Research in Nuclear and Particle Physics has been pursued in India over the past eight decades. It has gone through ups and downs in the past and currently many opportunities exist for pursuing research in these fields both in the country and abroad. I shall discuss some of these possibilities in this talk.
Developments of various modern ion accelerators in India for delivering ion beams in a wide range of the energy have created new opportunities in carrying out innovative research and developmental activities. Focused research in the areas of nuclear physics, atomic and molecular physics, materials science and radiation biology using these state of the art accelerators are being carried out in...
The GANIL facility has a wide range beams ranging from intense stable and short-lived unstable beams (ISOL and fragmentation) including a variety of unique and state of art equipments. These are used to study the evolution of the properties of the quantum many body system, the nucleus, as a function of the three axis of nuclear physics namely excitation energy, angular momentum and the...
We provide a comprehensive discussion of the phenomenology of flavourful axions, including both standard Peccei-Quinn (PQ) axions, associated with the solution to the strong CP problem, and non-standard axion-like particles (ALPs). Presenting the general flavourful axion-fermion and axion-photon coupling, we calculate flavour-violating decays of mesons and leptons involving a flavourful axion....
By considering the nucleus as a vibrating liquid drop, and assuming the potential to be a function of the elongation β, and triaxiality γ, of the nucleus, the Bohr Hamiltonian can be solved to give the so-called K=0+, β-vibrational and K=2+ γ-vibrational bands. However, as summarized in the review by Garrett[1], very few of the observed 0+2 bands in deformed nuclei possess the properties...
The progress of nuclear instrumentation in the last hundred years is described. Some of the landmark discoveries, which became possible due to the development of new instrumentation, are explained. A connection between the early developments and the state of the art instrumentation is made.
The Variable Energy Cyclotron (VEC), at Kolkata, recently completed its 40 years of operation in 2017. Several milestones have been achieved in experimental nuclear physics, using the light and heavy ions beams from this cyclotron during the last four decades. In this talk, an overview of the intense research activities carried out in nuclear reaction studies, using beams from cyclotron during...
Non-holomorphic soft supersymmetry breaking interactions will be discussed in relation to MSSM. Unlike MSSM, it is possible to have a higgsino as a single component type of dark matter candidate while having a low electroweak fine-tuning. Muon g-2 may also be enhanced. We will also explore the bottom squark sector by studying the 2b plus missing transverse energy signal at the LHC. We will...
The study of single particle and bulk properties of the neutron-rich nuclei constrains fundamental issues of Nuclear physics like limits of existence of the quantum many body system ( atomic nucleus) and equation of state of neutron-rich matter etc [1-7]. This information has also important impact in understanding cosmic phenomena, like neutron star, nucleosynthesis, evolution of star...
In this talk the goal is to bring out why neutrinos hold a prominent place in today's physics. The neutrino is uncharged and interacts very weakly. As a consequence, over long distances it is a faithful messenger for information about its source, e.g., the sun. But the weakness of its interaction also makes neutrinos quite difficult to detect. The story of the neutrino is exciting and is yet...
The genesis of the India based Neutrino Observatory project is described briefly. The flagship experiment is based on a 51,000 ton magnetised iron calorimeter (ICAL) which aims to determine the mass ordering of the 3 tiny neutrino masses through a measurement of atmospheric muon neutrinos and muon anti-neutrinos. An 85 ton 4mx4mx10 layer mini- ICAL detector with 10 glass RPCs has been built...
Neutrinos with energies ranging from meV to EeV pervade the universe,
and play crucial roles in astrophysics and cosmology. This talk will describe
the rich phenomenology of these astrophysical neutrinos, and how their
future observations will enrich our knowledge of particle physics,
astrophysics, and cosmology.
Direct reactions are known to provide access to crucial nuclear structure information e.g. the quantum overlap between the ground state wave function of an initial nucleus and the states populated by the reaction. The case of light nuclei is of particular interest as direct reaction experiments involving isotopes at the dripline can be implemented, providing access to the nuclear overlaps at...
