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Fomin N, Arrington J, Asaturyan R, Benmokhtar F, Boeglin W, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Daniel A, Day DB, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Gaskell D, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Mkrtchyan H, Navasardyan T, Niculescu G, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Seely J, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. New measurements of high-momentum nucleons and short-range structures in nuclei. PHYSICAL REVIEW LETTERS 2012; 108:092502. [PMID: 22463628 DOI: 10.1103/physrevlett.108.092502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Indexed: 05/31/2023]
Abstract
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate.
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Androić D, Armstrong DS, Arvieux J, Bailey SL, Beck DH, Beise EJ, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano CL, Chao YC, Coppens A, Davis CA, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke MTW, Grames J, Guillard G, Hansknecht J, Horn T, Jones MK, King PM, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin JW, McKeown RD, Micherdzinska A, Mihovilovic M, Mkrtchyan H, Muether M, Page SA, Papavassiliou V, Pate SF, Phillips SK, Pillot P, Pitt ML, Poelker M, Quinn B, Ramsay WD, Real JS, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith GR, Spayde DT, Stutzman M, Suleiman R, Tadevosyan V, van Oers WTH, Versteegen M, Voutier E, Vulcan W, Wells SP, Williamson SE, Wood SA, Pasquini B, Vanderhaeghen M. Transverse beam spin asymmetries at backward angles in elastic electron-proton and quasielastic electron-deuteron scattering. PHYSICAL REVIEW LETTERS 2011; 107:022501. [PMID: 21797598 DOI: 10.1103/physrevlett.107.022501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Indexed: 05/31/2023]
Abstract
We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108°) for Q² = 0.22 GeV²/c² and 0.63 GeV²/c² at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (πN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.
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Riordan S, Abrahamyan S, Craver B, Kelleher A, Kolarkar A, Miller J, Cates GD, Liyanage N, Wojtsekhowski B, Acha A, Allada K, Anderson B, Aniol KA, Annand JRM, Arrington J, Averett T, Beck A, Bellis M, Boeglin W, Breuer H, Calarco JR, Camsonne A, Chen JP, Chudakov E, Coman L, Crowe B, Cusanno F, Day D, Degtyarenko P, Dolph PAM, Dutta C, Ferdi C, Fernández-Ramírez C, Feuerbach R, Fraile LM, Franklin G, Frullani S, Fuchs S, Garibaldi F, Gevorgyan N, Gilman R, Glamazdin A, Gomez J, Grimm K, Hansen JO, Herraiz JL, Higinbotham DW, Holmes R, Holmstrom T, Howell D, de Jager CW, Jiang X, Jones MK, Katich J, Kaufman LJ, Khandaker M, Kelly JJ, Kiselev D, Korsch W, LeRose J, Lindgren R, Markowitz P, Margaziotis DJ, Beck SMT, Mayilyan S, McCormick K, Meziani ZE, Michaels R, Moffit B, Nanda S, Nelyubin V, Ngo T, Nikolenko DM, Norum B, Pentchev L, Perdrisat CF, Piasetzky E, Pomatsalyuk R, Protopopescu D, Puckett AJR, Punjabi VA, Qian X, Qiang Y, Quinn B, Rachek I, Ransome RD, Reimer PE, Reitz B, Roche J, Ron G, Rondon O, Rosner G, Saha A, Sargsian MM, Sawatzky B, Segal J, Shabestari M, Shahinyan A, Shestakov Y, Singh J, Sirca S, Souder P, Stepanyan S, Stibunov V, Sulkosky V, Tajima S, Tobias WA, Udias JM, Urciuoli GM, Vlahovic B, Voskanyan H, Wang K, Wesselmann FR, Vignote JR, Wood SA, Wright J, Yao H, Zhu X. Measurements of the electric form factor of the neutron up to Q2=3.4 GeV2 using the reaction 3He(e,e'n)pp. PHYSICAL REVIEW LETTERS 2010; 105:262302. [PMID: 21231649 DOI: 10.1103/physrevlett.105.262302] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Indexed: 02/05/2023]
Abstract
The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively.
