transverse spin physics at rhic ii
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STAR. Transverse Spin Physics at RHIC II. Strong Interaction Physics at BNL RHIC RHIC II e-RHIC RHIC II Luminosity and Detector Upgrades Overview of the Physics Program Transverse Spin Physics Collins and Interference Fragmentation - PowerPoint PPT PresentationTRANSCRIPT
Transverse Spin Physics at RHIC II M. Grosse Perdekamp
University of Illinois and RIKEN BNL Research Center
QCD N06 , June 12 - 16, 2006, Rome, Italy
o Strong Interaction Physics at BNL
RHIC RHIC II e-RHIC
o RHIC II
Luminosity and Detector Upgrades Overview of the Physics Program
o Transverse Spin Physics
Collins and Interference Fragmentation Drell Yan
STARSTAR
pp2pppp2pp
Transverse Spin Physics at RHIC II 2 June 16th
Strong Interaction Physics at
o Quark Matter at high Temperatures and Densities
ion-ion collisions (Cu-Cu, Au-Au: √sNN=22.5, 62, 130, 200 GeV)
o Proton Spin Structure
polarized proton-proton collisions (p-p: √s=200 to 500 GeV)
o Low-x and high parton densities
ion-deuteron collisions (d-Au: √sNN=200 GeV)
very active field: 74 PRL letters in the first 5 years
high luminosity, detector upgrades
high luminosity, dedicated transverse spin experiment?
high luminosity, detector upgrades
polarized e-p
polarized e-p
RHIC IIe-RHICRHIC
RHIC II
Transverse Spin Physics at RHIC II 3 June 16th
Transverse spin program at RHIC is luminosity limited
AN yes, very good
AN(back-to-back) good
AT (Collins FF) fair
AT (Interference FF) limited
ATT (Jets) not studied experimentally
AT (Drell Yan) ---
ATT( Drell Yan) ---
Direct photons, Ws --- (AN,AT(CFF, IFF))
RHIC by 2009 at 200 GeV
∫Ldt ~275pb-1 delivered
∫Ldt ~100pb-1 accepted(eg. PHENIX: vertex cut,trigger efficiencies, dutyfactor)
∫Ldt ~25 pb-1 transverse
RH
IC II
Physics channel Luminosity?
Dedicated Drell Yan experiment for transverse spin physics at RHIC ?
Transverse Spin Physics at RHIC II 4 June 16th
(I) Electron Cooling in RHIC to increase luminosity for HI by factor 10
(II) Detector Upgrades in PHENIX and STAR
(III) Drell Yan Experiment for Transverse Spin?
RHIC II – Definition
RHIC II upgrades will be carefully coordinated with the effort to build a electron ion collider RHIC as “QCD Lab”
target date 2012
Transverse Spin Physics at RHIC II 5 June 16th
RHIC II: Luminosity Upgrade with Electron Cooling (from Thomas Roser)
Transverse Spin Physics at RHIC II 6 June 16th
• Factor 2-3 increase in pp luminosity
• Small improvements in polarization
• Maximum energy √s = 650 GeV
• Operation at 20-30% higher energy possible
• Can have polarized 3He2+ beams
• Mini-quads at one IP can boost luminosity by a factor 3-5
assume factor 10 possible with mini-quads, if mini-
quads can be integrated with detector design!
p-p Expectations for the RHIC II Luminosity Upgrade
Transverse Spin Physics at RHIC II 7 June 16th
RHIC five complementary experiments
RHIC II: Room for New Ideas!
pp2pppp2pp100% transverse !
Transverse Spin Physics at RHIC II 8 June 16th
RHIC II: Upgrades in STAR and PHENIX
FMS (Forward Meson Spectrometer)
TOF HFT (Heavy Flavor Tracker)
Tracking UpgradeDAQ
HBD (Hadron Blind Detector)
Silicon (VTX, FVTX)Muon TriggerForward Calorimeter
T-SPHINX
RHIC II: Transverse Spin Physics High Rate (N) Experiment
Transverse Spin Physics at RHIC II 9 June 16th
T-SPHINX
RHIC II: Transverse Spin Physics High Rate (N) Experiment
Large acceptance Drell Yan experiment:
(1) 100 % Transverse Spin x 4 (2) Large acceptance -3<η<+3 x 8 (3) Electron cooling x 2.5 (4) Mini-quads x 4 ~300Physics: Sivers-, Transversity-, Boer-Mulder-distributions in Drell Yan lepton pair production at RHIC.
