detector requirement form tmd working group j. p. chen for the tmd working group june 5, 2010, eic...
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Detector requirement form TMD working groupJ. P. Chen for the TMD working group
June 5, 2010, EIC Detector Workshop, JLab
• TMD Program - A lot of enthusiasm, very rich physics - Beyond 1-d leading-twist distributions
- Direct link with orbital motion (orbital angular momentum) - Transverse motion: spin-orbit correlations, multi-parton correlations, dynamics of confinement and QCD - Transverse structure -> multi-dimension - Valence, Sea and Gluon - Consensus: “flagship/golden” program for MEIC
Thanks to Haiyan Gao, Min Huang, Xin Qian, … for slides/simulations.
Briefing on Talks from Duke Workshop
• Jianwei Qiu: L sensitive to short-d fluctuations, T sensitive to structure low PT and high PT, factorization, evolution (Kang),
Tri-gluon correlations, D-meson production->L g (Gluon OAM)• Daniel Boer: jet SIDIS, Sivers (no fragmentation) Sudakov suppression (need large Q2 range) • Mauro Anselmino: Model, <kT>, <pT> EMC data • Naomi Makins: HERMES, K+ asymmetry >+ @ low z !• Ming-Xiong Liu: RHIC-spin, K- asymmetry ~ K+ !, > 0
• Yi Qiang: n/3He@Hall A, 6 GeV/12 GeV, valence, 4-d mapping• Marco Contalbrigo: f1/g1 PT dep. diff., CLAS12: unpol, long. • Alexei Prokudin: sea Sivers also important, sqrt(s)=20, 65, PT to 5. • Leonard Gamberg: soft factor, Sivers-GPD(E) diff mother• Bernhard Musch: Gauge link on Lattice, no T-odd, cut-off, s-factor • Yuhong Zhang: MELIC design, options (3 curves), people like the option with
high luminosity for wide range of s • Simulations: Harut Avagyan, Min Huang
“Leading-Twist” TMD Quark Distributions
Quark
Nucleon
Unpol.
Long.
Trans.
Unpol. Long. Trans.
J.P. Chen, GDH, Chiral06 4
6 GeV Preliminary Results
12 GeV: 3-D Projections for Collins and Sivers Asymmetry (+)
Simulations for EIC SIDIS
• Simulations of phase space and projections in 4-d (x,z,PT,Q2) (done by Min Huang/Xin Qian)• Choose transverse nucleon single spin asymmetries as example - /K: simulations checked - D mesons: a new simulation, preliminary results
Needs MEIC with broad range of s and high L (>1034) Detector requirements, PID very important
SIDIS @ Electron Ion Collider
qP
PPz
PP
qPy
qP
Qx
p
hp
iep
p
p
2
2
q
qpP hh
S
h
Ion-at-rest frame
(Trento convention)
Lab Frame sPP
yx
Q iep
2
2
syxQ 2
Applied Cuts for DISElectron: 2.5°< ϴ < 150°P > 1.0 GeV/cFull azimuthal-angular coverageDIS cut: Q2 > 1 Large W cuts
0.8 > y > 0.05
Capability to detect high momentum electronNo need to cover very forward angle for electron
Applied Cuts for SIDIS
Hadron: 40°< ϴ < 175° 0.7 GeV/c < P < 10 GeV/cFull azimuthal-angular coverageLow momentum, large polar angluar coverage
SIDIS cut: Large MX cuts 0.8 > z > 0.2Low PT kinematics PT < 1.0 GeV/c
High PT kinematics PT > 1.0 GeV/c
10
Mapping of TSSA
Lower y cut, more overlap with 12 GeV
0.05 < y < 0.8
12 GeV: from approved SoLID SIDIS experiment
11
Study both Proton and Neutronion momentum
z
PN Z/A
Flavor separation, Combine the datathe lowest achievable x limited by the effective neutron beam
Cross Section in MCLow PT cross section:
A. Bacchetta hep-ph/0611265 JHEP 0702:093 (2007)
High PT cross section:M. Anselmino et al. Eur. Phys. K. A31 373 (2007)
2 hH dPdddzdydx
d
hhhfe
fe
fe dddpdddp
d
cos cos
• PDF: CTEQ6M• FF: Binneweis et al PRD 52 4947• <pt
2> = 0.2 GeV2 <kt2> = 0.25 GeV2
• NLO calculation at large PT
– <pt2> = 0.25 GeV2
– <kt2> = 0.28 GeV2
– K factor assumed to be larger than 1.
6x6 Jacobian calculation
Calculation InformationCalculation code is from Ma et al. (Peking
University)PDF: MRST 2004FF: Kretzer’s fit EPJC 22 269 2001Collins/Pretzelosity: PRD 054008 (2009)
PT dependence: Anselmino et al arXiv: 0807.0173Sivers TMD: Anselmino et al arXiv: 0807.0166Collins Fragmentation function: Anselmino et al 0807.0173
Q2 =10 GeV2
S: 11 GeV + 60 GeV
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Projection with Proton• 11 + 60 GeV 36 days L = 3x1034 /cm2/s 2x10-3 Q2<10 GeV2
4x10-3 Q2>10 GeV2
• 3 + 20 GeV 36 days L = 1x1034/cm2/s 3x10-3 Q2<10 GeV2
7x10-3 Q2>10 GeV2
Polarization 80%Overall efficiency 70%
z: 12 bins 0.2 - 0.8PT: 5 bins 0-1 GeV
φh angular coverage consideredShow the average of Collins/Sivers/Pretzlosity projections Also π-
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Projection with 3He (neutron)• 11 + 60 GeV 72 days• 3 + 20 GeV 72 days • 12 GeV SoLid
3He: 86.5% effective polarization Dilution factor: 3
D: 88% effective polarization Effective dilution
Equal stat. for proton and neutron (combine 3He and D)
8
11 + 60 GeV 3 + 20 GeV
P 36 d (3x1034/cm2/s) 36 d (1x1034/cm2/s)
D 72 d 72 d3He 72 d 72 d
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Proton π+ (z = 0.3-0.7)
Proton K+ (z = 0.3-0.7)
High PT kinematics
High PT : hadron momentum dramatically increase require high momentum PID, large polar angular coverage
PT dependence (High PT) on p of π+ 10 bins 1 -- 10 GeV in log(PT
)
Simulation (results still preliminary)Use HERMES Tunes Pythia (From H. Avagyan)First try 11+60 configuration.Physics includes:
VMDDirectGVMDDIS (intrinsic charm)
This is what we want!!
Event GeneratorQ2: 0.8-1500y: 0.2-0.8LUND Fragmentation.Major decay channel of D meson are
)()()(
)()()(0
0
suKduucD
usKduucD
Branching ratio: 3.8+-0.07%
PT >1.0 cut will remove most of events from VMD and DIS.
GVMD is a significant background.
At high Q2, the GVMD will be smaller.
D meson
Z>0.4Q2>2.0
Need low momentum and forward angle coverage.
Summary on detector requirements from TMD simulation
Large angular coverage, but no need the extreme “forward” / “backward” angular coverage for electrons/hadrons
Scattered electron Resolution and PID at high momentum
Leading hadron momentum large momentum range 0.5-1 GeV to 5-6 GeV/c, higher for high PT,
Good PID: kaons/pionsLarge polar angular coverageGood resolution
High Luminosity (in a wide range of s) essential to achieve precise mapping of SSAs in 4-D projection.