Speaker
Description
One of the first proposed signatures of quark-gluon plasma (QGP) formation in heavy ion collisions was strangeness enhancement [1]. Due to its strange quark content, the $K^*$ meson is a good probe for the study of the QGP formed in heavy-ion collisions. $K^*$-meson production was previously measured by PHENIX [2] in symmetric Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV [3]. To continue the study of the QGP properties, we have performed analyses of $K^*$-meson production in asymmetric Cu+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV as well as collisions of highly deformed uranium nuclei at $\sqrt{s_{NN}}$ = 192 GeV. In this talk, we present invariant transverse momentum spectra and nuclear modification factors of $K^*$-mesons measured in Cu+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and U+U collisions at $\sqrt{s_{NN}}$ = 192 GeV. In central Cu+Au and U+U collisions in the intermediate transverse momentum range, $K^*$-meson yields are less suppressed than the yields of non-strange mesons such as $\pi^0$, $\eta$, and $\omega$, which might indicate that additional particle production mechanisms are involved in $K^*$-meson production. Production of $K^*$-mesons in Cu+Cu, Cu+Au, and U+U collisions scales with number of participants and seems to depend on nuclear overlap size, but not on its geometry [4]. Implications for hadronization and strangeness production will be discussed.
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- A. Adare et al, Measurement of $K_S^0$ and $K^{*0}$ in p+p, d+Au, and Cu + Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV, Phys. Rev. C 90, 054905 (2014)
- I. Mitrankov, Scaling properties of high-pT light hadrons from small to large systems by PHENIX. Proceedings of Science, 2018, Volume 345
