Annexure-i justification of Building funds

Participation in Neutrino Physics Program using INO - India-based Neutrino Observatory
During next 10-15-years, several faculty members of the department would participate in the Neutrino Physics Program of the Country. In this regard, jointly Department of Atomic Energy and Department of Science and Technology have proposed a 1300 Crore Rupee Mega science project near Mysore. This experiment would require big 2mX2m more than 12000 Resistive Plate Chamber detectors and also, huge efforts on Neutrino Physics and detector simulation. Panjab University group members have started working on the Detector development, theoretical aspect of Neutrino physics and physics simulations.
Detector Development Facility Created:

Panjab University group established the various modern detector development facilities during the course of these years starting from the collaboration with the DZERO detector at Fermilab to the latest on-going CMS detector at CERN. These facilities include:

Scintillator Based Detector

To provide the coverage to the DZERO detector from the cosmic muons (forming one of the background signals) and vetoing them, the local HEP group started the R & D work and setup the scintillator based detectors. A prototype was developed which was approved by the collaboration. This whole activity allowed us to develop local zigs for testing the WLS (wave length shifting) fibers for attenuation studies, bonding-coupling of fibers with the light guide and shaping the scintillators for maximum light gathering. The whole setup was CAMAC controlled.

This expertise with the scintillators led to the participation in the CMS Outer Hadronic detector. Thousands of scintillator based detectors were cut/polished/assembled and fabricated with embedded optical fibers with the help from the Central Tool Room, Ludhiana. These were all tested for quality checks locally and where shipped to CERN for installation in the CMS detector.

Gaseous Based Detectors:

Under these category of detectors, the group took the responsibility along with BARC, Mumbai to set-up the lab for assembly and testing of Resistive Plate Chambers(RPC) for Muon Detector upgrade. The overall work included: Fabrication and testing in India and then testing, Installation and Commissioning of Indian RPC at CERN with CMS Detector. For this work a new gaseous detector development lab was setup in the department with 4 channel automatic gas mixing and distribution system. The CAMAC based DAQ is being upgraded with the VME based system.

Since the group is involved in the INO-ICAL (India based Neutrino Observatory-Iron Calorimeter) experiment which also uses RPCs as the active medium, it was obvious to use the existing facilities for the detector development work for the INO-ICAL. The RPCs used in INO are glass based where as the ones used in CMS are Bakelite based. The group has gained expertise in all the aspects of RPC fabrication, testing (using the cosmic test stand), scintillator paddles/telescope assembly and testing of its response, for both the glass as well as Bakelite.
Projects handled by the HEP Group

(Since 1999 till date)

Number of Projects: 8 (funded by DST, DAE-BRNS)

Total Amount of Projects: ~ Rs. 12.5 Crores

Project Proposals Approved (on-going/future collaboration)

The group has joined the Fermilab based neutrino program and has put forward a proposal to participate in the detector building for the Near detector as part of the Long-baseline neutrino experiment proposed by Fermilab.

Other than National Research Institutes, Panjab University has been a major centre being heavily supported by DST and DAE to have active participation in prestigious LHC(CERN) program. Govt. of India has placed the LHC program under Mega Project programe as India has Been recognized as Assosiate Member state of CERN and being considered as member state. Thus very active participate of this University in this program has National interest.

A2. Theoretical High Energy Particle Group:

Over the last 15 years both in collaboration with an International group based at the Abdus Salam International Centre for Theoretical Physics, Trieste, Italy and independently Prof. C.S. Aulakh and his students have developed Left Right Supersymmetric models and the the Minimal Supersymmetric SO(10) Grand Unified Theory in a sustained way that has brought these theories to the point where these theories are now in active confrontation with the lates data from the LHC, Dark Matter experiments as well as contributing a testable locus for Lepto-Baryogenesis and Inflationary Cosmology. His work is well recognized by over 1800 citations in the International literature and has resulted in a number of invitations to speak at International Conferences, and direct national (SERC-THEP) and international (ICTP-Summer School in Particle Physics). The theory group has also established a High Performance Computation Centre with Tera-flop supercomputation facilities on a 80 node cluster. These facilities are expressly set up to be of use in the research program of the Theoretical High Energy Physics, Nuclear Physics and Condensed Matter Physics Groups which are already using them intensively.

