Topological reconstruction of open charm mesons using electron tagging

TL;DR

This paper reports the first successful topological reconstruction of open charm mesons in proton-proton collisions at 200 GeV using electron tagging, revealing a clear D0 signal and indications of prompt charm pair production.

Contribution

It introduces a novel electron tagging technique for reconstructing open charm mesons and demonstrates its effectiveness in p+p collisions at RHIC energies.

Findings

Clear D0 signal with S/B ratio of 1/7

Observation of a two-peak azimuthal correlation structure

First indications of prompt charm meson pair production

Abstract

We present first results on the topological reconstruction of open charm mesons in p+p collisions at $\snn$ = 200 GeV using electron tagging. The analysis makes use of the full acceptance of the STAR electromagnetic calorimeter during Run VI data taking. A clear D$^0$ signal is obtained with a remarkable signal-to-background ratio of about 1/7 and a signal significance of about 4. The azimuthal correlation distribution of the subleading electrons associated with open charm mesons exhibits a two-peak structure. We found first indications for prompt charm meson pair production. This correlation technique allows detailed energy loss measurements of open charm mesons in heavy-ion collisions.