Factorization and Transverse Momentum in SIDIS at JLab

Slides:



Advertisements
Similar presentations
Target Fragmentation studies at JLab M.Osipenko in collaboration with L. Trentadue and F. Ceccopieri, May 20,SIR2005, JLab, Newport News, VA CLAS Collaboration.
Advertisements

QCD N06 - Monte Porzio Catone - 15/06/ SIDIS Cross Sections and Spin Asymmetries Predictions for Ongoing and Future Experiments M.Elena Boglione.
Constraining the polarized gluon PDF in polarized pp collisions at RHIC Frank Ellinghaus University of Colorado (for the PHENIX and STAR Collaborations)
10/03/'06 SPIN2006, T. Horaguchi 1 Measurement of the direct photon production in polarized proton-proton collisions at  s= 200GeV with PHENIX CNS, University.
Working Group on e-p Physics A. Bruell, E. Sichtermann, W. Vogelsang, C. Weiss Antje Bruell, JLab EIC meeting, Hampton, May Goals of this parallel.
Working Group on e-p Physics A. Bruell, E. Sichtermann, W. Vogelsang, C. Weiss Antje Bruell, JLab EIC meeting, Stony Brook, Dec Physics Topics Working.
THE DEEP INELASTIC SCATTERING ON THE POLARIZED NUCLEONS AT EIC E.S.Timoshin, S.I.Timoshin.
Measurements of F 2 and R=σ L /σ T on Deuteron and Nuclei in the Nucleon Resonance Region Ya Li January 31, 2009 Jlab E02-109/E (Jan05)
Spin Azimuthal Asymmetries in Semi-Inclusive DIS at JLAB  Nucleon spin & transverse momentum of partons  Transverse-momentum dependent distributions.
Experimental Approach to Nuclear Quark Distributions (Rolf Ent – EIC /15/04) One of two tag-team presentations to show why an EIC is optimal to access.
P Spring 2003 L9Richard Kass Inelastic ep Scattering and Quarks Elastic vs Inelastic electron-proton scattering: In the previous lecture we saw that.
Spin-Flavor Decomposition J. P. Chen, Jefferson Lab PVSA Workshop, April 26-27, 2007, Brookhaven National Lab  Polarized Inclusive DIS,  u/u and  d/d.
Spin and azimuthal asymmetries in SIDIS at JLAB  Physics Motivation  Jlab kinematics and factorization  Double spin asymmetries  Single Spin Asymmetries.
New results on SIDIS SSA from JLab  Physics Motivation  Double spin asymmetries  Single Spin Asymmetries  Future measurements  Summary H. Avakian.
P. Bosted, DNP Spin and azimuthal asymmetries in SIDIS at JLAB  Physics Motivation  Jlab kinematics and factorization  Single Spin Asymmetries.
Particle Physics Chris Parkes Experimental QCD Kinematics Deep Inelastic Scattering Structure Functions Observation of Partons Scaling Violations Jets.
Duality: Recent and Future Results Ioana Niculescu James Madison University Hall C “Summer” Workshop.
16/04/2004 DIS2004 WGD1 Jet cross sections in D * photoproduction at ZEUS Takanori Kohno (University of Oxford) on behalf of the ZEUS Collaboration XII.
Future Physics at JLab Andrew Puckett LANL medium energy physics internal review 12/14/
The Role of Higher Twists in Determining Polarized Parton Densities E. Leader (London), A. Sidorov (Dubna), D. Stamenov (Sofia) 12th International Workshop.
Single-Spin Asymmetries at CLAS  Transverse momentum of quarks and spin-azimuthal asymmetries  Target single-spin asymmetries  Beam single-spin asymmetries.
Peter Bosted (Jefferson Lab and William and Mary) Spin structure of the nucleon: update from CLAS at JLab Los Alamos, September 2011.
Measurements with Polarized Hadrons T.-A. Shibata Tokyo Institute of Technology Aug 15, 2003 Lepton-Photon 2003.
