
The workshop is aimed to enhance the successful strengthening of collaboration between scientists from the Joint Institute for Nuclear Research (JINR, Dubna), an international intergovernmental research organization, and Indian research organizations and universities. The scientific deliberations will provide opportunity to the Indian scientists to explore the latest advances in experimental capabilities of JlNR provided by the NICA facility, Super Heavy Element Factory and accelerator complex of the Flerov Laboratory of Nuclear Reactions, the neutrino telescope Baikal-GVD and to discuss prospects of cooperation based at NICA-BM@N, NICA-MPD and NICA-SPD as well as Baikal-GVD Collaborations.
Due to organizational constraints, we are unable to accommodate the participation of undergraduate and postgraduate students. Please note that PhD students wishing to participate in the workshop are required to submit an abstract and arrange for a letter of recommendation from their supervisor, to be sent directly to: hic@niser.ac.in
The fragment-separator ACCULINNA-II intended for secondary beam
separation has been operating at the U400M cyclotron since 2017. The separator
is equipped with detection system, including a neutron wall, zero-degree
spectrometer and a cryogenic target cell which may be fiiled with helium and
hydrogen isotopes, including tritium. Experiments are being carried out at the
separator are mainly focused on the studies of nuclei at the proton and neutron
drip-lines produced in transfer reactions. Plans and some prospects connected
with the use of the deuterium and trium targets will be discussed
The talk is about methods and technologies of data processing in
heterogeneous computing environments in the context of Meshcheryakov
Laboratory of Information Technologies (MLIT) activities. The Multifunctional
Information and Computing Complex (MICC) of MLIT JINR is a key component of
the JINR network and information and computing infrastructure. The MICC is
regarded as JINR’s unique basic facility and plays a defining role in scientific
research, which entails modern computing power and storage systems. The JINR
computer infrastructure encompasses the IT ecosystem for the NICA project
(BM@N, MPD, SPD), which includes all the MICC computing components and
storage systems owing to grid technologies; the Tier1 grid site for the CMS
experiment at the LHC; Tier2/CICC that provides support for the experiments at
the LHC (ATLAS, ALICE, CMS), FAIR (CBM, PANDA) and other large-scale
experiments, as well as support for users of JINR’s Laboratories and Member
States; the integrated cloud environment of the Member States to support users
and JINR neutrino program; the HybriLIT platform with the “Govorun”
supercomputer as the major resource for high-performance computing. The most
important tasks are the development of new data processing and analysis
algorithms based on deep and machine learning, including artificial intelligence,
and the development of modern Big Data methods and algorithms for solving
applied problems. The development of the digital platform “JINR Digital
Ecosystem”, which integrates existing and future services to support scientific,
administrative and social activities, as well as the maintenance of the engineering
and IT infrastructures of the Institute, provide reliable and secure access to various
types of data and will enable a comprehensive analysis of information using
modern Big Data technologies and artificial intelligence.
We investigate how the intrinsic nature of fermionic dark matter (DM),
Dirac versus Majorana, affects the structure of compact stars. Incorporating DM
into a relativistic mean-field framework with a scalar portal coupling to nucleons,
we derive self-consistent equations of state and solve the
Tolman–Oppenheimer–Volkoff equations. Differences in internal degrees of
freedom lead Dirac DM to soften the EoS more than Majorana DM, resulting in
smaller stellar radii and lower maximum masses. By comparing with observational
constraints from NICER and gravitational-wave data, we show that compact star
measurements can provide insights into the particle nature of dark matter.
We explore the structure, rotation, and non-radial oscillations of
anisotropic dark energy stars, by modeling the matter using a modified Chaplygin
equation of state and adopting the Bowers–Liang prescription for anisotropic
pressure. We first extend stellar equilibrium to slowly rotating configurations under
anisotropy, solving the structure equations to obtain mass, radius, deformation,
angular momentum, moment of inertia, and quadrupole moment, and quantify how
anisotropy impacts these global properties. We then analyze non-radial $f$-mode
oscillations (for $l=2$) within the Cowling approximation, comparing isotropic
versus anisotropic models and exploring how varying anisotropy modifies the
oscillation spectra. We find that rotation under anisotropy induces significant
deformation and alters global properties, while the $f$-mode spectra show distinct
signatures that may differentiate dark energy stars from neutron or quark stars.
Our results suggest that combining rotational and oscillation behavior in anisotropic
dark energy stars provides new observable handles for their astrophysical
identification.
We constrain the nuclear matter equation of state within the relativistic
mean field model by including the isoscalar-vector and isovector-vector coupling
term at a fundamental level using the Bayesian analysis. We used the nuclear
saturation properties and recent astrophysical observations to constrain the dense
matter equation of state. We obtained about 20000 sets of equations of states out
of sampling about 60 million sets of equations of states. All 20000 equations of
state satisfy nuclear matter saturation properties at saturation densities and
produce high mass neutron stars. In our findings, we find that the non-zero value of
the scalar-vector and isovector-vector coupling parameter and the negative value
of the sigma meson self-coupling stiffen the equation of state. Our sets of
equations of state produce neutron stars of mass larger than 2.5 M$_{\odot}$ to
include the recent gravitational waves observation GW190419.
A recently developed theoretical model for the fission fragment yield
distributions, based on the nuclear energy density functional theory, will be
elaborated. The model is further extended to account for the odd-even staggering
in the fission fragments' charge yields. The predicted results for preactinides,
actinides, and superheavy nuclei will be presented and compared with the existing
results. Also, extension to finite-temperature calculations to incorporate
neutron-induced fission will be discussed.
