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Delia Hasch TMDs & friends from lepton scattering -experimental overview- INT workshop on “3D parton structure of the nucleon encoded in GPDs & TMDs”, Seattle, Sept. 14-18 2009 outline: introduction: some reminders… status Sivers DF Collins DF azimuthal dependence of unpolarised xsection the ‘soon to come’ menu

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experimental prerequisites 190 GeV ≈6 GeV e 27 GeV e till 2007 HALL A longitudinally polarised d long.+transv. polarised p ~full hadron ID CLAS: long. polarised effective p HallA: long.+transv. polarised effective n main players in the game: long.+transv. polarised effective d long.+transv. polarised effective p ~full hadron ID 1/7/07@ 1:09:56 am

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deep-inelastic scattering Q2Q2 factorisation: 1 GeV 2

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hadron production @ RHIC 0 and jet production xsection vs pT compared to theory

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hadron production no SIDIS xsection measurements @HERMES and CLAS pion multiplicities [deFlorian,Sassot,Stratmann arXiv:0708.0769] compared to theory: DSS: fragmentation functions from combined NLO analysis of single- inclusive hadron production in e+e-, pp and SIDIS

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hadron production no SIDIS xsection measurements @HERMES and CLAS pion multiplicities CLAS 0 compared to HERMES and to DSS:

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SIDIS cross section XYXY beam: target: S L,S T

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SIDIS cross section

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leading-tw distribution functions chiral-odd pdf & FF ‘Amsterdam notation’

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leading-tw distribution functions on the menu today

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@leading twist, integrated over pT: leading-tw distribution functions ‘transversity’

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leading-tw distribution functions @leading twist, no pT integration: ‘transversity’ ‘Kotzinian- Mulders’ ‘pretzelosity’ ‘Boer- Mulders’ ‘Sivers’

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asymmetries and amplitudes + …

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asymmetries and amplitudes taking also into account of the unpolarised cross section Collins moment Sivers moment

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spin-orbit correlations Sivers function: [Matthias Burkardt] a non-zero Sivers fct. requires non-zero orbital angular momentum !

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Sivers amplitudes ep h X [PRL94(2005)] first observation of T-odd Sivers effect in SIDIS u quark dominance suggests sizable u quark orbital motion

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Sivers amplitudes ep h X first observation of T-odd Sivers effect in SIDIS u quark dominance suggests sizable u quark orbital motion [arXiv:0906.3918]

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Sivers amplitudes for [arXiv:0906.3918 ] clear rise with z rise at low P h plateau at high P h T T dominated by u-quarks u-quark Sivers DF < 0

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Sivers amplitudes for [arXiv:0906.3918 ] clear rise with z rise at low P h T plateau at high P h T dominated by u-quarks u-quark Sivers DF < 0 cancellation for : u and d quark Sivers DF of opposite sign

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Sivers amplitudes for [arXiv:0906.3918 ] clear rise with z rise at low P h plateau at high P h T T dominated by u-quarks u-quark Sivers DF < 0 cancellation for : u and d quark Sivers DF of opposite sign all asymmetries on deuterium target ≈ zero! [PLB673(2009)]

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Sivers amplitudes for [arXiv:0906.3918 ] proton data ?

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Sivers amplitudes for [arXiv:0906.3918 ] T T ? ?? proton data

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Sivers distribution for valence quarks transverse SSA of pion cross section difference: Sivers distribution for u- valence is large & <0 or Sivers distr. for d- valence >> u-valence (unlikely)

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Sivers: kaon amplitudes ep K X clear rise with z rise at low P h T plateau at high P h T slightly positive

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Sivers: the “kaon challenge” / K production dominated by scattering off u-quarks

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& non-trival role of sea quarks convolution integral in numerator depends on kT dependence of FF differences in dependences on kinematics integrated over Sivers: the “kaon challenge” / K production dominated by scattering off u-quarks

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role of sea quarks differences biggest in region where strange sea is most different from light sea [PLB666(2008), 446] strange sea pdf

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extracting the Sivers function extracting the Sivers function use parametrisations of unpolarised fragmentation functions see talk by A. Prokudin

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[Anselmino et al., EPJA(2009),89] combined analysis: extracting the Sivers function extracting the Sivers function anti-quark L≠0 favoured

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[Anselmino et al., EPJA(2009),89] combined analysis: extracting the Sivers function extracting the Sivers function Lattice [Haegeler et al.] L u >0 L d <0

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transverse nucleon structure transversity via Collins fragmentation fct. h h qq

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Collins amplitudes positive ≈zero negative ep X distinctive pattern: isospin relation for triplet fulfilled

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Collins amplitudes positive ≈zero negative ep X distinctive pattern: approximation: u-quark dominance Collins FF has favoured ( u ) and unfavoured ( u - ) transitions of similar size and opposite sign

