EMCal resolution 450 ps
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EMCal resolution 450 ps Inclusive identified hadron spectra use TOF in East Arm ->K + K - uses TOF-TOF, EMCal-EMCal, and TOF-EMCal in East ->e + e - uses RICH, EMCal-EMCal in East-West, East-East, and West-West PHENIX Particle Identification for , K , and p /K Separation in TOF up to 2 GeV/c K/p Separation in TOF up to 4 GeV/c p Mixed Event Calculated Background Actual Pairs Fit to a Relativistic BW shape convolved with a 1.20 MeV Gaussian Note the 1 MeV mass binning Relativistic Breit-Wigner convolved with a 1.2 MeV Gaussian Signal Detected as K + K - Pairs in TOF-TOF Signal Detected as K + K - Pairs in TOF-EMCal 3) Measurements of the ->K + K - with PHENIX in Au+Au Collisions at 200 GeV at RHIC Charles F. Maguire Vanderbilt University (for the PHENIX collaboration) momentum resolution p /p ~ 1% 1% p TOF resolution 120 ps Final results for the Line Shape and the Yields of the Final results for the Line Shape and the Yields of the as a Function of Centrality as a Function of Centrality Combination of TOF-TOF, TOF-EMCal, and EMCal-EMCal Data: Combination of TOF-TOF, TOF-EMCal, and EMCal-EMCal Data: All Mutually Consistent All Mutually Consistent Mixed Event Calculated Background Actual Pairs Conclusions for the Yield in Au+Au Collisions at 200 GeV The yield per participant saturates as a function of centrality The Temperature is constant as a function of centrality Conclusions for the Mass Centroid of the in Au+Au collisions at 200 GeV Within the experimental error limits ( stat , stat < 1 MeV) the centroid mass value agrees with the PDG value and there is no dependence on the centrality of the collision Conclusions for the Mass Width of the in Au+Au collisions at 200 GeV Within the experimental error limits ( stat , stat < 0.5 MeV) the width value agrees with the PDG value and there is no dependence on the centrality of the collision The excellent single particle momentum resolution of the PHENIX spectrometer leads to a pair mass resolution of ~1.2 MeV, much less than the intrinsic width of the . The good pair mass resolution enables us to set narrow constraints on the line shape. R. Rapp nucl-th/0204003 Restoration of approximate chiral symmetry may modify the mass and width in medium Mass = 1019.456 +/- 0.020 MeV Breit-Wigner = 4.26 +/- 0.06 MeV Look for variations with centrality Compare to p+p and d+A results These modifications may result in a change in the branching fraction of K + K - and e + e - when the decays in medium ( ~ 44 fm/c) Compare different pair p T ranges Final state interactions of kaons may lower the apparent measured branching fraction of K + K - relative to e + e - Measure both channels in the same detector Theoretical Interest of the in Collisions at RHIC 1) 2) 4) 5)
description
Measurements of the f ->K + K - with PHENIX in Au+Au Collisions at 200 GeV at RHIC Charles F. Maguire Vanderbilt University (for the PHENIX collaboration). p / K Separation in TOF up to 2 GeV/c K/p Separation in TOF up to 4 GeV/c. PHENIX Particle Identification for , K , and p . - PowerPoint PPT Presentation
Transcript of EMCal resolution 450 ps
EMCal resolution 450 ps
Inclusive identified hadron spectra use
TOF in East Arm
->K+K- uses TOF-TOF, EMCal-EMCal, and TOF-EMCal in East
->e+e- uses RICH,EMCal-EMCal in
East-West, East-East, and West-West
PHENIX Particle Identification for , K, and p /K Separation in TOF up to 2 GeV/cK/p Separation in TOF up to 4 GeV/c
p
Mixed Event Calculated
Background
Actual PairsFit to a Relativistic BW shape
convolved with a 1.20 MeV Gaussian
Note the 1 MeV mass binning
Relativistic Breit-Wigner convolved with a 1.2 MeV Gaussian
Signal Detected as K+K- Pairs in TOF-TOF Signal Detected as K+K- Pairs in TOF-EMCal3)
Measurements of the ->K+K- with
PHENIX in Au+Au Collisions at 200
GeV at RHIC
Charles F. Maguire
Vanderbilt University
(for the PHENIX collaboration)
momentum resolution p/p ~ 1% 1% p
TOF resolution 120 ps
Final results for the Line Shape and the Yields of the Final results for the Line Shape and the Yields of the as a Function of Centrality as a Function of CentralityCombination of TOF-TOF, TOF-EMCal, and EMCal-EMCal Data: Combination of TOF-TOF, TOF-EMCal, and EMCal-EMCal Data: All Mutually ConsistentAll Mutually Consistent
Mixed Event Calculated
Background
Actual Pairs
Conclusions for the Yield in Au+Au Collisions
at 200 GeV
The yield per participant saturates as a function of
centrality
The Temperature is constant as a function of
centrality
Conclusions for the Mass Centroid ofthe in Au+Au collisions at 200 GeV
Within the experimental error limits (stat , stat < 1 MeV) the centroid mass
value agrees with the PDG valueand
there is no dependence onthe centrality of the collision
Conclusions for the Mass Width ofthe in Au+Au collisions at 200 GeV
Within the experimental error limits (stat , stat < 0.5 MeV) the width value
agrees with the PDG valueand
there is no dependence onthe centrality of the collision
The excellent single particle momentum resolution of the PHENIX spectrometer
leads to a pair mass resolution of ~1.2 MeV, much less than the intrinsic width of the .The good pair mass resolution enables us to set narrow constraints on the line shape.
R. Rapp nucl-th/0204003
Restoration of approximate chiral symmetry may modify the mass and width in medium
Mass = 1019.456 +/- 0.020 MeVBreit-Wigner = 4.26 +/- 0.06 MeV
Look for variations with centrality Compare to p+p and d+A results
These modifications may result in a change in the branching fraction of K+K- and e+e- when the decays in medium ( ~ 44 fm/c)
Compare different pair pT ranges
Final state interactions of kaons may lower the apparent measured branching fraction of K+K- relative to e+e-
Measure both channels in the same detector
Theoretical Interest of the in Collisions at RHIC
1) 2)
4)
5)