Empirical drops in ground-state nuclear polarizabilities indicate deviations from the effect of giant dipole resonances and may reveal the presence of shell effects in semi-magic nuclei with neutron magic numbers N = 50, 82 and 126. Similar drops of polarizability in the quasi-continuum of nuclei with, or close to, magic numbers N = 28, 50 and 82, could reflect the continuing influence of...
Nuclei in the vicinity of the N~Z line form a unique laboratory for studying many different phenomena among which the interplay of T=0 and 1 states at low energy, the role of neutron–proton pairing correlations, the shape coexistence along the N=Z line, the role of isospin symmetry and to which extent it is violated. A special emphasis is put on the heaviest N=Z nuclei located to the doubly...
The ElectroMagnetic Mass Analyser (EMMA) is a new experimental facility at TRIUMF. Located after the ISAC-II accelerator, EMMA is a symmetric QQEDEQQ-type mass spectrometer capable of separating recoiling nuclear reaction products from the beam. With the low emittance radioactive beams delivered from ISAC-II at energies up to at least 6.5 A MeV, EMMA is designed for fusion evaporation and...
The decay rate of neutrinoless double beta process is expected to give the first direct measure of the neutrino mass, if the corresponding nuclear matrix element can be reliably calculated [1]. A major complication in extracting the neutrino mass from the half-life of this decay is the uncertainty in the nuclear matrix element. There are certain experimental observable that may be placed to...
We propose a fermionic dark matter model by extending Standard Model with a Dirac fermion and a real pseudoscalar. The fermion dark matter particle interacts with the Standard Model sector via the Higgs portal through a dimension five interaction term as also through a pseudoscalar interaction term. The parameter space of the model is then constrained by using the vacuum stability and...
Nuclear Data evaluation is a very essential part of Experimental nuclear research. The Nuclear Structure and Decay Data Evaluation evaluation is a source to many new experiments and new ideas, besides the standardization of experimental data.
Mass A=139 data evaluation led to a new experiment for measuring the half life of 139Ba which had several past measurements not in agreement. The same...
Lower dimensional field theoretical models, e.g. Schwinger model, Chiral Schwinger model, Non-Confining Schwinger model, Thirring-Wess model and its Chiral generation known as Chiral Thirring-Wess model are of great interest because the models can explain the mass generation via dynamical symmetry breaking. It was known that the Schwinger can explain the confinement of fermions. However, in...
The structure of nuclei around the line of stability with A~200 exhibits diverse excitation modes ranging from collective rotation, including decoupled and semi-decoupled bands, and isomeric states whose decay rates span a large range from enhanced to hindered in comparison with single-particle estimates. The evolution of collectivity and the gradual predominance of intrinsic excitations with...
The parton saturation behaviour at small-x is shown in a semi-analytical solution of the nonlinear GLR-MQ equation with parton recombination corrections, which resembles the widely discussed BK saturation of gluons. The effect of gluon shadowing on the small-x and moderate-Q^2 behaviour of gluon and singlet quark distribution function is examined. The computed results are compared with...
Discovery of Higgs boson confirms once again the stupendous success of
the Standard Model (SM) of particle physics. Nevethless, there are many
experimental and theoretical issues which SM fails to address convincingly,
leading us to think about more bigger description of the SM, i.e. beyond the
standard model physics. Among several beyond standard models, the supersymmetry
is the most...
Nuclear isomers are beginning to play an ever important role in unravelling the nuclear structure changes at higher spins and excitations. The seniority isomers constitute a separate class of isomers which are not exactly spin isomers. Very recently, we have shown the emergence of a new class of seniority isomers for the first time, which decay by odd-multipole transitions. This finding has...
The mass and nature of neutrinos play an important role in theories beyond the standard model. It is now well established that neutrinos have a non-zero mass, but whether the neutrino and anti-neutrino are the same (Majorana particle) or distinct (Dirac particle) is still an open question. At present, neutrinoless double beta decay (NDBD or 0𝜈𝛽𝛽), is perhaps the only experiment which can...
The advent of Radioactive Ion Beam facilities and subsequent explosive growth in the studies of neutron rich nuclei near the drip line has opened up new vistas in modern nuclear physics. The discovery of halo structures, both 1-neutron and 2-neutron halos, in neutron-rich, light nuclei has been a significant development in nuclear structure studies. The 2-neutron halo nuclei can have both...
