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We attempt to deal with the direct photon production phenomena in p+p, d+Au and Au+Au collisions at RHIC energy, √sNN = 200 GeV and in Pb+Pb-collisions at LHC energy, √sNN = 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. [ABSTRACT FROM AUTHOR]

We look at some crucial aspects of J/&PSgr;-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 are also enunciated in some detail. The results are in fairly in good agreement with both measured data and the results obtained on the basis of other models of the standard variety. The impact and implications of this comparative study are also discussed. [ABSTRACT FROM AUTHOR]

The transverse momentum spectra of secondary η particles produced in P+P, D + Au and Au + Au interactions at $\sqrt{s_{NN}} = 200~{\rm GeV}$ at different centralities have been studied in the light of a nonextensive thermodynamical approach. The results and the possible thermodynamical insights, thus obtained, about the hadronizing process have also been discussed in detail. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In continuation of our previous works, we attempt here to understand the nature of data on direct photon and neutral pion production in the latest RHIC experiments at $\sqrt{s_{NN}}=200~{\rm GeV}$ for all the different interactions studied therein from the viewpoint of a nonstandard outlook and approach as described in Refs. 4 and 5 here. It is found that the proposed model could account for the data-sets with a fair degree of success. [ABSTRACT FROM AUTHOR]

Experimental studies on gold–gold collisions at RHIC at $\sqrt{s_{NN}} = 200~{\rm GeV}$ have produced a vast amount of data and results to be analyzed in the light of various competing models in the domain of multiparticle production scenario. We have chosen to analyze here the measured data on the pT-spectra of various light and nonstrange secondaries and some of their very important ratio-behaviors at the various centralities of the collision in the light of a version of the sequential chain model. The agreements between measured data and theoretical plots are found to be modestly satisfactory. [ABSTRACT FROM AUTHOR]

In the present study on proton–Beryllium collisions at two distinctly different energies obtained by one FERMILAB Collaboration, we attempt to focus on the unsettled controversy between the exponential models versus power law models, both of which are found to be in wide applications. The study concludes that none of them could be abandoned finally. And the resolution of the debate, the authors argue, might rest, not on the acceptance of just any one of them, but on a suitable combination of both of them, acting in the different domains of the transverse momentum values. [ABSTRACT FROM AUTHOR]

The oncoming recent data on production of J/Ψ mesons in some high energy particle and nuclear collisions are of special importance in view of the controversies centering around the so-called suppression or enhancement mechanisms for this particle-species. We will try to explain here the features of some of the basic observables on J/Ψ production with the help of an approach which has no direct links with quark–gluon plasma (QGP) considerations, but can interpret a large amount of data related to the proposed physical signatures of QGP. The final outcome, based on the present study, amounts to stating the fact that the J/Ψ production is neither suppressed nor enhanced; rather it exhibits both in our theoretical approach and also in the experimental measurements a behavior which is just as normal as many other secondaries, with only specificities of its own intrinsic quantum numbers and the very massive nature. [ABSTRACT FROM AUTHOR]

This work is in response to the stimulus received from our fairly successful attempt at understanding in the recent past the problem of direct photon production only in gold–gold and lead–lead collisions from the viewpoint of a non-standard approach. The same nonconventional formalism would, once again, be applied to analyze the vast array of measurements on the inclusive cross sections of direct photons produced in several purely nuclear or hadronuclear collisions at very high energies. Besides, some of the cross section ratios would also be calculated and be compared with data on them. All this reveals and indicates a modest agreement between the model-based calculations and the actual measurements. The authors would also endeavor here to adduce the reasons for the discrepancies, if any. [ABSTRACT FROM AUTHOR]

The study presented here pertains to the model-based analyses for production of some important charged secondaries in lead-lead and gold-gold collisions at AGS, SPS and RHIC energies. We examine the role of a particular version of the Sequential Chain Model (SCM) in interpreting the data on the production of only the secondary mesons of the most abundant variety in relativistic nucleus-nucleus collisions. The initial results derived for basic pp collisions have been transformed into the corresponding cases for nucleus-nucleus collisions through the appropriate physical-mathematical formalisms. The agreement between the model of choice and the measured data for the most important varieties of mesons in the two above-stated nuclear collisions could so far be rated to be barely modest. This is presumably due to our neglect of the effects of rescattering and cascading, while we choose to obtain only the first-order results in the initial attempt. [ABSTRACT FROM AUTHOR]

The RHIC measurements on the transverse momentum spectra of the main category of secondary particles produced in the Au + Au collisions were reported in the recent past. The combination of the phenomenological approaches we adopted provide a satisfactory, alternative framework for understanding and explaining the latest data-spurts on charged pions, kaons and the protons--antiprotons. The comparison of the performances by the contesting models on a select kind of secondary (π[SUP+]) which belongs to the most abundant variety has also been made. The impact and implications of all these have also been spelt out in the end. [ABSTRACT FROM AUTHOR]