The HEP theory group has made important contributions which are well recognized at the national and international level. Some of the well recognized contributions of the group concerns: (i) Formulation & analysis of consistent Minimal Super-symmetric models of the corresponding Grand Unified Theories, (ii) Texture specific mass matrices and CP violation, (iii) Proton Spin Crisis(iv) Study of existence and the stability of solitonic solutions of non-linear evolution equations. The group proposes to carry out the following activities in the coming year/s.

1. 
   Minimal Supersymmetric Grand Unified Theory:
   

In the last 7 years the generic class of left-right Supersymmetric Unified models was studied. This study together with Neutrino mass data led us to revive an SO (10) GUT model proposed by us in 1982 as the Minimal Supersymmetric GUT (MSGUT). This GUT is now known to be the minimal GUT compatible with all experimental data and is a focus of intense investigation by at least 5 groups worldwide. We developed a new method for analysing the group theory of SO(10) which enables us to calculate all group theoretic coefficients required. We have already calculated the complete spectrum and couplings at the GUT scale and used them to calculate the threshold corrections to the gauge couplings ab initio (for the first time in any GUT). We have also proposed a new scenario of Asymptotically strong unification based on this type of GUT.

In the coming year/s, we will further deepen our studies of the MSGUT and investigate the fermion spectra, GUT scale dynamical symmetry breaking, renormalization group fixed points and corrections, baryon decay and a host of other phenomenological issues that come into sharp focus once one has available the complete spectra and couplings of this MSGUT.

(b) Phenomenological Fermion Mass Matrices & CP Violation:

We have been carrying out intensive studies in the field of fermion mixings, CP violation and fermion mass matrices. In order to understand the quark mixing phenomenon at more fundamental level, texture specific mass matrices have been formulated at phenomenological level. Mass matrices based on discrete symmetry have also been studied with good results for the rare decays. Fermion flavour mixings, neutrino oscillations, neutrino mass matrices and CP violation in the leptonic sector continues to be the thrust areas at present. In the coming years, we plan to investigate intensively the possibility to find CP violation in the electronic sector and viable set of Fermion Mass matrices which are in agreement with the quark mixing and neutrino oscillation phenomena.

(c) Proton Spin Crisis: We are also investigating the ‘proton spin crisis’ within chiral quark model with configuration mixings generated by gluon exchange. In the next two three years, we plan to investigate the gluon contribution to the spin angular momentum of the nucleon in the context of Chiral Constituent Quark Model.

(e) Solitons and Solitary Waves & their physical applications: The existence of electric charged vortex of finite energy in SU(2) non-abelian Higgs model with Chern-Simons term in (2+1) dimension and the interaction of vortices in abelian Higgs model were studied in detail. We enquired the question of whether chaos and topologically nontrivial solutions can coexist in gauge field theories. Painlevé analysis for ODE’s and its extension for PDE’s was used in these studies. The expertise developed here has been profitably used in obtaining exact solitary/soliton solutions for various non linear evolution equations like derivative coupled non linear Schrödinger equation, 5th order KdV equation non linear sigma model (in the DCC context ) The stability of these solutions and applications to various physical phenomena is one of our research interests.

During the last few years, various aspects of supersymmetric quantum mechanics and the application of this formalism to various physical situations have been studied. Some of the applications are in the area of information theory, in rearranging the information entropy in a given system, Nonlinear Physics, Atomic Physics and Particle Physics. We use a fractional transformation to connect traveling wave solutions of the nonlinear Schrödinger equation, phase-locked with a source, to the elliptic equations. Bright and dark solitons are obtained in the suitable range of parameter values.