1 Harut Avakian Studies on transverse spin effects at Jlab QCD Structure of the Nucleon June 12-16, 2006, Rome Physics motivation k T -effects from unpolarized.
Thomas Jefferson National Accelerator Facility PAC-25, January 17, 2004, 1 Baldin Sum Rule Hall C: E Q 2 -evolution of GDH integral Hall A: E94-010,
DIS Conference, Madison WI, 28 th April 2005Jeff Standage, York University Theoretical Motivations DIS Cross Sections and pQCD The Breit Frame Physics.
Harut Avakian (Jlab) DVCS results with unpolarized and polarized target Introduction Event selection MC simulations and radiative corrections DVCS with.
Measurement of Flavor Separated Quark Polarizations at HERMES Polina Kravchenko (DESY) for the collaboration  Motivation of this work  HERMES experiment.
The Spin Physics Program at Jefferson Lab Sebastian Kuhn Old Dominion University e e PtPt PePe.
Factorization and Transverse Momentum in SIDIS at JLab P. Bosted, H. Avakian (JLab)  Semi-inclusive processes  Factorization as a test of quark-hadron.
Costas Foudas, Imperial College, Jet Production at High Transverse Energies at HERA Underline: Costas Foudas Imperial College
F Don Lincoln f La Thuile 2002 Don Lincoln Fermilab Tevatron Run I QCD Results Don Lincoln f.
Experimental Studies of Spin Duality P. Bosted (JLab) Jlab Users Meeting, June 2005  Bloom-Gilman duality in inclusive g 1  Factorization in polarized.
1 CLAS-eg1 pol.-proton analysis H.Avakian (JLab) semi-SANE Collaboration Meeting April 21, 2005.
1 Proton Structure Functions and HERA QCD Fit HERA+Experiments F 2 Charged Current+xF 3 HERA QCD Fit for the H1 and ZEUS Collaborations Andrew Mehta (Liverpool.
Timelike Compton Scattering at JLab
Flavor decomposition at LO
Generalized Parton Distributions and Deep Virtual Compton Scattering
Probing strangeness in hard processes Laboratori Nazionali di Frascati
Explore the new QCD frontier: strong color fields in nuclei
(Anti)Lambda polarization in SIDIS
Spin and azimuthal asymmetries in SIDIS at JLAB
Measurements of quark transversity and orbital motion in hard scattering Yoshiyuki Miyachi Tokyo Institute of Technology.
Measurement of GPDs at JLab and in Future at Colliders
Charged Particle Multiplicity in DIS
Observation of Diffractively Produced W- and Z-Bosons
Charged Particle Multiplicity in DIS
Open Heavy Flavour Production at HERA
Determination of g/g from Hermes High-pT hadrons
Semi-inclusive DIS at 12 GeV
Larisa Nogach Institute of High Energy Physics, Protvino
Duality in Semi-Inclusive DIS
Selected Physics Topics at the Electron-Ion-Collider
Masanori HIRAI 2006, Nov 9, Tokyo-u
Investigation on QCD group
Searching for intrinsic motion effects in SIDIS
Duality in Pion Electroproduction (E00-108) …
Transverse Momentum Dependence of Charged Pion Production
Radiative corrections FOR PYTHIA
Peter Bosted (Jefferson Lab)
Target Fragmentation and Fracture Functions an introduction
in the Rein-Sehgal Model
Observation of Diffractively Produced W- and Z-Bosons
Scaling Study of the L-T Separated p(e,e’π+)n Cross Section at Large Q2 Tanja Horn Jefferson Lab APS/DNP meeting 2007 DNP07 October 2007.
Heavy Flavour Content of the Proton
Update of RG-A Hadron Structure Analyses
Semi-Inclusive DIS measurements at Jefferson Lab
New results on SIDIS SSA from JLab
25.5 days at 11.0 GeV & 6.5 days at 8.8 GeV = 32 days total
The Helicity Structure of the Nucleon from Lepton Nucleon Scattering
Presentation transcript:

