V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Victor I. Mokeev Jefferson Lab Workshop scope and N* parameters available/expected from the CLAS/CLAS12 detector data. Victor I. Mokeev Jefferson Lab

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA 2 Nucleon Resonance Studies with CLAS12 R. Arndt 4, H. Avakian 6, I. Aznauryan 11, A. Biselli 3, W.J. Briscoe 4, V. Burkert 6, V.V. Chesnokov 7, P.L. Cole 5, D.S. Dale 5, C. Djalali 10, L. Elouadrhiri 6, G.V. Fedotov 7, T.A. Forest 5, E.N. Golovach 7, R.W. Gothe* 10, Y. Ilieva 10, B.S. Ishkhanov 7, E.L. Isupov 7, K. Joo 9, T.-S.H. Lee 1,2, V. Mokeev* 6, M. Paris 4, K. Park 10, N.V. Shvedunov 7, G. Stancari 5, M. Stancari 5, S. Stepanyan 6, P. Stoler 8, I. Strakovsky 4, S. Strauch 10, D. Tedeschi 10, M. Ungaro 9, R. Workman 4, and the CLAS Collaboration Approved by PAC for 40 days beam time for the first five years of running Argonne National Laboratory (IL,USA) 1, Excited Baryon Analysis Center (VA,USA) 2, Fairfield University (CT, USA) 3, George Washington University (DC, USA) 4, Idaho State University (ID, USA) 5, Jefferson Lab (VA, USA) 6, Moscow State University (Russia) 7, Rensselaer Polytechnic Institute (NY, USA) 8, University of Connecticut (CT, USA) 9, University of South Carolina (SC, USA) 10, and Yerevan Physics Institute (Armenia) 11 Spokesperson Contact Person*

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA 3 Anticipated N* Electrocouplings from a Combined Analysis of N  & N  Open circles represent projections and all other markers the available results with the 6-GeV electron beam Examples of published and projected results obtained within 60d for three prominent excited proton states from analyses of N  and N  electroproduction channels. Similar results are expected for many other resonances at higher masses, e.g. S 11 (1650), F 15 (1685), D 33 (1700), P 13 (1720), … Our experiment will – for the foreseeable future – be the only experiment that can provide data on  v NN* electrocouplings for almost all well established excited proton states at the highest photon virtualities ever achieved in N* studies up to Q 2 of 12 GeV 2 S 11 (1535)D 13 (1520)P 11 (1440) CLAS Hall C

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA 4  v NN* Electrocouplings at Q 2 >5.0 GeV 2 as a probe of the Resonance Quark Structure Meson-Baryon Dressing absolute values of meson-baryon dressing amplitudes ( EBAC) quark core contributions (constituent quark models) D 13 (1520) Resonance structures can be described in terms of an internal quark core and a surrounding meson-baryon cloud whose relative contribution decreases with increasing Q 2. Data on  v NN* electrocouplings from this experiment (Q 2 > 5 GeV 2 ) will afford for the first time direct access to the non-perturbative strong interaction among dressed quarks, their emergence from QCD, and the subsequent N* formation. P 11 (1440) CLAS: N  and N  N  combined (Phys. Rev. C80, , 2009)

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA  v NN* Electrocouplings at Q 2 >5.0 GeV 2 as a probe of the Resonance Quark Structure Topic for discussion: Prospects to establish the area of Q 2 with minor meson-baryon dressing for N* states of various quantum numbers within the framework of the EBAC-DCC approach

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA 6 Theory Support Group I.Aznauryan 9, V.M. Braun 8, S.Capstick 3, I.Cloët 10, R. Edwards 6, M.M. Giannini 5,7, B. Julia-Diaz 2, H. Kamano 2, T.-S.H. Lee 1,2, A. Lenz 8, H.W. Lin 6, A. Matsuyama 2, C.D. Roberts 1, E. Santopinto 5,7, T. Sato 2, G. Schierholz 8, N. Suzuki 2, Q. Zhao 4, and B.-S. Zou 4 Argonne National Laboratory (IL,USA) 1, Excited Baryon Analysis Center (VA,USA) 2, Florida State University(FL,USA) 3 Institute of High Energy Physics (China) 4, Istituto Nazionale di Fisica Nucleare (Italy) 5, Jefferson Lab (VA, USA) 6, University of Genova (Italy) 7,University of Regensburg (Germany) 8, Yerevan Physics Institute (Armenia) 9 and University of Washington (WA, USA) 10 : “Theory Suport for the Excited Baryon Program at the JLAB 12 GeV Upgrade”, arXiv: [nucl-th].

