Presentation is loading. Please wait.

Presentation is loading. Please wait.

Experimental Study of Transversity

Published byMagnhild Corneliussen Modified over 6 years ago

Similar presentations

Presentation on theme: "Experimental Study of Transversity"— Presentation transcript:

1 Experimental Study of Transversity
Lattice QCD and Experiment: Revealing the Structure of Hadrons Jefferson Laboratory, November 21 & 22, 2008 M. Grosse Perdekamp, University of Illinois

2 Experimental Study of Transversity
Content A brief history and first transversity extraction from data Connection with lattice: tensor charge Transversity in transverse momentum dependent (TMD) processes Transversity in transverse moment independent processes November 22 nd Experimental Study of Transversity

3 Experimental Study of Transversity
Transverse Spin Phenomena in Hard Scattering QCD QCD: Asymmetries for transverse spin are small at high energies (Kane, Pumplin, Repko, PRL 41, 1689–1692 (1978) ) Experiment (E704, Fermi National Laboratory): π+ QCD Test ! π0 π- November 22 nd Experimental Study of Transversity

4 Experimental Study of Transversity
Single Transverse Spin Asymmetries AN persist at √=62.4 GeV and 200 GeV √s=200 GeV STAR √s= PHENIX and BRAHMS AN AN STAR xF Large single spin asymmetries persist at higher √s=62.4 and 200 GeV xF November 22 nd Experimental Study of Transversity

5 Inspect Factorized Expression for Cross Section
fragmentation process Proton Structure Can initial and/or final state effects generate large transverse spin asymmetries? (ALL ~10-1) Jet hard scattering reaction pQCD Proton Structure small spin dependence (aLL~10-4) fragmentation function November 22 nd Experimental Study of Transversity

6 Experimental Study of Transversity
Transverse Spin in QCD: Two Solutions (I) “Transversity” quark-distributions and Collins fragmentation Correlation between proton- und quark-spin and spin dependent fragmentation AN π+ π0 Quark transverse spin distribution Collins FF π- (II) Sivers quark-distribution Correlation between proton-spin and transverse quark momentum xF Sivers distribution November 22 nd Experimental Study of Transversity

7 Experimental Study of Transversity
(I)-a Quark Transversity Distributions proton spin q quark with transverse spin in the final state! gluon probe quark spin Transversity quark distributions For a proton with spin direction transverse to the probe momentum: probability to find a quark with spin parallel to the proton spin minus “ “ “ spin anti-parallel “ “ November 22 nd Experimental Study of Transversity

8 Experimental Study of Transversity
(I)-b Collins Effect in the Quark- fragmentation in the Final State q sq π q NR : pions to the right Collins Effect NL : pions to the left Collins Effect: Fragmentation of a transversely polarized quark q into spin-less hadron h carries an azimuthal dependence: = 0 AN = NL - NR NL + NR November 22 nd Experimental Study of Transversity

9 Experimental Study of Transversity
The Collins Effect Must be Present In Semi-Inclusive Deep Inelastic Lepton Proton! quark with transverse spin in the final state followed by Collins effect in the quark fragmentation proton spin q photon probe quark spin November 22 nd Experimental Study of Transversity

10 Experimental Study of Transversity
First Observation of the Collins Effect in Polarized Deep Inelastic Electron-Proton Scattering HERMES Collins Asymmetries in semi- inclusive deep inelastic scattering e+p  e + π + X ~ Transversity (x) x Collins(z) AUT sin(f+fs) November 22 nd Experimental Study of Transversity

11 Experimental Study of Transversity
The Collins Effect Must be Present In e+e- Annihilation into Quarks! electron q1 q2 quark-1 spin quark-2 spin Collins effect in e+e- Quark fragmentation will lead to effects in di-hadron correlation measurements! positron November 22 nd Experimental Study of Transversity

12 Observation of the Collins Effect in e+e- Annihilation with Belle
Belle (UIUC/RBRC) group Collins Asymmetries in e+e- annihilation into hadrons e++e-  π+ + π- + X ~ Collins(z1) x Collins (z2) PRELIMINARY j2-p e- Q j1 e+ A12 cos(f1+f2) November 22 nd Experimental Study of Transversity

13 Extraction of Quark Transversity Distributions
and Collins Fragmentation Functions SIDIS + e+e- √s=10 GeV e++ e-  π+ + π- +X Program: QCD analysis of Collins asymmetries in SIDIS (HERMES & COMPASS) + Collins asymmetries in e+e- (Belle)  extract quark transversity distributions and Collins fragmentation functions 27.5 GeV e+p  π + X 160 GeV μ+d  π + X November 22 nd Experimental Study of Transversity

