P. Bartsch

Precise neutron magnetic form factors

Precise data on the neutron magnetic form factor Gmn have been obtained with measurements of the ratio of cross sections of D(e, en) and D(e, ep) up to momentum transfers of Q 2 = 0.9 (GeV/c) 2 . Data with typical uncertainties of 1.5% are presented. These data allow for the first time to extract a precise value of the magnetic radius of the neutron.  2002 Elsevier

Measurement of the electric form factor of the neutron at Q 2 = 0.3-0.8 (GeV/ c) 2 ⋆

Abstract.The electric form factor of the neutron, GE,n, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(¯e, e’¯n)p reaction. Three data points have been extracted at squared four-momentum transfers Q2 = 0.3, 0.6 and 0.8 (GeV/c)2. Corrections for nuclear binding effects have been applied.

Polarization transfer in the 4He(e→, e′ p→)3H reaction

We have measured the proton recoil polarization in the {sup 4}He(polarized-e, e-prime, p){sup 3}H reaction at Q{sup 2} = 0.5, 1.0, 1.6, and 2.6 (GeV/c){sup 2}. The measured ratio of polarization transfer coefficients differs from a fully relativistic calculation, favoring the inclusion of a predicted medium modification of the proton form factors based on a quark-meson coupling model. In contrast, the measured induced polarizations agree reasonably well with the fully relativistic calculation indicating that the treatment of final-state interactions is under control.

First determination of generalized polarizabilities of the proton by a virtual compton scattering experiment.

Absolute differential cross sections for the reaction (e+p ->e+p+gamma) have been measured at a four-momentum transfer with virtuality Q^2=0.33 GeV^2 and polarization \epsilon = 0.62 in the range 33.6 to 111.5 MeV/c for the momentum of the outgoing photon in the photon-proton center of mass frame. The experiment has been performed with the high resolution spectrometers at the Mainz Microtron MAMI. From the photon angular distributions, two structure functions which are a linear combination of the generalized polarizabilities have been determined for the first time.

Measurement of the electric form factor of the neutron at Q2 = 0.3-0.8 (GeV/ c) 2⋆

Abstract.The electric form factor of the neutron, GE,n, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(¯e, e’¯n)p reaction. Three data points have been extracted at squared four-momentum transfers Q2 = 0.3, 0.6 and 0.8 (GeV/c)2. Corrections for nuclear binding effects have been applied.

High-precision studies of the 3He(e,e'p) reaction at the quasielastic peak

Precision studies of the reaction

Polarization transfer in the 4HeH reaction

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The horizontal drift chambers for the focal plane proton-polarimeter of the 3-spectrometer setup at MAMI

He(e,e

Self energies of the pion and the Δ isobar from the 3He(e, e'π+)3H reaction

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Polarization transfer in the

p) using the three-spectrometer facility at the Mainz microtron MAMI are presented. All data are for quasielastic kinematics at