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Flow and Bose-Einstein Correlations in Au-Au Collisions at RHIC. Steven Manly (Univ. of Rochester) For the PHOBOS Collaboration. Flow constitutes the bulk of this talk. Probe the source dynamics through correlations. Collaboration. - PowerPoint PPT Presentation
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July 18, 2002 S.Manly (PHOBOS) - QM2002 1
Flow and Bose-Einstein Correlations in Au-Au Collisions at RHIC
Probe the source dynamics through
correlations
Flow constitutes the bulk of this talk
Steven Manly (Univ. of Rochester)
For the PHOBOS Collaboration
July 18, 2002 S.Manly (PHOBOS) - QM2002 2
Collaboration
ARGONNE NATIONAL LABORATORYBirger Back, Alan Wuosmaa
BROOKHAVEN NATIONAL LABORATORY Mark Baker, Donald Barton, Alan Carroll, Nigel George, Stephen Gushue, George Heintzelman, Burt Holzman, Robert Pak, Louis Remsberg, Peter Steinberg, Andrei Sukhanov
INSTITUTE OF NUCLEAR PHYSICS, KRAKOWAndrzej Budzanowski, Roman Hołyński, Jerzy Michałowski, Andrzej Olszewski, Pawel Sawicki, Marek Stodulski, Adam Trzupek, Barbara Wosiek, Krzysztof Woźniak
MASSACHUSETTS INSTITUTE OF TECHNOLOGYMaartin Ballintijn, Wit Busza (Spokesperson), Patrick Decowski, Kristjan Gulbrandsen, Conor Henderson, Jay Kane, Judith Katzy, Piotr Kulinich, Jang Woo Lee, Heinz Pernegger, Corey Reed, Christof Roland, Gunther Roland, Leslie Rosenberg, Pradeep Sarin, Stephen Steadman, George Stephans, Carla Vale, Gerrit van Nieuwenhuizen, Gábor Veres, Robin Verdier, Bernard Wadsworth, Bolek Wysłouch
NATIONAL CENTRAL UNIVERSITY, TAIWANChia Ming Kuo, Willis Lin, Jaw-Luen Tang
UNIVERSITY OF ILLINOIS AT CHICAGORussell Betts, Edmundo García, Clive Halliwell, David Hofman, Richard Hollis, Aneta Iordanova, Wojtek Kucewicz, Don McLeod, Rachid Nouicer, Michael Reuter, Joe Sagerer
UNIVERSITY OF MARYLANDAbigail Bickley, Richard Bindel, Alice Mignerey,
Marguerite Belt Tonjes
UNIVERSITY OF ROCHESTERJoshua Hamblen, Erik Johnson, Nazim Khan, Steven Manly, Inkyu Park, Wojtek Skulski, Ray Teng, Frank Wolfs
July 18, 2002 S.Manly (PHOBOS) - QM2002 3
Elliptic flow
dN/d(R ) = N0 (1 + 2v1cos (R) + 2v2cos (2(R) + ... )
Determine to what extent the initial state spatial anisotropy is mapped into the final state particle production.
Sensitive to the degree of equilibration and the initial equation of state.
Affects other variables, such as HBT and spectra.
July 18, 2002 S.Manly (PHOBOS) - QM2002 4
Subevent technique: correlate qqqreaction plane in one part of qqqdetector to asymmetry in qqqtrack pattern in other part of qqqdetector
Correct for imperfect reaction plane resolution
-2.0 < < -0.1
SubE (a) SubE (b)
na n
b
0.1 < < 2.0
dependence of the multiplicity
Flow: basic method
July 18, 2002 S.Manly (PHOBOS) - QM2002 5
The PHOBOS Detector (2001 run)
137000 Silicon Pad Channels
1m
Spectrometer
Octagon
Vertex
Ring Counters
Paddle Trigger Counter
Cerenkov Counter
July 18, 2002 S.Manly (PHOBOS) - QM2002 7
RingsN Octagon RingsP
Flow: Hit-based method nucl-ex/0205021 submitted to PRL
Select vertices offset in z, symmetric coverage in ,
July 18, 2002 S.Manly (PHOBOS) - QM2002 8
RingsN Octagon RingsP
Reaction plane determined by subevents in -2<<2
Select vertices offset in Z, symmetric coverage in ,
Flow: Hit-based method nucl-ex/0205021 submitted to PRL
July 18, 2002 S.Manly (PHOBOS) - QM2002 9
RingsN Octagon RingsP
Reaction plane determined by subevents in -2<<2Elliptic flow (v2) determined for ||<5.3
Select vertices offset in Z, symmetric coverage in ,
Flow: Hit-based method nucl-ex/0205021 submitted to PRL
July 18, 2002 S.Manly (PHOBOS) - QM2002 10
Flow: Track-based New for QM2002!
Vertex measurement
Reaction plane determined by hits in widely separated subevent regions, symmetric in ,
July 18, 2002 S.Manly (PHOBOS) - QM2002 11
Reaction plane determined by hits in widely separated subevent regions, symmetric in ,
Correlate tracks in spectrometer to reaction plane to determine v2
Flow: Track-based New for QM2002!