14 Extraction of Quark Transversity Distributions
and Collins Fragmentation Functions SIDIS + e+e- Fit includes: Soffer Bound HERMES SIDIS New fit + COMPASS SIDIS Old fit + Belle e+e- Old fit New fit  transversity dist. + Collins FF Anselmino, Boglione, D’Alesio, Kotzinian, Murgia, Prokudin, Turk and Melis at Transversity 2008, Ferrara. Previously: Phys. Rev. D75:05032,2007 November 22 nd Experimental Study of Transversity

15 Experimental Study of Transversity
Prokudin et al. at Ferrara November 22 nd Experimental Study of Transversity

16 Experimental Study of Transversity
Prokudin et al. at Ferrara Prokudin et al. at Ferrara November 22 nd Experimental Study of Transversity

17 Experimental Study of Transversity
Prokudin et al. at Ferrara November 22 nd Experimental Study of Transversity

18 Transversity Extraction + Tensor Charge with Collins FF
Done: We solved the (transversity) proton spin problem! ? Theory Lattice QCD: Tensor Charge November 22 nd Experimental Study of Transversity

19 Cross Checks with Different Targets: (I) proton-target at COMPASS
Preliminary COMPASS Collins Asymmetries for Proton Target vs predictions from Anselmino et al. Stefan Levorato at Transversity 2008, Ferrara 20% of collected data have been used. Futher analysis in progress! Good agreement of COMPASS proton data with preditions from fit to HERMES, Belle and COMPASS-d! November 22 nd Experimental Study of Transversity

20 Experimental Study of Transversity
Cross Checks with Different Targets: (II) 3He-target at JLab, E06-010/06-011 Projected Collins Asymmetries for 3He Target vs predictions from Vogelsang & Yuan Spokespersons: X. Jiang (Los Alamos) J.P. Chen (JLab) E. Cisbani (INFN) H. Gao (Duke) J.-C. Peng (UIUC) First 6 GeV JLab neutron (3He) measurement presently taking data! November 22 nd Experimental Study of Transversity

21 Can we gain a consistent description of the original AN asysmmetries?
Work in progress: complete analysis of SIDIS (Collins & Sivers) + e+e- (Collins) + pp AN (Collins & Sivers) Anselmino et al. Note: impact of unpolarized FFs thick line DSS thin line Kretzer November 22 nd Experimental Study of Transversity

22 Experimental Study of Transversity
Collins Extraction of Transversity: model dependence from Transverse Momentum Dependences! transversity Collins FF hadron FF quark pdf k┴ transverse quark momentum in nucleon p┴ transverse hadron momentum in fragmentation Anselmino, Boglione, D’Alesio, Kotzinian, Murgia, Prokudin, Turk Phys. Rev. D75:05032,2007 The transversse momentum dependencies are unknown and difficult to obtain experimentally! November 22 nd Experimental Study of Transversity

23 Future measurement of kT- (PDFs) and pT- (FFs) dependencies
(I) pT dependence of Collins and the unpolarized fragmentation functions can be measured with present data sample at Belle (1.5 Billion hadronic events). Super KEK-B will have 50 x more luminosity! (II) pT dependence of Collins effect can be also measured with high precision at JLab 12 GeV, later at EIC. Need ideas to get at the kT dependence of pdfs using The pT dependence from e+e-! 12 GeV - solenoid November 22 nd Experimental Study of Transversity

24 Sudakov Suppression of TMDs
Convolution integral sensitive to soft factor that leads to (Sudakov)_ suppression of Collins asymmetries ~ 1/√Q in SIDIS ~ 1/Q in e+e D. Boer Nucl. Phys. B (2001) Convolution in SIDIS can be avoided by weighted integration in SIDIS. However, not possible in in e+e- ! November 22 nd Experimental Study of Transversity

25 Experimental Study of Transversity
Measurements of transversity with transverse momentum independent functions !! Drell Yan  req. polarized anti-protons need to improve systematics on rel. luminosity need Lambda-FF  e+e- need Lambda-FF  e+e- need IFF  e+e- need IFF  e+e- November 22 nd Experimental Study of Transversity

26 First IFF Asymmetries in Hermes and COMPASS
data all +/- pairs preliminary proton target A. Bacchetta, M. Radici hep-ph/ model calculations proton HERMES kin deuteron COMPASS kin November 22 nd Experimental Study of Transversity