The reaction mechanisms have been investigated intensively in many
reactions with heavy ions. Several processes can take place at the interaction of
two colliding nuclei. The main of them are fusion-fission, quasifission, fast fission,
multinucleon transfer, the formation of the evaporation residue, deep inelastic
collisions and, finally, quasielastic and elastic scattering. A big set of the
experimental data obtained in very different nuclear reactions were measured with
use of double-arm Time-Of-Flight spectrometer CORSET, which allows to
measure binary processes with high accuracy. The experiments were carried out in
FLNR JINR at U-400 and U-400M accelerators, in European scientific centers, but
several experiments were conducted in collaboration with Indian colleagues as
well. The investigated compound nuclei formed in the reactions last from
neutron-deficient 178Pt up to superheavy nucleus with Z=122. Many of the
reactions were measured in wide energy range, below and well above the
Coulomb barrier. The contribution of different processes in the mass-energy
distributions of the reaction products is mainly defined by the entrance channel
characteristics, such like mass asymmetry of the reaction partners, Coulomb factor
(Z1Z2), angular momentum and excitation energy of the compound system, etc. It
was shown that in some cases it is possible to distinguish different mechanisms
and extract their corresponding mass-energy distributions. Moreover, the applied
experimental methods give the possibility to deduce the cross-section values of
different processes. The detailed and complex analysis of mass and energy
distributions of the fusion-fission fragments indicates that not only spherical proton
and neutron shells influence on the behavior of mass and energy distributions, but
deformed proton shells either. In quasifission process which conquers with
fusion-fission the influence of shell effects was also observed. Possible ways of the
set-up development will be also discussed in the presentation. The proposed
upgrade of the spectrometer would significantly enlarge the facilities for
experimental investigations of the reaction mechanisms observed in reactions with
different entrance channel properties, and allow investigations of the structure both
reaction products and evaporation residues.
In the present study, an overview of different reaction mechanisms
involved light and heavy ion induced reactions has been investigated at low
energies below 10 MeV/nucleon. In light ion reactions, an intermediate mechanism
so called pre-compound (PCN) emission which is bridging between compound
(CN) and direct reactions (DR) is attracted significantly due to its interplay between
nuclear structures and reaction dynamics. The current understanding of PCN
mechanism is advanced through cross-section measurements for a large number
of reactions produced in the interaction of protons[1] and alpha particles beams
with target nuclei (A=59−187). These experiments were carried out for a broad
mass range at the Variable Energy Cyclotron Centre (VECC), Kolkata, India [[1-6].
The conclusions of the present investigations have achieved three key milestones
since the development of PCN dynamics; (i) the development of mass-number
dependence systematics for target nuclei (A=59−187) [7], (ii) exploration of the
target deformation effects [8], and (iii) significance of the shell structure [8]. The
PCN process was further revolutionized by bombarding the heavy-ion beams (12C,
13C, 14N, 16O, 18O and 19F) on heavy mass target nuclei (A=150-181) using
accelerator facility of the Inter-University Accelerator Centre (IUAC), New Delhi.
Since, PCN emission process is scarce in heavy-ion (HI) reactions at low energy
due to the dominance of the breakup fusion (BUF) and fission process. In the
present work, how the contribution of PCN competes with BUF and fission
process, will be presented. Nevertheless, the evidence of PCN emission in HI
reactions at low energies (4–7 MeV/nucleon) highlights the crucial role of angular
momentum in these reactions [9-10]. To further explore these effects, experiments
were conducted at the IUAC, New Delhi to measure the recoil range distributions
(RRDs) and spin distributions (SDs) of production residues for various
projectile-target combinations. Analysis of the RRD and SD data revealed two
distinct de-excitation patterns corresponding to the pre-compound and compound
nucleus processes, providing valuable insights into the low-energy reaction
dynamics of heavy-ion collisions. Further details of these measurements and
analyses will be presented.
The quark constituents of the fireball created in relativistic heavy-ion
collisions carry intrinsic spin. Whether these spin degrees of freedom fully
thermalize remains an open question. Insights from kinetic theory suggest that spin
relaxes on a longer timescale compared to momentum. Polarization observables in
experiments offer valuable probes into this issue. While the assumption of local
equilibrium for spin degrees of freedom at freeze-out successfully reproduces
global polarization data, it fails to capture the correct sign of longitudinal
polarization without invoking the isothermal approximation-indicating the presence
of nontrivial spin dynamics. Until recently, no tool has been available to study such
dynamics in detail. In this work [1], we numerically solve (3+1)-dimensional
dissipative spin hydrodynamics on top of a realistic hydrodynamic background. We
investigate the time evolution of the spin potential under three different interaction
scenarios for the QGP fireball produced in Au+Au collisions at top RHIC energy.
Our results suggest that spin degrees of freedom may thermalize within the lifetime
of the fireball. We further apply our framework to describe the spin polarization of Λ
hyperons. The results indicate that dissipative effects play a critical role in correctly
reproducing the sign of longitudinal polarization. [1] Sapna, S. K. Singh and D.
Wagner, arXiv:2503.22552
In this talk we discuss light and heavy mesons in the frame of the local
NJL-like models and in the frame of the quark model with separable interaction
kernel. The NIL-type model is known for its ability to describe the chiral symmetry
breaking and to describe the properties of matter at finite temperature and density.
However, the description of mesons within this model is limited by the number of
possible flavours of quakrs. The higher the number of flavors introduced, the more
complex the model becomes. To describe heavy mesons, we start from the
Bethe-Salpeter equation chosing the interaction kernel as $D(q-p) =
D0\phi(q^2)\phi(p^2)$ and define the meson vertex functions in Gaussian form. For
te first step we fix the model parameters using the meson electromagnetic, leptonic
decay constants of light mesons. As an application of the model, the transition
formfactorsof light and heavy pseudoscalars and radiative decays of light and
heavy vector mesons are considered. Comparisons of our results with other
calculations are performed. Also the hadronic interactions of charm and bottom
mesons were considered as a base of further study and production and absorption
in hot and dense hadronic matter.
This talk reviews the design and key features of the Baikal-GVD neutrino
telescope, which is the largest in the Northern Hemisphere. It is being constructed
in Lake Baikal, and has a detection volume approaching 0.7 km3 and is increasing
annually. Currently, the underwater installation consists of 4212 optical modules in
117 525-meter long strings. The modular design of the detector allows for data
collection during construction. This review provides an overview of the data
processing system, recent experimental results on high-energy cascades and
tracks, including confirmation of an astrophysical diffuse neutrino flux and the
existence of a Galactic neutrino component.
I will give an overview of low-energy nuclear physics research in the field
of heavy and superheavy elements done at the Flerov Laboratory of Nuclear
Reactions, JINR (Dubna). I will discuss the status of the FLNR infrastructure
development as well as current and future research. Special attention will be given
to two topics: syntehsis of superhevay elements and the program of studying and
using the multinucleon transfer reactions for producing new mostly neutron-rich
heavy nuclei.
