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

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 1:09:56 am

deep-inelastic scattering Q2Q2 factorisation: 1 GeV 2

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

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

hadron production no SIDIS xsection and CLAS  pion multiplicities CLAS  0 compared to HERMES and to DSS:

SIDIS cross section XYXY beam: target:   S L,S T

SIDIS cross section

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

leading-tw distribution functions on the menu today

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

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

asymmetries and amplitudes + …

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

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

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

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

Sivers amplitudes for  [arXiv: ] 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

Sivers amplitudes for  [arXiv: ] 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

Sivers amplitudes for  [arXiv: ] 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)]

Sivers amplitudes for  [arXiv: ] proton data ?

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

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)

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

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

&  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

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

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

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

[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

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

Collins amplitudes     positive   ≈zero   negative ep    X distinctive pattern:  isospin relation for  triplet fulfilled

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

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 ]

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)]

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)

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

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

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

alternative probe for transversity: 2-hadrons

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

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

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

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

extraction of     amplitudes symmeterization around  fit  bin data in  in addition: &

    amplitudes [JHEP ]

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

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

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

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

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

unpolarised cross section access to intrinsic quark transverse momentum

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

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:

analysis challenge

 cos  intrinsic quark transverse momentum very similar result for deuterium

 cos  intrinsic quark transverse momentum very similar result for deuterium

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

 cos2  spin-orbit correlations very similar result for deuterium

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

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

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

models for Boer-Mulders DF

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

models for Boer-Mulders DF

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

transversely polarised quarks in longitudinal polarised nucleons

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

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

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

BACKUP SLIDES [courtesy of A. Bacchetta]

Sivers: Q 2 dependence factor 2 factor 3

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

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)