The effect of atom losses on the distribution of rapidities in the one-dimensional Bose gas

We theoretically investigate the effect of atom losses in the one-dimensional (1D) Bose gas with repulsive contact interactions, a famous quantum integrable system also known as the Lieb-Liniger gas. The generic case of KK-body losses (K=1,2,3,\dotsK=1,2,3,…) is considered. We assume that the loss rate is much smaller than the rate of intrinsic relaxation of the system, so that at any time the state of the system is captured by its rapidity distribution (or, equivalently, by a Generalized Gibbs Ensemble). We give the equation governing the time evolution of the rapidity distribution and we propose a general numerical procedure to solve it. In the asymptotic regimes of vanishing repulsion – where the gas behaves like an ideal Bose gas – and hard-core repulsion – where the gas is mapped to a non-interacting Fermi gas –, we derive analytic formulas. In the latter case, our analytic result shows that losses affect the rapidity distribution in a non-trivial way, the time derivative of the rapidity distribution being both non-linear and non-local in rapidity space.

Centrality dependence of pseudo-rapidity distribution in nucleus–nucleus collisions at (4.1–4.5) AGeV/c

A detailed study of the centrality dependence of pseudo-rapidity distribution has been carried out for [Formula: see text]O-emulsion interactions at 4.5[Formula: see text]AGeV/c and [Formula: see text]Ne-emulsion interactions at 4.1[Formula: see text]AGeV/c using nuclear emulsion track detector. Depending on the values of the total charges or sum of the charges of noninteracting projectile fragments, event samples were classified into four centrality classes. Maximum pseudo-rapidity density, average pseudo-rapidity values, moments of pseudo-rapidity distribution along with skewness and kurtosis of the distributions have been investigated for different centrality classes.

Distribution of strange particles transverse momentum and rapidity in high energy proton–proton collisions at s = 0.9 TeV at LHC

In this paper, we have studied the spectra of strange particles in pp collision at [Formula: see text] = 0.9 TeV by using different simulation models, EPOS-1.99, SIBYLL-2.3c, QGSJETII-04 and EPOS-LHC. The transverse momentum and rapidity distribution in the [Formula: see text] range of [Formula: see text] GeV/c and [Formula: see text] GeV/c, respectively, are investigated for the strange particles, [Formula: see text], [Formula: see text], [Formula: see text]. Similarly, a comparative study is done for the ratio of [Formula: see text] and [Formula: see text] as a function of transverse momentum and rapidity. The validity of simulation models is tested by comparing simulation results to the CMS experimental data at [Formula: see text] = 0.9 TeV. For [Formula: see text] distributions, the EPOS-LHC model in the [Formula: see text] range [Formula: see text] GeV/c, [Formula: see text] GeV/c and in [Formula: see text] GeV/c while EPOS-1.99 model in the [Formula: see text] range [Formula: see text] GeV/c and QGSJETII-04 model in the [Formula: see text] range [Formula: see text] GeV/c as well as, [Formula: see text] GeV/c explain the experimental data well. For the, [Formula: see text] and [Formula: see text] versus transverse momentum distributions, EPOS-LHC model in the [Formula: see text] range of, [Formula: see text] GeV/c and [Formula: see text] GeV/c, EPOS-1.99 model in the [Formula: see text] range, [Formula: see text] GeV/c, SIBYLL-2.3c model in the [Formula: see text] range, [Formula: see text] GeV/c and QGSJETII-04 model in the [Formula: see text] range [Formula: see text] GeV/c explain the experimental data very well. Similarly, for [Formula: see text] and [Formula: see text] versus rapidity distribution QGSJETII-04 predictions in the rapidity region, [Formula: see text], [Formula: see text], and [Formula: see text], while EPOS-LHC model in the region, [Formula: see text], very well explained the experimental data. Although good comparison of the models predictions with the experimental data is observed, none of them completely describe the experimental data the spectra of strange particles over the entire [Formula: see text] and [Formula: see text] range.

A continuous wavelet transform analysis of multiparticle emission data at SPS energies

Continuous wavelet transform approach has been applied to the pseudo-rapidity distribution of shower tracks produced in [Formula: see text]O–AgBr interactions at 60[Formula: see text]AGeV and [Formula: see text]S–AgBr interactions at 200[Formula: see text]AGeV. Multiscale analysis of wavelet pseudo-rapidity spectra has been performed in order to find out the overabundance of produced tracks at some preferred pseudo-rapidity values, i.e., production of particle clusters. Presence of ring-like correlation is not confirmed from the analysis in pseudo-rapidity space only. The clusterization effect may be attributed to the presence of Bose–Einstein correlation among the produced tracks. Comparison of experimental results with that obtained from analyzing events generated by FRITIOF and UrQMD codes is not reproduced.