Flavour Physics is perhaps the only way to look beyond the Standard Model if the new particles are beyond the direct production reach of the LHC. While the three-generation CKM picture works very well, there are enough reasons to believe that this is only an effective theory. In this talk, I will discuss about the way flavour data can act as a window to the unexplored land of new physics,...
In this talk we will discuss a proposal that the $\gamma$ + missing energy signal at the Belle-II detector will be a smoking gun for supersymmetry (SUSY) in the presence of a gauged $L_\mu - L_\tau$ symmetry. A striking consequence of breaking the enhanced symmetry appearing in the limit of degenerate (s)leptons is the non-decoupling of the radiative contribution of heavy charged sleptons
to...
With large neutron-to-proton ratios far from the line of stability, nuclei develop exotic structures. Systematic studies of nuclear radii closer to the drip line have demonstrated the change of nuclear properties, such as the emergence of nuclear halo, development of neutron skin and the nuclear deformation. Halo nuclei show unexpected behavior, such as, large interaction cross section which...
This presentation will highlight some of most recent results concerning experiments
devoted to the understanding of cluster structures in atomic nuclei. Selected topics will
cover results from experimental studies on 12 C, self-conjugated and non-self-conjugated
nuclei, clustering effects in nuclear reactions with light partners, including those of interest
in nuclear astrophysics, and in the...
Astrophysical s-process is among the principla processes which are responsible for creation of heavy elements beyond the iron peak nuclei. Radiative neutron capture reactions in the vicinity of nuclear shell closures are important to understand the abundance of various heavy elements. Semi-microscpic calculation has been carried out in isotopes near magic numbers for neutron capture reactions....
The study of the excited states in nuclei is the key to understand not only the structure of nuclei but also the modes of generation of angular momentum in nuclei and different quantum mechanical symmetries in nuclei. In order to predominantly excite a particular set of states in a nucleus, one has to choose a suitable reaction. For example, the heavy-ion induced fusion reaction mostly...
We study the minimal type-III seesaw model to explain the origin of the
non-zero neutrino masses and mixing. We show that the naturalness arguments
and the bounds from lepton flavor violating decay (μ → eγ) provide very
stringent bounds on the model along with the constraints on the stability
of the electroweak vacuum up to High energy scale. We perform a detailed
analysis of the model...
The light particle induced reaction cross-section data are of prime interest for the different areas like radiation dose estimation, radiation damage, fuel cycle assessments, transmutation of long lived nuclei and many more. The future nuclear reactors like Accelerator Driven Subcritical systems (ADSs), International Experimental Thermonuclear Reactor (ITER) and fast breeder reactors demand...
We explore a two component dark matter model with a fermion and a scalar. In this scenario the Standard Model (SM) is extended by a fermion, a scalar and an additional pseudo scalar. The fermionic component is assumed to have a global U(1)$_{\rm DM}$ and interacts with the pseudo scalar via Yukawa interaction while a $ℤ_2$ symmetry is imposed on the other component – the scalar. These...
Recently, some unexpected phenomena in various B meson decays are being observed in several experiments. Few of the observables are branching ratio of $B_s→φμ^+ μ^-$ decay, angular observable $P_5$' in $B→K^* μ^+ μ^-$ decay, lepton flavour non-universality parameters $R_{K(^*)}$,$R_{D(^*)}$ etc. The fact that these observables show significant deviation around 3σ from their standard model...
In heavy-ion fusion reactions, the energy of the projectile couples with the intrinsic degrees of freedom of the target during the collision process and this leads to a dissipative phenomenon. Consequently, the dissipation in the system causes the angular momentum hindrance during the fusion process. Here we have focused on the dissipative behavior of the fusing nuclei and its dependency on...
Interpretation of data from MiniBooNE experiment at Fermilab and liquid scintillator neutrino detector (LSND) with a two-neutrino oscillation model, i.e, muon neutrino to electron neutrino, shows that, MiniBooNE experiment confirms the fourth neutrino flavour. These flavour’s properties and behaviours raise a lot of opportunities and challenges to understand the universe. In this present work,...
