1. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Studies of N* Structure from the CLAS Meson Electroproduction Data N,N* quark core MENU 2013 Conference M. Ripani, INFN Genova

2. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Studies of the N*-Structure in Exclusive Meson Electroproduction Our experimental program seeks to determine  v NN* electrocouplings at photon virtualities up to 5.0 GeV 2 for most of the excited proton states through analyzing major meson electro- production channels independently and in global multi- channel analyses. This information is needed to study the evolution of relevant degrees of freedom in N* structure with distance and to access the non-perturbative strong interaction which generates N* states as bound systems of quarks and gluons (see I. G. Aznauryan et al., Int. J. Mod. Phys. E22, 133015 (2013)). The non-perturbative strong interaction represents the most important part of the Standard Model that we have yet to explore. It is the only fundamental sector where relevant degrees of freedom accessible in the measurements can be very different with respect to those entered in the basic QCD Lagrangian.

3. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Extraction of  v NN* electrocouplings from the data on exclusive meson electroproduction off protons γvγv N N’N’ N*,△ A 1/2 (Q 2 ), A 3/2 (Q 2 ), S 1/2 (Q 2 ) or G 1 (Q 2 ), G 2 (Q 2 ), G 3 (Q 2 ) or G M (Q 2 ), G E( Q 2 ), G C (Q 2 )  N N’N’ + * Separation of resonant/non-resonant contributions within the framework of reaction models; Breit Wigner ansatz for parameterization of resonant amplitudes; fit of resonance electroexcitation and hadronic parameters to the data. Consistent results on  v NN* electrocouplings from different meson electroproduction channels and different analysis approaches demonstrate reliable extraction of N* parameters. Resonant amplitudes Non-resonant amplitudes N*’s photo-/electrocouplings  v NN* are defined at W=M N* through the N* electromagnetic decay width  : See details in: I.G.Aznauryan and V.D.Burkert, Progr. Part. Nucl. Phys. 67, 1 (2012). e e’

4. V.I.Mokeev User Group Meeting June 18 2008 CEBAF Large Acceptance Spectrometer Liquid D 2 (H 2 )target +  start counter; e minitorus Drift chambers argon/CO 2 gas, 35,000 cells Electromagnetic calorimeters Lead/scintillator, 1296 PMTs Torus magnet 6 superconducting coils Gas Cherenkov counters e/  separation, 216 PMTs Time-of-flight counters plastic scintillators, 684 PMTs Large angle calorimeters Lead/scintillator, 512 PMTs The unique combination of the CEBAF continuous electron beam and the CLAS detector makes Hall-B@JLAB the only facility operational worldwide, that is capable of measuring unpolarized cross sections and polarization asymmetries of most exclusive meson electroproduction channels with substantial contributions at W<3.0 GeV and Q 2 <5.0 GeV 2. V.I.Mokeev, NSTAR 2013 Workshop Peniscola, Spain, May 27-30, 2013

5. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Summary of the CLAS Data on Exclusive Meson Electroproduction off Protons in N* Excitation Region Hadronic final state Covered W-range, GeV Covered Q 2 - range, GeV 2 C Measured observables +n+n 1.1-1.40 1.1-1.55 1.1-1.7 0.15-0.40 0.3-0.6 1.7-4.2 d  /d  d  /d  A b 0p0p 1.1-1.40 1.1-1.7 0.15-0.40 0.4-0.7 0.75-6.0 d  /d  d  /d  A b,A t,A bt d  /d  pp 1.5-2.0 0.2-4.0 d  /d  K+K+ 1.65-2.35 0.65-2.55 1.4-2.6 d  /d  P’ K+K+ 1.7-2.1 1.8-2.5 1.7-2.6 0.5-2.55 1.5-3.50 1.8-3.50 d  /d  P’ d  /d  +-p+-p 1.3-1.6 1.4-2.1 0.2-0.6 0.5-1.5 Nine 1-fold differential cross sections d  /d  CM angular distributions A b,A t,A bt -longitudinal beam, target, and beam-target asym- metries P’ –recoil polarization of strange baryon The data are available in the CLAS Physics Data Base: http://depni.sinp.msu.ru/cgi-bin/jlab/db.cgi Almost full coverage of the final hadron phase space in  N,  +  - p,  p, and KY electroproduction

6. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 CLAS data on yields of meson electroproduction at Q 2 <4 GeV 2 N* Electroexcitation in Exclusive Meson Electroproduction off Protons StateBran. Fract. to N . Bran. Fract. to N  Bran.Fract. Nππ Δ(1232)P 33 0.995 N(1440)P 11 0.55-0.750.3-0.4 N(1520)D 13 0.55-0.65 0.4-0.5 N(1535)S 11 0.48±0.030.46±0.02  (1620)S 31 0.20-0.300.70-0.80 N(1650)S 11 0.60-0.950.03-0.110.1-0.2 N(1685)F 15 0.65-0.700.30-0.40 Δ(1700)D 33 0.1-0.20.8-0.9 N(1720)P 13 0.1-0.2> 0.7 Hadronic decays of prominent N*s at W<1.8 GeV.

7. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Analyses of different meson electroproduction channels independently:   + n and  0 p channels: Unitary Isobar Model (UIM) and Fixed-t Dispersion Relations (DR) I.G.Aznauryan, Phys. Rev. C67, 015209 (2003). I.G.Aznauryan et al., CLAS Coll., Phys Rev. C80, 055203 (2009).   p channel: Extension of UIM and DR I.G.Aznauryan, Phys. Rev. C68, 065204 (2003). Data fit at W<1.6 GeV, assuming S 11 (1535) dominance H.Denizli et al., CLAS Coll., Phys.Rev. C76, 015204 (2007).   +  - p channel: Data driven JLAB-MSU meson-baryon model (JM) V.I.Mokeev, V.D.Burkert et al., Phys. Rev. C80, 045212 (2009). V.I.Mokeev et al., CLAS Coll., Phys. Rev. C86, 035203 (2012).  Global coupled-channel analyses of the CLAS/world data of  N,  v N →  N,  N,  N, K , K  exclusive channels: N. Suzuki, T. Sato, T.-S.H. Lee, Phys.Rev. C82 (2010) 045206 H. Kamano, T.-S. H. Lee, AIP Conf.Proc. 1432 (2012) 74-79 Approaches for Extraction of  v NN* Electrocouplings from the CLAS Exclusive Meson Electroproduction Data

8. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Fits to  V p→   n Differential Cross Sections and Structure Functions DR UIM DR w/o P11 DR UIM Q 2 =2.44 GeV 2 Q 2 =2.05 GeV 2 Legendre moments D l (l=0,1,2) from various structure functions d  /d  

9. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 The CLAS Data on     p Differential Cross Sections and their Fit within the Framework of Meson-Baryon Reaction Model JM full JM calc.  -  ++ +0+0 2  direct pp  + D 0 13 (1520)  + F 0 15 (1680) G.V.Fedotov et al, PRC 79 (2009), 015204 1.30<W<1.56 GeV; 0.2<Q 2 <0.6 GeV 2 M.Ripani et al, PRL 91 (2003), 022002 1.40<W<2.30 GeV; 0.5<Q 2 <1.5 GeV 2

10. V.I.Mokeev User Group Meeting June 18 2008 10 JM Model Analysis of the  +  - p Electroproduction Major objectives: extraction of  v NN* electrocouplings and ,  p decay widths. V.I.Mokeev, V.D. Burkert, et al., (CLAS Collaboration) Phys. Rev. C86, 035203 (2012). V.I.Mokeev, V.D. Burkert, et al., Phys. Rev. C80, 045212 (2009).   p p’    (1232)P 33, N 0 (1520)D 13,   (1600)P 33, N 0 (1680)F 15   p’     p p p p’,p’, … p’        …      … = ++ six meson-baryon channels and direct  +  - p production. N* contribute to  and  p channels only. unitarized Breit-Wigner ansatz for resonant amplitudes.  V.I.Mokeev, NSTAR 2013 Workshop Peniscola, Spain, May 27-30, 2013

11. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Developed based on approach: I.J.R.Aitchison, Nuclear Physics, A189 (1972), 417. Off-diagonal transitions incorporated into the full resonant amplitudes of the JM model: S 11 (1535) ↔ S 11 (1650) D 13 (1520) ↔ D 13 (1700) 3/2 + (1720) ↔ P 13 (1700) Inverse of the JM unitarized N* propagator: N*  diagonal N*  N*  off-diagonal Unitarized Breit-Wigner ansatz for resonant amplitudes Full resonant amplitude of unitarized Breit-Wigner ansatz is consistent with restrictions imposed by a general unitarity condition, as well as with the resonant Argonne-Osaka ansatz in on-shell approximation.

