000). We have also used the new and powerful technique of the Periodic Orbit Theory (POT) to understand the dynamics of deformed nuclei. A complete periodic orbit theory of deformed systems was worked out and the role of three-dimensional periodic orbits was brought out in the context of SD bands (Int. J. Mod. Phys. E11, 1-17, 2002). We also obtained the level density of spherical systems in a novel way by using the periodic orbit dynamics (Pramana – J. Phys. 53, 243, 1999).

Magnetic Rotation Bands

One does not expect rotational spectra in nearly spherical nuclei. It was, therefore, a big surprise when well-developed quasi-rotational bands were seen in many Pb isotopes which are known to be nearly spherical in nature. The levels of the bands were strongly linked by magnetic transitions rather than electric transitions. It has now been recognized that this rotation is not of the charge density as in deformed nuclei but is rather of currents (a magnetic top). We completed a review of this area and identified as many as 178 candidates for the magnetic rotation (MR) bands all across the chart of nuclides (Atomic Data Nucl. Data Tables, 74, 283-331 (2000); http://www.nndc.bnl.gov/publications/preprints/mag-dip-rot-bands.pdf, 2007). We have used the particle-rotor model as well as the self-consistent Tilted Axis Cranking model in pursuing a theoretical understanding of this phenomenon. We also started an experimental program in this area and were successful in discovering many new MR bands along with new features like shape mixing, and crossing of two magnetic bands (Nucl. Phys. A732, 13 (2004); Nucl. Phys. A761, 1-21 (2005); Phys. Rev. C69, 014319 (2004); Phys. Rev. C66, 041303 (R), 2004). More recently, we have reviewed this phenomenon again and identified confirmed as well as not so well confirmed examples of 248 MR bands in 123 nuclides (https://arxiv.org/ftp/arxiv/papers/2303/2303.00499.pdf, 91 pages).

Anti-Magnetic Rotation (AMR) bands

A phenomenon closely related to the magnetic rotation bands was also proposed by Stefan Frauendrof, in an analogy to anti-ferromagnetism in solids. This leads to a new kind of phenomenon termed as 'Anti-magnetic Rotation' (AMR). An AMR band was first observed in an odd-A nucleus 105Cd in 2010 by our group (Phys. Rev. C (Rapid Comm) 82, 061308, 2010). This was later followed by the first example of more than one AMR band in a single nucleus, in 107Cd (Phys. Rev. C 87, 034304, 2013). Also, the first observation of an AMR and a MR band coexisting together was also made in 107Cd by us in 2015 (Phys. Rev. C 91, 014318, 2015). A more recent work compiles the present situation of the MR bands and AMR bands together in our article Atomic Data & Nuclear Data Tables 165, 101735 (2025).

Nuclear Isomers and Generalized Seniority

We formally started to work in the field of nuclear isomers in a focussed way in 2012, with the joining of Bhoomika in our group as a Ph.D. student. We prepared the first “Atlas of Nuclear Isomers” and produced a reliable data book in 2015 (Nuclear Data Sheets 128, 1, 2015). This work has now been updated, and more comprehensive Second Edition of the Atlas has also been published in 2023 (At. Data & Nucl. Data Tables 150, 101546, 2023). The idea behind this effort was to arrive at a global view of nuclear isomers and discover a new type of isomerism. Eventually, we discovered a new type of seniority isomer, which have multi-j configuration and decay by odd tensor electric transitions (Physics Letters B 753, 122 2016). We used the generalized seniority formalism to carry out many new calculations and have been able to explain the long-standing puzzle of double hump behavior of BE2 values in Sn isotopes (Nuclear Physics A 952, 62, 2016). This work has been greatly expanded to explain features of the chain of Sn isotopes, and isotopes and isotones around magic numbers and has led to a series of publications. We have also published the first book on nuclear isomers entitled “Nuclear Isomers- A Primer” in 2021 (Springer-Verlag).