A3. Theoretical Astrophysics

We have recently started working on the galactic chemical abundance evolution (GCE). The idea is to understand the complete galactic elemental (isotopic) evolution of our galaxy and probably other galaxies. There has been revolutionary development in the stellar nucleosynthesic theories in almost all the stellar evolutionary models. As a result the GCE models could be made much more efficient now. We have been recently working on some of the aspects of GCE models and hopefully will be able to develop my own model.

We will continue to work in GCE models for our galaxy and probably other galaxies. In addition, we would like to initiate some work in the laboratory simulation of irradiation of grains by energetic particles to study the production of short-lived nuclides that are found to be present in the early solar system.

Non-commutative Geometry

Although it has a longer history, the idea that configuration-space coordinates may not commute has arisen recently from string theory. Noncommuting spatial coordinates and fields can be realised in actual physical situations. Therefore, many physicists have investigated what follows just from the idea that coordinates are operators that do not commute. Noncommutative field theories, which are the field theories in which the coordinates do not commute, have many novel features. Our aim was to further these investigations. We studied some aspects of noncommutativity in field theory, strings and membranes.

Noncommutative field theories should be properly understood as lying somewhere between ordinary field theory and string theory. From these models we may learn something about string theory and the classification of its backgrounds, using the somewhat simpler techniques of quantum field theory. Extension of our results of noncommutative electrodynamics to higher orders and further studies of deformed symmetries, including supersymmetric.

The group has extensive cordial, professional relationship with other Institutions through collaborations and visits. The faculty participates in International / national workshops, seminars and conferences and invites visitors under TPSC programme. Participation in Indian Neutrino Initiative (INO), Associateship at ICTP, Visiting Scientist position at IUCAA, DAAD fellowship are some of the honors the group received recently. With this expertise, the group is confident in holding Winter /Summer schools and take up long term collaborative research projects.

(B). Nuclear Physics

Experimental Activities

In House Facilities:

B1. Chandigarh Variable Energy Cyclotron:

Current activities:

Chandigarh Variable Energy Cyclotron is an unique facility amongst the Universities in India. It has been functioning satisfactorily since last many years. This machine has been mainly used to produce 3.0 MeV protons and is being used as a regional facility for PIXE and polymer irradiation experiments. A new beam line (zero degree) for general purpose experiments is under progress.

(a) PIXE and PIGE Programme:

The low-energy proton beam (~ 3 MeV) is very much suitable for elemental analysis using PIXE and PIGE techniques. At present, Cyclotron is being used effectively for determination of trace elements in Archaeological, bio-medical sciences, Forensic science, aerosol samples etc. Our next aim is to make use of PIGE and RBS facilities along with PIXE for elemental analysis for a variety of samples from various fields. PIGE facility will be used for the detection of light elements such as Li, B, F, Na. Mg, Al, Si and P for which PIXE technique is not suitable. The main thrust of PIGE program will be the elemental analysis of Boron in biological samples, Fluoride in water samples, detection of Al and Si in aerosol samples. PIXE and PIGE techniques will also be employed to the study of elemental constituents of some traditional medicinal plants generally used in curing many diseases and in commonly edible vegetables of medicinal and pharmacological importance. RBS facilities will be used for elemental analysis and depth profiling of the thin films. This programme will be continued for next five years.

(b) Irradiation Work:

The Studies on the effect of low energy (2 to 3) MeV proton beam irradiation on polypropylene (PP), polyethylene terephthalate (PET), polyimide (PI), ethyle vinyl acetate (EVA), polycarbonate (PC) and blended PVC/PET have been investigated at different fluences. Now the focus on polymer nano composites films have been planned for future work. Polymeric films will be synthesized by the dispersion of different concentration of nanoparticles in the polymer matrix using sol gel technique.  This work is being done in collaboration with M S University of Baroda, Vadodara. It is planned to strengthen collaboration with other Indian universities for PIXE/PIGE and irradiation experiments in the cyclotron lab.