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Collins amplitudes positive ≈zero negative ep X distinctive pattern: approximation: u-quark dominance Collins FF has favoured ( u ) and unfavoured ( u - ) transitions of similar size and opposite sign all asymmetries on deuterium target ≈ zero! proton data [note sign change due to different angle definition ]

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Collins amplitudes positive ≈zero negative ep X distinctive pattern: approximation: u-quark dominance Collins FF has favoured ( u ) and unfavoured ( u - ) transitions of similar size and opposite sign all asymmetries on deuterium target ≈ zero! [PLB673(2009)]

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Collins amplitudes ep h X K + amplitudes consistent with amplitudes as expected from u- quark dominance K of opposite sign from (K is all-sea object)

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extraction of transversity e-e- e+e+ from Collins asymmetries from Collins asymmetries see talk by A. Prokudin

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Collins amplitudes -- extras: 2D binning -- kinematic dependencies often don’t factorise bin in as many independent variables as possible: z @`fixed’ x P h @`fixed’ z z @`fixed’ P h x @`fixed’ z T T

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Collins amplitudes -- extras: 2D binning -- kinematic dependencies often don’t factorise bin in as many independent variables as possible:

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alternative probe for transversity: 2-hadrons

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2-hadron production: interference fragmentation function between pions in s-wave and p-wave only relative momentum of hadron pair relevant integration over transverse momentum of hadron pair simplifies factorisation (collinear!) and Q 2 evolution however cross section becomes very complicated (depends on 9! variables) sensitive to detector acceptance effects

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extraction of amplitudes pythia: integration …facilitate interpretation projects out sp and pp only for full theta acceptance:

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extraction of amplitudes integration …facilitate interpretation projects out sp and pp only for full theta acceptance:

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extraction of amplitudes integration …facilitate interpretation projects out sp and pp only for full theta acceptance: acceptance is momentum dependent: full acceptance

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extraction of amplitudes symmeterization around fit bin data in in addition: &

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amplitudes [JHEP 0806.017]

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h + h - amplitudes [JHEP 0806.017] [note sign change due to different angle definition]

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h + h - amplitudes [JHEP 0806.017] [note sign change due to different angle definition]

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models for 2-hadron asymmetries M (GeV) [Bacchetta, Radici PRD74(2006)]

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models for 2-hadron asymmetries M (GeV) [Bacchetta, Radici PRD74(2006)] [note sign change due to different angle definition]

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azimuthal dependence of the unpolarised cross section spin-orbit effect (Boer-Mulders DF): correlation between quark transverse motion and transverse spin

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unpolarised cross section access to intrinsic quark transverse momentum

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analysis challenge Monte Carlo: generated in 4 measured inside acceptance acceptance and radiative effects generate cos(n ) moments

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analysis challenge Monte Carlo: generated in 4 measured inside acceptance acceptance and radiative effects generate cos(n ) moments 5D unfolding of detector and radiative effects:

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analysis challenge

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cos intrinsic quark transverse momentum very similar result for deuterium

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cos intrinsic quark transverse momentum very similar result for deuterium

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& for p and d targets & for p and d targets

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cos2 spin-orbit correlations very similar result for deuterium

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models for Boer-Mulders DF diquark spectator model same sign for u & d quark BM-DF

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models for Boer-Mulders DF diquark spectator model compares well to HERMES data w/o inclusion of tw-4 Cahn effect

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models for Boer-Mulders DF scaled Sivers fct. inclusion of tw-4 Cahn effect [V. Barone, A. Prokudin, Bo-Quiang Ma, PRD78 (2008)]

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models for Boer-Mulders DF

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work in progress for tw-4 Cahn effect [V. Barone, S. Mellis, A. Prokudin]

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models for Boer-Mulders DF

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transversely polarised quarks in longitudinally polarised nucleons Kotzinian-Mulders fct.

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transversely polarised quarks in longitudinal polarised nucleons

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next @Jlab

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next @HERMES pT weighted Sivers & Collins moments resolve convolution integral ! extraction of all 8 leading tw modulations ++

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next @HERMES pT weighted Sivers & Collins moments resolve convolution integral ! extraction of all 8 leading tw modulations ++ next @COMPASS request to CERN: 2010 full year run (140 days) with transversely polarised protons [… investigation of upgrade for higher muon beam intensity and spectrometer upgrades]

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theo ry [by Naomi Makins] looking forward to new projects: Jlab12, EIC, PAX@FAIR see talks by H. Avakian & R. Ent on friday

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BACKUP SLIDES [courtesy of A. Bacchetta]

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Sivers: Q 2 dependence factor 2 factor 3

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Experimental status: EMC E665 ZEUS c) Negative results in all the existing measurements No distinction between hadron type or charge

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Experimental status: EMC ZEUS collaboration ZEUS Drell-Yan Positive results in all the existing measurements No distinction between hadron type or charge (in SIDIS experiments) Indication of small Boer-Mulders function for the sea quark (from Drell-Yan experiments)

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