The main goal of the Multi-Purpose Detector (MPD) at NICA facility is to
study the structure of the QCD phase diagram at high baryochemical potential. To
achieve this goal, the MPD will study heavy-ion collisions in a wide energy range of
2.4-11 GeV. By measuring a wide range of signals from heavy-ion collisions, the
MPD will investigate various physics phenomena, including the equation of state
and critical behavior of the QCD matter, the properties of in-medium hadron
spectral function, the characteristics of hyperon-nucleon interactions, etc. In this
report, we will review the status of the MPD facility and its physics program, with a
focus on the first expected measurements to be performed for Bi+Bi and Xe+W
collisions in collider and fixed-target configurations, respectively.
The Spin Physics Detector collaboration intents to perform a
multipurpose experiment foreseen to run at the NICA collider (JINR, Dubna). The
main purpose of the experiment is the study of the nucleon spin structure in
collisions of polarized protons and deuterons and other spin-related as well as
unpolarized phenomena at $sqrt{s}$ up to 27 GeV and luminosity up to $10^{32}$
cm$^-2$ s$^-1$.
Accurate estimates of (anti)neutrino spectra and luminosities are
essential for assessing the feasibility of detecting neutrinos from pre-supernova
stars. Using a recently proposed thermal quasiparticle random-phase
approximation (TQRPA) method, we investigated the effects of nuclear
temperature on pre-supernova (anti)neutrino emission. By comparing the $\nu_e$
and $\bar\nu_e$ spectra arising from neutral- and charged-current weak reactions
in cold versus thermally excited (hot) nuclei, we conclude that energy transfer from
hot nuclei not only enhances (anti)neutrino emission but also hardens the
spectrum. Using the MESA stellar evolution code, we generated density,
temperature, and chemical composition profiles for a pre-supernova model with
$M=14.\,M_\odot$. Based on these profiles, we computed the time evolution of
$\nu_e$, $\bar\nu_e$ luminosities and spectra resulting from both thermal and
nuclear processes. We find that, even one day before core collapse, the luminosity
of electron neutrinos produced via electron capture on hot nuclei exceeds by an
order of magnitude that from electron-positron pair annihilation. Furthermore, in the
context of electron antineutrino production, neutrino-antineutrino pair emission via
nuclear de-excitation (ND) is at least as significant as the electron-positron
annihilation process. We also demonstrate that flavor oscillations enhance the
high-energy contribution of the ND process to the electron antineutrino flux -- a
feature that may prove crucial for the detection of pre-supernova antineutrinos by
terrestrial detectors.
Understanding the polarization of final-state leptons in neutrino–nucleus
interactions plays a significant role in probing fundamental symmetries. We present
an implementation of final-state lepton polarization within the GENIE neutrino
event generator, focusing on charged-current quasielastic (CCQE) and
two-particle–two-hole (2p2h) scattering processes. The polarization vector of the
outgoing lepton is calculated using a covariant formalism based on the polarization
density matrix derived from the leptonic and nuclear tensors. The polarization
information is integrated into GENIE’s event record, enabling subsequent analysis
and detector response studies sensitive to spin-dependent effects. Validation was
performed for all CCQE and 2p2h models currently implemented in GENIE. This
development enables detailed studies of polarization-sensitive observables,
including lepton angular asymmetries and potential non-standard interactions
signatures in neutrino scattering. It enhances the realism of GENIE simulations
and provides a tool for more complete modeling of polarization-dependent
observables in neutrino experiments such as DUNE and Hyper-Kamiokande.
This study examines the impact of dark matter (DM) on the bulk
properties of neutron stars (NS) using the relativistic mean field (RMF) theoretical
framework. The analysis considers the neutralino with a mass of 200 GeV, as the
DM candidate. This particle interacts with baryons via the standard Higgs boson.
The investigation focuses on how variations in the dark matter Fermi momentum
(k_f^DM) affect the neutron star equation of state (EOS) and key macroscopic
observables, including maximum mass (Mmax), canonical radius (R1.4), and
dimensionless tidal deformability (Λ1.4). The NLD, IOPB, and G3 parameter sets
are employed for this analysis. The presence of DM consistently softens the EOS,
resulting in systematic decreases in Mmax, R1.4, and Λ1.4. For example, within
the NLD parameter set, Mmax decreases from 2.353 solar masses to 1.955 solar
masses, and R1.4 decreases by approximately 3.8 km as k_f^DM increases from 0
to 0.05 GeV. A third order polynomial relationships of the form R1.4, Λ1.4
=a(k_f^DM )^3+b(k_f^DM )^2+c(k_f^DM )+d are established for all parameter sets.
The functional form of this correlation is same for all parameter set while
correlation coefficients a, b, c, and d depend on the specific parameter set and the
baryonic composition. When k_f^DM is in the range of 0.04 to 0.05 GeV, certain
RMF parameter sets that were previously inconsistent with gravitational-wave
constraints become compatible with observational limits from GW170817 and
Neutron Star Interior Composition Explorer (NICER) data.
