D. P. Watts

Photoproduction of eta-mesic He-3

The photoproduction of eta-mesic 3He has been investigated using the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI. The total inclusive cross section for the reaction gamma3He-->etaX has been measured for photon energies from threshold to 820 MeV. The total and angular differential coherent eta cross sections have been extracted up to energies of 745 MeV. A resonancelike structure just above the eta production threshold with an isotropic angular distribution suggests the existence of a resonant quasibound state. This is supported by studies of a competing decay channel of such a quasibound eta-mesic nucleus into pi(0)pX. A binding energy of (-4.4+/-4.2) MeV and a width of (25.6+/-6.1) MeV is deduced for the quasibound eta-mesic state in 3He.

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.

The reaction gamma p ->pi(0)gamma ' p and the magnetic dipole moment of the Delta(+)(1232) resonance

The reaction

Photoproduction of πmesons from nuclei

\gamma p \to \pi^\circ \gamma^\prime p

Double pi 0 photoproduction off the proton at threshold

has been measured with the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for energies between

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

\sqrt{s}

Near-threshold measurement of the He-4(gamma,n) reaction

= 1221--1331 MeV. Cross sections differential in angle and energy have been determined for all particles in the final state in three bins of the excitation energy. This reaction channel provides access to the magnetic dipole moment of the

C(,pn) photon asymmetry for Eγ=180–340 MeV

\Delta^{+}(1232)

Evaluation of resistive-plate-chamber-based TOF-PET applied to in-beam particle therapy monitoring

resonance and, for the first time, a value of

Three-nucleon mechanisms in photoreactions

\mu_{\Delta^+} = (2.7_{-1.3}^{+1.0}(stat.) \pm 1.5 (syst.) \pm 3(theo.)) \mu_N