12. V.I.Mokeev User Group Meeting June 18 2008 12 Cross Sections of the Meson-Baryon Channels Contributing to the  +  - p Electroproduction Q 2 =0.65 GeV 2 Q 2 =0.95 GeV 2 Q 2 =1.30 GeV 2  -  ++  direct +0+0  + D 13 (1520)  + F 13 (1680) pp  -  ++ meson-baryon channel accounts for the major part of  +  - p electroproduction cross section. Relative resonant contribution to  -  ++ channel increases with Q 2. Particular JM model mechanisms becomes relevant in the following W-areas: Channel  -  ++ +0+0  + D 13 (1520)  + F 15 (1680)   P 33 (1600) pp2  direct W, GeV >1.21 >1.45>1.60>1.70 >1.21  direct production decreases substantially at W from 1.5 to 1.7 GeV offering an indication for sizable transition amplitudes between the final  +  - p state and open meson-baryon channels.

13. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 NΔ Transition Form Factors bare quark core CLAS Hall A  Hall C MAMI Bates Meson- Baryon cloud T. Sato and T-S. H. Lee, PRC 63, 055201 (2001). No evidences for pQCD onset at Q 2 <7 GeV 2  Successful description was achieved taking into account meson-baryon dressing and quark core Quadrupole RatiosMagnetic Dipole Form Factor The mechanisms of the meson-baryon dressing pQCD: R EM → 1.0 pQCD: ~1/Q 5 pQCD: R SM → const  Quark core was well described by the relativistic QM: B.Julia-Diaz et al., PRC 69, 035212 (2004).

14. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Quark vs Meson-Baryon Degrees of Freedom in N→  Form Factors Q 2 /m  2 Quark core contribution from DSEQCD: J.Segovia, et al., arXiv:1305.0292[nucl-th]. Contact interaction. Non-perturbative mass generation: contact interaction. contact interaction & quark anomalous magn. moment. projection for quark running mass. bare G* M inferred from exp. data within Argonne-Osaka c.c. approach. G* M (Jones-Scadron) G 1 and G 2 N→  f.f. from LF quark model: I.G.Aznauryan, V.D.Burkert, Phys. Rev. C85, 055202 (2012). quark core. meson-baryon cloud from Argonne-Osaka approach. dressed G 1 and G 2 f.f. For the first time this quark model accounts for momentum dependence of dressed quark mass.

15. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 The P 11 (1440) Structure from the CLAS Electrocoupling Data Light Front quark models: I.G.Aznauryan, The physics analyses of these results revealed the P 11 (1440) structure as a combined contribution of: a) quark core as a first radial excitation of the nucleon 3-quark ground state and b) meson-baryon dressing. Meson-Baryon dressing: (absolute values) A 1/2 S 1/2     p prelim.     p 2012 N  2009 B,Julia-Diaz et al., PRC 77, 045205 (2008). PRC 76, 025212 (2007). S.Capstick and B.D.Keister, PRD 51, 3598 (1995). CLAS data: Consistent values of P 11 (1440) electrocouplings determined in independent analyses of N  and  +  - p exclusive channels strongly support reliable electrocoupling extraction.

16. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Quark Core vs Meson-Baryon Cloud in the Structure of P 11 (1440) Consistent results on the quark core contribution from: A 1/2 Poincare-covariant, symmetry preserving DSEQCD evaluation. Account for quark mass/structure formation in dressing of bare quark by gluon cloud. Simplified contact interaction generates momentum independent quark mass. Measured dressed electrocouplings are substantially different from the estimated quark core contribution. Different data analyses suggest sizable meson-baryon cloud at Q 2 <5.0 GeV 2 which gradually decreases with Q 2. First evaluation of the quark core contribution to the P 11 (1440) electrocouplings starting from QCD Lagrangian within Dyson-Schwinger Equations of QCD: global meson photo-, electro-, and hadroproduction data analysis within EBAC/ Argonne-Osaka approach. D.J.Wilson, et al, Phys. Rev. C85, 025205 (2012). DSEQCD.

17. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013  v NN* Electrocouplings of D 13 (1520) and S 11 (1535) Resonances D 13 (1520) A 1/2 D 13 (1520) A 3/2 S 11 (1535) A 1/2 M.Giannini,E.Santopinto, PRC 86, 065202 (2012). S.Capstick, B..D.Keister, PRD 51, 3598 (1995). MB dressing abs. values (EBAC/Argonne-Osaka) a good agreement between the results from N  N  and  +  - p exclusive channels. access to the lowest orbital excitation of 3-q system and DCSB manifestation through comparison of the ground and S 11 (1535) state structure (chiral partners). contributions from inner quark core and external meson-baryon cloud, which depends substantially on the resonance quantum numbers.  p CLAS, Hall-C

18. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 High lying resonance electrocouplings from the     p CLAS data analysis Δ(1700)D 33 A 1/2     p electroproduction channel provided first preliminary results on S 31 (1620), S 11 (1650), F 15 (1685), D 33 (1700), and P 13 (1720) electrocouplings with good accuracy. N  world V.D.Burkert, et al., PRC 67, 035204 (2003). N  Q 2 =0, CLAS M.Dugger, et al., PRC 79,065206 (2009). A 3/2 N  CLAS preliminary computed from the data on D 13 (1520) and S 11 (1535) electrocouplings within the framework of SQTM approach: I.G. Aznauryan and V.D. Burkert, Progr. Nucl. Part. Phys. 67, 1 (2012). Single quark electromagnetic current and SU(6) spin-flavor symmetry play an important role in the structure and electroexcitation of D 13 (1520), S 11 (1535), and D 33 (1700) states. BF(N  ): 80-90%

19. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 High lying resonance electrocouplings from the     p CLAS data analysis N (1685)F 15 A 1/2 A 3/2 MAID analysis of N  electroproduction L.Tiator et al., Eur. Phys. J. Spec. Top. 198, 141 (2011). The results from     p channel confirmed the previous MAID analysis of N  electroproduction Hypercentral constituent quark model by M.M.Giannini, E.Santopinto, PRC 86, 065202 (2012). Difference between the experimental results and QM expectations is likely related to meson-baryon cloud contributions. Evaluations of meson-baryon cloud contributions to electrocouplings of high mass resonances are needed. Bethe-Salpeter Bonn model by M.Ronninger, B.Ch.Metsch, EPJ A49, 8 (2013). BF(N  ): 65-70% BF(N  ): 30-40%

20. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 High lying resonance electrocouplings from the     p CLAS data analysis A 1/2  (1620)S 31 S 1/2 Hypercentral constituent quark model by M.Giannini,E.Santopinto, PRC 86, 065202 (2012). Bethe-Salpeter Bonn model by M.Ronninger, B.Ch.Metsch, EPJ A49, 8 (2013). Only known N*-state with dominant longitudinal electroexcitation at Q 2 >0.5 GeV 2. This feature is well reproduced within the framework of hypercentral quark model. Data on electrocouplings of most excited proton states in mass range up to 1.8 GeV demonstrated distinctive differences in the structure of resonances of different quantum numbers. The studies of the ground and all prominent excited state structure combined are needed in order to explore the mechanisms of the ground and N*-state formation from quarks and gluons.

21. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 High quality meson electroproduction data from the CLAS detector allowed us to determine electrocouplings of P 33 (1232), P 11 (1440), D 13 (1520), and S 11 (1535) resonances from analyses of N  and N  channels at Q 2 <5.0 GeV 2 and Q 2 <4.0 GeV 2, respectively, as well as from the  +  - p electroproduction at Q 2 <1.5 GeV 2. Consistent values of  v NN* electrocouplings from independent analyses of N  /N  and N  /N  channels confirmed reliable extraction of these fundamental quantities. Preliminary results on electrocouplings of S 31 (1620), S 11 (1650), F 15 (1680), D 33 (1700), and P 13 (1720) resonances were obtained from analysis of  +  - p electroproduction at 0.5<Q 2 <1.5 GeV 2 for the first time. Analyses of  the results on  v NN* electrocouplings revealed the N*-structure as internal core of three constituent quarks surrounded by external meson-baryon cloud. Resonances of different quantum numbers provided complementary information on the N* structure. The data on electrocouplings of all prominent N*-states are needed. Electrocouplings of most N*-states in mass range up to 2.0 GeV will be determined in few years from independent analyses of N  and N  electroproduction at photon virtualities up to 5.0 GeV 2. Conclusions and Outlook

22. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Conclusions and outlook The dedicated experiment on N* studies with the CLAS12 detector at the largest photon virtualities ever achieved 5.0<Q 2 <12 GeV 2 is scheduled for the first year of running after completion of the Jefferson Lab 12 GeV Upgrade Project. The N* program with the CLAS12 detector opens up the prospects to elucidate the emergence of >98 % of nucleon and N* masses from QCD.

23. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Back up

24. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Forward Detector CLAS 12 CLAS 12 CLAS 12 supports a broad program in hadronic physics. Plans to study excited baryons and mesons: Search for hybrid mesons and baryons Spectroscopy of Ξ*, Ω - N* Transition form factors at high Q 2. Central Detector

25. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Resonance Transitions with the CLAS12 12 GeV experiment E12-09-003 will extend access to electrocouplings for all prominent N* states in the range up to Q 2 =12GeV 2. quark mass (GeV) Resonance electrocouplings in regime of quark core dominance can be related to the running quark masses and their dynamical structure. Probe the transition from confinement to pQCD regimes, allowing us to explore how confinement in baryons emerge from QCD and how >98 % of baryon masses are generated non-perturbatively via dynamical chiral symmetry breaking. accessible at 6 GeV accessible at 12 GeV LQCD DSE CLAS12 projected Light front quark model: I.G.Aznauryan, V.D. Burkert, PRC85, 055202 (2012). DSEQCD : contact inte- raction; realistic QCD interaction. P 11 (1440) A 1/2

26. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 I. G. Aznauryan, A. Bashir, V. Braun, S.J. Brodsky, V.D. Burkert, L. Chang, Ch. Chen, B. El-Bennich, I.C. Cloët, P.L. Cole, R.G. Edwards, G.V. Fedotov, M.M. Giannini, R.W. Gothe, F. Gross, Huey-Wen Lin, P. Kroll, T.-S.H. Lee, W. Melnitchouk, V.I. Mokeev, M.T. Peña, G. Ramalho, C.D. Roberts, E. Santopinto, G F. de Teramond, K. Tsushima, D.J. Wilson 27 authors – 99 pages Will be published in Int. J. Mod. Phys. E22, 1330015 (2013). I. G. Aznauryan, A. Bashir, V. Braun, S.J. Brodsky, V.D. Burkert, L. Chang, Ch. Chen, B. El-Bennich, I.C. Cloët, P.L. Cole, R.G. Edwards, G.V. Fedotov, M.M. Giannini, R.W. Gothe, F. Gross, Huey-Wen Lin, P. Kroll, T.-S.H. Lee, W. Melnitchouk, V.I. Mokeev, M.T. Peña, G. Ramalho, C.D. Roberts, E. Santopinto, G F. de Teramond, K. Tsushima, D.J. Wilson 27 authors – 99 pages Will be published in Int. J. Mod. Phys. E22, 1330015 (2013). http://arxiv.org/abs/1212.4891

27. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Evidence for new N* states and couplings State N((mass) J P PDG 2010PDG 2012KΛKΣ Nγ N(1710)1/2 + *** (not seen in GW analysis) *** ***** N(1880)1/2 + ** * N(1895)1/2 - ** **** N(1900)3/2 + ***** ***** N(1875)3/2 - *** ***** N(2150)3/2 - ** N(2000)5/2 + ******* N(2060)5/2 - ******** Bonn-Gatchina Analysis – A.V. Anisovich et al., EPJ A48, 15 (2012) Strong impact from the CLAS KY photoproduction data on the signala from new states New states still need to be confirmed

28. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Why  studies of ground and excited nucleon states combined are needed? Di-quark J  Ground state P 11 ½ + (1440) S 11 ½ - (1535) S 11 ½ - (1650) 0+0+ 77% 1+1+ 23%100% 0-0- 51%43% 1-1- 49%57% N* states of different quantum numbers offer complementary information on mechanisms of baryon generation from quarks and gluons. N* electrocouplings allow us to explore strong regime of QCD at larger transverse distances with larger  s than the ground state form factors. Di-quark content of ground and N* states from DSEQCD with vector x vector interaction, C.D.Roberts et al., AIP Conf. Proc. 1432, 309 (2012). N* spectrum and structure from LQCD, J.J.Dudek, R.G.Edwards, Phys. Rev. D85, 054016 (2012).

29. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Impact of the Recent LQCD studies of N* Spectrum and Structure on the N* Program with CLAS/CLAS12 J.J.Dudek, R.G.Edwards, Phys. Rev. D85, 054016 (2012). each N* state with M N* <1.8 GeV has partner in computed LQCD spectrum, but level ordering is not always consistent to the data wave functions of the low-lying N* states dominate by 1-2 SU(6) configurations, while the wave function of high lying N*’s may contain many SU(6) configurations presence of hybrid-N*s with dominant contribution of hybrid components at M N* >1.9 GeV marked by New direction in N* studies proposed in V.D.Burkert, arXiv:1203.2373 [nucl-ex]: Search for hybrid N*-states looking for:  overpopulation of SU(6)-multiplet;  particular behavior of  v NN* electrocouplings, which reflects presence of the hybrid component. Should be verified by experiment !

30. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 The Approaches for Extraction of  v NN* Electrocouplings from N  Exclusive Electroproduction off Protons I. G.Aznauryan, Phys. Rev. C67, 015209 (2003), I.G.Aznauryan, V. D.Burkert, et al. (CLAS Collaboration), PRC 80. 055203 (2009). ++ p      N N N N N  Unitary Isobar Model (UIM) The Model based on fixed-t Dispersion Relations (DR) the real parts of 18 invariant N  electroproduction amplitudes are computed from their imaginary parts employing model independent fixed-t dispersion relations. the imaginary parts of the N  electroproduction amplitudes at W>1.3 GeV are dominated by resonant parts and were computed from N* parameters fit to the data.

31. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Resonant /non-resonant contributions from the fit of  +  - p electroproduction cross sections within the JM model W=1.51 GeV, Q 2 =0.38 GeV 2 W=1.51 GeV, Q 2 =0.43 GeV 2 full cross sections within the JM model resonant part non-resonant part Reliable isolation of the resonant cross sections is achieved

32. M. Ripani, MENU 2013, Rome, September 30 – October 4, 2013 Transition N-P 11 (1440) form factors in LQCD CLAS data Includes the quark loops in the sea, which are critical in order to reproduce the CLAS data at Q 2 <1.0 GeV 2 M π = 390, 450, 875 MeV L box =3.0, 2.5, 2.5 f Exploratory LQCD results provide reasonable description of the CLAS data from the QCD Lagrangian. Prospects for LQCD evaluation with improved projection operators, approaching physical mp in the box of appropriate size. H.W. Lin and S.D. Cohen, arXiv:1108.2528 A 1/2, S 1/2 => F 1 *, F 2 *

33. V.I.Mokeev User Group Meeting June 18 2008 33  v NN* Electrocouplings: A Unique Window into the Quark Structure Meson-Baryon Dressing absolute meson-baryon cloud amplitudes (EBAC) quark core contributions (constituent quark models) D 13 (1520) Data on  v NN* electrocouplings from E12-09-003 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. CLAS: N  and N  N  combined P 11 (1440)

34. V.I.Mokeev User Group Meeting June 18 2008 34 Anticipated N* Electrocouplings from data on N  & N  electroproduction 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), …  This 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