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Fomin N, Arrington J, Day DB, Gaskell D, Daniel A, Seely J, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Miyoshi T, Mkrtchyan H, Navasardyan T, Niculescu G, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. Scaling of the F2 structure function in nuclei and quark distributions at x>1. PHYSICAL REVIEW LETTERS 2010; 105:212502. [PMID: 21231294 DOI: 10.1103/physrevlett.105.212502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 05/30/2023]
Abstract
We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.
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Slifer K, Rondón OA, Aghalaryan A, Ahmidouch A, Asaturyan R, Bloch F, Boeglin W, Bosted P, Carasco C, Carlini R, Cha J, Chen JP, Christy ME, Cole L, Coman L, Crabb D, Danagoulian S, Day D, Dunne J, Elaasar M, Ent R, Fenker H, Frlez E, Gaskell D, Gan L, Gomez J, Hu B, Jourdan J, Jones MK, Keith C, Keppel CE, Khandaker M, Klein A, Kramer L, Liang Y, Lichtenstadt J, Lindgren R, Mack D, McKee P, McNulty D, Meekins D, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Pocanic D, Prok Y, Raue B, Reinhold J, Roche J, Kiselev D, Savvinov N, Sawatzky B, Seely M, Sick I, Smith C, Smith G, Stepanyan S, Tang L, Tajima S, Testa G, Vulcan W, Wang K, Warren G, Wesselmann FR, Wood S, Yan C, Yuan L, Yun J, Zeier M, Zhu H. Probing quark-gluon interactions with transverse polarized scattering. PHYSICAL REVIEW LETTERS 2010; 105:101601. [PMID: 20867509 DOI: 10.1103/physrevlett.105.101601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Revised: 08/24/2010] [Indexed: 05/29/2023]
Abstract
We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.
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Roche J, Stubbs D, Glanz W. Assessment and choice: an operant simulation of foraging in patches. J Exp Anal Behav 2010; 66:327-47. [PMID: 16812828 PMCID: PMC1284579 DOI: 10.1901/jeab.1996.66-327] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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57
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Androić D, Armstrong DS, Arvieux J, Bailey SL, Beck DH, Beise EJ, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano CL, Chao YC, Coppens A, Davis CA, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke MTW, Grames J, Guillard G, Hansknecht J, Horn T, Jones M, King PM, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin JW, McKeown RD, Mihovilovic M, Micherdzinska A, Mkrtchyan H, Muether M, Page SA, Papavassiliou V, Pate SF, Phillips SK, Pillot P, Pitt ML, Poelker M, Quinn B, Ramsay WD, Real JS, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith GR, Spayde DT, Stutzman M, Suleiman R, Tadevosyan V, van Oers WTH, Versteegen M, Voutier E, Vulcan W, Wells SP, Williamson SE, Wood SA. Strange quark contributions to parity-violating asymmetries in the backward angle G0 electron scattering experiment. PHYSICAL REVIEW LETTERS 2010; 104:012001. [PMID: 20366359 DOI: 10.1103/physrevlett.104.012001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Indexed: 05/29/2023]
Abstract
We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q2=0.22 and 0.63 GeV2. They are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of approximately < 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial-vector current at these four-momentum transfers.
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Real J, Androić D, Armstrong D, Arvieux J, Bailey S, Beck D, Beise E, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano C, Chao YC, Coppens A, Davis C, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke M, Grames J, Guillard G, Hansknecht J, Horn T, Jones M, King P, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin J, McKeown R, Micherdzinska A, Mihovilovic M, Mkrtchyan H, Muether M, van Oers W, Page S, Papavassiliou V, Pate S, Phillips S, Pillot P, Pitt M, Poelker M, Quinn B, Ramsay W, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith G, Spayde D, Stutzman M, Suleiman R, Tadevosyan V, Versteegen M, Voutier E, Vulcan W, Wells S, Williamson S, Wood S. Recent results from the G0experiment. EPJ WEB OF CONFERENCES 2010. [DOI: 10.1051/epjconf/20100303004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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59
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Seely J, Daniel A, Gaskell D, Arrington J, Fomin N, Solvignon P, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Clasie B, Connell S, Dalton MM, Day D, Dunne J, Dutta D, El Fassi L, Ent R, Fenker H, Filippone BW, Gao H, Hill C, Holt RJ, Horn T, Hungerford E, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lee C, Lung AF, Malace S, Meekins DG, Mertens T, Mkrtchyan H, Navasardyan T, Niculescu G, Niculescu I, Nomura H, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wesselmann FR, Wood SA, Wright J, Yuan L, Zheng X. New measurements of the European Muon Collaboration effect in very light nuclei. PHYSICAL REVIEW LETTERS 2009; 103:202301. [PMID: 20365978 DOI: 10.1103/physrevlett.103.202301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 07/27/2009] [Indexed: 05/29/2023]
Abstract
New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.
