arXiv subjects

Arpit Singh

Publications and source records attributed to Arpit Singh.

8 recordsLinked to original sources

arXiv2025

Deciphering the dynamics of nuclear collisions with elongated structure of $^{20}$Ne

We investigate the role of intrinsic nuclear geometry of $^{20}$Ne nucleus in particle production in small collision systems. Discrete geometrical representations of $^{20}$Ne, including bi-pyramidal $\alpha$-cluster structure in two different configurations along with NLEFT configurations, are implemented within the Monte Carlo Pythia8/Angantyr framework. The resulting particle production observables in $^{20}$Ne-$^{20}$Ne collisions at $\sqrt{s_{NN}}$ = 5.36 TeV are systematically compared with those obtained using conventional Woods-Saxon description as well as with the available hydrodynamic model calculations. We investigate the sensitivity of charged particle multiplicity, transverse momentum distributions and mean transverse momentum $\langle p_T \rangle$ to nuclear geometry, $\alpha$-clustering, and orientation effects of $^{20}$Ne nucleus. While explicit clustering and orientation dependence lead to a noticeable modifications in final state charged particle multiplicity, their impact on transverse momentum spectra and $\langle p_T \rangle$ remain modest in central collisions. The results highlight the role of intrinsic nuclear geometry and specific orientation of the colliding nuclei, providing insight into the dynamics of small systems in non-hydrodynamic particle production framework.

nucl-th↗

arXiv2025

Simulation-based performance comparison of varied pitch sizes GEM detectors

Gas Electron Multiplier (GEM) detectors, typically featuring a standard pitch size of 140 $\mu$m and an inner hole diameter of 50 $\mu$m, are extensively utilized in high-energy physics experiments for tracking, triggering, and timing measurements. Their characteristics, such as high gain, good position resolution, improved temporal resolution, low discharge probability, radiation hardness, and high rate capabilities, make them highly favoured. Recent experimental studies have shown that triple-GEM detectors with a reduced pitch size of 90 $\mu$m and a smaller hole diameter of 40 $\mu$m can perform better than standard-pitch GEM detectors. To assess the effectiveness of these reduced dimensions, we conducted a simulation-based study using ANSYS and Garfield++. As a first step, we validated the simulation framework by modelling a standard single GEM detector and comparing the results with previous simulations and experimental data. Following validation, we designed GEM structures with reduced pitch sizes of 90 $\mu$m and 60 $\mu$m. We then performed a comparative analysis, focusing on key performance parameters like effective gain, electron transparency, and position resolution. These parameters were varied against an increase in GEM potential, drift electric field, induction electric field, drift gap, induction gap, and gas composition to optimize the performance of the detectors.

hep-ex↗

arXiv2025

Effect of $\alpha$-clusters on particle production in O$-$O and p$-$O collisions at LHC energies

In the present work, O$-$O collisions at $\sqrt{s_{NN}}$ = 7 TeV and p$-$O collisions at $\sqrt{s_{NN}}$ = 9.9 TeV are studied using PYTHIA8/Angantyr model for heavy-ion collisions. The theoretically predicted $\alpha$-cluster structure of oxygen nucleus is implemented in the model to investigate the effect of initial configuration of oxygen nucleus on final state observables. The results obtained from $\alpha$-cluster structure are compared with those obtained from Woods-Saxon nuclear charge density distribution. The Angantyr model simulation showed that the radial distribution of oxygen nucleus in $\alpha$-cluster configuration is more compact in comparison to the Woods-Saxon distribution. The results on charged and identified particle pseudorapidity distribution is obtained in the two initial state configuration of the oxygen nucleus. The results demonstrated that the effect of initial geometrical configuration is more distinct in the non-central collisions in comparison to the central collisions for both O$-$O and p$-$O collisions.

hep-ph↗

arXiv2023

Higher flow harmonics of strange hadrons in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV with HYDJET++ model

Using the HYDJET++ model, we measure the higher-order flow harmonics $v_{n}$(n=2,3,4) of (multi-) strange hadrons in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. We have compared our model results and experimental data at RHIC and LHC energies. The model reproduces the higher flow harmonics of (multi-) strange hadrons as a function of $p_{T}$, centrality, and quark content. We have studied and discussed mass ordering of flows $v_{n}$(n=2,3,4) among $π^{+}+π^{-}$, $K^{-}+K^{+}$, $K_{s}^{0}$, $p+\overline{p}$, $Λ+\overlineΛ$, $Ξ^{-}+\overlineΞ^{+}$, $Ω^{-}+\overlineΩ^{+}$ at low $p_{T}$ and the baryon-meson grouping at intermediate $p_{T}$. NCQ scaling using the HYDJET++ model and its comparison with experimental results at RHIC and LHC energies have also been discussed. Study of flow harmonics behaviour in RHIC and LHC energy regimes will provide an additional insight into the dynamics of anisotropic flow and the effect of radial flow expansion in the system.