Future Plans:

To Establish an experimental set up for the (p,γ) and (α,γ) reactions at the Cyclotron of the Department. It is planned to set up neutron activation using proton beam from the cyclotron.

Recently, old power supplies of the cyclotron magnet systems were replaced by solid state power supply, by the funding from the departmental CAS programme and a DST project for the regional PIXE programme. At present this is the only accelerator in the country available for low energy proton and alpha beam in the above energy range. We propose to upgrade the existing experimental set up and start a programme for measuring (p,γ) and (α,γ) reaction cross sections which has a direct relevance for nuclear astrophysics and nuclear data. This programme will be use full as a training ground for students of M.Sc., Ph.D. and post-M.Sc. course in accelerator physics of the department, besides its nuclear physics importance. The group efforts for next five years will also be useful for the proposed 5 MV accelerator of the Panjab University.

(a) Motivation of the programme:

Reaction rates are central in the modeling of the nucleosynthesis and energy generation. The rates are computed by integration of the reaction cross sections across an energy range defined by the plasma temperature. Normally reactions of astrophysical importance occurs at low energy (E< 10 MeV for charged projectiles and E< 1MeV for neutrons). Generally, three reaction mechanisms contribute the reaction cross section: compound, resonant and direct reaction. There are 32 stable isotopes on the proton-rich side of the chart (Nuclide between ⁷⁴Se and ¹⁹⁶Hg). The natural isotopic abundance of these nuclei is 10-100 times less than the more neutron-rich isotope. Modeling the synthesis of the p- nuclei and calculating their abundances require an extended reaction network calculation involving more than 10⁵ reactions of 2000 stable and unstable nuclei. The Hauser-Feshback (HF) theory is used in the calculation reaction cross sections relevant to the p-process nucleosynthesis, since the vast majority of the over 20000 cross sections involved cannot be determined experimentally. The p process involves radiative neutron capture and the inverse photodisintegration process, as well as proton and alpha-capture and their inverse reactions. It is therefore a key importance to measure such reaction cross sections for the reaction network model improvement, to investigate the uncertainties in the nuclear data, and in particular, in the nuclear level densities, optical model potential and gamma-ray strength functions entering the HF calculations. In order to better constrain proton and alpha-nucleus potential as well as NLD model we propose to start this research programme for nuclei A>90 (as the data in this region is less.

(b) National and International Status:

Until 1980, (p,γ) reactions were studied using the BARC Vandegraff accelerator facility. Afterwards till date there is no such programme in this direction was pursued in this country. Recently the large discrepancy in optical potential in reaction network calculation has motivated people to measure (p,γ) and (α,γ) cross section at sub-coulomb energy and to analyze with the latest knowledge of optical potential.

The microscopic optical potential (JLM) with low energy modifications is widely used for neutrons and protons. This JLM potential is somewhat not successful in explaining the available data. However, it has been argued that the iso-vector components of the JLM potential may be too weak. Indeed, in a comparison to the recent ⁷⁰Ge(p,γ) and ⁷⁶Ge(p,n) data it was found that the energy-dependence of the S-factors of this reaction and the old measurement of (p,γ) and (p,n) reactions on Se and Sr isotopes can be better reproduced when increasing the JLM imaginary depth by 70%. For the alpha optical potential there are no such microscopic potentials available and attempts to derive a global potential are restricted to fits of Wood-Saxon shapes. This further warrants more (α,γ) measurements for better under standing the optical potential. There are two recent examples of (α,γ) reactions to measure for alpha-capture on ¹¹²Sn and ¹⁰⁶Cd relevant for p-process energy range. Recently, some programmes in this direction were stated by the group from University of Notre dam (USA) and a group from Hungary. The Hungary group had used a small cyclotron like ours and Notre dam group used their 10MV accelerator to produce low energy proton and alpha beam.

