Transverse Beam Spin Asymmetries in Forward-Angle Elastic
  Electron-Proton Scattering

Armstrong, D.S.; Arvieux, J.; Asaturyan, R.; Averett, T.; Bailey, S.L.; Batigne, Guillaume; Beck, D.H.; Beise, E.J.; Benesch, J.; Bimbot, L.; Birchall, J.; Biselli, A.; Bosted, P.; Boukobza, E.; Breuer, H.; Carlini, R.; Carr, R.; Chant, N.; Chao, Y.-C.; Chattopadhyay, S.; Clark, R.; Covrig, S.; Cowley, A.; Dale, D.; Davis, C.; Falk, W.; Finn, J.M.; Forest, T.; Franklin, G.; Furget, C.; Gaskell, D.; Grames, J.; Griffioen, K.A.; Grimm, K.; Guillon, B.; Guler, H.; Hannelius, L.; Hasty, R.; Hawthorne Allen, A.; Horn, T.; Johnston, K.; Jones, M.,; Kammel, P.; Kazimi, R.; King, P.M.; 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, J.W.; Mcfarlane, K.W.; Mckee, D.W.; McKeown, R.D.; Merchez, F.; Mkrtchyan, H.; Moffit, B.; Morlet, M.; Nakagawa, I.; Nakahara, K.; Neveling, R.; Niccolai, S.; Ong, S.; Page, S.; Papavassiliou, V.; Pate, S.F.; Phillips, S.K.; Pitt, M.L.; Poelker, M.; Porcelli, T.A.; Quinn, B.; Quéméner, G.; Ramsay, W.D.; Rauf, A.W.; Roche, J.; Roos, P.; Rutledge, G.A.; Réal, J.S.; Secrest, J.; Simicevic, N.; Smith, G.R.; Spayde, D.T.; Stepanyan, S.; Stutzman, M.; Sulkosky, V.; Tadevosyan, V.; Tieulent, R.; Van De Wiele, J.; Van Oers, W.; Voutier, E.; Vulcan, W.; Warren, G.; Wells, S.P.; Williamson, S.E.; Wood, S.A.; Yan, C.; Yun, J.; Zeps, V.

research

Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering

Authors: D.S. Armstrong
J. Arvieux
R. Asaturyan
T. Averett
S.L. Bailey
Guillaume Batigne
D.H. Beck
E.J. Beise
J. Benesch
L. Bimbot
J. Birchall
A. Biselli
P. Bosted
E. Boukobza
H. Breuer
R. Carlini
R. Carr
N. Chant
Y.-C. Chao
S. Chattopadhyay
R. Clark
S. Covrig
A. Cowley
D. Dale
C. Davis
W. Falk
J.M. Finn
T. Forest
G. Franklin
C. Furget
D. Gaskell
J. Grames
K.A. Griffioen
K. Grimm
B. Guillon
H. Guler
L. Hannelius
R. Hasty
A. Hawthorne Allen
T. Horn
K. Johnston
M., Jones
P. Kammel
R. Kazimi
P.M. King
A. Kolarkar
E. Korkmaz
W. Korsch
S. Kox
J. Kuhn
J. Lachniet
L. Lee
J. Lenoble
E. Liatard
J. Liu
B. Loupias
A. Lung
D. Marchand
J.W. Martin
K.W. Mcfarlane
D.W. Mckee
R.D. McKeown
F. Merchez
H. Mkrtchyan
B. Moffit
M. Morlet
I. Nakagawa
K. Nakahara
R. Neveling
S. Niccolai
S. Ong
S. Page
V. Papavassiliou
S.F. Pate
S.K. Phillips
M.L. Pitt
M. Poelker
T.A. Porcelli
B. Quinn
G. Quéméner
W.D. Ramsay
A.W. Rauf
J. Roche
P. Roos
G.A. Rutledge
J.S. Réal
J. Secrest
N. Simicevic
G.R. Smith
D.T. Spayde
S. Stepanyan
M. Stutzman
V. Sulkosky
V. Tadevosyan
R. Tieulent
J. Van De Wiele
W. Van Oers
E. Voutier
W. Vulcan
G. Warren
S.P. Wells
S.E. Williamson
S.A. Wood
C. Yan
J. Yun
V. Zeps
Publication date: 1 January 2007
Publisher: 'American Physical Society (APS)'
Doi

Abstract

We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely-polarized 3 GeV electrons from unpolarized protons at Q^2 = 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 2-gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.Comment: 5 pages, 3 figures, submitted to Physical Review Letters; shortened to meet PRL length limit, clarified some text after referee's comment