Lévy-stable two-pion Bose-Einstein correlations in √{sNN}=200 GeV Au +Au collisions
Abstract
We present a detailed measurement of charged two-pion correlation functions in 0-30% centrality √{s NN}=200 GeV Au +Au collisions by the PHENIX experiment at the Relativistic Heavy Ion Collider. The data are well described by Bose-Einstein correlation functions stemming from Lévy-stable source distributions. Using a fine transverse momentum binning, we extract the correlation strength parameter λ , the Lévy index of stability α , and the Lévy length scale parameter R as a function of average transverse mass of the pair mT. We find that the positively and the negatively charged pion pairs yield consistent results, and their correlation functions are represented, within uncertainties, by the same Lévy-stable source functions. The λ (mT) measurements indicate a decrease of the strength of the correlations at low mT. The Lévy length scale parameter R (mT) decreases with increasing mT, following a hydrodynamically predicted type of scaling behavior. The values of the Lévy index of stability α are found to be significantly lower than the Gaussian case of α =2 , but also significantly larger than the conjectured value that may characterize the critical point of a second-order quark-hadron phase transition.
- Publication:
-
Physical Review C
- Pub Date:
- June 2018
- DOI:
- 10.1103/PhysRevC.97.064911
- arXiv:
- arXiv:1709.05649
- Bibcode:
- 2018PhRvC..97f4911A
- Keywords:
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- Nuclear Experiment
- E-Print:
- 448 authors, 25 pages, 11 figures, 4 tables, 2010 data. v3 is version accepted for publication in Phys. Rev. C with some Table II numbers and Fig. 5 updated to match publication. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.html