Isospin dominance in n-rich systems and nuclear fission

I was attracted to exploring the possible role of isospin in neutron rich fission fragment distribution from an experiment carried out at B.A.R.C. (Mumbai) by the group of D. Biswas. It led me to propose signatures of isospin dependence in the fission fragment mass distribution of heavy nuclei, which proceeded by the path of compound nucleus formation, first published in a conference proceeding (Nucl. Data Sheets 120C, 123, 2014). This novel finding was later expanded to include the effect of weight factors of different channels in the various partitions of fission fragments (Physica Scripta 92, 2017, 094001; Physica Scripta 93, 14008, 2018; Pramana – J. Phys. 92, 35, 2019; European Physical Journal – Special Topics, 229, 2527, 2020). Application of this method to thermal neutron fission has also yielded reasonable results (Phys. Rev. C 103, 044322,2021). This is not so surprising when we realize that the isopsin becomes increasingly pure with the rise in neutron richness in nuclei. Since one of the fission fragments is always neutron rich, the isospin conservation must show up in a strong way.

Applications of Nuclear Physics to Hydrological problems and Nuclear Security

I have also applied the nuclear techniques to problems of societal applications. One of the important applications was made by using the technique of stable isotopes to trace the movement of rain over India. A primary study was made to study the isotopic composition of atmospheric moisture and isotopic fractionation of evaporating water of different isotopic composition (Isotopes in Environmental and Health Studies 51, 426, 2015; Journal of Radioanalytical Nuclear Chemistry 302, 975, 2014). Lately, I have also been providing full support and advice to the development of a nuclear security education lab at the Amity University since 2019 and providing expertise to hold a series of meetings in this area (International Journal of Nuclear Security 7, Article 11, 2022).

Nuclear Data Program in India

I established the first nuclear data program in India around 2004 and started the Nuclear Data Centre India under the aegis of IAEA. After getting a training at a workshop at IAEA in 2004 and working with Dr. Balraj Singh for more advanced experience in nuclear structure and decay data evaluation (we together evaluated the A=165 mass chain), I began a program of evaluation and training others in India. Since then, I have been involved in evaluating a large number of mass chains and many horizontal evaluations. The Nuclear Data Centre has now been shifted from IIT Roorkee to VECC Kolkata. I continue to be an expert member in the Nuclear Structure and Decay Data Network of IAEA. (EPJ Web of Conf. 239, 15004, 2020)

Publications

Letters

1. Quasi-elastic scattering for the nuclear ground state structure: An intriguing case of 30 Si
   Y.K. Gupta, B. Maheshwari, G.K. Prajapati, A.K. Jain, et al
   Physics Letters B 874, 140239, 2026
2. Enhanced B(E3) strength observed in 137La
   Md. S.R. Laskar, R. Palit, A.K. Jain, et al
   Phys. Rev. C (Letters) 104 (2021) L011301
3. Odd – tensor electric transitions in high-spin Sn-isomers and generalized seniority
   Bhoomika Maheshwari and Ashok Kumar Jain
   Physics Letters B 753, 122 (2016)
4. Effects of Coriolis and residual neutron-proton interactions in the proton emission from 130 Eu
   Monika Patial, P. Arumugam, A.K. Jain, E. Maglione, L.S. Ferreira
   Physics Letters B 718, 979 (2013)
5. Evidence of antimagnetic rotation in odd-A 105 Cd
   D. Choudhury, A.K. Jain et al.
   Phys. Rev. C 82, 061308 (Rapid Communication), 2010
6. An Empirical Analysis of Superdeformed Bands: A Semiclassical View
   Manisha Dudeja, Sham S. Malik and Ashok K. Jain
   Physics Letters B 412, 14-18 (1997)
7. Non-linear Dynamics of Particles Rotor Model and Superdeformed Bands
   Ashok K. Jain, Manisha Dudeja, Zafar Ahmed and Sham S. Malik
   Physics Letters B 392, 243-248 (1997)
8. Nonlinear Dynamics of High-j Cranking Model: A Semiclassical Approach
   Sudhir R. Jain, Ashok K. Jain and Zafar Ahmed
   Physics Letters B 370, 1-4 (1996)
9. Signature Reversal in 2-QP K=3 and 4 bands in 170 Yb
   Alpana Goel and A.K. Jain
   Physics Letters B 337, 240-244 (1994)
10. Mechanism of Signature Inversion in Odd-odd Rotational Bands
    A.K. Jain and Alpana Goel
    Physics Letters B 277, 233-237 (1992)
11. Reflection Assymmetric and Symmetric Shapes in 225 Ra; Polarisation Effect of Odd Particles
    R.K. Sheline, A.K. Jain, Kiran Jain and I. Ragnarsson
    Physics Letters B 219, 47-51 (1989)
12. Application of the VMI Model to Rotational Bands in Odd-odd Nuclei
    Alpana Goel and Ashok K. Jain
    Modern Physics Letters A 5, 2403-2406 (1990)
13. Observation of ± Fo Symmetry in F-Spin Multiplets
    Ashok K. Jain and R.F. Casten
    Modern Physics Letters A 3, 743-747 (1988)
14. Odd-Even Staggering in the K=1, 2, 3 and 4 Rotational Bands of Deformed Odd-Odd Nuclei
    A.K. Jain, J. Kvasil, R.K. Sheline and R.W. Hoff
    Physics Letters B 209, 19-22 (1988)

