title: Search for effects beyond the born approximation in polarization transfer observables in e(over→)p elastic scattering.
abstract: Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, G(E)/G(M), obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic H(e[over →],e(')p[over →]) reaction for three different beam energies at a Q(2)=2.5  GeV(2), spanning a wide range of the kinematic parameter ε. The ratio R, which equals μ(p)G(E)/G(M) in the Born approximation, is found to be independent of ε at the 1.5% level. The ε dependence of the longitudinal polarization transfer component P(ℓ) shows an enhancement of (2.3±0.6)% relative to the Born approximation at large ε.
authors.affiliation: The College of William and Mary, Williamsburg, Virginia 23187, USA. mezianem@jlab.org
authors.forename: M
authors.initials: M
authors.lastname: Meziane
authors.forename: E J
authors.initials: EJ
authors.lastname: Brash
authors.forename: R
authors.initials: R
authors.lastname: Gilman
authors.forename: M K
authors.initials: MK
authors.lastname: Jones
authors.forename: W
authors.initials: W
authors.lastname: Luo
authors.forename: L
authors.initials: L
authors.lastname: Pentchev
authors.forename: C F
authors.initials: CF
authors.lastname: Perdrisat
authors.forename: A J R
authors.initials: AJ
authors.lastname: Puckett
authors.forename: V
authors.initials: V
authors.lastname: Punjabi
authors.forename: F R
authors.initials: FR
authors.lastname: Wesselmann
authors.forename: A
authors.initials: A
authors.lastname: Ahmidouch
authors.forename: I
authors.initials: I
authors.lastname: Albayrak
authors.forename: K A
authors.initials: KA
authors.lastname: Aniol
authors.forename: J
authors.initials: J
authors.lastname: Arrington
authors.forename: A
authors.initials: A
authors.lastname: Asaturyan
authors.forename: O
authors.initials: O
authors.lastname: Ates
authors.forename: H
authors.initials: H
authors.lastname: Baghdasaryan
authors.forename: F
authors.initials: F
authors.lastname: Benmokhtar
authors.forename: W
authors.initials: W
authors.lastname: Bertozzi
authors.forename: L
authors.initials: L
authors.lastname: Bimbot
authors.forename: P
authors.initials: P
authors.lastname: Bosted
authors.forename: W
authors.initials: W
authors.lastname: Boeglin
authors.forename: C
authors.initials: C
authors.lastname: Butuceanu
authors.forename: P
authors.initials: P
authors.lastname: Carter
authors.forename: S
authors.initials: S
authors.lastname: Chernenko
authors.forename: E
authors.initials: E
authors.lastname: Christy
authors.forename: M
authors.initials: M
authors.lastname: Commisso
authors.forename: J C
authors.initials: JC
authors.lastname: Cornejo
authors.forename: S
authors.initials: S
authors.lastname: Covrig
authors.forename: S
authors.initials: S
authors.lastname: Danagoulian
authors.forename: A
authors.initials: A
authors.lastname: Daniel
authors.forename: A
authors.initials: A
authors.lastname: Davidenko
authors.forename: D
authors.initials: D
authors.lastname: Day
authors.forename: S
authors.initials: S
authors.lastname: Dhamija
authors.forename: D
authors.initials: D
authors.lastname: Dutta
authors.forename: R
authors.initials: R
authors.lastname: Ent
authors.forename: S
authors.initials: S
authors.lastname: Frullani
authors.forename: H
authors.initials: H
authors.lastname: Fenker
authors.forename: E
authors.initials: E
authors.lastname: Frlez
authors.forename: F
authors.initials: F
authors.lastname: Garibaldi
authors.forename: D
authors.initials: D
authors.lastname: Gaskell
authors.forename: S
authors.initials: S
authors.lastname: Gilad
authors.forename: Y
authors.initials: Y
authors.lastname: Goncharenko
authors.forename: K
authors.initials: K
authors.lastname: Hafidi
authors.forename: D
authors.initials: D
authors.lastname: Hamilton
authors.forename: D W
authors.initials: DW
authors.lastname: Higinbotham
authors.forename: W
authors.initials: W
authors.lastname: Hinton
authors.forename: T
authors.initials: T
authors.lastname: Horn
authors.forename: B
