Intercepts of the momentum correlation functions in μ-Bose gas model and their asymptotics
A. M. Gavrilik, A. P. Rebesh
备注：
9 pages (two column), 3 figures; v.3: abstract, introduction rewritten, the paper rewritten and shortened (one subsection, appendix and table omitted), two references added; v.4: three new formulas (27),(29),(32) with exact results are added, figures redone into two 2-panel ones
The so-called μ-deformed oscillator (or μ-oscillator) introduced by A.Jannussis, though possesses rather exotic properties with respect to other better known deformed oscillator models, also has good potential for diverse physical applications. In this paper, the corresponding μ-Bose gas model based on μ-oscillators is explored. Within this model, the intercepts λ^(2)(K) and λ^(3)(K) of two- and three-particle momentum correlation functions are calculated with the goal of possible application for modeling the non-Bose type behavior of the intercepts of two- and three-pion correlations, observed in the experiments on relativistic heavy ion collisions. In derivation of intercepts, different orders of approximation in the deformation parameter μare considered. Our analysis also yields asymptotical behavior of the intercepts λ^(2)(K) and λ^(3)(K). The results for λ^(2)(K) are compared with experimental data, and with earlier known results drawn using other deformed Bose gas models.
Recently, the deformed μ-Bose gas model based on so called μ-deformed oscillators was proposed. For that model, the intercepts of r-particle momentum correlation functions (correlation functions at coinciding momenta of particles) were treated for r=2,3, within certain order of approximation in μ. In this work, we derive for μ-Bose gas model the {\it exact} expressions for r-particle correlation function intercepts, for all r, through Lerch transcendent and find their asymptotics (as functions of μ). For 2-, 3-particle intercepts and deformed distribution function <a^†_k a_k> the dependence on…
Symmetric Tamm-Dancoff (STD) type $q$-deformed quantum oscillators are used as the base for constructing the respective STD type $q$-Bose gas model. In this letter, within the STD $q$-deformed Bose gas model we derive explicit analytic expressions for the $r$-particle momentum distribution functions, and for the (momentum) correlation function intercepts of 2nd, 3rd, and any $r$th order. Besides, we obtain large-momentum asymptotic formulas for the $r$th order intercepts which show dependence on the $q$-parameter only. The obtained formulas provide new example, in addition to already known two…
In the recently proposed two-parameter $\tildeμ,q$-deformed Bose gas model [Ukr. J. Phys. {\bf 58}, 1171 (2013), arXiv:1312.1573] aimed to take effectively into account both compositeness of particles and their interaction, the $\tildeμ,q$-deformed virial expansion of the equation of state (EOS) was obtained. In this paper we further explore the $\tildeμ,q$-deformation, namely the version of $\tildeμ,q$-Bose gas model involving deformed distributions and correlation functions. In the model, we explicitly derive the one- and two-particle deformed distribution functions and the intercept of two-…
The approach based on multimode system of q-deformed oscillators and the related picture of ideal gas of q-bosons enables to effectively describe the observed non-Bose type behaviour, in experiments on heavy-ion collisions, of the intercept (or the "strength") $λ$ of the two-particle correlation function of identical pions or kaons. In this paper we extend main results of that approach in the two aspects: first, we derive in explicit form the intercepts of n-particle correlation functions in the case of q-Bose gas model and, second, provide their explicit two-parameter (or qp-) generalization.
We propose and develop to some extent a novel approach, which allows us to effectively describe, for relativistic heavy-ion collisions, the empirically observed deviation from unity of the intercept λ(i.e. the measured value corresponding to zero relative momentum {\bf p} of two registered identical pions or kaons) of the two-particle correlation function C(p,K). The approach is based on the use of two versions of the so-called q-deformed oscillators and the corresponding picture of ideal gases of q-bosons. By these techniques the intercept λis put into direct correspondence with the deformati…
An approach is proposed enabling to effectively describe, for relativistic heavy-ion collisions, the observed deviation from unity of the intercept λ(measured value corresponding to zero relative momentum {\bf p} of two registered identical pions or kaons) of the two-particle correlation function C(p,K). The approach uses q-deformed oscillators and the related picture of ideal gas of q-bosons. In effect, the intercept λis connected with deformation parameter q. For a fixed value of q, the model predicts specific dependence of λon pair mean momentum {\bf K} so that, when |{\bf K}|\gsim 500 - 60…
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