Selected Publications in last 10 years

1. Empirical Rules for 3QP Doublets: Role of G-M Doublets
   Manpreet Kaur, Sushil Kumar, Sukhjeet Singh, A.K. Jain
   EPJ Plus, 140:629 (2025)
2. Nuclear isomers at the extremes of their properties
   Bhoomika Maheshwari and A.K. Jain
   Eur. Phys. J. – ST, 233, 1101–1111, 2024
3. Evidence of Transverse Wobbling Motion in 151Eu
   Arunita Mukherjee, Sutanu Bhattacharya, T. Trivedi, ……A.K. Jain
   Phys. Rev. C107, 054310, 2023
4. Evidence for Oblate-Prolate Shape Coexistence in odd-A 73Br Nucleus
   Sutanu Bhattacharya, T. Trivedi, …., A. K. Jain
   Phys. Rev. C106 (2022) 044312
5. Successive neutron alignments in the yrast, neg-parity band of oblate-deformed 199Tl
   S. Suman, S. K. Tandel, S. G. Wahid, Manu T, M. Hemalatha, B. Maheshwari, and A. K. Jain…
   Phys. Rev. C106 (2022) 024316
6. Evolution of Nuclear Structure through isomerism in 216Fr
   Madhu, Khamosh Yadav, A.Y. Deo,…, A.K. Jain
   Phys. Rev. C105 (2022) 034308
7. Shape Coexistence in Proton Rich Se isotopes
   A. Mukherjee, S. Bhattacharya, …, A.K. Jain
   Bulg. J. Phys. 49, 108 (2022)
8. Puzzle on Isomeric Configurations in and around N=126
   Bhoomika Maheshwari, Deepika Choudhury, A.K. Jain
   Phys. Rev. C105, 024315 (2022)
9. Search for E(5) Critical Point Symmetry in Light Ge Isotopes
   Sutanu Bhattacharya, T, Trivedi,..,A.K. Jain
   Bulgarian J. Phys. 48 (2021) 541
10. Measurement of relative isotopic yield distribution of even-even fission fragments from 235U(nth,f) following γ-ray spectroscopy
    Aniruddh Dey,.., A.K. Jain, et al,
    Phys. Rev. C 103 (2021) 044322
11. Isospin Conservation in Fusion-Fission Reactions – Empirical Evidence
    Swati Garg, A.K. Jain, Yang Sun, Alpana Goel
    European Physical Journal – Special Topics, 229 (2020) 2527-2541
12. Evolution of Nuclear Structure in and around Z=50 closed shell: Gen. Seniority in Cd, Sn and Te isotopes
    B. Maheshwari, Hasan Abu Kassim, Norahsliza Yusof, and A. K. Jain
    Nuclear Physics A992, 121619 (2019)
13. Evolution of collectivity and evidence of Octupole correlations in 73Br
    S. Bhattacharya, T. Trivedi,…., A.K. Jain
    Physical Review C100, 014315 (2019)
14. Generalized Seniority Schmidt Model and the g-factors in Semi-magic nuclei
    B. Maheshwari and A. K. Jain
    Nuclear Physics A986, 1 (2019)
15. Test of Isospin Conservation in Thermal Neutron-induced Fission of 245Cm
    Swati Garg and A.K. Jain
    Pramana – J. Phys. 92, 35 (2019)
16. Role of Isospin and its conservation in neutron-rich fission fragments
    Swati Garg, Bhoomika Maheshwari, A.K. Jain
    Physica Scripta 93, 124008 (2018)
17. Does Compound Nucleus remember its Isospin- An Evidence from the Fission Widths
    Swati Garg and A.K. Jain
    EPJ Web of Conf.178, 05008 (2018)
18. Isospin Conservation in Neutron Rich Systems of Heavy Nuclei
    A.K. Jain and Swati Garg
    EPJ Web of Conf. 178, 05007 (2018)
19. Parity Doublet Structures in 216Fr
    Pragati, Ajay Deo,…, A.K. Jain
    Physical Review C97, 044309 (2018)
20. Δv = 2 seniority changing transitions in yrast 3- states and B(E3) systematics of Sn isotopes
    Bhoomika Maheshwari, Swati Garg and A.K. Jain
    Pramana – J. of Phys., Rapid Communication, 89, 75 (2017)
21. Goodness of isospin in neutron rich systems from the fission fragment distribution
    Swati Garg and A.K. Jain
    Physica Scripta 92, 2017, 094001
22. Generalized Seniority States and Isomers in Tin Isotopes
    A.K. Jain and Bhoomika Maheshwari
    Physica Scripta 92, 2017, 074004
23. Goodness of Generalized Seniority in Semi-Magic Nuclei
    A.K. Jain and Bhoomika Maheshwari
    Nuclear Physics Review 34, 2017, 73-81
24. Asymmetric behavior of the B(E2 ↑; 0 + → 2 + ) values in 104 – 130Sn and generalized seniority
    Bhoomika Maheshwari, Ashok Kumar Jain and Balraj Singh
    Nuclear Physics A 952, 62 (2016)
25. 6 + isomers in neutron-rich Sn-isotopes beyond N=82 and effective interaction
    Bhoomika Maheshwari, Ashok Kumar Jain, and P. C. Srivastava
    Phys. Rev. C 91, 024321 (2015)