Search for the new elements has been one of the major area of research activity in physics and
chemistry over last few decades. Elements up to 294Og (atomic number Z = 118) have been synthesized
successfully using fusion evaporation route, where either double magic nuclei 208Pb (in the synthesis
of Z = 104 -113) or 48Ca (Z = 114 - 118) were extensively used due to extra stability achieved from...
Abstract
Human eye is limited to observe any thing under a short range of EMR (400nm-700nm) in 3D space and even by using various instruments (SEM, TEM, XRD, XPS, NMR, LHC etc) the scientist were succeeded in broadening the range of observation in EMR but still, could not unlock the 4D space concept. For 4D-space Universe, We must understand the conceptual mechanism that how the constituents...
The investigation is made to extract the total reaction cross section from a previous work where the elastic scattering of the tightly bound 10B on the 58Ni target was measured, at energies close to the Coulomb barrier. Total reaction cross sections were extracted from the elastic scattering analysis using the Optical Model with double-folding type potentials. We have also taken the total...
Information theory studies the quantification, storage, and communication of information. It was originally proposed by Claude E. Shannon in 1948 to find fundamental limits on signal processing and communication operations such as data compression, in a landmark paper entitled "A Mathematical Theory of Communication".
A key measure in information theory is "entropy". Entropy quantifies the...
A large number of cosmological observations suggest that the present universe is undergoing an accelerated expansion. The driving force responsible for this expansion is called dark energy (DE). A number of cosmological models have been proposed to account for this unknown DE component and a scalar field quintessence model is one of the main candidates for Dark Energy. The quintessence scalar...
In this paper, we have studied $B^-→l^-\bar{\nu}_l$ decay in the presence of magnetic field in two-Higgs doublet model (2HDM). The decay rate of the process is calculated both in the presence of magnetic field and in the absence of magnetic field in standard model (SM) and 2HDM. In the SM, the leptonic decay of charged B meson $B^- (p)→l^- (k) \bar{ν}_l (q)$ [1,2] originate from...
The nuclear dipole polarizability - a second-order effect in Coulomb-excitation perturbation theory competing with the reorientation effect that varies with the shape of a nucleus and splitting of magnetic substates – governed by the dynamics of the giant dipole resonances has been investigated along with the effects of recently observed enhancement of photon strength functions at low...
Excited high spin states in 66Zn, populated in the fusion evaporation reaction 52Cr(18O, 2p2n), have been studied using in-beam γ-spectroscopic methods. The Indian National Gamma-ray Array (INGA) equipped with fourteen Compton suppressed Hp-Ge clover detectors was used to detect the gamma-rays emitted by the de-exciting nucleus. The 18O beam at 72.5 MeV was supplied by the 15UD Pelletron...
Excitation function of the proton induced natSn reactions below 22 MeV for
reactor applications
Siddharth Parashari1,*, S. Mukherjee1, B.K. Soni1, R. Makwana1, S.V. Suryanarayana2,
B.K. Nayak2 and H. Naik3
1Depratment of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda,
Vadodara-390002, INDIA.
2Nuclear Physics Division, Bhabha Atomic Research Centre,...
The data for the work has been obtained from the experiment performed at Variable
Energy Cyclotron Centre, Kolkata using the INGA facility. A self-supporting 232Th target
of thickness ~25 mg/cm2 was bombarded with 30 MeV α particles. A total of six
compton suppressed clover Ge detectors and one LEPS detector were used in the
array.
By analyzing the two-fold coincidence data, a complete...
Investigation of high spin states of trans-lead nuclei attracted much attention in recent years. But nuclear structure of such nuclei largely remains unexplored mainly because of the difficulty in production via fusion-evaporation reactions along with large background due to much stronger and competing fission channel. Also the difficulty in extracting the targeted information and...
We consider the existence of a fermionic dark matter along with the extension of the Standard
Model (SM) of particle physics by the two Higgs doublet model. The Yukawa interaction of
the Higgs doublets with the SM fermions, in the Lepton Specific configuration, is responsible
for the generation of the latter’s mass. The two doublets couple to the dark matter (fermionic
singlet) through a...