27 Experimental Study of Transversity
Transversity Quark Distributions at RHIC: Di-Hadron “Interference Fragmentation Functions IFF Asymmetries in proton-proton collisions p+p  π+ + π- + X ~ Transversity (x) x IFF(z)  k┴, p┴ integrate out Ongoing work: AT in PHENIX IFF in Belle November 22 nd Experimental Study of Transversity

28 First PHENIX Results on IFF Asymmetries for Pion Pairs
Ruizhe Yang, Transverse Spin Workhop in Beijing, July 2008 Expect small asymmetries at mid-rapidity (Bachetta et al.) More statistics is on tape. Need to move measure- ment forward! Systematic errors Polarization 5% Relative lumi. 5x10-4 No systematic effects detected from bunch shuffling Consistent with 0, despite the second bin of p0h- pairs and the last bin of h+h- pairs are 2s from 0 November 22 nd Experimental Study of Transversity

29 Experimental Study of Transversity
Projections for IFF measurement at BELLE j2-p p-j1 e+ e- thrust axis IFF sensitivity projection from data Artru and Collins, Z. Phys. C69, 277 (1996) Boer, Jakob, and Radici, PRD67, (2003) November 22 nd Experimental Study of Transversity

30 Measurements of quark transversity
Courtesy Ruizhe Yang 1991 Underway Future p+p RHIC Collins in jets E704, 1991 Large forward SSA STAR, PHENIX, BRAHMS Inclusive AN RHIC IFF asym. JParc, FAIR Drell-Yan HERMES COMPASS AUT SIDIS COMPASS p target JLab 3He JLab 12 GeV Collins, IFF EIC Collins in jets e++e- BELLE Collins FF BELLE IFF BELLE pT dependence November 22 nd Experimental Study of Transversity

31 Experimental Study of Transversity
Summary First measurements of transversity quark distributrions are available. TMD dependence of Collins function makes theoretical interpretation difficult. Knowledge of pT and (?) kT dependence may come from future measurements in e+e- and SIDIS. Non-TMD processes are available. Within the next few years measurements using di-hadron interference fragmentation functions will be available. We can aim to extract the tensor charge in a theoretically clean way and compare to lattice QCD! November 22 nd Experimental Study of Transversity

Download ppt "Experimental Study of Transversity"

Similar presentations

Fisica dello Spin27 Settembre 2005, Otranto1 Surprises: Transverse Single Spin Asymmetries (unintegrated polarized parton distributions) Single Spin Asymmetries.

Fisica dello Spin27 Settembre 2005, Otranto1 Surprises: Transverse Single Spin Asymmetries (unintegrated polarized parton distributions) Single Spin Asymmetries.
1 Como, September 7, 2005 Aram Kotzinian Cahn and Sivers effects in the target fragmentation region of SIDIS Introduction Hadronization in SIDIS Cahn and.

1 Como, September 7, 2005 Aram Kotzinian Cahn and Sivers effects in the target fragmentation region of SIDIS Introduction Hadronization in SIDIS Cahn and.
1 Transversity Physics Update Jen-Chieh Peng Polarized 3 He and Tansversity Collaboration Meeting, JLab, October 21-22, 2005 University of Illinois at.

1 Transversity Physics Update Jen-Chieh Peng Polarized 3 He and Tansversity Collaboration Meeting, JLab, October 21-22, 2005 University of Illinois at.
Mauro Anselmino, Torino University and INFN, Vancouver, July 31, 2007 The transverse spin structure of the nucleon.

Mauro Anselmino, Torino University and INFN, Vancouver, July 31, 2007 The transverse spin structure of the nucleon.
Transversity and Transverse-Momentum-Dependent Partonic Functions Alessandro Bacchetta.

Transversity and Transverse-Momentum-Dependent Partonic Functions Alessandro Bacchetta.
June 21, 2005 RHIC & AGS USER MEETING-SPIN 1 (Single) Transverse Spin Physics -- from DIS to hadron collider Feng Yuan, RBRC, Brookhaven National Laboratory.

June 21, 2005 RHIC & AGS USER MEETING-SPIN 1 (Single) Transverse Spin Physics -- from DIS to hadron collider Feng Yuan, RBRC, Brookhaven National Laboratory.
QCD N06 - Monte Porzio Catone - 15/06/2006 1 SIDIS Cross Sections and Spin Asymmetries Predictions for Ongoing and Future Experiments M.Elena Boglione.