authors.initials: B
authors.lastname: Hu
authors.forename: J
authors.initials: J
authors.lastname: Huang
authors.forename: G M
authors.initials: GM
authors.lastname: Huber
authors.forename: E
authors.initials: E
authors.lastname: Jensen
authors.forename: H
authors.initials: H
authors.lastname: Kang
authors.forename: C
authors.initials: C
authors.lastname: Keppel
authors.forename: M
authors.initials: M
authors.lastname: Khandaker
authors.forename: P
authors.initials: P
authors.lastname: King
authors.forename: D
authors.initials: D
authors.lastname: Kirillov
authors.forename: M
authors.initials: M
authors.lastname: Kohl
authors.forename: V
authors.initials: V
authors.lastname: Kravtsov
authors.forename: G
authors.initials: G
authors.lastname: Kumbartzki
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: V
authors.initials: V
authors.lastname: Mamyan
authors.forename: D J
authors.initials: DJ
authors.lastname: Margaziotis
authors.forename: P
authors.initials: P
authors.lastname: Markowitz
authors.forename: A
authors.initials: A
authors.lastname: Marsh
authors.forename: Y
authors.initials: Y
authors.lastname: Matulenko
authors.forename: J
authors.initials: J
authors.lastname: Maxwell
authors.forename: G
authors.initials: G
authors.lastname: Mbianda
authors.forename: D
authors.initials: D
authors.lastname: Meekins
authors.forename: Y
authors.initials: Y
authors.lastname: Melnik
authors.forename: J
authors.initials: J
authors.lastname: Miller
authors.forename: A
authors.initials: A
authors.lastname: Mkrtchyan
authors.forename: H
authors.initials: H
authors.lastname: Mkrtchyan
authors.forename: B
authors.initials: B
authors.lastname: Moffit
authors.forename: O
authors.initials: O
authors.lastname: Moreno
authors.forename: J
authors.initials: J
authors.lastname: Mulholland
authors.forename: A
authors.initials: A
authors.lastname: Narayan
authors.lastname: Nuruzzaman
authors.forename: S
authors.initials: S
authors.lastname: Nedev
authors.forename: E
authors.initials: E
authors.lastname: Piasetzky
authors.forename: W
authors.initials: W
authors.lastname: Pierce
authors.forename: N M
authors.initials: NM
authors.lastname: Piskunov
authors.forename: Y
authors.initials: Y
authors.lastname: Prok
authors.forename: R D
authors.initials: RD
authors.lastname: Ransome
authors.forename: D S
authors.initials: DS
authors.lastname: Razin
authors.forename: P E
authors.initials: PE
authors.lastname: Reimer
authors.forename: J
authors.initials: J
authors.lastname: Reinhold
authors.forename: O
authors.initials: O
authors.lastname: Rondon
authors.forename: M
authors.initials: M
authors.lastname: Shabestari
authors.forename: A
authors.initials: A
authors.lastname: Shahinyan
authors.forename: K
authors.initials: K
authors.lastname: Shestermanov
authors.forename: S
authors.initials: S
authors.lastname: Širca
authors.forename: I
authors.initials: I
authors.lastname: Sitnik
authors.forename: L
authors.initials: L
authors.lastname: Smykov
authors.forename: G
authors.initials: G
authors.lastname: Smith
authors.forename: L
authors.initials: L
authors.lastname: Solovyev
authors.forename: P
authors.initials: P
authors.lastname: Solvignon
authors.forename: R
authors.initials: R
authors.lastname: Subedi
authors.forename: R
authors.initials: R
authors.lastname: Suleiman
authors.forename: E
authors.initials: E
authors.lastname: Tomasi-Gustafsson
authors.forename: A
authors.initials: A
authors.lastname: Vasiliev
authors.forename: M
authors.initials: M
authors.lastname: Vanderhaeghen
authors.forename: M
authors.initials: M
authors.lastname: Veilleux
authors.forename: B B
authors.initials: BB
authors.lastname: Wojtsekhowski
authors.forename: S
authors.initials: S
authors.lastname: Wood
authors.forename: Z
authors.initials: Z
authors.lastname: Ye
authors.forename: Y
authors.initials: Y
authors.lastname: Zanevsky
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: X
authors.initials: X
authors.lastname: Zheng
authors.forename: L
authors.initials: L
authors.lastname: Zhu