Transversity: New Developments in Nucleon Spin Structure

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Transversity New Developments in Nucleon Spin
Structure
ECT, 13-18 June 2004
http//www.lnf.infn.it/conference/transversity04/
Introduction, theoretical overview D. Boer,
Amsterdam Transversity measurements at HERMES
Andy Miller, TRIUMF Transversity measurements at
COMPASS R. Joosten, Bonn Single Transverse Spin
Asymmetries at RHIC Chr. Aidala,
Columbia Transversity Hall-B at JLab Harut
Avagian, Newport News Transversity Hall-A at
JLab X. Jiang, Rutgers Open discussion on
experimental data plans Transversity
Properties of Quarks and Nucleons Leonard
Gamberg, Penn State Generalized parton
distributions Markus Diehl, DESY Lattice gauge
calculations Philipp Haeger, Amsterdam Single-spin
asymmetries in Drell-Yan and pion production
processes Umberto D'Alesio, Cagliari Quark
Correlations and Transverse single spin
asymmetries Matthias Burkardt, NMSU/ETC Transvers
e asymmetries and e(x) Peter Schweitzer,
Bochum T-odd transverse distributions Gary
Goldstein, Boston The Belle data M.
Grosse-Perdekamp, Urbana-Champaign Azimuthal
asymmetries John Collins, Penn State kT-dependent
distribution functions Dennis Sivers,
Portland Color gauge invariance Andreas Metz,
Bochum Color gauge invariance in hard processes
Fetze Pijlman, Amsterdam Extracting the Sivers
function using a purity method based ansatz Hide
Tanaka, Tokyo Single spin asymmetries ALU and AUL
calculated in a spectator diquark model Marc
Schlegel, Bochum Single spin azimuthal
asymmetries on longitudinal targets and the
Sivers effects Aram Kotzinian, CERN Single spin
asymmetries as probes of nucleon structure and
dynamics Dae Sung Hwang, Sejong, Seoul
Next Frascati 12-16 June 2006
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SIDISTheory

• Amsterdam group (Mulders,Boer,Pijlman..)
• Classifiacation of TMDs up to twist-3 (theory
  overview and developments)
• INFN (Anselmino,Kotzinian,DAlesio,Radici)
• Fenomenology of kT dependence for cross sections,
  asymmetries
• Bochum-Regensburg (Metz,Goeke,Bacchetta,Schweitzer
  )
• Universality,Sivers and Collins functions
• Collins (factorization,universality)
• BHS (Brodsky, Hwang,)
• FSI, relations between TMDs and GPDs
• Others (Penn State, Osaka,Peking,DESY..)
  (transversity,Sivers,twist-3)
• --------------------------------------------------
  -----------------------------------
• Mariland (Ji, Yuan, Ma,)
• Dubna (Efremov, Teryaev,..)

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Experiment

• (3510) Transversity measurements at HERMES Andy
  Miller, TRIUMF
• (3510)Transversity measurements at COMPASS R.
  Joosten, Bonn
• Single Transverse Spin Asymmetries at RHIC Chr.
  Aidala, Columbia
• Transversity Hall-B at JLab Harut Avagian,
  Newport News
• Transversity Hall-A at JLab X. Jiang, Rutgers
• Open discussion on experimental data plans

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Trento 2004 New data!
(sorry, only hall with a logo!)

• Universality questions are the new kT-dependent
  functions process-dependent or not?
• The new data do we have a qualitative
  understanding?
• Modelling toward a quantitative understanding
• Other avenues GPDs and Lattice QCD

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Experiment
0930 Welcome ECT chair Workshop chair 0945
(5010) Introduction, theoretical overview D.
Boer, Amsterdam 1045 Coffee break 1115
(3510) Transversity measurements at HERMES Andy
Miller, TRIUMF 1200 (3510) Transversity
measurements at COMPASS R. Joosten, Bonn 1245
Lunch break 1530 Coffee break 1600 (3010)
Single Transverse Spin Asymmetries at RHIC Chr.
Aidala, Columbia 1640 (3010) Transversity
Hall-B at JLab Harut Avagian, Newport News 1720
(3010) Transversity Hall-A at JLab X. Jiang,
Rutgers 1800 Open discussion on experimental
data plans
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Universality Questions
Are the kT-dependent distribution and
fragmentation functions process-dependent?
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p SSA from r
Modulation exist even for vanishing helicity
change amplitudes
r0
p SSA at large z may have a significant
contribution from r