The knowledge of the
optimal collision energies at synthesis of the new superheavy elements and of the
contributions of products formed in different reaction channels to the mixed mass
distributions measured in the experiments are of the interest of experimenters. The
dinuclear system (DNS) model \cite{} developed in cooperation between
researchers of the Joint Institute for Nuclear Physics in Dubna (Russia) and
Institute of Nuclear Physics of Academy of Science of Uzbekistan allows us to
calculate the partial cross sections of reaction channels of heavy-ion collisions. It
was found that the partial fusion probability decreases by the increase of the DNS
angular momentum. The intrinsic fusion barrier $B^*_{\rm fus}$ of the potential
energy surface for the DNS configurations with the small mass asymmetry
increases by the angular momentum, since the moment of inertia of the DNS
decreases causing the increase of the centrifugal force. One of proves of this
phenomenon is the observation of the alpha-particle and corresponding conjugate
residue nucleus in the incomplete fusion. It is well known that the incomplete fusion
products are observed in collisions of the relatively light nuclei ($^{12}$C,
$^{16}$O, $^{22}$Ne, $^{28}$Si, ...) with the rare Earth elements [2]. The
theoretical results show that the competition between different reaction channels
depends on the charge asymmetry $Z_P/Z_T$, ratios $A_P/Z_P$ and $A_T/Z_T$
of the mass and proton numbers in the projectile and target nuclei, orientation
angles of their axial symmetry and initial orbital angular momentum [3]. The last
two physical quantities can not be controlled in the experiments, therefore, their
role in the complete fusion mechanism can be studied mainly on the base of
theoretical models. The hindrance to complete fusion is studied as the increase of
yields of the quasifission products in the heavy ion collisions. 1. A. K. Nasirov {\it et
al}., Nucl. Phys. A {\bf 759}, 342 (2005). 2. Abhishek Yadav {\it et al}., Phys. Rev. C
{\bf 107}, 044605 (2023). 3. A. K. Nasirov {\it et al}., Eur. Phys. J. A {\bf 55}, 29
When two massive nuclei collide, the reaction leads to the capture of the
heavy-ion projectile into the heavy target nucleus and forms a dinuclear system
after the collision. The system goes through a large-scale collective rearrangement
of the nucleonic matter and develops into an equilibrated compound nucleus (CN),
known as the complete fusion process. However, if the dinuclear system fissions
before reaching the stage of an equilibrated compound nucleus, the reaction leads
to fusion suppression due to the nonequilibrium quasifission (QF) process. The
strong Coulombic repulsion in the heavy-ion collision reactions leads to faster
interaction and short sticking time between the colliding nuclei that eventually give
rise to the QF process. At near the barrier energy, this later process is by far the
dominant reaction mechanism behind the fusion hindrance that causes
suppression of the evaporation residue formation in the super-heavy region of
elements. Therefore, the perennial challenge to produce the SHE nuclei primarily
resides on our understanding of the two competing processes - fusion-fission (FF)
and quasifission (QF) in the heavy-ion fusion reactions. With this motivation, the
following experiments were performed at the Flerov Laboratory of Nuclear
Reactions (FLNR), JINR, Russia using energetic beams of 16O and 48Ca
delivered from the U400 cyclotron. Thin targets of 208Pb and 176Yb were
bombarded with the 16O and 48Ca beams, respectively at different energies
above the Coulomb barrier to produce the same fissioning nucleus, 224Th. The
measurements of the reaction binary products were carried out by utilizing the
double-arm time-of-flight (TOF) spectrometer CORSET. The Mass-Total Kinetic
Energy (M-TKE) distributions of the primary binary fissionlike fragments are further
utilized to separate different reaction mechanisms involved. Multimodal analysis is
carried out on the experimental mass and energy distributions of the binary
fissionlike fragments to investigate the possibilities of different fission modes.
Detailed description of the experimental investigation and recent preliminary
results will be discussed during the workshop. In addition, our future experimental
proposals in joint experiment between JINR and various Indian facilities will also be
discussed during the workshop.
Present
work provides a review about experiments carried out with separators GRAND
[1-2] and SHELS [3-4]. The latter is a modernization of the kinematical electrostatic
separator VASSILISSA [5–6]. GRAND is a new gas-filled separator designed to
operate with high-intensity beams delivered by the cyclotron DC-280. It was
constructed within the framework of the SHE Factory project [7] in 2019. Several
types of detection systems are employed on both separators. The SFINX system
[8] is applied to measure the yield of neutrons per act of spontaneous fission (SF);
the GABRIELA detector array [9] is used for α-, β-, and γ-spectroscopy of nuclei;
and a silicon “CryoDetector” operating under a temperature gradient is utilized for
chemical studies of SHE. The investigations were performed in the region of
neutron-deficient nuclei with atomic numbers Z = 94 and 102 (see Pic. 1) in
complete fusion reactions of 204,206,208Pb with 26Mg and 48Ca ions. A new
isotope 227Pu was discovered [10]. In reactions of 207Pb and 238U with 22Ne,
26Mg and 54Cr ions, the yield of neutrons per act SF was measured and the decay
mode for nuclei with Z = 102, 104 and 106 were studied, see Pic 1. Pic 1. Nuclear
map, where the isotopes studied in experiments are indicated by frames.
[1]Kuznetsova A.A., Bulletin of the Russian Academy of Sciences: Physics, 2023,
Vol. 87, No. 8, pp. 1105–1111. [2] A. V. Yeremin, A. G. Popeko, A. I. Svirikhin, et
al., Phys. Part. Nuclei Lett. 21, 518–525 (2024). [3] Yeremin, A.V., Popeko, A.G.,
Malyshev, O.N., et al., Phys. Part. Nucl. Lett., 2015, vol. 12, no. 1, p. 35. [4]
Yeremin, A.V., Popeko, A.G., Malyshev, O.N., et al., Phys. Part. Nucl. Lett., 2015,
vol. 12, no. 1, p. 43. [5] Yeremin A.V., et al., Nucl. Instr. and Meth. B 126 (1997)
329. [6] Malyshev O.N., et al., Nucl. Instr. and Meth. A 440 (2000) 86. [7]
Gulbekian G. G., Dmitriev S. N., and. Itkis M. G, Phys. Part. Nucl. Lett. 16, 866
(2019). [8] Lopez-Martens A. et al. (Gabriela Collab.), Eur. Phys. J. A 58, 134
(2022). [9] Isaev A. V., Yeremin A.V., Zamyatin N. I. et. al., Phys. Part. Nucl. Lett.,
2022, vol. 19, no. 1, p. 37. [10] A.A. Kuznetsova, A.I. Svirikhin, A.V. Isaev et al,
Physics of Particles and Nuclei Letters, 2025. ISSN 1547-4771, 2025, Vol. 22, No.2, pp. 406–412.