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Karayan-Tapon L, Wager M, Guilhot J, Levillain P, Marquant C, Clarhaut J, Potiron V, Roche J. Semaphorin, neuropilin and VEGF expression in glial tumours: SEMA3G, a prognostic marker? Br J Cancer 2008; 99:1153-60. [PMID: 18781179 PMCID: PMC2567090 DOI: 10.1038/sj.bjc.6604641] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Gliomas are characterised by local infiltration, migration of tumour cells across long distances and sustained angiogenesis; therefore, proteins involved in these processes are most likely important. Such candidates are semaphorins involved in axon guidance and cell migration. In addition, semaphorins regulate tumour progression and angiogenesis. For cell signalling, class-4 semaphorins bind directly to plexins, whereas class-3 semaphorins require additional neuropilin (NRP) receptors that also bind VEGF165. The anti-angiogenic activity of class-3 semaphorins can be explained by competition with VEGF165 for NRP binding. In this study, we analysed the expressions of seven semaphorins of class-3, SEMA4D, VEGF and the NRP1 and NRP2 receptors in 38 adult glial tumours. In these tumours, SEMA3B, SEMA3G and NRP2 expressions were related to prolonged survival. In addition, SEMA3D expression was reduced in high-grade as compared with low-grade gliomas. In contrast, VEGF correlated with higher grade and poor survival. Thus, our data suggest a function for a subset of class-3 semaphorins as inhibitors of tumour progression, and the prognostic value of the VEGF/SEMA3 balance in adult gliomas. Moreover, in multivariate analysis, SEMA3G was found to be the only significant prognostic marker.
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Roche J, Potiron V, Nasarre P, Sharma G, Gemmill R, Drabkin H. SEMA3F Semaphorin is involved in tumor angiogenesis. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71270-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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62
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63
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64
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Mazouz M, Camsonne A, Camacho CM, Ferdi C, Gavalian G, Kuchina E, Amarian M, Aniol KA, Beaumel M, Benaoum H, Bertin P, Brossard M, Chen JP, Chudakov E, Craver B, Cusanno F, de Jager CW, Deur A, Feuerbach R, Fieschi JM, Frullani S, Garçon M, Garibaldi F, Gayou O, Gilman R, Gomez J, Gueye P, Guichon PAM, Guillon B, Hansen O, Hayes D, Higinbotham D, Holmstrom T, Hyde CE, Ibrahim H, Igarashi R, Jiang X, Jo HS, Kaufman LJ, Kelleher A, Kolarkar A, Kumbartzki G, Laveissiere G, Lerose JJ, Lindgren R, Liyanage N, Lu HJ, Margaziotis DJ, Meziani ZE, McCormick K, Michaels R, Michel B, Moffit B, Monaghan P, Nanda S, Nelyubin V, Potokar M, Qiang Y, Ransome RD, Réal JS, Reitz B, Roblin Y, Roche J, Sabatié F, Saha A, Sirca S, Slifer K, Solvignon P, Subedi R, Sulkosky V, Ulmer PE, Voutier E, Wang K, Weinstein LB, Wojtsekhowski B, Zheng X, Zhu L. Deeply virtual compton scattering off the neutron. PHYSICAL REVIEW LETTERS 2007; 99:242501. [PMID: 18233443 DOI: 10.1103/physrevlett.99.242501] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Indexed: 05/25/2023]
Abstract
The present experiment exploits the interference between the deeply virtual Compton scattering (DVCS) and the Bethe-Heitler processes to extract the imaginary part of DVCS amplitudes on the neutron and on the deuteron from the helicity-dependent D(e,e'gamma)X cross section measured at Q2=1.9 GeV2 and xB=0.36. We extract a linear combination of generalized parton distributions (GPDs) particularly sensitive to E_{q}, the least constrained GPD. A model dependent constraint on the contribution of the up and down quarks to the nucleon spin is deduced.