QCD N06 - Monte Porzio Catone - 15/06/ SIDIS Cross Sections and Spin Asymmetries Predictions for Ongoing and Future Experiments M.Elena Boglione.
Mauro Anselmino, Prague, August 1, 2005 Hadron Structure and Hadron Spectroscopy Transversity (transverse spin and transverse motion) Transversity distributions.

Mauro Anselmino, Prague, August 1, 2005 Hadron Structure and Hadron Spectroscopy Transversity (transverse spin and transverse motion) Transversity distributions.
Constraining the polarized gluon PDF in polarized pp collisions at RHIC Frank Ellinghaus University of Colorado (for the PHENIX and STAR Collaborations)

Constraining the polarized gluon PDF in polarized pp collisions at RHIC Frank Ellinghaus University of Colorado (for the PHENIX and STAR Collaborations)
1 Updates on Transversity Experiments and Interpretations Jen-Chieh Peng Transversity Collaboration Meeting, JLab, March 4, 2005 University of Illinois.

1 Updates on Transversity Experiments and Interpretations Jen-Chieh Peng Transversity Collaboration Meeting, JLab, March 4, 2005 University of Illinois.
Overview on Transverse Momentum Dependent Distribution and Fragmentation Functions M. Boglione.

Overview on Transverse Momentum Dependent Distribution and Fragmentation Functions M. Boglione.
1 Transverse Spin Measurements at PHENIX John Koster for the PHENIX collaboration University of Illinois at Urbana-Champaign DIS2009 2009/04/27.

1 Transverse Spin Measurements at PHENIX John Koster for the PHENIX collaboration University of Illinois at Urbana-Champaign DIS /04/27.
Fragmentation Functions at Belle Anselm Vossen (University of Illinois) Matthias Grosse Perdekamp (University of Illinois) Martin Leitgab (University of.

Fragmentation Functions at Belle Anselm Vossen (University of Illinois) Matthias Grosse Perdekamp (University of Illinois) Martin Leitgab (University of.
Zhongbo Kang Los Alamos National Laboratory QCD structure of the nucleon and spin physics Lecture 5 & 6: TMD factorization and phenomenology HUGS 2015,

Zhongbo Kang Los Alamos National Laboratory QCD structure of the nucleon and spin physics Lecture 5 & 6: TMD factorization and phenomenology HUGS 2015,
Jim Stewart DESY Measurement of Quark Polarizations in Transversely and Longitudinally Polarized Nucleons at HERMES for the Hermes collaboration Introduction.

Jim Stewart DESY Measurement of Quark Polarizations in Transversely and Longitudinally Polarized Nucleons at HERMES for the Hermes collaboration Introduction.
Single-Spin Asymmetries at CLAS  Transverse momentum of quarks and spin-azimuthal asymmetries  Target single-spin asymmetries  Beam single-spin asymmetries.

Single-Spin Asymmetries at CLAS  Transverse momentum of quarks and spin-azimuthal asymmetries  Target single-spin asymmetries  Beam single-spin asymmetries.
Strangeness and Spin in Fundamental Physics Mauro Anselmino: The transverse spin structure of the nucleon Delia Hasch: The transverse spin structure of.

Strangeness and Spin in Fundamental Physics Mauro Anselmino: The transverse spin structure of the nucleon Delia Hasch: The transverse spin structure of.
Transverse Spin Physics at RHIC M. Grosse Perdekamp (University of Illinois and RBRC) International Workshop on Semi-Inclusive Reactions and 3D-Parton.

Transverse Spin Physics at RHIC M. Grosse Perdekamp (University of Illinois and RBRC) International Workshop on Semi-Inclusive Reactions and 3D-Parton.
1 Probing Spin and Flavor Structures of the Nucleon with Hadron Beams Flavor and spin structures of the nucleons –Overview and recent results Future prospects.

1 Probing Spin and Flavor Structures of the Nucleon with Hadron Beams Flavor and spin structures of the nucleons –Overview and recent results Future prospects.
JPARC DY Workshop, April 7 Ralf Seidl (RBRC) R.Seidl: Transverse Spin 1RIKEN, April 7 In JPARC Drell Yan accessible with: UU(unpolarized beam, unpolarized.

JPARC DY Workshop, April 7 Ralf Seidl (RBRC) R.Seidl: Transverse Spin 1RIKEN, April 7 In JPARC Drell Yan accessible with: UU(unpolarized beam, unpolarized.

Similar presentations

Ads by Google