JPS (Sep / 23 / 2000) at Niigata

Hadron production in
65AGeV Au + 65 AGeV Au collisions
at RHIC-PHENIX (1)Susumu SATO for PHENIX(Univ. of Tsukuba)

BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

PHENIX collaboration andJapanese Contributions
Japan:

CNS, Hiroshima, KEK,
Kyoto, Nagasaki
RIKEN, RIKEN BNL Res. Cent.,
TITech., Tokyo,
Tsukuba, Waseda

Korea: Korea, Myongji, Yonsei
Russia: IHEP Protvino, JINR Dubna,Kurchatov, PNPI, St. Petersburg STUBrazil:
Sao Paolo
Sweden: Lund
Canada:
McGillU.S. :(National Labs) BNL, LANL, LLNL, ORNL
China:
Academia Sinica, CIAE(Universities) Abilene Christian, AlabamaFrance:
SUBATECH
Huntsville, California-Riverside, Columbia,
Germany: Muenster
Florida State, Georgia State, IowaState,India:
BARC, Banaras Hindu University
New Mexico, New Mexico State, SUNYIsrael:
Weizmann Institute
Stony Book, Tennessee, Vanderbilt

Japan takes large roles among 12 nations (46 institutions )BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

Physics of hadron measurement with PID(1) Observation and characterization of QCD plasma (QGP).
Observables

distinctive feature of fireball

2nd rise of <pt>

1st order of phase transition into
hadronRout>>Rside

longer hadronization time

high-pt hadron production

reduced dE/dx of quarks in fireballchange of p-bar
productionchange in a baryon susceptibilitychange of width or/and
branching ratio for
φÆK+K-

different reaction inside the fireball

PID
makes constrains

stronger.

QGP?!
PIDisrequired.
( e/photon signal, muon signal, etc.)(2) Understanding of basic collision dynamics for heavy ion collisions at s1/2=130AGeV
change in transverse
kinetic energy spectrachange in temperature, flow, stopping,baryon density.

PID

change in particle ratiochange in thermodynamics

required.

BNL-RHIC-PHENIX

isBasic
Collision
Dynamics

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

PHENIX
Central Arm detectors
Beam axis cross section

Detector operated
in Year 2000

Bird view

SBBCW
ENTEC
Pc3(5 m)BNLBNL-RHICRHIC-PHENIX• Tracking + hadron PID (TOF)• e ID (RICH)• EMcal (PbSci,PbGl)• Vertex detector (MVD)
Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

Tracking devices in Central arm
Location (m)Technology# of Ch.

Performance

Drift Ch.
(DC)

2.02-2.46:(East & West)

Low mass
multiwire drift ch.

12.8 kµm
150µφ)(r-φ

Pad Ch.
(PC)

2.47 : (East, PC1)
4.15 : (West, PC2)
4.91 : (East, PC3)

pad readout

210 k

4 –8 mmφ)(z & r-φ

TimeExpansion Ch.
(TEC)

4.23-4.88 (East)

multisamplingdE/dx

43 k250 µmφ)(r-φ• DC is fundamental device for momentum reconstruction• TEC is for higher momentum reconstruction• PCs are for z-info, and pattern recognitions
BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

First detection of Au + Au collisions
at PHENIX
On Jun/15/ 2000.
Signals were recorded
simultaneously inseven PHENIX detectors
ZDC, BBC, TOF, PAD, DC,TEC, EMCal.
The event display showsreconstructed tracks pointing
to the collision.

BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

N hit (TOF)

N hit (PC3)

PC1/PC3/TOF correlation

N hit (PC1)

N hit (PC3) scaled• Clear correlation among PC1, PC3, and TOF.
BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

TEC/TOF matching

σ~120ps(without slewing correction)• Good matching with TEC tracking detector
BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

d y (cm)

TOF association with DC/PC1 tracking
Select in 2 σ radius

Searching window
withr = 5cm(2σσ in y [or r-φφ]
correlation)d z (cm)

d y (cm)

d z (cm)• Clear correlation between DC/PC1 track and TOF.
BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

Particle Identification by Time of Flight method

PHENIX preliminary
Corrections to be done:(1)Acceptance(2) Reconstruction efficiency(3) Slewing• Clear particle identification has been achieved !
BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

Mass square distribution
using Time-of-Flight method
PositiveParticle
All pNegativeParticle

p < 0.5
PHENIX preliminary
Corrections to be done:(1)Acceptance(2) Reconstruction efficiency(3) Slewing

0.5 < p < 0.80.8 < p < 0.9
0.9 < p < 1.0
1.0 < p < 1.1π+

K+

pπ−

K−

p1.1 < p < 1.2
1.2 [GeV/c] < p• Clear particle identification in high p region,
where Time-of-Flight method is required !

BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）

JPS (Sep / 23 / 2000) at Niigata

Summary• Tracking detectors (DC/PC1/TEC/PC3) andthe TOF at the PHENIX central arm
are demonstrated to be functioning
in the first RHIC operating year (Year-2000),
at 65 AGeV Au + 65 AGeV Au collisions.

• The magnetic spectrometer enables
the PIDed hadron physics at higher momentum region,
which is one of the distinctive advantages in PHENIX.

BNLBNL-RHICRHIC-PHENIX

Susumu SATO (Univ. ｏｆ Ｔｓｕｋｕｂａ）
Ｔｓｕｋｕｂａ）