sPHENIX

sPHENIX Research Project

sPHENIX Proposal: http://inspirehep.net/record/1341090

The sPHENIX experiment is a next-generation, state-of-the-art jet and heavy flavor detector nearing completion at Brookhaven National Laboratory and scheduled to begin data-taking operations in spring of 2023. The physics goal of sPHENIX is to study and precisely quantify properties of the quark-gluon plasma (QGP) created in high energy collisions between large nuclei in the Relativistic Heavy Ion Collider (RHIC).  Our particular focus is studying the phenomenon of jet modification, whereby the shape and momentum of jets measured in heavy ion collisions is modified by interactions within the QGP. Our programs at sPHENIX and ATLAS together will allow us to constrain the temperature dependence of properties of the QGP. While the center of mass energies the LHC is capable of create a hotter QGP on average, the lower temperature achieved at RHIC is closer to the minimum temperature necessary  to create the QGP, making measurements at RHIC potentially more sensitive to why the QGP behaves as it does. For more on QGP studies at RHIC and the LHC, specifically using jet modification as a probe, see this paper co-authored by Prof. Sickles or the recording of this Illinois Saturday Physics for Everyone talk.

In addition to heavy-ion collisions, collisions of proton beams in sPHENIX will provide the normalization to the heavy-ion program and will, due to the transverse polarization of the protons, enable the study of transverse spin asymmetries, which allow important insights into non-perturbative proton structure described by transverse-momentum dependent (TMD) parton distribution functions (PDFs) or multi-parton correlation functions. 

The Illinois group had the leading role in the development and testing of the sPHENIX Electromagnetic Calorimeter over seven years. Prototyping of the EMCal block design began in 2014 and lasted until full production began in 2018 and concluded successfully in 2021. Our group produced over 80% of the calorimeter modules and participated in beam tests of the EMCal that occurred in 2016 and in 2018 and played leading roles in the analysis and paper writing of both publications. We will continue this leadership position during the upcoming commissioning phase of the detector, including the development of the EMCal’s online monitoring framework, initial energy scale calibrations, and first results on neutral meson measurements. 

The sPHENIX data begins in early 2023 and extends over three years.  We are playing a leading role in the overall experiment with Caroline Riedl serving as co-Chair of the Commissioning Task Force and Anne Sickles serving as Chair of the Publication Board.  Postdoc Anthony Hodges is stationed at Brookhaven and other group members will travel to Brookhaven as needed to participate in data-taking or other collaboration activities.  We anticipate playing leading roles in some of the most exciting physics opportunities with sPHENIX.

 For more information about sPHENIX see the following BNL articles:

• sPHENIX Overview
• sPHENIX Assembly (March 2022)
• sPHENIX Magnet (October 2021)
• sPHENIX Assembly (July 2021)
• sPHENIX CD0 (January 2017)
• sPHENIX Calorimeter (June 2016)
• sPHENIX Beam Test (June 2016)