Nowadays applying of multinucleon transfer reactions (MNT) in heavy
nuclei collisions is supposed as a promising approach to produce new heavy and
superheavy nuclei, especially neutron-rich nuclei. The investigation of their
properties is very important for understanding of nucleosynthesis processes. To
reach the «island of stability» the use of heavy systems such as 238U + 238U and
238U + 248Cm in MNT reactions [1] are often proposed for synthesis of
neutron-rich transuranium nuclei, which can’t be produced in the complete fusion
reactions with stable ions. Recently the properties of fragments formed in the
136Xe + 238U [3] and 209Bi + 197Au, 208Pb, 232Th, 238U [4] reactions at
energies above the Coulomb barrier have been experimentally investigated in the
Flerov Laboratory of Nuclear Reactions at CORSET setup [2]. Implementing of two
independent experimental techniques, namely, two-arm time-of-flight
measurements to investigate two-body coincidences and three-arm time-of-flight
and energy measurements for three-body coincidences made it possible to explore
the properties of binary fragments, as well as three-body events (projectile-like
fragment (PLF) and sequential fission fragments of heavy MNT fragment). The
cross sections for PLFs along with survived target-like fragments (TLFs) and TLFs
undergoing fission have been obtained. The total excitation energies of the formed
dinuclear systems in MNT reactions have been estimated from the measurements
of total kinetic energies. For the reactions with the 238U target the mass loss
during the deexcitation process of excited PLFs has been found using the
measured primary and secondary masses. The transfers of significant number of
nucleons from the projectile to the target nucleus have been found. The obtained
experimental results and the comparison with theoretical calculations performed
within the multidimensional dynamical model of nucleus-nucleus collisions based
on the Langevin equations [5] are presented.
An overview of the
properties of an effective meson action based on the description of the QCD
vacuum in terms of a mean field corresponding to a statistical ensemble of almost
everywhere homogeneous Abelian (anti-) self-dual gluon fields represented in the
form of domain wall networks is given. Such a mean field ensures the confinement
of static and dynamic quarks and determines the nature of the realization of chiral
symmetry. This approach provides quite coherent formalism for calculation of the
mass spectrum of mesons from pion to upsilonium, studying the effects of strong,
weak and electromagnetic interactions of mesons (decay constants and form
factors). In particular, the role of strong electromagnetic field as a deconfinement
catalyst is highlighted. A brief discussion is given of the relationship of this mean
field approach with the results of the functional renormalization group,
Dyson-Schwinger and Bethe-Salpeter equations, soft wall AdS/QCD models, etc.
The Spin Physics Detector (SPD) at the Nuclotron based Ion Col- lider
fAcility (NICA) is designed to study nucleon spin structure in the three dimensions.
With capabilities to collide polarized protons (up to √s = 27 GeV) and deuterons
(up to √s = 13.5 GeV) with peak design luminosity 10^{32} cm^{−2} s^{−1} for
protons (an order of magnitude less for deuterons), the experiment will allow
measurements of cross-sections and spin asymmetries sensitive to the
un-polarized and various polarized (helicity, Sivers, Boer-Mulders) gluon
distributions inside the nucleons. Proposed asymmetry measurements in three
par- ticular channels (prompt photon, charmonia and open-charm meson
production) and their possible impacts in our present understanding of gluon spin
distributions will be presented.
We analyse the binding energy and charge distribution radius for the
latest superheavy nuclei synthesized in various laboratories, with atomic numbers
$Z=110-118$. For this calculation we use extended Thomas-Fermi approximation
within the relativistic mean field framework. The binding energy and radii are
compared with the results obtained from relativistic Hartree calculations along with
the experimental data, wherever available, to check the reliability of the methods.
The calculations are extended to estimate the giant monopole resonances to
understand the collective vibration of the nucleons for such superheavy nuclei. The
giant monopole resonances obtained from scaling calculations are compared with
the constraint computations. Furthermore, the results are compared with other
known methods, such as the relativistic Random Phase Approximation (RPA) and
time-dependent mean field calculations along with some known lighter nuclei,
specifically Zr isotopes (N=42-86) and O-isotopes (N=10-36). Finally, the nuclear
compressibility of the superheavy nuclei are predicted from the obtained breathing
mode energy.
Exotic nuclei are typically produced via projectile fragmentation or
projectile fission at relativistic energies, or through complete fusion reactions at
near-Coulomb barrier energies. These production methods, along with the
available beam intensities, define the current boundaries of the chart of nuclides.
However, theoretical predictions suggest that several thousand additional isotopes
may exist on the neutron-rich side, including many along the astrophysical
r-process path. Multi-nucleon transfer (MNT) reactions offer a promising pathway
to access this largely unexplored territory. In our recent studies published in ref [1],
we investigated MNT reactions involving the systems 48Ca+208Pb, 50Ti+208Pb,
and 40Ar+209Bi, focusing on the population of nuclei with proton numbers greater
than that of the target. The target-like reaction products were separated in flight
using the velocity filter SHELS of the Flerov Laboratory for Nuclear Reactions
(FLNR), Dubna. Our goal was to examine transfer reactions for producing new
heavy and superheavy nuclei and to assess the applicability of velocity filters for
their investigation. We observed and studied about 40 different nuclides, resulting
from the transfer of up to eight protons from the projectile to the target and moving
in forward direction relative to the beam axis. We present cross-section
systematics for isotopes of elements Z = (83 – 91) measured in our experiment
and compare them with available data from transfer reactions with actinide targets
which lead to isotopes up to Z = 103. Our results will be discussed in the context of
previous measurements, and we will present future prospects for employing MNT
reactions to produce new heavy and superheavy isotopes [1–6]. In addition, the
design of a new kinematic separator, the Separator for Transactinide Research
(STAR), to be developed at FLNR, JINR (Dubna), will be introduced [6–8]. This
project will be carried out alongside the modernization of the U400 cyclotron
(U400R).
References: 1. H.M. Devaraja, A.V. Yeremin, M.L. Chelnokov, V.I.
Chepigin, S. Heinz, et al., Phys. Lett. B 862, (2025) 139353 2. H.M. Devaraja, S.
Heinz, O. Beliuskina, V. Comas, S. Hofmann, et al., Phys. Lett. B 748, (2015)
199–203. 3. H.M. Devaraja, S. Heinz, O. Beliuskina, S. Hofmann, C. Hornung, et
al., Eur. Phys. J. A 55, (2019) 25. 4. H.M. Devaraja, S. Heinz, D. Ackermann, T.
Göbel, F.P. Heßberger, et al., Eur. Phys. J. A 56, (2020) 224. 5. S. Heinz, H.M.