V.I.Mokeev User Group Meeting June V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Major directions in theoretical interpretation of  v NN* electrocouplings Interpretation  of  v NN* electrocouplings in LQCD.  QCD-based description of  v NN* electrocouplings within the framework of DSE. Combined LQCD and Light Cone Sum Rule (LCSR) approach. Constituent Quark Models.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA N* electrocouplings from LQCD F 1,2 form factors for P-P 11 (1440) transition (exploratory calculations) Current calculations with m  ~0.5 GeV, stable P 11 (1440) and limited operator basis H.W.Lin et al, Phys.Rev. D78, (2008) Topics for discussion: Which N* parameters can be evaluated in LQCD for unstable excited states? Prospects to determine  v NN* electrocouplings from the QCD Lagrangian at Q 2 >5.0 GeV 2, approaching physical pion mass and appropriate box size.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA LQCD & Light Cone Sum Rule (LCSR) Approach S 11 (1535) CLAS Hall C V.Braun et al., Phys. Rev. Lett.,103, (2009). m  =380 MeV m  =280 MeV Topics for discussions: The prospects for evaluation of S 11 (1535) electrocouplings at Q 2 >2.0 GeV 2 with pion masses closer to physical limit. Can these evaluations be extended for others parity partners? Prospect to relate results on gvNN* electrocouplings and quark distribution amplitudes in N*’s.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Dyson-Schwinger Equation (DSE) Approach strong confinement quark anom. chromo- magn. moment quark anom. electro magn. moment L.Chang et al, PRL 106, (2011) Topics for discussions: The prospects to observe manifestation of running dynamical quark masses and structure in Q 2 evolution of N* electrocouplings Prospects to compare LQCD and DSE evaluation for quark/gluon propagators and quark-gluon vertices in infrared

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Only available tool to evaluate electrocouplings of most N* states Electrocouplings of most excited proton states are already available at Q 2 <4.0 GeV 2 from hQCM by M. Giannini/E. Santopinto Constituent Quark Models Topics for discussions: Light front and other approaches for relativistic treatment High Fock components at high Q 2 Prospects of AdS/CFT in describing N* electrocouplings at high Q 2 How constituent quark models can be related to QCD in the domain 2.0<Q 2 <10 GeV 2, where quark mass running becomes most evident ??

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA N* parameters from analyses of exclusive electroproduction channels γvγv N N’N’ N*,△ A 3/2, A 1/2, S 1/2 G M, G E, G C  N N’N’ + * Resonant amplitudes Non-resonant amplitudes A 1/2, A 3/2, and S 1/2 electrocouplings are proportional to the helicity amplitudes for transition between the initial photon-proton state of the initial particle helicities, and the final state with unstable N*,  * resonances. Electrocouplings are well defined, directly related to N* structure and are part of observable quantities, e.g. cross sections.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA N* parameters from analyses of exclusive electroproduction channels Separation of resonant/non-resonant contributions represents most challenging part, and can be achieved within the framework of reaction models. N* ‘s can couple to various exclusive channels with entirely different non-resonant amplitudes, while their electrocouplings should remain the same. Consistent results from the analyses of major meson electroproduction channels show that model uncertainties in extracted N* electrocouplings are under control. Will similar strategy be feasible for LQCD evaluation of  v NN* electrocouplings?

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA  v NN* electrocouplings from the CLAS data on N  /N  electroproduction N  CLAS preliminary. N  CLAS Good agreement between the electrocouplings obtained from the N  and N  channels. N* electrocouplings are measurable and model independent quantities. I. Aznauryan,V. Burkert, et al., PRC 80, (2009). A 1/2 S 1/2 A 3/2 F 15 (1685) A 3/2 P 11 (1440) D 13 (1520) N  world V. Burkert, et al., PRC 67, (2003). N  Q 2 =0, PDG. N  Q 2 =0, CLAS M. Dugger, et al., PRC 79, (2009).

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA The web-page with the data on  v NN* electrocouplings Numerical results on  v NN* electrocouplings determined from analyses of meson electroproduction data may be found in: Relations between  v NN* electrocouplings and N* electromagnetic decay widths are given under the link “Definition” The web-page incorporates all CLAS results, and only available for us part of the  v NN* electrocouplings obtained worldwide The CLAS data on N  electromagnetic form factors are published in I.G. Aznauryan, et al., PRC 80, (2009) All comments can be sent to V.Mokeev Submission of the results on  v NN* electrocouplings is

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Reaction models for extraction of  v NN* electrocouplings at Q 2 >5.0 GeV 2 Separation between resonant/non-resonant contributions in N* analyses carried out so far was achieved employing reaction models with meson- baryon (MB) degrees of freedom. At Q 2 >5.0 GeV 2 MB degrees of freedom are mostly replaced by relevant quark degrees of freedom. Such a behavior is encoded in MB vertices cut-off parameters  2 ~1.0 GeV 2 ), and supported by preliminary analyses of the CLAS  +  - p data at Q 2 >2.0 GeV 2.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Reaction models for extraction of  v NN* electrocouplings at Q 2 >5.0 GeV 2 Reaction models are needed for description of N  and N  electroproduction at W 5.0 GeV 2 that employ relevant quark degrees of freedom, and which are capable of describing non-resonant contributions to  + n  0 p,  and  p reaction channels, at least. Combined approaches that incorporate superposition of explicit MB/quark mechanisms and phenomenological parametrization of remaining contributions represent a reasonable initial option.

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Preliminary analysis of the CLAS π + π - p electroproduction data at Q 2 >2.0 GeV 2 Data fit requires to increase effective coupling with  Regge trajectory by a factor ~1.8 Indication of the transition to other degrees of freedom Q 2 (GeV 2 ) Resonance structures become more prominent with increasing Q 2. D 33, P 13, F 15 3/2 + (1720) D 13 Extension of JM model toward high Q 2 Very preliminary data and analysis

V.I.Mokeev NSTAR at high Q2 Workshop, May 16, 2011, Jefferson Lab, Newport News, VA Workshop Expectations  Tools for based on QCD theoretical interpretations of  v NN* electrocouplings  further development  Reaction models for N  and N  electroproduction at W 5.0 GeV 2  establishment of the framework, commitments…..  The White Paper