Recent results from the G⁰ experiment

Conference · Mon Apr 12 04:00:00 EDT 2010 · EPJ Web Proceedings

DOI:https://doi.org/10.1051/epjconf/20100303004· OSTI ID:985382

Real, J S; Armstrong, D S; Arvieux, D S; Bailey, S L; Beck, D H; Beise, E J; Benesch, J; Benmokhtar, F; Bimbot, L; Birchall, J; Bosted, P; Breuer, H; Capuano, C L; Chao, Y -C; Coppens, A; Davis, C A; Ellis, C; Flores, G; Furget, C; Gaskell, D ; Gericke, M.T.W.; Grames, J; Guillard, G; Hansknecht, J; Horn, T; Jones, M; King, P M; Korsch, W; Kox, S; Lee, L; Liu, J; Lung, A; Mammei, J; Martin, J W; McKeown, R D; Micherdzinska, A; Mihovilovic, M; Mkrtchyan, H; Muether, M; van Oers, W.T.H.; Page, S A; Papvassiliou, V; Pate, S F; Phillips, S K; Pillot, P; Pitt, M L; Poelker, M; Quinn, B; Ramsay, W D; Roche, J; Roos, P; Schaub, J; Seva, T; Simicevic, N; Smith, G R; Spayde, D T; Stutzman, M; Suleiman, R; Tadevosyan, V; Versteegen, M; Voutier, E; Vulcan, W; Wells, S P; Williamson, S E; Wood, S A

We have measured parity violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering at backward electron angle. These measurements have been done at two momentum transfers : Q² = 0.22 and 0.63 (GeV/c)² . Together with our previous forward angle measurement [1], we can extract strange quark contributions to the electromagnetic form factors of the nucleon, as well as nucleon axial form factor coming from the neutral weak interaction. The results indicate a strange quark magnetic contribution close to zero at these Q² , and a possible non zero strange quark electric contribution for the high Q² . The first Q² behavior measurement of the nucleon axial form factor in elastic electron scattering shows a good agreement with radiative corrections calculated at Q² = 0 and with a dipole form using the axial mass determined in neutrino scattering.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 985382
• Report Number(s): JLAB-PHY--09-1132; DOE/OR/23177--1269
• Conference Information: Journal Name: EPJ Web Proceedings Journal Volume: 3
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
DIPOLES
ELECTROMAGNETIC FORM FACTORS
ELECTRONS
FORM FACTORS
MOMENTUM TRANSFER
NEUTRINOS
NUCLEONS
PARITY
PHYSICS
QUARKS
RADIATIVE CORRECTIONS
SCATTERING
WEAK INTERACTIONS