Nuclear Data Work

1. Nuclear Data Sheets for A=165
   A.K. Jain, Anwesha Ghosh, Balraj Singh
   Nuclear Data Sheets 107, 2006, 1075-1346
2. Nuclear Data Sheets for A=218
   A.K. Jain and Balraj Singh
   Nuclear Data Sheets 107, 2006, 1027-1074
3. Nuclear Data Sheets for A=251
   J.K. Tuli, S. Singh, and A.K. Jain
   Nuclear Data Sheets 107, 2006, 1347-1392
4. Nuclear Data Sheets for A=253
   A.K. Jain, S. Singh and J.K. Tuli
   Nuclear Data Sheets 107, 2006, 2103-2129
5. Nuclear Data Sheets for A=221
   A.K. Jain, S. Singh, S. Kumar and J.K. Tuli
   Nuclear Data Sheets 108, 2007, 1-36
6. Nuclear Data Sheets for A=225
   A.K. Jain, R. Raut, and J.K. Tuli
   Nuclear Data Sheets 110, 2009, 1409
7. Nuclear Data Sheets for A=222
   S. Singh, A.K. Jain, and J.K. Tuli
   Nuclear Data Sheets 112, 2011, 2851
8. Nuclear Data Sheets for A=139
   P. Joshi, B. Singh, S. Singh and A.K. Jain
   Nuclear Data Sheets 138 (2016) 1 – 292
9. Nuclear Data Sheets for A=215
   S. Singh, A.K. Jain, and J.K. Tuli
   Nuclear Data Sheets 114 (2013) 2023
10. Nuclear Data Sheets for A=219
    B. Singh,..,A.K. Jain,..et al.
    Nuclear Data Sheets 175 (2021) 150

