DAE-BRNS symposium on "Contemporary and Emerging Topics in High Energy Nuclear Physics (CETHENP 2022)"

Variable Energy Cyclotron Centre

Variable Energy Cyclotron Centre

1/AF, Bidhannagar, Kolkata - 700064, West Bengal, India

In this symposium, we plan to bring together theoretical and experimental physicists from around the country to discuss new developments in high energy heavy-ion physics with a focus on the below mentioned topics.  There will be extensive discussions both on theoretical as well as experimental aspects on these selected signals of heavy-ion collisions. A special emphasis will be given to the latest theoretical findings from the analysis of the available data from different experimental facilities and prospect and feasibility of these measurements in the future experiments at high baryon densities.


The topics of discussion are :

  • Electromagnetic probes.
  • Heavy quarks and quarkonia.
  • Jets
  • Strangeness
  • Abhi Modak
  • Abhijit Bhattacharyya
  • Amaresh Jaiswal
  • Aminul Islam Chowdhury
  • Anand Kumar Dubey
  • Ankhi Roy
  • Ankit Kumar Panda
  • Apar Agarwal
  • Argha Deb
  • Arghya Chatterjee
  • Arun Kumar Yadav
  • Ashik Ikbal Sheikh
  • Biswarup Paul
  • Captain Rituraj Singh
  • Chandrasekhar Ghosh
  • Chitrasen Jena
  • Deekshit Kumar
  • Dinesh Srivastava
  • Dushmanta Sahu
  • Gowthama K K
  • Hirak Kumar Koley
  • Jai Prakash
  • Jajati Kesari Nayak
  • Jane Alam
  • Joyati Mondal
  • Krishan Gopal
  • Md Samsul Islam
  • Mitali Mondal
  • Mohd Danish Azmi
  • Monirul Purkait
  • Munshi Golam Mustafa
  • Nachiketa Sarkar
  • Nihar Sahoo
  • Nilanjan Chaudhuri
  • Pallavi Kalikotay
  • Partha Bagchi
  • Partha Pratim Bhaduri
  • Pingal Dasgupta
  • Pooja -
  • Raghunath Pradhan
  • Raghunath Sahoo
  • Rajendra Nath Patra
  • Rajkumar Mondal
  • Ranjita Kumari Mohapatra
  • Ritesh Ghosh
  • Rudrapriya Das
  • Rupa Chatterjee
  • Sabita Das
  • Sabyasachi Ghosh
  • Sanchari Thakur
  • sandeep chatterjee
  • sanjib muhuri
  • Santosh Kumar Das
  • Saumen Datta
  • sayak chatterjee
  • Sidharth Kumar Prasad
  • Sinjini Chandra
  • Snigdha Ghosh
  • Somenath Pal
  • Somnath Kar
  • Sourav Sarkar
  • Sourendu Gupta
  • Subash Chandra Behera
  • Subhasis Chattopadhyay
  • Subikash Choudhury
  • Sudhir Pandurang Rode
  • Sudipan De
  • Sumit Kumar Kundu
  • Sumit Kumar Saha
  • Sumit Som
  • Sunny Singh
  • Surasree Mazumder
  • Sushant Kumar Singh
  • Swapnesh Khade
  • Tinku Sinha Sarkar
  • Tribhuban Parida
  • Utsab Gangopadhyay
  • Vivek Kumar Singh
  • Wadut Shaikh
  • Zubayer Ahammed
    • 09:00 09:30
      Registration VECC Main Gate

      VECC Main Gate

    • 09:30 10:45
      Day 1: Session 1 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Abhijit Bhattacharyya (Department of Physics, University of Calcutta)
      • 09:30
        Director's address 10m
        Speaker: Dr Sumit Som (VECC, Kolkata)
      • 09:40
        Introduction 10m
        Speaker: Dr Subhasis Chattopadhyay
      • 09:50
        Vote of thanks 10m
        Speaker: Sanjib Muhuri (VECC)
      • 10:00
        Relativistic heavy-ion collisions: The Big Picture 45m
        Speaker: Prof. Sourendu Gupta (TIFR, Mumbai)
    • 10:45 11:15
      Tea Break 30m
    • 11:15 13:05
      Day 1: Session 2 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Dr Subhasis Chattopadhyay
      • 11:15
        Measurements of Electromagnetic and Hard probes at RHIC 30m
        Speaker: Dr Nihar Ranjan Sahoo (NISER, Bhubaneswar)
      • 11:45
        Quantum Field Theoretical structure of conductivity and di-lepton 30m
        Speaker: Dr Sabyasachi Ghosh (IIT Bhilai)
      • 12:15
        Di-lepton polarization and anisotropy in relativistic heavy-ion collisions 30m
        Speaker: Dr Amaresh Jaiswal
      • 12:45
        Measurement of exclusive vector meson photoproduction in ultra-peripheral pPb and PbPb collisions with the CMS experiment 20m

