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Large Hadron Collider (LHC) had produced a vast amount of high precision data for high energy heavy ion collision. We attempt here to study (i) transverse momenta spectra, (ii) $K/\pi$, $p/\pi$ ratio behaviours, (iii)rapidity distribution, and (iv) the nuclear modification factors of the pion, kaon and antiproton produced in $p+p$ and $Pb+Pb$ collisions at energy $\sqrt{s_{NN}}$ = 2.76 TeV, on the basis of Sequential Chain Model (SCM). Comparisons of the model-based results with the measured data on these observables are generally found to be modestly satisfactory., Comment: 11 pages, 2 tables, 5 figures

Experiments involving proton-proton collisions at energies $\sqrt{s_{NN}}$ = 0.9, 2.76 and 7 TeV in Large Hadron Collider (LHC) have produced a vast amount of high-precision data. Here, in this work, we have chosen to analyse the two aspects of the measured data, viz., (i) the $p_T$ -spectra of pions, kaons, proton-antiproton at above-mentioned energies, and (ii) some of their very important ratio-behaviours, in the light of a version of the Sequential Chain Model (SCM). The agreements between the measured data and model-based results are generally found to be modestly satisfactory., Comment: 10 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:0907.2008

We attempt, in this paper, to deal with the direct photon production phenomena in $p+p$, $d+Au$ and $Au+Au$ collisions at RHIC energy, $\sqrt{s_{NN}}$ = 200 GeV and in $Pb+Pb$-collisions at LHC energy, $\sqrt{s_{NN}}$ = 2.76 TeV on the basis of a non-standard framework outlined in the text. Comparisons of the model-based results with the measured data on some observables reveal fair agreement; and they are modestly consistent with the results obtained by some other models of `Standard' framework., Comment: 10 pages, 5 figures;To appear in CHIN. PHYS. LETT. Vol. 30, No. 6 (2013) 062502

We attempt here to understand successfully some crucial aspects of $J/\Psi$-production in some high energy nuclear collisions in the light of a non-standard framework outlined in the text. It is found that the results arrived at with this main working approach here is fairly in good agreement with both the measured data and the results obtained on the basis of some other models of the `standard' variety. Impact and implications of this comparative study have also been precisely highlighted in the end., Comment: 14 pages, 7 figures, to appear in Open Journal of Microphysics. arXiv admin note: substantial text overlap with arXiv:0906.2612, arXiv:1110.5582, and overlap with arXiv:1103.6269, arXiv:1007.4513

From the very early days of Particle Physics, both experimental and theoretical studies on proton-proton collisions had occupied the center-stage of attention for very simple and obvious reasons. And this intense interest seems now to be at peak value with the onset of the Large Hadron Collider (LHC)-studies at TeV ranges of energies. In this work, we have chosen to analyse the inclusive cross-sections, the rapidity density, the $K/\pi$ and $p/\pi$-ratio behaviours and the $$-values, in the light of the Sequential Chain Model (SCM). And the limited successes of the model encourage us to take up further studies on several other aspects of topmost importance in particle physics with the same approach., Comment: 14 pages, 3 tables, 7 figures; to appear in Journal of Modern Physics

We would attempt, in this work, at dwelling upon some crucial aspects of $J/\Psi$-production in a few high energy nuclear collisions in the light of a non-standard model which is outlined in the text. The underlying physical ideas, assumptions and ansatzs have also been enunciated in some detail. It is found that the results arrived at with this main working approach here are fairly in good agreement with both the measured data and the results obtained on the basis of some other models of the `standard' variety. Impact and implications of this comparative study have also been precisely highlighted in the end., Comment: 8 pages, 7 figures

This study aims at understanding the nature of measured data on the rapidity spectra of some heavy baryons [$\Lambda$, $\Lambda$bar, $\Xi^-$ & $\Xi$bar$^+$] produced in the nuclear collisions at some modestly high energies. Furthermore, our objective is also to build up a comprehensive and consistent methodology to analyze the data on this specific observable which has a very important place in the domain of High Energy Physics (HEP). On an overall basis, our target here attains a moderate degree of success even for production of such rare secondaries. In addition to this, the limitations of such an approach have also been pointed out., Comment: 19 pages, 14 figures, Accepted for publication in IL Nuovo Cimento B