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65
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Ron G, Glister J, Lee B, Allada K, Armstrong W, Arrington J, Beck A, Benmokhtar F, Berman BL, Boeglin W, Brash E, Camsonne A, Calarco J, Chen JP, Choi S, Chudakov E, Coman L, Craver B, Cusanno F, Dumas J, Dutta C, Feuerbach R, Freyberger A, Frullani S, Garibaldi F, Gilman R, Hansen O, Higinbotham DW, Holmstrom T, Hyde CE, Ibrahim H, Ilieva Y, de Jager CW, Jiang X, Jones MK, Kang H, Kelleher A, Khrosinkova E, Kuchina E, Kumbartzki G, LeRose JJ, Lindgren R, Markowitz P, May-Tal Beck S, McCullough E, Meekins D, Meziane M, Meziani ZE, Michaels R, Moffit B, Norum BE, Oh Y, Olson M, Paolone M, Paschke K, Perdrisat CF, Piasetzky E, Potokar M, Pomatsalyuk R, Pomerantz I, Puckett A, Punjabi V, Qian X, Qiang Y, Ransome R, Reyhan M, Roche J, Rousseau Y, Saha A, Sarty AJ, Sawatzky B, Schulte E, Shabestari M, Shahinyan A, Shneor R, Sirca S, Slifer K, Solvignon P, Song J, Sparks R, Subedi R, Strauch S, Urciuoli GM, Wang K, Wojtsekhowski B, Yan X, Yao H, Zhan X, Zhu X. Measurements of the proton elastic-form-factor ratio mu pG p E/G p M at low momentum transfer. PHYSICAL REVIEW LETTERS 2007; 99:202002. [PMID: 18233135 DOI: 10.1103/physrevlett.99.202002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2007] [Indexed: 05/25/2023]
Abstract
High-precision measurements of the proton elastic form-factor ratio, mu pG p E/G p M, have been made at four-momentum transfer, Q2, values between 0.2 and 0.5 GeV2. The new data, while consistent with previous results, clearly show a ratio less than unity and significant differences from the central values of several recent phenomenological fits. By combining the new form-factor ratio data with an existing cross-section measurement, one finds that in this Q2 range the deviation from unity is primarily due to G p E being smaller than expected.
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66
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Young RD, Carlini RD, Thomas AW, Roche J. Testing the standard model by precision measurement of the weak charges of quarks. PHYSICAL REVIEW LETTERS 2007; 99:122003. [PMID: 17930499 DOI: 10.1103/physrevlett.99.122003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Indexed: 05/25/2023]
Abstract
In a global analysis of the latest parity-violating electron scattering measurements on nuclear targets, we demonstrate a significant improvement in the experimental knowledge of the weak neutral-current lepton-quark interactions at low energy. The precision of this new result, combined with earlier atomic parity-violation measurements, places tight constraints on the size of possible contributions from physics beyond the standard model. Consequently, this result improves the lower-bound on the scale of relevant new physics to approximately 1 TeV.
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67
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Armstrong DS, Arvieux J, Asaturyan R, Averett T, Bailey SL, Batigne G, Beck DH, Beise EJ, Benesch J, Bimbot L, Birchall J, Biselli A, Bosted P, Boukobza E, Breuer H, Carlini R, Carr R, Chant N, Chao YC, Chattopadhyay S, Clark R, Covrig S, Cowley A, Dale D, Davis C, Falk W, Finn JM, Forest T, Franklin G, Furget C, Gaskell D, Grames J, Griffioen KA, Grimm K, Guillon B, Guler H, Hannelius L, Hasty R, Allen AH, Horn T, Johnston K, Jones M, Kammel P, Kazimi R, King PM, Kolarkar A, Korkmaz E, Korsch W, Kox S, Kuhn J, Lachniet J, Lee L, Lenoble J, Liatard E, Liu J, Loupias B, Lung A, Marchand D, Martin JW, McFarlane KW, McKee DW, McKeown RD, Merchez F, Mkrtchyan H, Moffit B, Morlet M, Nakagawa I, Nakahara K, Neveling R, Ong S, Page S, Papavassiliou V, Pate SF, Phillips SK, Pitt ML, Poelker M, Porcelli TA, Quéméner G, Quinn B, Ramsay WD, Rauf AW, Real JS, Roche J, Roos P, Rutledge GA, Secrest J, Simicevic N, Smith GR, Spayde DT, Stepanyan S, Stutzman M, Sulkosky V, Tadevosyan V, Tieulent R, Van de Wiele J, van Oers WTH, Voutier E, Vulcan W, Warren G, Wells SP, Williamson SE, Wood SA, Yan C, Yun J, Zeps V. Transverse beam spin asymmetries in forward-angle elastic electron-proton scattering. PHYSICAL REVIEW LETTERS 2007; 99:092301. [PMID: 17930999 DOI: 10.1103/physrevlett.99.092301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Indexed: 05/25/2023]
Abstract
We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2=0.15, 0.25 (GeV/c)2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A(n) provides a direct probe of the imaginary component of the 2gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.