        The exclusive photoproduction of vector mesons provides a unique opportunity to constrain the gluon distribution function within protons and nuclei. Measuring vector mesons of various masses over a wide range of rapidity and as a function of transverse momentum provides important information on the evolution of the gluon distribution within nuclei. A variety of measurements, including the exclusive J/$\psi$, $\rho$, and $\Upsilon$ meson production in pPb (at nucleon-nucleon center of mass energies of 5.02 and 8.16 TeV) and PbPb (5.02 TeV) collisions, will be presented as a function of squared transverse momentum and the photon-proton center of mass energy. Finally, compilations of these data and previous measurements are compared to various theoretical predictions.

        Speaker: Mr Subash Chandra Behera (Indian Institute of Technology Madras (IN))
    • 13:05 14:30
      Lunch 1h 25m VECC VIP Lounge

      VECC VIP Lounge

    • 14:30 16:00
      Day 1: Session 3 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Sidharth Kumar Prasad (Bose Institute)
      • 14:30
        Dimuon measurement at CBM experiment 20m

        The Compressed Baryonic Matter (CBM), currently under construction at the Facility for Anti-proton and Ion Research (FAIR) accelerator complex in Darmstadt, Germany aims to explore the QCD phase diagram at high baryon densities. Till date, no dilepton data have been collected in heavy-ion collisions at beam energies between 2A and 40A GeV. CBM aims to perform pioneering measurements of lepton pairs in nuclear collisions, employing both electron ($e^{+}e^{-}$) and muon ($\mu^{+}\mu^{-}$) channels, in the energy domain $\sqrt{s_{NN}}\sim$ 2.7-4.9 GeV, using unprecedented reaction rates of up to 10 MHz. The Muon Chamber (MuCh) sub-system is dedicatedly designed to track the muons pairs coming from the decay of Low Mass Vector Mesons (LMVM) and $J/\psi$. The expected performance in the muon channel is compared in terms of signal significances and background components for nucleus-nucleus (NN) and hadron-nucleus (pN) collisions.

        In this contribution, the details of the simulation framework, analysis techniques and results will be presented for the foreseen CBM energies.

        Speaker: Mr sayak chatterjee (Bose Institute)
      • 14:50
        Impact of Baryon anti-Baryon annihilation on apparent strangeness enhancement of Λ̄/p̄ in heavy ion collisions at SPS energy 20m Ajay Divatia Lecture Hall

        Ajay Divatia Lecture Hall

        Speaker: Ekata Nandy (VECC, Kolkata)
      • 15:10
        The anisotropic flow of thermal photons in most-central α-clustered C+Au collisions at 200A GeV 20m

        The light nuclei such as B, C, O etc. can occur in different stable α-clustered states, as found in the low-energy nuclear structure studies. Recent phenomenological findings suggest that such light nuclei with different exotic shapes can produce large initial-state anisotropies in relativistic nuclear collisions. The electromagnetic radiations, being sensitive to the initial dynamics, are expected to be affected by the initial clustered structures significantly. In this work, we estimate the production and anisotropic flow of photons from most-central collisions of triangular α- clustered carbon and gold at $\sqrt{s_{NN}}=$200 GeV at RHIC using an event-by-event hydrodynamic framework and compare the results with those obtained from unclustered carbon and gold collisions. We find that the thermal photon $v_3$ for most central collisions is significantly large for the clustered case compared to the case with unclustered carbon. In contrast, the elliptic flow parameter ($v_2$) is found to be similar for the two cases. We show that the ratio of anisotropic flow coefficients can be a potential observable to detect the α-clustered structure in the carbon nucleus.