In the recent past the NA44 Collaboration reported measurements on production of deuteron spectra in SS , SPb and PbPb collisions at the CERN-SPS. This has opened up an avenue, within the confines of the coalescence model, for calculating the source radii of protons, antiprotons and the average phase space densities (APSD) which are being projected, of late, as a reliable observable for studying the freeze-out behaviour of high-energy nuclear collisions. Instead of the thermal or thermodynamical model, we have applied in the present work a set of two models with a new parametrisation which yielded in the past a fair description of some observations on the APSD nature for pion production in nuclear collision. The combination provides here a satisfactory analysis of the pT spectra for both proton and deuteron production and allows us to obtain the values of the hypothesized radii of the assumed spheres of the expansion dynamics and also of the average phase space densities for protons. The values thus arrived at are also quite consistent with the RQMD predictions in the standard literature. [ABSTRACT FROM AUTHOR]

We attempt in this paper to deal with some aspects of the direct photon production phenomenon mainly in the Pb+Pb and Au+Au collisions on the basis of a model for production of the same particle species in PP collisions. The results have, thereafter, been converted to those for a few AB/AA interactions through an appropriate mechanism. Comparison of the theoretical results obtained on the basis of model-based calculations with measured data on the relevant observables leads to a fair agreement between them. This reflects modestly the fair achievements attained by the models that are made use of in the present work. [ABSTRACT FROM AUTHOR]

The present paper aims at testing a very simple approach to interpret the characteristics of inclusive production of pions in high energy NA and AA collisions by a somewhat in-depth analysis of the same for NN interactions; and also at reporting here thus some interesting observations made on the nature of rapidity and transverse momentum spectra of the produced pions. And this approach is built upon a newly offered master formula holding the key for converting the results of high energy nucleon-nucleon (NN) collision to the corresponding observables on differential and inclusive cross-sections for both nucleon-nucleus and nucleus-nucleus (heavy ion) collisions in a generalized form. The proposed formulae, used in a somewhat phenomenological way, can provide modestly reliable parametrization of data in the broad range of collision energy and the varied range of projectile-target combinations. This opens up the possibility of understanding in a quite unified manner the large amount of data on the rapidity and transverse momentum spectra in a wide range of interactions and energies starting right from ISR, rather Bevelac, to the relativistic heavy ion collisions (RHIC) via the various collider scales of energy. The agreements between the data and calculations, in most cases, are quite satisfactory both qualitatively and quantitatively. While highlighting this success, the limitation of the approach has also been pointed out in the end as clearly and categorically as possible. [ABSTRACT FROM AUTHOR]

Within the framework of coalescence model, the problem of antideuteron (&Dmacr;) production in some high energy nuclear collisions has here been studied with the help of a new combination of models (NCM) outlined in some detail in the text. The totality of the approach, including one useful parametrization, adopted here leads us to obtain finally some theoretical results which are modestly in agreement with the measured data on various aspects of antideuteron production in both Pb + Pb and Au + Au collisions at moderately high energies. The implications of all this are discussed at the end of the paper. [ABSTRACT FROM AUTHOR]

We deal with some of the main characteristics of proton and deuteron production in Au + Au reactions at 11.6A GeV/c with the help of a new approach. From the viewpoint of the combination of two models and an important phenomenological parametrization, we analyze both laboratory data and the model-constructs from which we finally summarize two crucial features: (i) nucleon-nucleon and nucleus-nucleus collisions could be treated on a unified footing; (ii) production of hadrons like pions, protons etc. and deuterons as well, could be studied in a somewhat similar way. Besides, it is also shown that the totality of the approach outlined and utilized here is quite capable of obtaining the physical projections based on the popular relativistic quantum molecular dynamic (RQMD) model, and can also accommodate some actual measurements already made in the past. [ABSTRACT FROM AUTHOR]

We attempt here to deal with some of the important characteristics of secondary antiproton production in various high energy nuclear interactions on the basis of a model for production of particles in PP collisions. The results have, thereafter, been converted to those for AA collisions through an appropriate mechanism. The effect of rescattering and cascading in the production processes and on the chosen models has also been incorporated in a phenomenological manner. Comparison of the calculated results with data on the relevant observables leads to a striking agreement and this fair success is claimed here to obviously signal the strength of the basic models that are applied in the present work. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to focus on the possible effective role of two relatively less-known models in analyzing comprehensively the very up-to-date data on protonair inelastic cross-sections at high and ultra high energies. The standard versions of all the familiar simulation-based multiparticle production models, which nowadays normally claim front-ranking positions, address on the contrary, only a small part of the cross-section data for a very limited or sectional range of energy values. Against this background, the relevance and impact of the present study have finally been highlighted. [ABSTRACT FROM AUTHOR]

Experiments involving proton—proton collisions at energies √sNN = 0.9, 2.76 and 7 TeV in the large hadron collider produce a vast amount of high-precision data. In this work, we analyze two aspects of the measured data, viz., (i) the pT-spectra of pions, kaons, proton-antiproton at the above-mentioned energies, and (ii) some of their very important ratio behaviors, in the light of a version of the sequential chain model. The agreements between the measured data and the model-based results are generally found to be modestly satisfactory. [ABSTRACT FROM AUTHOR]