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Serment M, Roche J, De Monredon J, Stopek D, Gitteau Lala E, Pisella P. 581 Le Chikungunya et l’œil : données acquises au cours de l’épidémie de La Réunion. J Fr Ophtalmol 2007. [DOI: 10.1016/s0181-5512(07)80394-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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69
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Wesselmann FR, Slifer K, Tajima S, Aghalaryan A, Ahmidouch A, Asaturyan R, Bloch F, Boeglin W, Bosted P, Carasco C, Carlini R, Cha J, Chen JP, Christy ME, Cole L, Coman L, Crabb D, Danagoulian S, Day D, Dunne J, Elaasar M, Ent R, Fenker H, Frlez E, Gan L, Gaskell D, Gomez J, Hu B, Jones MK, Jourdan J, Keith C, Keppel CE, Khandaker M, Klein A, Kramer L, Liang Y, Lichtenstadt J, Lindgren R, Mack D, McKee P, McNulty D, Meekins D, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Pocanic D, Prok Y, Raue B, Reinhold J, Roche J, Rohe D, Rondón OA, Savvinov N, Sawatzky B, Seely M, Sick I, Smith C, Smith G, Stepanyan S, Tang L, Testa G, Vulcan W, Wang K, Warren G, Wood S, Yan C, Yuan L, Yun J, Zeier M, Zhu H. Proton spin structure in the resonance region. PHYSICAL REVIEW LETTERS 2007; 98:132003. [PMID: 17501192 DOI: 10.1103/physrevlett.98.132003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/15/2023]
Abstract
We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV<W<1.910 GeV) at an average four momentum transfer of Q2=1.3 GeV2. Using the Jefferson Lab polarized electron beam, a spectrometer, and a polarized solid target, we measured the asymmetries A|| and A(perpendicular) to high precision, and extracted the asymmetries A1 and A2, and the spin structure functions g1 and g2. We found a notably nonzero A(perpendicular), significant contributions from higher-twist effects, and only weak support for polarized quark-hadron duality.
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70
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Acha A, Aniol KA, Armstrong DS, Arrington J, Averett T, Bailey SL, Barber J, Beck A, Benaoum H, Benesch J, Bertin PY, Bosted P, Butaru F, Burtin E, Cates GD, Chao YC, Chen JP, Chudakov E, Cisbani E, Craver B, Cusanno F, De Leo R, Decowski P, Deur A, Feuerbach RJ, Finn JM, Frullani S, Fuchs SA, Fuoti K, Gilman R, Glesener LE, Grimm K, Grames JM, Hansen JO, Hansknecht J, Higinbotham DW, Holmes R, Holmstrom T, Ibrahim H, de Jager CW, Jiang X, Katich J, Kaufman LJ, Kelleher A, King PM, Kolarkar A, Kowalski S, Kuchina E, Kumar KS, Lagamba L, LaViolette P, LeRose J, Lindgren RA, Lhuillier D, Liyanage N, Margaziotis DJ, Markowitz P, Meekins DG, Meziani ZE, Michaels R, Moffit B, Nanda S, Nelyubin V, Otis K, Paschke KD, Phillips SK, Poelker M, Pomatsalyuk R, Potokar M, Prok Y, Puckett A, Qian X, Qiang Y, Reitz B, Roche J, Saha A, Sawatzky B, Singh J, Slifer K, Sirca S, Snyder R, Solvignon P, Souder PA, Stutzman ML, Subedi R, Suleiman R, Sulkosky V, Tobias WA, Ulmer PE, Urciuoli GM, Wang K, Whitbeck A, Wilson R, Wojtsekhowski B, Yao H, Ye Y, Zhan X, Zheng X, Zhou S, Ziskin V. Precision measurements of the nucleon strange form factors at Q2 approximately 0.1 GeV2. PHYSICAL REVIEW LETTERS 2007; 98:032301. [PMID: 17358678 DOI: 10.1103/physrevlett.98.032301] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Indexed: 05/14/2023]
Abstract
We report new measurements of the parity-violating asymmetry A(PV) in elastic scattering of 3 GeV electrons off hydrogen and 4He targets with <theta(lab)> approximately 6.0 degrees . The 4He result is A(PV)=(+6.40+/-0.23(stat)+/-0.12(syst))x10(-6). The hydrogen result is A(PV)=(-1.58+/-0.12(stat)+/-0.04(syst))x10(-6). These results significantly improve constraints on the electric and magnetic strange form factors G(E)(s) and G(M)(s). We extract G(E)(s)=0.002+/-0.014+/-0.007 at <Q(2)>=0.077 GeV2, and G(E)(s)+0.09G(M)(s)=0.007+/-0.011+/-0.006 at <Q(2)>=0.109 GeV2, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions.
