Hadronic Trigger using electromagnetic calorimeter and particle identification at high-pT with STAR Detector

TL;DR

This paper presents a new online trigger method using the electromagnetic calorimeter at STAR to significantly enhance high-pT hadron detection, enabling better study of resonant states and weak decays.

Contribution

A novel trigger technique utilizing the BEMC to improve high-pT particle statistics and reconstruct resonant states in heavy-ion collision experiments.

Findings

High-pT particle statistics increased by about 100 times.

Trigger efficiency reliably determined via simulation and data-driven methods.

Resonant states and weak decays successfully reconstructed using the trigger.

Abstract

We derive a new method to improve the statistics of identified particles at high transverse momentum (\pt) using online-triggered events by the Barrel Electro-Magnetic-Calorimeter (BEMC) detector. The BEMC is used to select hadronic interaction and energy deposit from showers created by charged hadrons ($\pi^{\pm},K^{\pm}$ and $p$($\bar{p}$)) in the BEMC. With this trigger, the statistics of the high \pt particles are significantly enhanced by about a factor of 100 with selection efficiency up to 20%. In addition, resonant states ($\rho^0$, $K^{\star}$) and weak-decay V0 (\Ks and \La(\aLa)) can be constructed by selecting the BEMC-trigger hadron as one of its daughters. We also show that the trigger efficiency can be obtained reliably in simulation and data-driven approaches.