A.Biswas1,2, U. S. Ghosh1, B. Mukherjee1, S. Rai1,3, K. Mondal1, A.Chakraborty1,
A. Sharma4, S. Muralithar5, R. P. Singh5 and U. Dutta6
1Department of Physics, Siksha-Bhavana, Visva-Bharati, Santiniketan, Bolpur - 731235, India
2Department of Physics, A. M. College, Jhalda, Purulia – 723202, India
3Department of Physics, Salesian College, Siliguri Campus, Siliguri - 734001, India
4...
We present the design of an indigenously developed coincidence gamma spectrometry setup with a custom built 1K Multi-channel Analyzer with an external trigger input. In addition to its own discriminator input signal generated from the shaped pulse fed to a comparator with an adjustable threshold setting, it also interprets a secondary trigger of configurable width supplied from another...
The ground-state configuration of 35Al has been studied via Coulomb dissociation
(CD) [1] using the LAND-FRS setup (GSI, Darmstadt) at a relativistic energy of ∼403 MeV/nucleon. The measured inclusive differential CD cross section for
35Al, integrated up to 5.0 MeV relative energy between the 34Al core and the neutron using a Pb target, is 78(13) mb [2].The exclusive measured CD cross section...
The study of Hg isotopes ($Z$=$80$), close to doubly magic $^{208}$Pb ($Z$=$82$), provides an opportunity to study the interplay between collective and intrinsic excitation mechanisms. High-spin data in neutron-rich Hg nuclei are not as well established as in the proton-rich region. The neutron-rich region can be reached through projectile fragmentation and multi-nucleon transfer reactions....
The excited states of 78Se have been investigated using alpha beam through the 76Ge(α, 2n) fusion evaporation reaction. The 30 MeV alpha beam was delivered by the K-130 Cyclotron at VECC, Kolkata. The target was prepared through centrifuge process of enriched metallic 76Ge powder on mylar backing. The target used in this experiment was 2mg/cm2 thick and two such targets staged together to...
Introduction
Detail study on nuclear structure in mass region A∼60 reveals various interesting phenomena. Both single particle and collective excitations with various shapes, namely, prolate, oblate and triaxial have been observed in this region in many Cu, Zn and Ni nuclei [1,2,3,4,5]. Here the lower excitations are due to the negative parity 2p3/2 , 1f5/2 and 2p1/2 orbitals but most of...
Nuclei just below the doubly magic 208Pb (${\it Z}$=82, ${\it N}$=126) are near-spherical and isomers are realized due to the hindered decays from states with predominantly high-j contributions to those with relatively lower-j values. The high-j orbitals in this region are h$_{11/2}$ for protons and i$_{13/2}$ for neutrons. Tl (${\it Z}$=81) isotopes correspond to one proton hole and a few...
Nuclear metastable states with half-lives longer than a few nanoseconds may be found in many nuclides in the nuclear landscape. With the increasing sensitivity of different measuring techniques, a number of new isomers are being discovered with various spectrometers at new accelerator facilities. These isomers provide a tool to study the different nuclear structure models. Furthermore, a wide...
Limiting mass of a white dwarf to retain stability with different remnant core composition.
Bijan Kumar Gangopadhyay
Sovarani Memorial College, Jagatballavpur, Howrah
email id: bkgangopadhyay@gmail.com
ABSTRACT
White dwarfs are remnant of sun like stars which now a day...
A model of elementary particles defined in $4 +1$ space time dimensions
naturally provides a candidate for the dark Matter. The hall mark of such a model is the presence of Kaluza Klein excitations of our known Standard Model fields. We will discuss a possible search strategy of such a model at the Large Hadron Collider.
Neutron-rich nuclei in the mass region A~100 exhibit large variety of interesting nuclear
structure phenomena. The nuclei having neutron number N ≤ 58 has a nearly spherical ground
state, but they undergo a rapid shape transition from nearly spherical to well-deformed prolate
deformation as N = 60 is approached. This abrupt shape change was correctly described by largescale Monte Carlo shell...
Rutherford Backscattering (RBS) technique is one of the most useful techniques to measure the hetero-structure film thickness and the composition of the sample. In this technique, sample is irradiated with light ions (usually 2-3 MeV α-particles or protons) and the elastically backscattered projectiles at large angles are detected. The mass of the target atoms could be identified from the...