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71
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Navasardyan T, Adams GS, Ahmidouch A, Angelescu T, Arrington J, Asaturyan R, Baker OK, Benmouna N, Bertoncini C, Blok HP, Boeglin WU, Bosted PE, Breuer H, Christy ME, Connell SH, Cui Y, Dalton MM, Danagoulian S, Day D, Dodario T, Dunne JA, Dutta D, El Khayari N, Ent R, Fenker HC, Frolov VV, Gan L, Gaskell D, Hafidi K, Hinton W, Holt RJ, Horn T, Huber GM, Hungerford E, Jiang X, Jones M, Joo K, Kalantarians N, Kelly JJ, Keppel CE, Kubarovski V, Li Y, Liang Y, Malace S, Markowitz P, McGrath E, McKee P, Meekins DG, Mkrtchyan H, Moziak B, Niculescu G, Niculescu I, Opper AK, Ostapenko T, Reimer P, Reinhold J, Roche J, Rock SE, Schulte E, Segbefia E, Smith C, Smith GR, Stoler P, Tadevosyan V, Tang L, Ungaro M, Uzzle A, Vidakovic S, Villano A, Vulcan WF, Wang M, Warren G, Wesselmann F, Wojtsekhowski B, Wood SA, Xu C, Yuan L, Zheng X, Zhu H. Onset of quark-hadron duality in pion electroproduction. PHYSICAL REVIEW LETTERS 2007; 98:022001. [PMID: 17358596 DOI: 10.1103/physrevlett.98.022001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Indexed: 05/14/2023]
Abstract
A large data set of charged-pion (pi+/-) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-->pion production mechanisms.
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72
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Gillette Guyonnet S, Abellan Van Kan G, Alix E, Andrieu S, Belmin J, Berrut G, Bonnefoy M, Brocker P, Constans T, Ferry M, Ghisolfi-Marque A, Girard L, Gonthier R, Guerin O, Hervy MP, Jouanny P, Laurain MC, Lechowski L, Nourhashemi F, Raynaud-Simon A, Ritz P, Roche J, Rolland Y, Salva T, Vellas B. IANA (International Academy on Nutrition and Aging) Expert Group: weight loss and Alzheimer's disease. J Nutr Health Aging 2007; 11:38-48. [PMID: 17315079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Weight loss, together with psychological and behavioural symptoms and problems of mobility, is one of the principal manifestations of Alzheimer's disease (AD). Weight loss may be associated with protein and energy malnutrition leading to severe complications (alteration of the immune system, muscular atrophy, loss of independence). Various explanations have been proposed such as atrophy of the mesial temporal cortex, biological disturbances, or feeding behaviours; however, none has been proven. Prevention of weight loss in AD is a major issue. It requires regular follow-up and must be an integral part of the care plan. The aim of this article is to review the present state of scientific knowledge on weight loss associated with AD. We will consider four points: the natural history of weight loss, its known etiological factors, its consequences and the various management options.
