Non-photonic electron-hadron correlations at STAR

TL;DR

This paper reports measurements of electron-hadron correlations in various collision systems at 200 GeV, revealing modifications in heavy-ion collisions indicative of medium effects on B meson decay contributions.

Contribution

First extraction of B meson decay contributions to non-photonic electrons at high transverse momentum in p+p collisions, and observation of medium-induced modifications in heavy-ion collisions.

Findings

B meson decay contributions up to 9 GeV/c electron p_t in p+p collisions.

Modification of away-side e-h correlations in Cu+Cu and Au+Au collisions.

Evidence of medium effects on heavy-flavor decay electrons.

Abstract

We present STAR's measurements of azimuthal correlations between non-photonic electrons and charged hadrons in p+p, Cu+Cu and Au+Au collisions at 200 GeV. In p+p collisions, from the non-photonic e-h correlation we have extracted the relative B meson semi-leptonic decay contributions to non-photonic electrons up to electron $p_t \sim 9$ GeV/$c$. In central Cu+Cu and Au+Au collisions where a dense medium is created, we find that the e-h correlation on the away side of the trigger non-photonic electron has been modified in comparison with the expectation from PYTHIA simulations.