        Speaker: Dr Pingal Dasgupta (Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University)
      • 15:30
        Di-lepton production from a hot and dense rotating and magnetized QCD medium 30m
        Speaker: Dr Aminul Islam Chowdhury
    • 16:00 16:30
      Tea Break 30m Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

    • 16:30 17:45
      Day 1: Session 4 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Prof. Saumen Datta (TIFR, Mumbai)
    • 09:30 11:10
      Day 2: Session 1 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Jane Alam (VECC,1/AF Bidhan Nagar, Kolkata)
      • 09:30
        Dilepton production from magnetized quark matter 20m Ajay Divatia Lecture Hall

        Ajay Divatia Lecture Hall

        Speaker: Nilanjan Chaudhuri (Variable Energy Cyclotron Centre)
      • 09:50
        Theoretical overview of quarkonia as a probe of deconfinement 30m
        Speaker: Prof. Saumen Datta (TIFR, Mumbai)
      • 10:20
        Heavy quark dynamics in QCD matter 30m
        Speaker: Dr Santosh Das (IIT Goa)
      • 10:50
        Diffusion of heavy quarks in the early stages of high energy nuclear collisions 20m

        In the pre-equilibrium stage of relativistic heavy-ion collisions, strong quasi-classical gluon fields emerge. These dense, coherent, colored electric and magnetic fields are known as Glasma. Glasma fields evolve, and the lifetime of these strong fields is of the order of the formation and thermalization time of the QGP, typically a short fraction of fm/c. Heavy quarks (HQs) are good probes to study these early stages of high-energy collisions. We aim to study the diffusion of heavy quarks in the evolving Glasma (EvGlasma). Also, we perform a systematic comparison of the diffusion of HQs in the evolving Glasma fields with that of the Markovian-Brownian motion in a thermalized medium of gluons. We observe the superdiffusion of HQs in the EvGlasma fields as the transverse momentum broadening, $\sigma_p$ of HQs increases non-linearly during the very early time. We also find that for a smaller value of saturation scale, $Q_s$, the average transverse momentum broadening is approximately the same for the two cases, but for a larger value of $Q_s$, Langevin dynamics underestimates the $\sigma_p$.

        Speaker: Ms Pooja - (Indian Institute of Technology Goa)
    • 11:10 11:40
      Tea Break 30m Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

    • 11:40 13:00
      Day 2: Session 2 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Prof. Sourav Sarkar (Variable Energy Cyclotron Centre)
      • 11:40
        The impact of memory on heavy quarks dynamics in hot QCD medium. 20m

        Heavy quarks (HQs) are considered as effective probes to study the evolution of the quark-gluon plasma (QGP). We study the dynamics of HQs in a hot QCD medium with a time-correlated noise, η. We have introduced the effect of memory through η and the dissipative force in the Generalized Langevin equation (GLV). We assume that the time correlations of the colored noise decay exponentially with time, called the memory time, \tau. We have explored the effect of non-zero values of \tau on the nuclear modification factor, R AA, and transverse momentum broadening, \sigma_p of the HQs within the QGP medium. We find that overall memory slows down the momentum evolution of heavy quarks; In fact, transverse momentum broadening and the formation of RAA are slowed down by memory and the thermalization time of the heavy quarks becomes larger. We will discuss the potential impact on other observables.

        Speaker: Mr Jai Prakash
      • 12:00
        Recent results on bottomonium production from the LHC 30m
        Speaker: Dr Subikash Choudhury (SINP, Kolkata)
      • 12:30
        Quarkonia production in ultra-peripheral collisions at RHIC 30m
        Speaker: Dr Ashik Ikbal
    • 13:00 14:30
      Lunch 1h 30m VECC VIP Lounge

      VECC VIP Lounge

    • 14:30 16:00
      Day 2: Session 3 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Munshi Golam Mustafa (Saha Institute of Nuclear Physics, Theory Division, 1/AF Bidhan Nagar, Kolkata 700064)
      • 14:30
        Experimental status on charmonium production at LHC 30m
        Speaker: Dr Biswarup Paul
      • 15:00
        Diffusion of Heavy Quark in a hot and magnetic Quark Gluon Plasma-perturbative vs non perturbative 20m