July 18, 2002 S.Manly (PHOBOS) - QM2002 12
Hit-based analysis
• Large coverage
• Event-by-event
• Uniform acceptance in
• Separated subevents
Track-based analysis
• pt dependence
• Tracks less background sensitive
• Minimal MC dependence
• Subevents and tracks wwwidely separated in
• (Species dependence)
July 18, 2002 S.Manly (PHOBOS) - QM2002 13
v2 vs. centrality and energy
Preliminary v2200
Final v2130
Hit-based result v2200
& v2130 similar
PHOBOS Au-Au
130 GeV result: nucl-ex/0205021, submitted to PRL
||<1
200
130
v 2
<Npart>
July 18, 2002 S.Manly (PHOBOS) - QM2002 14
Hit and track-based results agree!
v2200 (hit)
v2200 (track)
PHOBOS Preliminary
200 GeV Au-Au
v2 vs. centrality, method comparison
||<1
trackhit
v 2
<Npart>
July 18, 2002 S.Manly (PHOBOS) - QM2002 15
v2 vs. pT
v2 appears to saturate for pT>2
Similar to published results at 130 GeV (STAR, PHENIX)
PHOBOS preliminary
h+ + h-
200 GeV Au-Au
track-weighted centrality averaging
0<<1.5
(top 55%)
v 2
17% scale error
July 18, 2002 S.Manly (PHOBOS) - QM2002 16
v2 vs. and energy
Preliminary v2200
Final v2130
Hit-based result
v2200 & v2
130 similar
PHOBOS Au-Au
130 GeV result: nucl-ex/0205021, submitted to PRL
v 2
200 130
<Npart>~190
July 18, 2002 S.Manly (PHOBOS) - QM2002 17
PHOBOS preliminary
200 GeV Au-Au
v 2
Unambiguous large drop in v2 over broad range in
v2 -dependence
July 18, 2002 S.Manly (PHOBOS) - QM2002 18
PHOBOS preliminary
200 GeV Au-Au
v 2
Unambiguous large drop in v2 over broad range in
v2 -dependence
Know pT, multiplicity, species yield vary with and all can affect flow
July 18, 2002 S.Manly (PHOBOS) - QM2002 19
Unambiguous large drop in v2 over broad range in
v2 -dependence
Know pT, multiplicity, species yield vary with and all can affect flow
PHOBOS preliminary
h+ + h-
200 GeV Au-Au
0<<1.5v 2
recall
July 18, 2002 S.Manly (PHOBOS) - QM2002 20
There is no large central plateau in the multiplicity distribution!
See talk by Mark Baker tomorrow morning and talk by Peter Steinberg in minutes in session I
dN
ch/d
’/<
Np
art>
Phobos
Systematic errors not shown
’=-ybeam
July 18, 2002 S.Manly (PHOBOS) - QM2002 21
Boost invariance
at RHIC
We look forward to seeing data() from BRAHMS!
?
July 18, 2002 S.Manly (PHOBOS) - QM2002 22
HBT
phase space Identified ’s
Another way to look at source dynamics ...
July 18, 2002 S.Manly (PHOBOS) - QM2002 24
HBT results
2222222 21 OLLOSSLLOO RQQRQRQRQeC
- - 0.540.02 5.80.2
5.10.4 6.80.3
Rout Rside Rlong
++ 0.570.03 4.90.4 7.30.3
5.80.2
R2out-long
4.91.74.51.9
Phobos preliminary
200 GeV Au-Au15% most central events
0.15<kT<0.35
0.2<y<1.5
Systematic error on radii of 1 fm, on of 0.06
July 18, 2002 S.Manly (PHOBOS) - QM2002 25
Scaling with energy -- data
For more on HBT at PHOBOS, see poster by C.M. KuoCompilation of non-PHOBOS data from C. Adler et al., Phys. Rev. Lett. 87, 082301 (2001)
July 18, 2002 S.Manly (PHOBOS) - QM2002 26
Summary/parting thoughts
v2200 is little changed from v2
130
AND ...
v2(pT) appears to saturate for pT>2 GeV/c
Rout, Rside, Rlong at 200 GeV are similar to those at 130 GeV
PHOBOS analyzing flow with hits and tracks
July 18, 2002 S.Manly (PHOBOS) - QM2002 28
An expert is a man who has made all the mistakes, which can be made, in a very narrow field.
- Niels Bohr, recalled on his death, November 1962
More to come fromP. Steinberg - Universal behavior of charged particle production
(session I, his talk is just starting … skip the QA and go!)M. Baker - Global observations from PHOBOS
Tomorrow morning (19th)
B. Wosiek - Identified particle pt distributions (including very low pt!) Parallel session I, tomorrow night (19th)
C. Roland - Scaling of charged hadron pt distributions Parallel session I, Saturday evening (20th)
C.M. Kuo - HBT Correlations (poster)
A. Iordanova - 20 GeV Au-Au analysis (poster)
R. Hollis - 200 GeV p-p analysis (poster)
:
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