SearcharxivSearch

arXiv subjects

D. Kincses

Publications and source records attributed to D. Kincses.

3 recordsLinked to original sources

Event-by-event investigation of the kaon pair-source function with EPOS

In high-energy collisions, we can obtain information about the source function by measuring the two-particle Bose-Einstein correlation function and considering its relationship with the phase-space density of the particle-emitting source. While a Gaussian shape is commonly assumed, measurements and anomalous diffusion suggest L\'evy-stable distributions, as observed in the PHENIX experiment for kaon-kaon pair-source functions. Event generators like EPOS allow direct investigation of freeze-out coordinates, facilitating the analysis of the source function. EPOS, a Monte Carlo-based model, simulates high-energy nuclear and particle collisions, integrating Parton-Based Gribov-Regge theory for initial evolution, subsequent hydrodynamic evolution, and hadronization. In this paper, we present an event-by-event analysis of the kaon source function in $\sqrt{s_\text{NN}}$ = 200 GeV Au+Au collisions using the EPOS model.

hep-ph

Coulomb and strong interactions in the final state of HBT correlations for Lévy type source functions

We present detailed calculations about the expected shape of two-pion Bose-Einstein (or HBT) correlations in high energy heavy ion collisions that include a realistic treatment of final state Coulomb interaction as well as strong interactions (dominated by s-wave scattering). We assume Lévy type source functions, a generalization that goes beyond the Gaussian approximation. Various recent experimental results found the use of such source types necessary to properly describe the shape of the measured correlation functions. We find that strong final state interactions may play an important role in the shape of the two-pion correlation functions, especially if one considers source parameters beyond the Gaussian HBT radii. Precise experimental determination of these source parameters (such as Lévy stability exponent, correlation strength, etc.) seems to require the inclusion of the treatment of strong interaction not just for heavier particles (e.g. protons, lambdas) but also in case of two-pion measurements.

hep-ph

Measurements of azimuthal anisotropy and charged-particle multiplicity in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=$200, 62.4, 39, and 19.6 GeV

We present measurements of the elliptic flow, $v_2$, as a function of transverse momentum ($p_T$), pseudorapidity ($η$), and centrality in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=$200, 62.4, 39, and 19.6 GeV. The beam-energy scan of $d$$+$Au collisions provides a testing ground for the onset of flow signatures in small collision systems. We measure a nonzero $v_2$ signal at all four collision energies, which, at midrapidity and low $p_T$, is consistent with predictions from viscous hydrodynamic models. Comparisons with calculations from parton transport models (based on the {\sc ampt} Monte Carlo generator) show good agreement with the data at midrapidity to forward ($d$-going) rapidities and low $p_T$. At backward (Au-going) rapidities and $p_T>1.5$ GeV/$c$, the data diverges from {\sc ampt} calculations of $v_2$ relative to the initial geometry, indicating the possible dominance of nongeometry related correlations, referred to as nonflow. We also present measurements of the charged-particle multiplicity ($dN_{\rm ch}/dη$) as a function of $η$ in central $d$$+$Au collisions at the same energies. We find that in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=$200 GeV the $v_2$ scales with $dN_{\rm ch}/dη$ over all $η$ in the PHENIX acceptance. At $\sqrt{s_{_{NN}}}=$62.4, and 39 GeV, $v_2$ scales with $dN_{\rm ch}/dη$ at midrapidity and forward rapidity, but falls off at backward rapidity. This departure from the $dN_{\rm ch}/dη$ scaling may be a further indication of nonflow effects dominating at backward rapidity.

nucl-ex