        The recent studies have indicated an existence of a strong magnetic field in non central Heavy Ion Collisions(HICs). Though strong to begin with the field decays fast. It is still possible for the magnetic field to exist in the thermalised Quark Gluon Plasma(QGP) depending on the electrical conductivity of the medium. If a significant amount of magnetic field is present in the medium, it will affect various aspects. We have calculated different diffusion coefficients of Heavy Quark(HQ), a very good probe of QGP, in presence of a strong magnetic field inside a hot QGP in some of our recent works. It is well established that perturbative QCD description is not enough in order to explain certain experimental observations at the low to intermediate $p_T$ region of HQ and at temperatures close to the critical temperature. There are various studies approaching the non-perturbative calculation from various vantage points within the framework of perturbative QCD, like T-matrix and potential approach.
        In this present work, we have considered the complex HQ potential in presence of a strong magnetic field in a hot QGP and posed it as effective gluon propagator. The part of the potential which is Yukawa type is responsible for the perturbative and the string part is responsible for the non-perturbative contribution. We calculate the scattering rate of HQ interacting elastically with the medium light quarks/anti-quarks and gluons.and consequently, estimate the various diffusion coefficients for two cases: 1) HQ velocity is along the direction of the magnetic field and 2) HQ velocity in the perpendicular direction to the magnetic field.
        We have compared the perturbative diffusion coefficients with their non-perturbative counterparts in presence of a strong magnetic field for the first time. Though the perturbative contribution is always dominant over that due to non-perturbative, the difference between those two is lower at lower temperatures rendering the non-perturbative estimation more important at the lower temperatures. At higher temperatures, the asymptotic freedom enhances perturbative contribution while the lower value of string tension (taken from finite temperature lattice calculations) or confinement reduces non-pertubative effect. All these might have profound effect on various experimental observations.

        Speaker: Surasree Mazumder (Indian Institute of Technology Gandhinagar)
      • 15:20
        Do quarkonia thermalize at the LHC? 20m

        We analyze the relative yields of different bottomonia and charmonia states produced in Pb+Pb collisions at LHC, within an ideal hadron resonance gas framework. The underlying assumption is the early thermalization and subsequent freezeout of these heavy hadrons resulting in their chemical freezeout at a temperature, significantly higher than that of light and strange hadrons. The systematic dependence of the freezeout temperature on the collision energy and centrality is investigated in detail.

        Speaker: Nachiketa Sarkar (National Institute of Science Education and Research)
      • 15:40
        Heavy quark diffusion coefficient in the light of Gribov-Zwanziger action 20m

        As a result relativistic heavy ion collision in Large Hadron Collider(LHC) at CERN and Relativistic Heavy Ion Collider(RHIC), at Brookhaven National Laboratory(BNL),the constituent of those, namely Quarks and Gluons deconfined for a short amount of time, and its internal(color) degrees of freedom governs its dynamics. The deconfinement of the nuclear matter happens at bizzare temperature of ∼ 150 MeV which results in the emergence of a new state of matter, identified as Quark Gluon Plasma(QGP). A well-established result that deconfined matter is not a free gas of quarks and gluons but rather strongly interacting and correlated system signals to incorporate dissipative hydrodynamics as a tool to extract the properties of this extremely dense matter, QGP, in the form of various transport coefficients. Due to the rapid thermalization of the produced particles as a result of collision, characterizing the plasma state of matter based on the information provided in the final stage becomes a head scratching task.
        Heavy quarks are produced in the pre-equilibrium phase i.e. before the formation of QGP. The long relaxation time of heavy quark make it an apt tool to diagnose QGP.
        The study of quarks and gluons falls under perturbative QCD as well as non-
        perturbative QCD. While the perturbative QCD has been well developed, the
        analytical and numerical solution of non-perturbative QCD has still a long way to go. One of the non-perturbative approaches that seem quite promising in the non-perturbative scale is given by Gribov, which later was updated by Zwanziger by formulating renormalizable action at finite temperature, termed as Gribov-Zwanziger(GZ) action. Within the GZ action, the gluon propagator in covariant gauge is expressed as:
        $$D^{\mu\nu}(P)=\left[\delta^{\mu\nu}-(1-\xi)\frac {P^{\mu}P^{\nu}}{P^2}\right]\left(\frac{P^2}{P^4+\gamma_G^4}\right)~,$$ where $\xi$ is the gauge parameter and $\gamma_G$ is termed as the Gribov parameter, which is fixed either by matching the thermodynamic quantities with lattice equation of state or by solving one loop gap equation. I calculated the diffusion coefficient of heavy quark(in gluonic medium) under Gribov prescription and match it with lattice data available in the range $1 \le (T/T_c)\le 5$. We noticed that it has a good agreement with the lattice data.

