Measurements of the magnetic form factor of the proton for timelike momentum transfers

Abstract

Fermilab experiment E835 has measured the cross section for the reaction (p) over barp --> e(+)e(-) at s = 11.63, 12.43, 14.40 and 18.22 GeV2. From the analysis of the 66 observed events new high-precision measurements of the proton magnetic form factor are obtained. (C) 2003 Published by Elsevier Science B.V

Feasibility study for the measurement of πN transition distribution amplitudes at P¯Singh1, Erni2, Krusche3 et al. 2017Phys. Rev. D411250View full textAdd to dashboardCite

“…However, very significant results on the electromagnetic form factors in the timelike region using the pp → e þ e − reaction were obtained by the E835 experiment at Fermilab National Accelerator Laboratory (FNAL) [8]. But inclusive lepton pair production and hard exclusive channels still remain unexplored.…”

Polarisation observables in lepton-antilepton-to-proton-antiproton reactions including lepton mass

“…Experimental values for the proton have been obtained over the last 50 years via electron proton scattering, often using the Rosenbluth separation technique [1]. The magnetic proton form factor, which is the dominant term in elastic ep scattering, has been measured at q 2 values up to 31 GeV 2 in the space like region [2] and fromp p or e − e + annihilation up to q 2 = 5.6 GeV 2 [3]. They show that the magnetic form factor, G M , follows approximately a dipole form G D = 1 + q 2 /0.71 (GeV 2 ) −2 , where q 2 is the four momentum transfer squared.…”

Feasibility studies of time-like proton electromagnetic form factors at $\overline{\rm P}$ P ¯ ANDA at FAIR

“…BaBar data [32,33] suggest a steeper decrease with s, and show a strong energy dependence near threshold [34]. [35,36], Fenice [37], PS170 [12], E760 [38], DM1 [39], DM2 [40,41], BES [42], BESIII [14], CLEO [43], BaBar [32,33]. Different parameterizations are shown based on eq.…”