Devaraja, Eur. Phys. J. A 58, (2022) 114. 6. H.M. Devaraja, A.V. Yeremin, S. Heinz
and A.G. Popeko, Phys. Part. Nucl. Lett. 19, (2022) 693- 716 (2022) 7. A. Yeremin,
“Prospects of investigation of multinucleon transfer reactions,” in Proceedings of
the Programme Advisory Committee for Nuclear Physics 51st Meeting, January 30–31, 2020, Dubna, Russia. 8. H.M. Devaraja, A.I. Svirikhin, S. Heinz, A.V. Isaev,
I.N. Izosimov et al., In-flight separation of heavy multinucleon transfer products
using the kinematic separator SHELS, Submitted to Brazilian Journal of Physics on
April 2025
The Multi-Purpose Detector (MPD) experiment at the NICA facility
(JINR, Dubna) will explore the high net-baryon density region of the QCD phase
diagram. Scheduled to begin operation in 2026, it will conduct heavy-ion collisions
at energies of √sNN = 4-11 GeV (collider mode) and √sNN = 2.4-3.5 GeV
(fixed-target mode). Dilepton measurements provide insights into the initial
temperature and lifetime of the fireball. This presentation will focus on the
prospects for dilepton measurements with the MPD apparatus. The details on the
performance of the detector, highlighting its excellent capabilities for track
reconstruction, electron identification, and essential electron-hadron separation will
be provided. Moreover, selected physics feasibility studies will be presented to
demonstrate the potential of these measurements. The report will also include a
current status update on the NICA facility as well as the MPD experiment.
This talk will have two parts. In the first part we will provide a brief overview of the nuclear physics research at TIFR. In the second part we will go little deeper in some of the topics, drawing primarily from the activities of the speaker. Efforts will be made to discuss topics which are of common interests to researcher in TIFR and JINR. Possible scopes of collaborative works will also be discussed.
Inter University Accelerator Centre (IUAC) is an autonomous centre of the University Grants
Commission (UGC), Government of India, providing advanced facilities to the user community for
carrying out accelerator-based research in basic sciences for more than three decades. Experimental
nuclear physics, both nuclear reaction dynamics and nuclear structure, has been a core area of
research since the inception of IUAC. Several state-of-the-art experimental facilities, namely, two
recoil separators (HIRA and HYRA), an array of neutron detectors (NAND), a large scattering chamber
(GPSC) and a large array of HPGe Clover detectors (INGA) etc. are available at IUAC to facilitate
research by the user community. An overview of the facilities and research activities will be
presented with an emphasis on the physics programme pursued with the two recoil separators at
IUAC.
The BM@N is the first woking experiment on the NICA complex (Dubna,
Russia). In the winter of 2022 – 2023 the BM@N experiment performed its first
physics run with full configuration. Over 500 million events of Xe+CsI interactions
with the beam kinetic energy of 3.8A GeV and about 50 million events with energy
3.0A GeV were collected. Since then, there has been an active phase of
processing and analyzing experimental data. The talk will present the latest
physics results obtained by the BM@N collaboration and plans to the upcoming
experimental run.
In this work, we present the first investigation of dark matter-admixed
quarkyonic stars (DAQSs) using a two-fluid framework. The visible sector of the
star is described through a quarkyonic equation of state (EOS) based on the
Effective Relativistic Mean Field (E-RMF) model, while the DM component is
modeled as a degenerate fermionic gas with scalar and vector self-interaction
terms. Our study begins with the mass-radius characteristics, demonstrating that
the addition of DM allows stellar configurations to attain masses consistent with the
GW190814 event. Depending on the EOS, we uncover two possible morphologies:
DM-core dominated and DM-halo dominated stars, each associated with distinct
structural features. By fixing the stellar mass within the GW190814 range, we
constrain the viable DM fractions and assess the impact of different interaction
channels. With the resulting EOSs, we extend our analysis to tidal deformability
and stellar radii, observing compatibility with the constraints from GW170817,
GW190814, and NICER. We then summarize the key properties of DAQSs
covering EOS type, DM content, morphology, and observable quantities-in a
comparative overview. Altogether, this work establishes a coherent two-fluid
description for probing dense QCD matter and DM in the multi-messenger context,
and supports the interpretation of the GW190814 secondary as either a DM-core
or DM-halo quarkyonic star.
The three-flavour framework of neutrino oscillations successfully
explains most experimental results; however, persistent anomalies at both short-
and long-baseline experiments hint at the existence of additional light sterile states.
In particular, eV-scale sterile neutrinos are motivated by LSND and MiniBooNE
results, while sub-eV sterile states have been proposed to address the T2K–NOνA
tension and the absence of the expected solar upturn, respectively. Such sterile
states are singlets under the Standard Model gauge group and mix only through
their admixture with active neutrinos. In this work, we investigate the
phenomenology of the 3 + 2 scenario, incorporating one eV-scale sterile neutrino
together with a sub-eV state, and analyse their impact on absolute-mass related
observables: the sum of neutrino masses constrained by cosmology, the effective
electron neutrino mass from beta decay, and the effective Majorana mass probed
in neutrinoless double beta decay. We demonstrate that the presence of two sterile
states can significantly modify the allowed parameter space compared to the
three-flavour and 3+1 frameworks, with some mass-ordering schemes already
disfavored by current cosmological and laboratory limits. Finally, we assess the
implications of upcoming sensitivities from KATRIN, Project 8, and nEXO,
highlighting the complementary role of sub-eV sterile neutrinos in probing physics
beyond the minimal three-flavor paradigm.