        Speaker: Mr Sadaf Madni (National Institute of Science Education and Research)
    • 16:00 16:30
      Tea Break 30m Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

    • 16:30 18:20
      Day 2: Session 4 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Zubayer Ahammed (VECC)
      • 16:30
        Re-visiting the $J/\Psi$ suppression for quark-gluon plasma formation in small systems 20m

        There have been different proposals for signatures of the formation of a deconfined thermal medium(quark-gluon plasma) in heavy-ion collisions. The suppression of $J/\Psi$ in the deconfined medium is one of the cleanest signals among many other signatures like elliptic flow, jet quenching etc. However, there are very few signals effective for the formation of QGP in small systems such as the systems produced in proton-proton, proton-deuteron and deuteron-deuteron collisions. Here the medium formed is shown to be very short-lived compared to that formed in heavy ion collision as the system undergoes 3-dimensional spherical expansion from the very beginning of the hydrodynamic phase. We model the small systems for different values of sizes of the system after the Gubser flow solution and we infer that the expansion phase is smaller by a factor of at least 2. We then calculate the dissociation probability of $J/\Psi$ through the non-adiabatic evolution of the state using the time-dependent perturbation theory for different values of thermalization time. We find no significant dissociation of J/Psi in small systems in contrast to the systems produced in Au-Au/Pb-Pb collisions, thereby establishing that quarkonia($J/\Psi$) suppression may not be a successful signature for the formation of the thermal medium for proton-proton/proton-deuteron or deuteron-deuteron collisions.

        Speaker: Partha Bagchi (Tsinghua University, Beijing)
      • 16:50
        Possible Charmonia suppression in high-multiplicity proton-proton collisions at the LHC energies 20m

        Proton–proton ( pp) collision has been considered a baseline to understand the formation of the primordial matter, the quark-gluon plasma in relativistic heavy-ion (AA) collisions. However, recent experimental findings show QGP-like phenomena in ultra-relativistic (TeV) pp collisions. Such findings require a cautious study of the system produced in pp collisions at relativistic energies. In this work, we investigate the charmonium production in pp collisions at $\sqrt{s} $= 5.02, 7 and 13 TeV energies. Further, we obtain net charmonia yield at various event multiplicities using our UMQS model, which includes color screening, gluonic dissociation, collisional damping, and regeneration mechanisms. Using the UMQS model, we try to explain the normalized $J/\psi$ yield against the normalized charged multiplicity and compare it with the data available for 7 and 13 TeV pp collisions. Here we obtain a net suppression of charmonia at high-multiplicity events, indicating the possible existence of quark-gluon plasma in pp collisions. Details of the model ingredients, method of analysis, and important results will be discussed.

        Speaker: Captain Rituraj Singh (Birla Institute of Technology and Science, Pilani)
      • 17:10
        Possibility of a QCD medium formation in LHC proton-proton collisions using light and heavy flavors: A Color String Percolation Approach 20m

        Recent findings of strangeness enhancement and ridge-like structures in pp collisions at the Large Hadron Collider (LHC) have captured much of the scientific interest in the search for QGP-droplets in pp high-multiplicity events. Thus, it is crucial to gather substantial evidence in this new direction. Studying various thermodynamic and transport properties of the matter formed at LHC can give us hints regarding a possible change in dynamics in the systems. We have used the Color String Percolation Model (CSPM), a Quantum Chromodynamics (QCD) inspired theoretical model, to explore this further. The jet quenching parameter (q ̂) has been estimated within the CSPM approach for pp collisions at √s = 5.02 and 13 TeV, Xe-Xe collisions at √(s_NN ) = 5.44 TeV, Pb-Pb collisions at √(s_NN ) = 2.76 and 5.02 TeV. The findings hint at QGP-like medium formation in high-multiplicity pp collisions. In addition, we have also explored the diffusion of charm quark in the deconfined medium with CSPM and estimated the momentum and spatial diffusion coefficients. Finally, we have compared our results with those obtained from various models, such as lattice-QCD. We found that our results reasonably agree with lattice-QCD and other established models, while revealing a hint for QCD medium formation in pp collisions after a threshold in final state multiplicity density.

        Speaker: Dushmanta Sahu (Indian Institute of Technology Indore (IN))
      • 17:30
        Heavy quark diffusion in presence of magnetic field 20m

        In presence of magnetic field the transport coefficients of heavy quarks are seen to have a multi-component structure due to which the spatial diffusion splits into
        longitudinal and transverse components relative to the direction of magnetic field. Owing to the Einstein's relation, the spatial diffusion is expressed as a ratio of electrical conductivity and susceptibility. The anisotropic property of the spatial diffusion comes in due to the multi-component structure of the electrical conductivity tensor in presence of magnetic field. The results are studied as a function of temperature and magnetic field for D mesons and charm quarks for their relevant temperature ranges.