The rare leptonic decays $B_{s,d} \to l^{+} l^{-}(l=e,μ,τ)$ present vital base to analyse the flavour structure of the standard model (SM) and also become potential source to dig out possible signatures of new physics (NP) beyond the SM [1]. The muonic decay $B_{s} \to \mu^{+} \mu^{-}$ has been observed at the LHC as well as the upper limits of branching ratios for other $B_{s,d} \to l^{+}...
The compilation and evaluation of nuclear structure and decay data is being carried out by the network of Nuclear Structure and Decay Data (NSDD) Evaluators- an international network established under the auspice of International Atomic Energy Agency (IAEA), Austria. India became a member of this network in 2005 with the establishment of Nuclear Data Center at Indian Institute of Technology,...
Investigation of the structure of atomic nuclei in the vicinity of Z=82 shell closure become important due to co-existance of single particle and collective excitations. Three high-j obitals viz. d5/2 , h11/2 and h9/2 lie near proton Fermi surface along with low-j s1/2 and d3/2 orbitals, resulting in number of K-isomers in this mass region.
The iridium isotopes (Z = 77) are located in the...
It will be a pedagogical talk on neutrinoless double beta decay. I will discuss the importance of lepton number violation, Majorana masses of neutrinos, and other processes related to neutrinoless double beta decay.
The magic numbers of the nuclei, proposed by Mayer and Jensen are a benchmark of nuclear
structure. The underlying shell gap is a characteristic of the mean nuclear field which takes into account
of many ingredients of the nucleon-nucleon interactions. Recently, it has been noted that these magic
numbers are no longer valid in the exotic nuclei which are far away from the β-stable line and...
Phase structure of QCD is interesting in its own and existence of a possible Critical End Point (CEP) in QCD phase diagram is under active investigation, both in theoretical and experimental fronts. The system created in heavy ion collisions has a finite size and motivates us to work on possible finite size effects on QCD phase transition on the theoretical side. In this work, we have used a...
Singlet fission (SF), a process whereby one high energy singlet exciton is converted into two lower energy triplet excitons, is an excited state phenomenon with a potential impact on the efficiency of inexpensive organic solar cells [1,2]. In this process high energy singlet exciton, resultant from the absorption of a high energy photon, is converted into two triplet exciton which increase the...
Corresponding author: skundu91phys@gmail.com
Quantum Chrmodynamics is an important subject of study at the colliding beam experiments. Event-Shape Variables (ESVs) are functions of the four-momenta of particles in hadronic final states and are theoretically robust. They are sensitive to both perturbative and non-perturbative aspects of QCD and help us understand the flow of energy in an...
The nuclear transport calculations are crucial for the optimization of the reactor design parameters. The nuclear data from the different nuclear data libraries are used for such transport calculations. There are several nuclear transport codes are available such as MCNP, FLUKA, GEANT4, etc. The Monte Carlo based N Particle code i.e., MCNP code is a worldwide used for such particle...
The pursuit of experimental nuclear physics at both the teaching as well as research level is,
at times, prohibitively difficult owing to the required resources and allied expenses. In
addition to the expenditures, the burden of maintaining the setups through massive and
prolonged usage is often a bottleneck in upholding the quality of training that the laboratory
course aspires to impart. As...
This paper deals with the possibility of magnetic coronal rotation and its dependence on solar rotation. A study of green coronal rotation confirms that differential rotation degree varies symmetrically through a solar cycle 1. The coronal fields shows much less differential rotation than photosphere 2. The coronal magnetic fields shows similar features as coronal green lines. The differential...
In recent years, semileptonic decays of bottom hadrons are in the focus of many theoretical as well as experimental studies due to increasing experimental evidences of new physics (NP). One of the most important ways for searching NP is to analyse rare B meson decays which are induced by flavour changing neutral current (FCNC) transition. Generally FCNC processes are forbidden at the tree...
Angular spectra of the unusual spiky events produced in 32S-Ag/Br interactions at ultrarelativistic high energy are analysed by the method of continuous wavelet transform in different scale for the ring-like structures which could indicate either the production of Cherenkov gluons or the occurrence of Mach shock waves in excited nuclear matter. The analysis is based on the assumption that the...