Factorization and Transverse Momentum in SIDIS at JLab P. Bosted (JLab) CIPANP06, Puerto Rico, May 2006 Semi-inclusive processes Factorization as a test of quark-hadron duality Factorization tests in unpolarized SIDIS Facorization tests in polarized SIDIS Tranverse momentum in fragmentation Note mes

Semi-inclusive DIS orbital motion of quarks (pt, f dependence) pion Main focus of SIDIS studies: MX orbital motion of quarks (pt, f dependence) parton distributions (separate valence, sea) X.Ji Where region I/II boundary? Can useful information come from Region II?

SIDIS kinematic plane and relevant variables pion MX Pt is transverse momentum relative to virtual photon W2=M2+Q2(1/x-1) is invariant mass of total hadronic final state

Factorzation in SIDIS Basic idea: hit a single quark in nucleon which then hadronizes into a jet with negligible interaction with remenant quarks. s(x,z,pt) =? PDF(x,kt) x Frag.Fun.(z,pt) Example, SIDIS p+ from u quark in proton sp+(x,z,pt) =? u(x,kt) x D+(z,pt) High z used to distinguish current fragmentation from target fragmentation.

Missing mass of pions in ep->e’pX with 6 GeV electrons D++ p- D0 Duality question: will factorization work if Mx<2 GeV, even though D(1232) reonance visible? For p-, guess need Mx>1.4 GeV.

EXPERIMENT E00-108 at JLAB Halll C Unpolarized electrons E=6 GeV Scattered electrons E’=1.6 GeV, 25 to 40 deg. Average Q2 2.5 GeV2. W about 2.5 GeV, but Mx<2 GeV. Detected positive and negative pions near 12 degrees Proton and deuteron targets Made scans in x, z. pt<0.2 GeV

Z-Dependence of cross sections Good agreement with prediction using CTEQ5M PDFs and Binnewies fragmentation functions, except for z>0.7, or Mx>1.4 GeV. D or D+,D- X=0.3, Q2=2.5 GeV2, W=2.5 GeV

In more detail, form super-ratios Simple LO picture in valence region: sp(p+) = 4u(x,pt)D+(z,pt) + d(x,pt)D-(z,pt) sp(p-) = 4u(x,pt)D-(z,pt) + d(x,pt)D+(z,pt) sd(p+) = [u(x,pt)+d(x,pt)] [4D+(z,pt) + D-(z,pt)] sd(p-) = [u(x,pt)+d(x,pt)] [4D-(z,pt) + D+(z,pt)] Rpd+= [sp(p+) + sp(p-)] / [sd(p+) + sd(p-)] = [4u(x,pt) + d(x,pt)] / 5[u(x,pt)+d(x,pt)] = sp(x)/sd(x) for any z, x, pt (if d and u have same pt depdendence)!

In more detail, form super-ratios Simple LO picture in valence region: sp(p+) = 4u(x,pt)D+(z,pt) + d(x,pt)D-(z,pt) sp(p-) = 4u(x,pt)D-(z,pt) + d(x,pt)D+(z,pt) sd(p+) = [u(x,pt)+d(x,pt)] [4D+(z,pt) + D-(z,pt)] sd(p-) = [u(x,pt)+d(x,pt)] [4D-(z,pt) + D+(z,pt)] Rpd-= [sp(p+) - sp(p-)] / [sd(p+) - sd(p-)] = [4uv(x,pt) - dv(x,pt)] / 3[uv(x,pt)+dv(x,pt)] for any z, x!

Rpd+ Rpd- Both ratios agree PDF models for z<0.7 (Nx>1.4 GeV)

Rpd+ Rpd- Both ratios independent of pt (to 0.3 GeV) for z=0.55

Rpd+ Rpd- Both ratios agree PDF models 0.2<x<0.5 for z=0.55 (possible complications x>0.5)

Another test: D-/D+ from Deuteron p+ to p- ratio sd(p+) = [u+d] [4D++D-] sd(p-) = [u+d] [4D-+D+] Results agree HERMES (higher W, Mx>2 GeV) up to z=0.7 (Mx>1.4 at pt=0), after rho correction

Another test: D-/D+ from Deuteron p+ to p- ratio Results agree HERMES and EMC for z=0.55 and x>0.35. Maybe some x depdendence x<0.35 (sea quark correction?)