        Speaker: Mr Sarthak Satapathy ( Dinabandhu Mahavidyalaya, Bongaon, North Paraganas - 743235, West Bengal, India)
      • 17:50
        Jet measurements at LHC 30m
        Speaker: Dr Sidharth Prasad (Bose Institute, Kolkata)
    • 09:30 10:50
      Day 3: Session 1 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Chitrasen Jena (Indian Institute of Science Education and Research (IISER) Tirupati)
      • 09:30
        Heavy quarkonia at finite temperature and magnetic field 20m

        Several heavy-ion collision experiments at RHIC and LHC have been performed in identifying quark-gluon plasma (QGP) matter. In recent times, non-central heavy-ion collisions are of more interests where very strong magnetic field is produced in the direction perpendicular to the reaction plane. Many theoretical efforts have been made to study the modification of the strongly interacting matter in presence of an external magnetic field.

        The heavy quarkonium is one of the important probes to investigate the properties of nuclear matter in presence of finite temperature and magnetic field. Also the time scale of quarkonia formation and the magnetic field generation are of similar order. So the study of heavy quarkonia in presence of magnetic field is of great interest.
        In this work we have explored the imaginary part of the Heavy Quark (HQ) potential and subsequently the dissociation of heavy quarkonia at finite temperature and magnetic field. With respect to earlier investigations on this topic, present work contain three new ingredients. First one is considering all Landau level summation, for which present work can be applicable in entire magnetic field domain - from weak to strong. Second one is the general structure of the gauge boson propagator in a hot magnetized medium, which is used here in heavy quark potential problem first time. Third one is a rich anisotropic structure of the complex heavy quark potential, which explicitly depends on the longitudinal and transverse distance. By comparing with earlier references, we have attempted to display our new contributions by plotting heavy quark potential tomography and dissociation probability at finite temperature and magnetic field.

        Speaker: Ritesh Ghosh
      • 09:50
        Production of Heavy Flavour Decay Muons using Angantyr Model in PYTHIA8 at LHC energies 20m

        In high energy nucleon-nucleon and heavy-ion (HI) collisions, the heavy quarks (charm and beauty) are produced at the very early stages of the collisions due to their large masses ($m_{c}\approx$ 1.29 GeV/$\it{c}^{2}$ and $m_{b}\approx$ 4.19 GeV/$\it{c}^{2}$). These heavy quark productions are mainly from hard parton-parton scattering with large momentum transfer ($Q^{2}$). The heavy quarks are produced much before the formation of the deconfined state of quarks and gluons called Quark-Gluon Plasma (QGP) at extremely high temperature and/or energy density in ultra-relativistic HI collision. After the production of heavy-quarks, they interact and pass through the QGP medium and hence experience a full evolution of the medium formed in HI collisions. Hence, the measurement of heavy quarks is very important probe to study the properties of QGP in HI collisions and provide a stringent test of perturbative QCD (pQCD) calculation over a wide range of transverse momentum ($p_{T}$). The measurement of heavy quarks in pp collisions serve as a baseline study for the same measurement in HI collisions.

        After the discovery of the features of HI collisions such as ridge like effect and strangeness enhancement in high multiplicity pp events at LHC, the physics community started to look for any thermalised medium formation even in small colliding systems. Traditionally, any thermalised medium is not expected to be formed in small systems like proton-proton (pp) and proton-ion (pA) collisions. Here we would like to present the study of Heavy Flavour decay Muons (HFM) at forward rapidity ($2.5

        Speaker: Mr Md Samsul Islam (Saha Institute of Nuclear Physics (IN))
      • 10:10
        Investigating jet modification in high multiplicity proton-proton collisions at 13 TeV using PYTHIA 8 event generator 20m

        We will present a study of multiplicity dependence of the differential jet shape observable $\rho(r)$ in proton-proton (pp) collisions at $\sqrt{s}$ = 13 TeV using PYTHIA 8 Monash 2013 Monte Carlo simulation. A significant modification of $\rho(r)$ is observed in high multiplicity pp collisions compared to the minimum bias ones. We will discuss the underlying physics mechanisms in PYTHIA 8, responsible for the observed modification.