The advent of high-efficiency gamma ray spectrometers with multiple
types of detectors, digital-signal-processing based data acquisition system, and
the realistic possibility of taking a stride in the hitherto unknown territory of nuclear
landscape are driving the low- and medium-energy nuclear physics into the path of
exciting exploration. With this in consideration, a novel facility, DURGA (Dhruva
Utilization in Research using Gamma Array), has recently been developed at
Dhruva reactor (R3001 neutron beam-port), by the Nuclear Physics Division
(NPD), Bhabha Atomic Research Centre (BARC), Mumbai, India. The concept and
possible utilization of the aforesaid facility is very unique in the sense that it is the
only other such large-scale experimental facility in the world, apart from the FIPPS
at Grenoble, France, for carrying out “prompt” γ-ray multi-fold coincidence
spectroscopy using thermal-neutron beam. The hybrid gamma-detector array in
the facility, consisting of eight Compton-suppressed clover Germanium detectors
(32 HPGe segments) and ten LaBr3(Ce) fast scintillators in its present
configuration, is integrated with an in-house developed, state-of-the-art
multi-frequency digitizers-based trigger-less data acquisition system for high data
throughput. With this facility, rich Physics in the realm of neutron-rich radioactive
nuclei as well as low-excitation energy regime of stable nuclei, that have been
hitherto inaccessible through the existing nuclear structure research facilities in
India, can be explored. Apart from Prompt Capture Gamma Spectroscopy (PCGS)
and Prompt Fission Fragment Spectroscopy (PFFS), Decay-Gamma Coincidence
Spectroscopy (DGCS), at times even in combination with the Pneumatic Carrier
Facility (PCF) at Dhruva, has also been one of the major research activities at this
facility. This digital hybrid gamma detector array, when used in combination with
the Pneumatic Carrier Facility (PCF), poses as one of the most powerful setups for
half-life measurements and decay spectroscopy. Nuclei with higher
neutron-to-proton ratios are difficult to study in accelerator-based facilities using
stable projectile and target combinations. One of the means to access and study
the structure/properties of such nuclei is nuclear fission. Thermal neutron induced
fission fragment spectroscopy provides access to these difficult-to-reach nuclei to
study their medium- and high-spin nuclear structures in detail. Additionally, decay
spectroscopy of the neutron-rich fission fragment nuclei is instrumental in
revealing/affirming the decay chain of isotopes and low-spin structures of daughter
nuclei from the primary fission fragments. This facility has now been opened up to he potential users from other Indian institutes and universities. Under the first
ongoing National Experimental Users’ Campaign (since Oct. 2024), sixteen (16)
experiments, with each spanning 5-7 days of round-the-clock beam-time on
average, have been successfully carried out by research groups from institutes
and universities. Data are being analyzed, simultaneously, by the user groups at
their respective places. An overview of this facility, some recent outcomes, nuclear
structure research activities at NPD, BARC, and future possibilities under
collaborative research will be presented during the workshop.
An experimental study to elucidate the fusion fission dynamics from a
series of nuclear reactions with 40Ar beam at near barrier energies have been
carried out at the K500 cyclotron at VECC, Kolkata. The role of the deformed 40Ar
projectile on a series of targets of 206Pb and 208Pb was examined in this study.
The main motivation was to study the competition between quasi-fission and fusion
fission and its evolution with the shell closures in the target nucleus.
The Hoyle state (Ex = 7.654 MeV, Jπ = 0+) in 12C plays a central role in
stellar nucleosynthesis, serving as the resonant gateway for carbon formation
through the triple-alpha process. Despite its well-established sequential decay via
the ground state of 8Be, the rare possibility of direct three-alpha (DD) decay
remains a key probe of its underlying alpha-cluster. In this work, we explore both
the structural and decay aspects of the Hoyle state and its excitations through
combined experimental and theoretical approaches. A detailed 3-body penetrability
calculation based on semiclassical Wenzel–Kramers–Brillouin theory utilizing
hyperspherical coordinates was performed to estimate upper limits on the
direct-decay branching ratios for various three-alpha configurations. Assuming the
observed 2+ state at ~10 MeV to be a collective excitation of the Hoyle state, the
calculated upper limits for the DDφ, DDL, and DDE decay modes are 3.5×10-6,
2×10-7, and 6.7×10-6, respectively, underscoring the strong configuration
dependence of the decay dynamics. A complementary high-precision
measurement employing an array of eight double-sided silicon strip detectors and
advanced kinematic reconstruction techniques yielded over 2.2×10^5 fully
reconstructed Hoyle events. Likelihood analysis using folded Dalitz-plot projection
and fractional energy difference methods established the most stringent
experimental limits to date, with an upper limit of 0.018% for the DDφ mode and
0.002% for DDE mode. Further refinement using a Bayesian soft-assignment
scheme offered a realistic branching ratio of about 0.0018% for DDφ decay, the
lowest achievable through an experiment and the closest so far to the theoretical
predictions. Further, a dedicated search for the predicted Efimov-like 0+ state at
7.458 MeV in 12C revealed an upper limit of 0.014% for its alpha-decay width
relative to the Hoyle state. Penetrability calculations indicate a more extended
spatial configuration for this state, and astrophysical modeling suggests a modest
enhancement in the triple-alpha reaction rate compatible with stellar helium-flash
conditions. Together, these findings provide refined constraints on the cluster
structure and decay dynamics of the Hoyle state, with significant implications for
nuclear structure models and carbon synthesis in stars.
Quantum chromodynamics (QCD) possesses infinitely many degenerate
vacua distinguished by winding numbers with transitions mediated by topological
gauge fields that flip helicities of quark. This induces local P and CP violation and
generates a chirality imbalance, described by a chiral chemical potential. We will
study collective oscillations of partonic degrees of freedom in such a system using
hard thermal loop approximation. The effective propagator derived via the
Schwinger–Dyson approach provides a basis for evaluating observables such as
photon damping, photon emission and dilepton production in chiral QCD matter.
Measurement of electron beam polarization is a cornerstone for
experiments probing hadronic structure and searching for Physics beyond
standard model. Compton polarimetry, based on Compton scattering between
polarized electrons and polarized photons offer non invasive, continuous
monitoring suited for high current, long duration experiments at
facilities like the Thomas Jefferson National Accelerator Facility
(JLab). However the drive for ever greater precision has spurred
significant technical evolution and confronted the scientific community
with new challenges related to systematic uncertainties and
understanding detector responses. Unlike collider experiments, JLab
typically operates at lower beam current (~100 microAmpere), resulting
in longer measurement times and an increased sensitivity to systematic
errors. At lower energies, the asymmetry in scattering becomes smaller,
further complicating the separation of signal from background and the
understanding of any non linearity in detector response.
The latest polarimeter upgrades at JLab includes pixelated diamond based
electron detector, improved trigger mechanism that allows precise
extraction of asymmetry and real time data quality monitoring. This work
reviews these challenges and highlights ongoing adaptations referencing
recent advances achieved at JLab.
