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abstract: 'A plastic scintillator paddle detector with embedded fiber light guides and photomultiplier tube readout, referred to as the Reaction Plane Detector (RXNP), was designed and installed in the PHENIX experiment prior to the 2007 run of the Relativistic Heavy Ion Collider (RHIC). The RXNP’s design is optimized to accurately measure the reaction plane (RP) angle of heavy-ion collisions, where, for mid-central $\sqrt{s_{NN}}$ = 200 GeV Au+Au collisions, it achieved a $2^{nd}$ harmonic RP resolution of $\sim$0.75, which is a factor of $\sim$2 greater than PHENIX’s previous capabilities. This improvement was accomplished by locating the RXNP in the central region of the PHENIX experiment, where, due to its large coverage in pseudorapidity ($1.0<|\eta|<2.8$) and $\phi$ (2$\pi$), it is exposed to the high particle multiplicities needed for an accurate RP measurement. To enhance the observed signal, a 2-cm Pb converter is located between the nominal collision region and the scintillator paddles, allowing neutral particles produced in the heavy-ion collisions to contribute to the signal through conversion electrons. This paper discusses the design, operation and performance of the RXNP during the 2007 RHIC run.'
address:
- 'Physics Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA'
- 'University of Colorado, Boulder, Colorado 80309, USA'
- 'Columbia University, New York, New York 10027 and Nevis Laboratories, Irvington, New York 10533, USA'
- 'University Of Maryland, College Park, Maryland 20742, USA'
- 'Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA'
- 'RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, JAPAN'
- 'RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973-5000, USA'
- 'Chemistry Department, Stony Brook University, SUNY, Stony Brook, New York 11794-3400, USA'
- 'Department of Physics and Astronomy, Stony Brook University, SUNY, Stony Brook, New York 11794, USA'
- 'Institute of Physics, University of Tsukuba, Tsukuba, Ibaraki 305, Japan'
author:
- 'E. Richardson'
- 'Y. Akiba'
- 'N. Anderson'
- 'A.A. Bickley'
- 'T. Chujo'
- 'B.A. Cole'
- 'S. Esumi'
- 'J.S. Haggerty'
- 'J. Hanks'
- 'T.K. Hemmick'
- 'M. Hutchison'
- 'Y. Ikeda'
- 'M. Inaba'
- 'J. Jia'
- 'D. Lynch'
- 'Y. Miake'
- 'A.C. Mignerey'
- 'T. Niida'
- 'E. O’Brien'
- 'R. Pak'
- 'M. Shimomura'
- 'P.W. Stankus'
- 'T. Todoroki'
- 'K. Watanabe'
- 'R. Wei'
- 'W. Xie'
- 'W.A. Zajc'
- 'C. Zhang'
bibliography:
- 'rxnp\_nim.bib'
title: A reaction plane detector for PHENIX at RHIC
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Scintillator ,Paddle ,Reaction Plane ,Heavy-ions ,RHIC ,PHENIX