      • 10:30
        Strange productions through transport approach at colliding energy 54.4 GeV/A 20m Ajay Divatia Lecture Hall

        Ajay Divatia Lecture Hall

        Speaker: Apar Agarwal (Variable Energy Cyclotron Centre)
    • 10:50 11:30
      Tea Break 40m Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

    • 11:30 12:15
      Day 3: Session 2 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: JAJATI K. NAYAK (Variable Energy Cyclotron Centre)
      • 11:30
        Constraining the initial baryon profile from baryon and anti-baryon directed flow split 20m

        The origin of rapidity odd directed flow($v_1$) has been understood as a response of the asymmetric distribution of energy and net-baryon density present in the medium at the initial stages of heavy ion collisions. So, the observed splitting of directed flow between baryon and anti-baryon in RHIC BES could be a useful observable to constrain the initial net-baryon profile by model to data comparison. This in turn can enhance our understanding about the mechanism of baryon stopping. In this context, we have proposed an initial condition model of net-baryon and matter deposition which is taken as an input for a multi stage hybrid framework of hydrodynamics evolution and late stage hadronic interaction. In the model calculations we are able to describe the measured splitting of directed flow between baryons($p,\Lambda$) and anti-baryons($\bar{p}, \bar{\Lambda}$) along with $v_1$ of mesons like $\pi^{\pm}, K^{\pm}$ and $\phi$. Even though we have not considered the evolution of other two conserved charges(corresponding to strangeness and electric charge) in our model, still the splitting of $v_1$ between strange and anti-strange particles have been observed at lower collision energies. This effect has been attributed to the employed equation of state which possesses the constraints of strangeness neutrality($n_S=0$) and net electric charge density $n_Q=0.4 n_B$. We will systematically present the model calculations of rapidity, centrality and $p_T$ dependency of measured identified or charged particle's $v_1$ at $\sqrt{s_{NN}} = $ 7.7 GeV to 200 GeV and compare those with experimental data. With the observations from our model calculations, we will explicitly demonstrate the importance to include the conserved charges evolution along with energy density in hydrodynamics simulations of heavy ion collisions.

        Speaker: Mr Tribhuban Parida (IISER Berhampur)
      • 11:50
        Strange particles femtoscopy in PbPb collisions with CMS detector 20m

        The two-particle correlations as a function of relative momenta of identified hadrons involving $\mathrm{K^{0}_{S}}$ and $\Lambda/\bar{\Lambda}$ are measured in PbPb collision at $\sqrt{s_{_{\mathrm{NN}}}} =$ 5.02 TeV with the data samples collected by the CMS experiment at the LHC. Such correlations are sensitive to quantum statistics and possible final state interactions between the particles. The shape of the correlation function is observed to vary largely for different particle pairs, revealing the effect of the strong final state interaction in each case. The source radii are extracted from $\mathrm{K^{0}_{S}K^{0}_{S}}$ correlations in different centrality regions and found to decrease from central to peripheral collisions. The strong interaction scattering parameters are extracted from $\mathrm{K^{0}_{S}K^{0}_{S}}$, $\Lambda\mathrm{K^{0}_{S}}\oplus\bar{\Lambda}\mathrm{K^{0}_{S}}$, $\Lambda\Lambda\oplus\bar{\Lambda}\bar{\Lambda}$ and $\Lambda\bar{\Lambda}$ correlations using the Lednicky-Lyuboshits model, and compared with other experimental and theoretical results. The scattering parameters indicate that the $\Lambda\Lambda\oplus\bar{\Lambda}\bar{\Lambda}$ is attractive and that the $\Lambda\mathrm{K^{0}_{S}}\oplus\bar{\Lambda}\mathrm{K^{0}_{S}}$ interaction is repulsive.

        Speaker: Raghunath Pradhan (Indian Institute of Technology Madras (IN))
    • 12:15 13:15
      Poster session 1h Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

    • 13:15 14:30
      Lunch 1h 15m VECC VIP Lounge

      VECC VIP Lounge

    • 14:30 16:00
      Day 3: Session 3 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Tinku Sinha (Saha Institute of Nuclear Physics, Kolkata)
      • 14:30
        Search for the QCD critical point 30m Ajay Divatia Lecture Hall

        Ajay Divatia Lecture Hall

        Speaker: Jane Alam (VECC,1/AF Bidhan Nagar, Kolkata)
      • 15:00
        Study of particle production mechanism in Au+Au collisions at BES energies using A Multiphase Transport Model 20m

        A Multi-Phase Transport (AMPT) model has been used extensively to study the dynamics of relativistic heavy-ion collisions at various collision energies. The AMPT model is very sensitive to input parameters; therefore, the choice of these parameters are very important to explain the results from various experiments. The motivation of this study is to find the most suitable input parameters for AMPT model that explains the particle production and bulk properties of the medium formed at various BES energies at RHIC.