Unlike the other reaction mechanisms, nuclear fission process leads to
the production of a large number of fission fragment nuclei. As a result, very
complicated in-beam gamma ray spectra are obtained from the experiment based
on fission fragment spectroscopic measurement. Hence, a very careful and
thorough analysis procedure is to be adopted for extracting different features
related to the underlying fission dynamics. Over the last few years, our group has
performed several fission fragment spectroscopic experiments using the light
actinide targets and large arrays of gamma detectors. The light mass projectiles
associated with the tightly bound as well as loosely bound features were used for
these experiments. Several fascinating physics issues such as the competition
among the different possible fission modes, influence of shell closures in
establishing the different fission modes, competition among the onset of complete
and incomplete fusion-fission processes etc. have been unveiled following the
results obtained from the experiments. All the new findings obtained from the
experiments will be presented. *Help and support received from all the
collaborators during the different phases of the work is deeply appreciated. The
financial assistance received from SERB, Govt. of India (File Number:
CRG/2021/004680), IUAC, New Delhi (Project Code No. UFR 71344), and
UGC-DAE CSR (Project No.: CRS/2021-22/02/472) is gratefully acknowledged.
References: 1. Aniruddha Dey et al., Nucl. Phys. A 1053 (2025) 122962 2. Krishna
Debnath et al., Proceedings of the DAE Symposium on Nuclear Physics, 68 (2024)
375; 68th DAE Symposium on Nuclear Physics held at IIT, Roorkee, India during
December 7 – 11, 2024
The study of nuclear reactions across different energy domains provides
valuable insights into nuclear structure, dynamics, and the equation of state of
nuclear matter. At low energies, reactions are dominated by mean-field effects,
whereas at very high energies, nucleon–nucleon collisions can produce
quark–gluon plasma. In the intermediate energy regime (20 MeV/nucleon to 2
GeV/nucleon), mean-field and nucleon–nucleon collisions compete, and nuclear
multifragmentation emerges as the dominant reaction process [1,2]. Experimental
studies of multifragmentation and nuclear liquid-gas phase transition around the
Fermi energy domain have been pursued for decades at major heavy-ion facilities
worldwide, with significant contributions from JINR, Dubna [3]. In India, such
experimental studies are recently initiated at the K=500 superconducting cyclotron
at VECC, Kolkata [4]. Theoretical models have been developed to understand the
complex reaction mechanism and interpret experimental data, broadly classified
into dynamical [5,6] and statistical [7,8] models. Based on dynamical
(BUU@VECC-McGill) and statistical (CTM) model studies, this presentation
addresses three key topics: (i) The evolution of fragment mass distributions,
including intermediate-mass fragments (IMF) and neutron-rich nuclei, reflecting the
transition from fission at low excitation to multifragmentation at moderate excitation
and eventual breakup into numerous small, neutron-rich fragments at higher
temperatures [9]. (ii) Signatures of the nuclear liquid–gas phase transition [10],
highlighted by the derivative of fragment multiplicity with respect to temperature
[11] as an experimentally accessible observable that is identical to specific heat
behavior and has been recently confirmed experimentally. (iii) Constraints on the
nuclear symmetry energy at sub-saturation densities, derived from isoscaling [4]
and isospin transport studies [12] at Fermi energies, which are highly sensitive to
the density dependence of the symmetry energy and provide critical input to the
nuclear equation of state relevant for nuclear physics and astrophysics.
References: [1] S. Das Gupta, S. Mallik and G. Chaudhuri, “Heavy ion reaction at
intermediate energies: Theoretical Models”, World Scientific Publishers (2019). [2]
Bao-An Li and Wolf-Udo Schroder, Isospin Physics in Heavy-Ion Collisions at
Intermediate Energies, Nova Science Pub. Inc. (2001). [3] V. A. Karnaukhov, H.
Oeschler, S. P. Avdeyev et. al., Nucl. Phys. A 749, 65 (2005) . [4] P. Karmakar, S.
Kundu, T.K. Rana, S. Mallik, S. Manna et. al., Phys. Rev. C 112, 024614 (2025).
[5]G. F. Bertsch and S. Das Gupta, Phys. Rep 160, 189 (1988). [6] J. Aichelin,
Phys. Rep. 202, 233 (1991). [7]J.P. Bondorf, A.S. Botvina, A.S. Iljinov, I.N.Mushustin, K. Sneppen , Phys. Rep. 257, 133(1995). [8] C. B. Das, S. Das Gupta,
W.G. Lynch, A.Z. Mekjian and M.B. Tsang, Phys. Rep. 406, 1 (2005). [9] S. Mallik,
Phys. Rev. C 107, 054605 (2023). [10] B. Borderie and J. D. Frankland, Prog. Part.
Nucl. Phys. 105, 82 (2019). [11] S. Mallik, G. Chaudhuri, P. Das and S. Das Gupta,
Phys. Rev. C 95, 061601 (2017)(R). [12] C. Ciampi, S. Mallik, F. Gulminelli, D.
Gruyer et. al, Phys. Lett. B 868,139815 (2025).
In relativistic heavy-ion collisions, Lorentz contracted pancake-shaped nuclear overlapped region evolves into a rapidly expanding approximately spherically shaped fireball. This shape change, though not topological in nature, influences the expansion dynamics, temperature evolution and lifetime of the medium. These, in turn, affect the rate of QCD topological transitions.
In this work, we employ a simple toy model that links the geometry of the fireball evolution to the rate of topological transitions in the QGP. We use parametric expansion dynamics and Lattice-inspired results for the sphaleron rates to estimate the total topological activity and its sensitivity to geometric parameters. The study aims to offer insights into the possible enhancement or suppression of chirality related observables in heavy-ion collisions.
This is important to study QCD phase diagram using ultra relativistic
heavy ion collisions. The medium created in such a collision is often of dimensions
a few fermi. An understanding of the effect of the finite volume and the boundary is
important for connecting the experimental results to the phase diagram. Using the
Nambu Jona-Lasinio model, an effective theory for the chiral transition of quantum
chromodynamics (QCD), we have studied the effect of the finite volume of the
fireball on the transition line at finite temperature and density using the MIT
boundary condition. to mimic the condition that the system is deconfined inside.
We studied the effect of the finite volume on the transition temperature and on
number density and its susceptibilities.