hep-ph↗

arXiv2018

Transverse Momentum Distribution and Elliptic Flow of Charged Hadrons in $U$+$U$ collisions at $\sqrt{s_{NN}}=193$ GeV using HYDJET++

Recent experimental observations of the charged hadron properties in $U+U$ collisions at $193$ GeV contradict many of the theoretical models of particle production including two-component Monte Carlo Glauber model. The experimental results show a small correlation between the charged hadron properties and the initial geometrical configurations (e.g. body-body, tip-tip etc.) of $U+U$ collisions. In this article, we have modified the Monte Carlo HYDJET++ model to study the charged hadron production in $U+U$ collisions at $193$ GeV center-of-mass energy in tip-tip and body-body initial configurations. We have modified the hard as well as soft production processes to make this model suitable for $U+U$ collisions. We have calculated the pseudorapidity distribution, transverse momentum distribution and elliptic flow distribution of charged hadrons with different control parameters in various geometrical configurations possible for $U+U$ collision. We find that HYDJET++ model supports a small correlation between the various properties of charged hadrons and the initial geometrical configurations of $U+U$ collision. Further, the results obtained in modified HYDJET++ model regarding $dn_{ch}/dη$ and elliptic flow ($v_{2}$) suitably matches with the experimental data of $U+U$ collisions in minimum bias configuration.

nucl-th↗

arXiv2018

Correlations and Event-by-Event Fluctuations in High Multiplicity Events Produced in $^{208}$Pb-$^{208}$Pb Collisions

Analysis of high multiplicity events produced in 158A GeV/c $^{208}$Pb-$^{208}$Pb collisions is carried out to study the event-by-event fluctuations. The findings reveal that the method of scaled factorial moments can be used to identify the events having densely populated narrow phase space bins. A few events sorted out adopting this approach are individually analyzed. It is observed that these events do exhibit large fluctuations in their pseudorapidity, $η$ and azimuthal angle, $ϕ$ distributions arising out due to some dynamical reasons. Two particle $Δη$-$Δϕ$ correlation study applied to these events too indicates that some complex two-dimensional structure of significantly high magnitude are present in these events which might have some dynamical origin. The findings reveal that the method of scaled factorial moments may be used as an effective triggering for events with large dynamical fluctuations.

hep-ex↗

arXiv2018

The Rapidly Changing Landscape of Conversational Agents

Conversational agents have become ubiquitous, ranging from goal-oriented systems for helping with reservations to chit-chat models found in modern virtual assistants. In this survey paper, we explore this fascinating field. We look at some of the pioneering work that defined the field and gradually move to the current state-of-the-art models. We look at statistical, neural, generative adversarial network based and reinforcement learning based approaches and how they evolved. Along the way we discuss various challenges that the field faces, lack of context in utterances, not having a good quantitative metric to compare models, lack of trust in agents because they do not have a consistent persona etc. We structure this paper in a way that answers these pertinent questions and discusses competing approaches to solve them.

cs.AI↗

arXiv2018

Universal Freezeout Condition for Charged Hadrons in a Hybrid Approach

Hadronic freezeout during the evolution of the medium created in heavy-ion collisions is an important phenomena. It is quite useful to find a universal freezeout condition for each and every nuclear collisions. In this article, we have constructed a hybrid model to calculate the ratio of transverse energy to total mean multiplicity $E_{T} /N_{ch}$, since this ratio can possibly act as a freezeout condition in heavy-ion collision experiments. Present hybrid model blends two approaches : Tsallis statistics and wounded quark approach. Recently, Tsallis statistics has been reliably used to obtain the transverse momentum distribution of charged hadrons produced in relativistic ion collisions. On the other side it has been shown that the pseudorapidity distribution of charged hadrons can be calculated satisfactorily using the wounded quark model (WQM). We have used this hybrid model to calculate the transverse energy density distributions, $dE_{T}/dη$ at midrapidity using charged particle pseudorapidity distributions, $dN_{ch}/dη$ and mean transverse momentum $\langle p_{T} \rangle$ in various type of nuclear collisions. We found that present hybrid model satisfactorily explains the experimental data whether other models fail to reproduce the data at central and at peripheral collisions simultaneously. Finally, ratio of transverse energy to total mean multiplicity, $E_{T} /N_{ch}$ has been computed within hybrid model and compared with the available experimental data at RHIC and LHC energies. We observed no explicit dependence of $E_{T} /N_{ch}$ on energy as well as centrality and thus it can definitely act as a freezeout criteria.

hep-ph↗