Abstract
The transverse-target single-spin asymmetry for inclusive deep-inelastic scattering with effectively unpolarized electron and positron beams off a transversely polarized hydrogen target was measured, with the goal of searching for a two-photon exchange signal in the kinematic range 0.007<xB<0.9 and 0.25GeV2<Q2<20GeV2. In two separate regions Q2>1GeV2 and Q2<1GeV2, and for both electron and positron beams, the asymmetries are found to be consistent with zero within statistical and systematic uncertainties, which are of order 10−3 for the asymmetries integrated over xB.
Highlights
The transverse-target single-spin asymmetry for inclusive deep-inelastic scattering with effectively unpolarized electron and positron beams off a transversely polarized hydrogen target was measured, with the goal of searching for a two-photon exchange signal in the kinematic range 0.007 < < 0.9 and 0.25 GeV2 < 2 < 20 GeV2
Two-photon exchange effects are believed to be the best candidate to explain the discrepancy in the measurement of the ratio / of the electric and magnetic form factors of the proton obtained at large fourmomentum transfer between the Rosenbluth method and the polarization transfer method [1]
This is enough to explain most of the discrepancy between the results of the two methods [2, 3], none of the recent calculations can fully resolve the discrepancy at all momentum transfers [4]
Summary
The transverse-target single-spin asymmetry for inclusive deep-inelastic scattering with effectively unpolarized electron and positron beams off a transversely polarized hydrogen target was measured, with the goal of searching for a two-photon exchange signal in the kinematic range 0.007 < < 0.9 and 0.25 GeV2 < 2 < 20 GeV2. In two separate regions 2 > 1 GeV2 and 2 < 1 GeV2, and for both electron and positron beams, the asymmetries are found to be consistent with zero within statistical and systematic uncertainties, which are of order 10−3 for the asymmetries integrated over .
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