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73
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Camacho CM, Camsonne A, Mazouz M, Ferdi C, Gavalian G, Kuchina E, Amarian M, Aniol KA, Beaumel M, Benaoum H, Bertin P, Brossard M, Chen JP, Chudakov E, Craver B, Cusanno F, de Jager CW, Deur A, Feuerbach R, Fieschi JM, Frullani S, Garçon M, Garibaldi F, Gayou O, Gilman R, Gomez J, Gueye P, Guichon PAM, Guillon B, Hansen O, Hayes D, Higinbotham D, Holmstrom T, Hyde-Wright CE, Ibrahim H, Igarashi R, Jiang X, Jo HS, Kaufman LJ, Kelleher A, Kolarkar A, Kumbartzki G, Laveissière G, Lerose JJ, Lindgren R, Liyanage N, Lu HJ, Margaziotis DJ, Meziani ZE, McCormick K, Michaels R, Michel B, Moffit B, Monaghan P, Nanda S, Nelyubin V, Potokar M, Qiang Y, Ransome RD, Réal JS, Reitz B, Roblin Y, Roche J, Sabatié F, Saha A, Sirca S, Slifer K, Solvignon P, Subedi R, Sulkosky V, Ulmer PE, Voutier E, Wang K, Weinstein LB, Wojtsekhowski B, Zheng X, Zhu L. Scaling tests of the cross section for deeply virtual Compton scattering. PHYSICAL REVIEW LETTERS 2006; 97:262002. [PMID: 17280421 DOI: 10.1103/physrevlett.97.262002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Indexed: 05/13/2023]
Abstract
We present the first measurements of the e[over -->]p-->epgamma cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q(2) dependence (from 1.5 to 2.3 GeV(2)) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q(2). The helicity-independent cross section is also measured at Q(2)=2.3 GeV(2). We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation.
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74
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Roche J, Vignaendra D. Midline septa in the lumbo-sacral thecal sac: Acquired abnormality or developmental anomaly? The equivalent of diastematomyelia occurring below the spinal cord? ACTA ACUST UNITED AC 2006; 50:553-62. [PMID: 17107527 DOI: 10.1111/j.1440-1673.2006.01652.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Careful analysis of over 400 patients radiologically diagnosed with arachnoiditis showed a subgroup of eight patients with a specific set of imaging signs that suggest a pre-existing developmental abnormality mimicking the appearance of arachnoiditis. These cases have been collected over a 15-year period. No autopsy or surgical proof is available. All patients have (i) the presence of a well-defined midline septum in the sagittal plane that splits the thecal sac, usually symmetrically, in the lower lumbar or sacral region, below the level of the spinal cord; (ii) the absence of adjacent epidural fibrosis that one would expect if the septation had been caused by surgical intervention or trauma; (iii) the preservation of cerebrospinal fluid within the nerve root sheaths and around the nerve roots at the level of the septation; and in four cases (iv) the presence of either calcification or bone in this midline septum, yet nowhere else in the theca or epidural space. These cases suggest a developmental variant called, for want of a better term, 'split lumbo-sacral thecal sac' analogous to diastematomyelia but not involving the spinal cord. This variant is potentially confused with arachnoiditis or thecal scarring in the lumbo-sacral sac.
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Horn T, Aniol K, Arrington J, Barrett B, Beise EJ, Blok HP, Boeglin W, Brash EJ, Breuer H, Chang CC, Christy ME, Ent R, Gaskell D, Gibson E, Holt RJ, Huber GM, Jin S, Jones MK, Keppel CE, Kim W, King PM, Kovaltchouk V, Liu J, Lolos GJ, Mack DJ, Margaziotis DJ, Markowitz P, Matsumura A, Meekins D, Miyoshi T, Mkrtchyan H, Niculescu I, Okayasu Y, Pentchev L, Perdrisat C, Potterveld D, Punjabi V, Reimer P, Reinhold J, Roche J, Roos PG, Sarty A, Smith GR, Tadevosyan V, Tang LG, Tvaskis V, Vidakovic S, Volmer J, Vulcan W, Warren G, Wood SA, Xu C, Zheng X. Determination of the pion charge form factor at Q2=1.60 and 2.45 (GeV/c)2. PHYSICAL REVIEW LETTERS 2006; 97:192001. [PMID: 17155616 DOI: 10.1103/physrevlett.97.192001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Indexed: 05/12/2023]
Abstract
The 1H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F(pi)) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F(pi) is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative quantum chromodynamics prediction.
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