        In this talk, we will present the $p_{T}$-spectra of identified hadrons ($\pi^{\pm}, K^{\pm},p(\bar{p}),K_{s}^{0}, \Lambda(\bar{\Lambda}$) and $\phi$) in Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7-200 GeV obtained from AMPT model and compare it with the available experimental results. We will also present the centrality and energy dependence of particle yields (dN/dy), average transverse momentum ($\langle p_{T} \rangle$), particle ratios, and compare them with experimental data.

        Speaker: Krishan Gopal (Indian Institute of Science Education and Research Tirupati)
      • 15:20
        Strange particle production in hybrid UrQMD model for various particlization scenarios 20m

        The finite baryon density region of QCD phase diagram, conditions which exists inside the core of neutron stars will be explored by upcoming experiments such as CBM and MPD at FAIR and NICA facilities. As one of the key observables, production of strange particles provides insights about the medium expected to be created in the heavy-ion collisions at beam energies spanning this regime. For the optimal utilization of these future facilities, the predictions from various phenomenological and simulation models are essential. In this presentation, we will report the results from study of strange particle production using hybrid UrQMD model employed with different freeze-out prescriptions available.

        Speaker: Sumit Kumar Kundu (Ph.D. Scholar)
      • 15:40
        Production of Strange Hadrons and Resonances in pp, pPb and PbPb Collisions at the LHC Energies 20m

        Nuclear matter at sufficiently high temperature and energy density undergoes a transition to a phase in which quarks and gluons do not remain confined: the quark-gluon plasma (QGP) phase [1]. Such an exotic state of strongly interacting quantum chromodynamics matter can be produced in the laboratory in high-energy heavy-ion collisions, where an enhanced production of strange hadrons is observed. Strangeness enhancement is originally proposed as a key signature to identify the formation of QGP in high-energy heavy-ion collisions [2]. The yield of strange hadrons is one of the various observables, which is sensitive to the system evolved after nuclear collisions. In particular, the resonance particles are also important for probing QGP phase because of their shorter lifetime (a few fm/c), comparable to the medium lifetime, and due to the rescattering and regeneration processes at the freeze-outs, the yields of the resonances may vary with respect to the non-resonance particles. Recent studies of small collision systems at the Large Hadron Collider (LHC) show unambiguous similarities in hadron production between high multiplicity pp, pPb collisions and PbPb collisions [3]. The studies on production of strange hadron and resonances play important roles in characterizing the LHC data in different collision systems.

        In this contribution, we investigate the strange hadron and resonance yields using pQCD-inspired multiple-Parton scattering approach-based two different models, EPOS3 including the hydrodynamical evolution of produced particles and AMPT with a String Melting scenario. The results of yield ratios of identified hadrons will be presented for pp, pPb and PbPb collisions at various LHC energies and results will be confronted to the available experimental data to understand the properties of strongly interacting matter produced in heavy-ion collisions in terms of the model parameters.

        1. Shuryak E. V., Quantum chromodynamics and the theory of superdense matter, Phys. Rep. 61, 71–158 (1980).
        2. Koch P., Muller B. & Rafelski J., Strangeness in relativistic heavy ion collisions, Phys. Rep. 142, 167–262 (1986).
        3. Adam J. et. al., ALICE Collaboration, Enhanced production of multi-strange hadrons in high-multiplicity proton-proton collisions, Nature Physics volume 13, 535-539 (2017).
        Speaker: Mr Hirak Kumar Koley (Nuclear and Particle Physics Research Centre, Department of Physics, Jadavpur University, Kolkata - 700032, India)
    • 16:00 17:10
      Day 3: Session 4 Ajay Divatia Lecture Hall, VECC

      Ajay Divatia Lecture Hall, VECC

      Convener: Anand Dubey (VECC)
    • 17:10 17:30
      Tea Break 20m Ajay Divatia Lecture Hall

      Ajay Divatia Lecture Hall

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