Now to polarized SIDIS at JLAB using CLAS Scattering of 5.7 GeV polarized electrons off polarized NH3, ND3 ~8M p+ in SIDIS kinematics x x

Determination of g1/F1 (approximately A1) Target polarization about 0.7 (0.3) for NH3 (ND3) Longitudinal beam polarization PB about 0.7 Dilution factor f varies from 0.1 to 0.3: used Lund model for n/p ratio (agrees with Hall C data) and preliminary Hall B data for A-dependence Depolarization factor DLL(y) evaluated assuming R=sL/sT same as for inclusive. Assumed Aperp=0 (not measured) “p+” and “p-” include some K+, K- for P>1.5 GeV p0 events cleanly identified with two photons

x-depenence of SIDIS proton g1/F1 W>2 GeV, Q2>1.1 GeV2, 0.4<z<0.7 Good agreement with HERMES p+ data at higher W. x-dependence follows PEPSI (Lund) Monte Carlo using GRSV polarized PDFs (LO) Magnitude also in good agreement with simulation

Proton (g1/F1)+- and (g1/F1)0 should be independent of Polarized SIDIS: factorization tests Simple picture in valence region: sp(p+) = 4u(x)D+(z) + d(x)D-(z) sp(p-) = 4u(x)D-(z) + d(x)D+(z) dsp(p+) = 4du(x)D+(z) + dd(x)D-(z) dsp(p-) = 4du(x)D-(z) + dd(x)D+(z) (g1/F1)+-=[dsp(p+)+dsp(p-)]/[sp(p+)+sp(p-)] = [4du(x) + dd(x)] / [4u(x) + d(x)] = (g1/F1)inclusive Similarly for p0 (g1/F1)0= (g1/F1)inclusive Proton (g1/F1)+- and (g1/F1)0 should be independent of z and pt, and equal to inclusive (g1/F1)

Polarized SIDIS factorization test Significant ? GRVS g1/F1 for inclusive, for the sum of p+ ,p- , and for p0 are fairly consistent with each other in the range 0.4<z<0.7, as expected in LO if factorization works. Cuts used: Mx>1.4 GeV, Q2>1.1 GeV2, W>2 GeV

z-depenence of SIDIS proton g1/F1 No significant z-dependence seen for p0 and p++ p- for 0.3<z<0.7, as expected if factorization holds Good agreement with PEPSI predictions including dropoff at high z for p-, due to increasing importance of dd(x), in turn due to increase of D+/D- with increasing z CLAS 5.7 GeV PRELIMINARY

pt-depenence of SIDIS proton g1/F1 CLAS 5.7 GeV PRELIMINARY pt No pt dependence for p0 (green), and average of p+ (red) and p- (blue) as expected if factorization works

pt-depenence of SIDIS proton g1/F1 BUT, A1(p+ ) decreases with pt at fixed x,Q2,z while A1( p- ) increases. Hard to explain in terms of different pt distributions for quarks, or influence of exclusive processes like diffractive rho production. Simplest explanation is that D-/D+ increases with pt (I.e. unfavored fragmentation has a wider transverse momentum dependence) First hint? This effect magnified in g1 compared to F2 due to dd negative while du positive dsp(p+) = 4du(x,pt)D+(z,pt) + dd(x,pt)D-(z,pt) dsp(p-) = 4du(x,pt)D-(z,pt) + dd(x,pt)D+(z,pt)

In region where factorization tests hold, can use data to constrain polarized PDFs in NLO analysis(separate out polarized up, down valence and sea quark parton distributions). CLAS 5.7 GeV PRELIMINARY

In region where factorization tests hold, analyze f depdendence of ALL, ALU, and AUL to learn about orbital motion of quarks, polarized fragmentation, and higher twist contributions. CLAS 5.7 GeV PRELIMINARY

Future Full NLO, higher twist anlayses 20x more p+, p -, 40x more p0 for g1/F1 at 6 GeV on proton (using CLAS) 3x more p+ and p- g1/F1 data on deuteron (Hall C) Jlab upgrade to 11 GeV electrons combined with major upgrade to CLAS will allow huge increase in kinematic coverage and statstical accuracy in SIDIS!

Summary Factorization in SIDIS pion production seems to work for 0.3<z<0.7, W>2 GeV, Mx>1.4 GeV, 0.2<x<0.5, Q2>1 GeV2. Opens opportunity for studies of PDF’s, and orbital motion of quarks Jlab upgrade will allow definitive measurements for x>0.1 Last but not least, is pt dependence of fragmentation function different for favored and unfavored?

To obtain fraction of events from polarized protons (deuterons) in NH3 (ND3), used recent data for deuteron to carbon ratio in SIDIS from E02-104 (Will Brooks). Few representative points shown. MUCH MORE DATA coming soon over wide kinematic range. Studies quark propogation in cold QCD matter. CLAS 5.7 GeV PRELIMINARY