The transverse momentum spectra of secondary $\eta$ particles produced in $P+P$, $D+Au$ and $Au+Au$ interactions at $\sqrt{s_{NN}}=200$ GeV at different centralities have been studied in the light of a non-extensive thermodynamical approach. The results and the possible thermodynamical insights, thus obtained, about the hadronizing process have also been discussed in detail., Comment: 16 pages, 7 figures; Accepted for publication in IJMPA

Experiments involving copper-copper collisions at the RHIC-BNL (USA) at energies $\sqrt{s_{NN}}$ = 22.5, 62 and 200 GeV have produced a vast amount of high-precision data which are to be analysed in the light of various competing models in the domain of multiparicle production scenario. We have chosen to analyse here the measured data on the $p_T$ -spectra of various light and non-strange secondaries at various energies mentioned above, some of their very important ratio-behaviours at the various centralities of the collisions and the nuclear modification factors $R_{AA}$ and $R_{CP}$ in the light of a version of the Sequential Chain Model (SCM). The agreements between the measured data and model-based results are generally found to be modestly satisfactory. Besides, our obtained results have also been compared with results based upon two approaches with strong standard model flavour, of which one is purely pQCD-oriented and is forwarded by Vitev., Comment: 35 pages, 14 Figures, 4 Tables; Title, Abstract and the text changed; To appear in Il Nuovo Cimento B

Reliable data from the very recent high-precision measurements on the antiproton fluxes and the antiproton-to-proton ratios by the PAMELA Collaboration at relatively much higher energies are now available. The results with regard to antiproton production phenomena spring no special surprises; rather they are sharply in contrast with and contradiction to the case of positron production at the same energy-range. However, the totality of data on antiproton production from the past experiments to the very recent PAMELA outburst seem to be a very challenging exercise for interpretation in terms of the secondary production mechanisms alone, the galactic propagation model etc against the background of the `dark-matter'-related controversy. In the present work we assume the validity of the simple leaky box model, choose a simple particle production model and attempt at providing a comprehensive interpretation of the totality of data on both antiproton flux measurements and the $\overline{P}/P$ ratio-values for the various experiments ranging from BESS, CAPRICE to the latest PAMELA experiment. With the assumption of no contribution from the exotic sources to the antiproton production process, our model and the method describe the totality of the measured data with a fair degree of success., Comment: 16 Pages, 5 Figures. Title changed, Abstract changed, some minor changes in references, typos

We have attempted to develop here tentatively a model for $J/\Psi$ production in p+p, d+Au, Cu + Cu and Au + Au collisions at RHIC energies on the basic ansatz that the results of nucleus-nucleus collisions could be arrived at from the nucleon-nucleon (p + p)-interactions with induction of some additional specific features of high energy nuclear collisions. Based on the proposed new and somewhat unfamiliar model, we have tried (i) to capture the properties of invariant $p_T$ -spectra for $J/\Psi$ meson production; (ii) to study the nature of centrality dependence of the $p_T$ -spectra; (iii) to understand the rapidity distributions; (iv) to obtain the characteristics of the average transverse momentum $< p_T >$ and the values of $< p_T^2 >$ as well and (v) to trace the nature of nuclear modification factor. The alternative approach adopted here describes the data-sets on the above-mentioned various observables in a fairly satisfactory manner. And, finally, the nature of $J/\Psi$-production at Large Hadron Collider(LHC)-energies deduced on the basis of our chosen model has been presented in a predictive way against the RHIC-yields, both calculated for the most central collisions and on the same model., Comment: 24 Pages, 14 Figures

The nature of transverse momentum dependence of the inclusive cross-sections for secondary pions produced in high energy hadronic($PP$), hadronuclear($PA$) and nuclear($AA$) collisions has here been exhaustively investigated for a varied range of interactions in a unified way with the help of a master formula. This formula evolved from a new combination of the basic Hagedorn's model for particle(pion) production in PP scattering at ISR range of energies, a phenomenological approach proposed by Peitzmann for converting the results of $NN(PP)$ reactions to those for either $PA$ or $AA$ collisions, and a specific form of parametrization for mass number-dependence of the nuclear cross sections. This grand combination of models(GCM) is then applied to analyse the assorted extensive data on various high energy collisions. The nature of qualitative agreement between measurements and calculations on both the inclusive cross-sections for production of pions, and some ratios of them as well, is quite satisfactory. The modest successes that we achieve here in dealing with the massive data-sets are somewhat encouraging in view of the diversity of the reactions and the very wide range of interaction energies., Comment: 19 pages, 19 figures