Relative gain in ∫LdtCompared to PHENIX
Transverse Spin Physics at RHIC II 10
June 16th
Luminosity upgrade
High statistics Au-Au, 500 GeV pp RHIC II
RHIC II Schedule: Detector Upgrades + Luminosity
Transverse Spin Physics at RHIC II 11
June 16th
RHIC II Science Workshops: Spin Physics
Transverse spin physics: S. Menzel (Bochum), L. Gamberg (Penn State), J. Soffer (Marseille), M. Burkardt (New Mexico), F. Yuan (RBRC), M. Radici (Pavia)
Hyperons : Z. Liang (Shandong), Q. Xu (Shandong+LBL), K. Sudoh (KEK)
W-physics: P. Nadolsky (Argonne), K. Sudoh (KEK), J. Soffer (Marseille)
Beyond the SM: J. Soffer (Marseille), D. Maitre (Zurich)
BNL, October 7-8, 2005
Science at RHIC II report: Summer 2006
Transverse Spin Physics at RHIC II 12
June 16th
Physics Channels for RHIC II
Precision measurement of the proton helicity structure
o ∆G(x) and ∆q(x), ∆q(x) with high luminosity in multiple channels with available detector upgrades. Extend measurements to 3He neutron. (can this be done with high polarization + intensity??) minimize errors and increase x-coverage of ∆G(x) for precision measurement of the first moment of the spin-dependent gluon distribution ∆G=ʃ ∆G(x)dx.
observe scale evolution of the first moment.
global QCD analysis for best knowledge of polarized nucleon structure + pdfs
Precision cross section measurements + QCD analysis
o Measure cross sections in direct photon production, inclusive jet + hadron production as input to QCD analysis to improve knowledge of
G(x) at large x Gluon fragmentation function
(RHIC II Spin Working Group, E. Sichterman, M. Stratmann, MGP, et al.)
Transverse Spin Physics at RHIC II 13
June 16th
Physics Channels for RHIC II
Polarization of the strange sea o Access ∆s(x) through inclusive anti-Lambda production and charm associated W-production (very luminosity hungry!) study polarization of the strange sea verify ∆s from DIS
Transverse Spin Physics o Extract transversity quark distributions from precision measurements of asymmetries in Collins- and interference fragmentation. o Measure transversity-, Sivers- and Boer-Mulders asymmetries in Drell Yan. AN in direct photon and W production.
Transverse Spin Physics at RHIC II 14
June 16th
Transversity from Interference Fragmentation(Efremov, Collins, Heppelman, Ladinsky,
Atru, Jaffe, Jin, Tan, Radici, Jacob, Bacchetta)
NN
NN
PA
beamT
1
Func.tion Fragmenta Pol.: )(ˆ
quark DFsty Transversi : )(
d Pair Yiel Pion:
zq
xq
N
QCD analysis of Belle IFF and RHICAT in IFF to extract transversity
Transverse Spin Physics at RHIC II 15
June 16th
Projected statistical errors in one invariantmass bin 800 MeV < m < 950 MeV
Integrated Luminosity for RHIC II ~ 125 pb-1
pair vsAsymmetry on iesUncertaint Tp
1%
2%
IFF from BelleAT from STAR+PHENIX
Transverse Spin Physics at RHIC II 16
June 16th
Transversity : correlation between transverse proton spin and quark spin
Sivers : correlation between transverse proton spin and quark transverse momentum
Boer/Mulders: correlation between transverse quark spin and quark transverse momentum
Drell Yan Physics with T-SPHINX
)()( 21 xqxqATT
M
SkPkxfxqA PTq
TT
)ˆ(
),()( 2211
M
SkPkxh
M
SkPkxhN qqqq
)ˆ(),(
)ˆ(),()( 2
212
11
Transverse Spin Physics at RHIC II 17
June 16th
Sivers-Asymmetries, AT in Drell Yan (J. Collins et al.)
Sensitivity to anti-quark Sivers distribution (not probed at GSI)
Sensitivity to sign with respect to DIS!
Transverse Spin Physics at RHIC II 18
June 16th
Sivers-Asymmetries, AT in Drell Yan (J. Collins et al.)
STAR for 125pb-1
T-SPHINX1250 pb-1
o 10 o’clock 100% transverse polarization
o mini-quads
o acceptance: -3 < η < 3
x 300 in ∫Ldt
AT
Q=4GeV Q=20GeVQ=4GeV Q=20GeVAT
Precision measurement of Sivers distributions!
Transverse Spin Physics at RHIC II 19
June 16th
Projections for pp at 200 GeV and 1250 pb-1
ATT for Drell Yan with dedicated DY detector
projections for 1250pb-1 of running,5-10% higher polarization, with RHIC II luminosities and large acceptance
Drell Yan1.25fb-1, large acceptance detector for Drell Yan
This measurement appears to bealso possible at 500 GeV
Transverse Spin Physics at RHIC II 20
June 16th
RHIC II Summary
o Precision measurements of asymmetries in Collins- and Interference-Fragmentation to map out quark transversity distributions.
o Drell Yan
AT (a) STAR can test expected sign change for the Sivers function at low invariant mass.
(b) Dedicated DY experiment possible to extract Sivers quark distribution. Sensitive to anti- quark distributions!
ATT Clean measurement of anti-quark and possibly quark transversity distributions
o Access to Ws and direct photons.