Major Review Articles

1. Intrinsic States of Deformed Odd-A Deformed Nuclei in the Mass Regions (151 ≤ A ≤ 193) and (A ≥ 221)
   A.K. Jain, R.K. Sheline, P.C. Sood and Kiran Jain
   Reviews of Modern Physics 62, 1990, 393-509
2. Rotational Bands in Deformed Odd-A Nuclei in the Actinide Region
   Kiran Jain and A.K. Jain
   Atomic Data and Nuclear Data Tables 50, 1992, 269-342
3. Nuclear Structure in Odd-Odd Nuclei, 144 ≤ A ≤ 194
   A.K. Jain, R.K. Sheline, D. Headly, P.C. Sood, D. Burke, I. Hrivnacova, J. Kvasil, D. Nosek, and R.W. Hoff
   Reviews of Modern Physics 70, 1998, 843-895
4. Intrinsic Structure and Associated Rotational Bands in Medium-Heavy Deformed Odd-Odd Nuclei: I
   D.N. Headly, R.K. Sheline, P.C. Sood, R.W. Hoff, A.K. Jain and D.G. Burke
   Atomic Data and Nuclear Data Tables 69, 1998, 239-348
5. Table of Magnetic Dipole Rotational Bands
   Amita Rastogi, A.K. Jain and B. Singh
   Atomic Data and Nuclear Data Tables 74, 2000, 283-331; revised http://www.nndc.bnl.gov/publications/preprints/mag-dip-rot-bands.pdf (2006)
6. Review of Magnetic and Anti-Magnetic Rotational Structures in Nuclei
   Sushil Kumar, Sukhjeet Singh, Balraj Singh, Amita, Ashok Kumar Jain
   https://doi.org/10.48550/arXiv.2303.00499 (2023); Atomic Data and Nuclear Data Tables 165, 2025, 101735
7. Table of Three-Quasiparticle Rotational Bands in Deformed Nuclei, 153 ≤ A ≤ 187
   S. Singh, S.S. Malik, A.K. Jain, and B. Singh
   Atomic Data and Nuclear Data Tables 92, 2006, 1-46
8. Atlas of Nuclear Isomers – Second Edition
   Swati Garg, B. Maheshwari, B. Singh, Y. Sun, A. Goel, A.K. Jain
   Atomic Data & Nuclear Data Tables, 253 pages, 150, 2023, 101546
9. Nuclear radius parameters (r0) for even-even nuclei from alpha decay
   Sukhjeet Singh, Sushil Kumar, Balraj Singh, and A.K. Jain
   Nuclear Data Sheets 167 (2020) pp. 1-35

Books

1. Nuclear Isomers
   Guest Editors: P.M. Walker, A.K. Jain, Bhoomika Maheshwari
   The European Physical Journal – Special Topics, Volume 233, No. 5, 2024
2. Nuclear Isomers-A Primer
   A.K. Jain, Bhoomika Maheshwari, A. Goel
   Springer Verlag, 2021
3. Role of Symmetries in Nuclear Physics
   Guest Editors: V.K.B. Kota and A.K. Jain
   The European Physical Journal – Special Topics, Vol. 229, Nos. 14-15, 2020
4. Proceedings of International Conference on Recent Trends in Nuclear Physics-2012
   Editors: Sushil Kumar and A.K. Jain
   American Institute of Physics Conference Proceedings 1524, New York, 2013
5. Nuclear Structure and Dynamics
   Editors: Ashok K. Jain and Ranjan K. Bhowmik
   Phoenix Publications, New Delhi, 2000
6. Proceedings of the Second National Workshop on Nuclear Structure Physics
   Editors: Surya N. Chintalpudi and Ashok K. Jain
   Inter-University Consortium of DAE Facilities, Calcutta, 1995