Intermediate Silicon Tracker in sPHENIX at RHIC

TL;DR

The paper describes the development and performance of the Intermediate Silicon Tracker (INTT) in the sPHENIX experiment at RHIC, highlighting its role in enhancing tracking precision and timing resolution for heavy-ion collision studies.

Contribution

It introduces the INTT system in sPHENIX, detailing its design, capabilities, and initial performance results in heavy-ion and proton collisions.

Findings

INTT improves tracking accuracy in sPHENIX.

INTT provides precise timing to distinguish pile-up events.

Initial data shows successful integration and operation of INTT.

Abstract

The sPHENIX collaboration has been taking data since 2023 at the Relativistic Heavy Ion Collider in BNL to study the Quark-Gluon Plasma and cold Quantum Chromodynamics (QCD). The tracking system of sPHENIX consists of a time projection chamber, a MAPS-based vertex detector, and an intermediate silicon tracker (INTT). Together with the sPHENIX full barrel calorimeter system, the measurement of the heavy-flavor jets and the upsilon-state identification are enabled. INTT, surrounding the collision point azimuthally at approximately 10 cm away with two layers of silicon strip sensors, detects hit points in the intermediate area of the tracking system to enhance tracking precision. Thanks to the good timing resolution of INTT, it also provides timing information to corresponding hits of other tracking detectors. This capability eliminates pile-up events due to misidentifying bunch crossings. This proceeding discusses the achievements of INTT using Au+Au collision data taken in 2023, and the status of INTT commissioning with proton+proton collisions in 2024.