(c) Method of activation technique:

Activation method is a very common technique in applied physics. This technique has recently been used in the low energy nuclear physics for the (n,γ) work in the context of s-process studies. In a high resolution charged particle capture reaction, the direct observation of the prompt capture gamma rays is a standard method (due to the excellent energy resolution of the Ge detectors). This advantage is no longer use full for A>60 nuclei due to the increasing complexity of the capture gamma ray spectra. In the above scenario activation technique is more use full. In the activation technique target of proper thickness is irradiated by stable proton and alpha beam and the induced activities were counted offline with a High resolution HPGe detector. It is a fairly simple technique and exhibits good sensitivity, and it is selective for specific reactions via the decay of the product nuclei. This aspect also allows one not only to use samples of natural composition, but offers the possibility to determine several cross sections in a single measurement.

(d) Experimental Plan:

The cyclotron laboratory already has a chamber routinely used for PIXE measurement. The Chamber has provision to put target and various kinds of detectors and also slots for mounting X-Ray and HPGe detector. A HPGe detector of 40 to 50% relative efficiency is required to carry out the above studies. Targets will be mounted in the PIXE chamber for irradiation. A surface barrier detector will be kept around 150 degree for acquiring the RBS spectra (Which will help both in beam normalization and checking the quality of the target during beam normalization). After suitable irradiation, induced activities will be counted offline. Thick lead shield will be used to reduce the back ground. The counting will be done out side the chamber to make arrangement for the reduction of the background. The cross section will be determined from the induced gamma activity. The laboratory has one very old HPGe detector and at present it is not working. We will need a new HPGe detector and we will also explore to repair the old HPGe detector for measuring life time of the astrophysically important nuclei using DSAM technique.

B2. Establishment of a New 5MV Electrostatic Accelerator:

In the next five years it is planned to concentrate on a major proposal for 5 MV Tandetron accelerator. The proposal is already defended before the Expert Committee of the DST, Govt. of India. In the next new few months we are expecting final decision from DST. The cost estimate has been projected to be Rs.60 Crores for the main machine, beam lines and some major experimental apparatus. The recurring expenditure will be about 2 Crores which include the salary of the staff, running cost of the machine and arrangement for carrying out the research programme. The facilities will also be extended to other universities and institutes in the country. Planned research programs using 5 MV Tandetron facility are (i) Cluster Physics, (ii)Neutron generation, (iii)Accelerator Mass Spectrometry, (iv) Material modification, and (v) Characterization using Analytical techniques : RBS, PIXE, PIGE, ERDA, NRA, Micro-beam facility and a time-of-flight set-up for heavy ion RBS, Masked ion beam lithography (vi) Nuclear Astrophysics (vii) PAC Experiments. It will also be used for production of radioisotopes for medical/industrial uses – New radioactive probes for PAC studies, PET sources, Positron sources for positron annihilation investigations and radio-active sources for commercial values. In addition, beam will also be given for detector testing facility – for International collaborations and Radiation damage testing of silicon detectors.

B3. Activities at National/ International Level:

Nuclear Structure at High Spins:

We continue to investigate the high spin states in the nuclei populated through fusion-evaporation reactions using heavy-ion beams from pelletron accelerators at the IUAC and TIFR accelerator facilities. Reactions will be investigated through in-beam -ray spectroscopic techniques using the Clover detector spectrometers INGA for gamma-spectroscopy studies and HYRA for recoil tagging, and the ancillary equipments - neutron detector and charged particle ball. Active participation of the group will be there in setting up of the world class facility involving a Clover detector array along with the other ancillary equipments at IUAC. Fabrication of charge particle detectors (MOSIAC type) and associated electronics for coulomb excitation experiments is planned for the Heavy Ion Coulomb excitation studies, particle-gamma coincidence technique is used to select the impact parameter. The position sensitive particle detector thus allows to perform several logical experiment during a single accelerator run. Also the gamma ray spectra can be corrected for Doppler broadening on the basis of known angle of recoil of particle and emitted gamma-rays to improve the energy resolution. Life time measurements of excited nuclei will be continued through DSAM and RDM techniques.