Search results for "Electron Scattering"

Parity Violating Electron Scattering at the MAMI Facility in Mainz

2005

We report here on a new measurement of the parity violating (PV) asymmetry in the scattering of polarized electrons on unpolarized protons performed with the setup of the A4-collaboration at the MAMI accelerator facility in Mainz. This experiment is the first to use counting techniques in a parity violation experiment. The kinematics of the experiment is complementary to the earlier measurements of the SAMPLE collaboration at the MIT Bates accelerator and the HAPPEX collaboration at Jefferson Lab. After discussing the experimental context of the experiments, the setup at MAMI and preliminary results are presented.

The Super-FRS Project at GSI

2002

The GSI projectile fragment separator FRS has demonstrated with many pioneering experiments the research potential of in-flight separators at relativistic energies. Although the present facility has contributed much to the progress in the field of nuclear structure physics, major improvements are desirable in the future. The characteristics of the proposed next-generation facility at GSI, the Super-FRS, will be presented and compared to other projects. The Super-FRS is a large-acceptance superconducting fragment separator followed by different experimental branches including a combination with a new storage-cooler ring system. This system consists of a collector ring (CR) and a new experime…

A highly polarized target for the electron beam at MAMI

2009

Abstract Polarized He 3 from metastability exchange optical pumping (MEOP) is used as an effective polarized neutron target for electron scattering experiments at the MAinz MIcrotron (MAMI). With the present setup an initial polarization of up to 72% has been obtained at the experimental area. A novel calibration technique will be presented which allows the determination of the absolute polarization within a relative uncertainty of 3%.

Parity-violating electron scattering at MAMI

2003

A measurement of the parity-violating asymmetry in elastic scattering of polarized electrons on protons is currently running within the A4 Collaboration at the MAMI facility in Mainz. The aim is to reveal the contribution of strange quarks to the form factors of the nucleon at a Q 2 = 0.23 GeV2. The expected asymmetry without strangeness is around 5.4 × 10−6. After 600 hours of asymmetry data taking, an accuracy of 1 × 10−6 has been achieved.

Electron Scattering Experiments at the Mainz 300 MeV Linear Accelerator

1970

The Mainz electron scattering facility provides energies between 80 and 300 MeV and scattering angles up to 158° which corres-pond to a useful momentum transfer region 0.4 ≤ q ≤ 3.0 fm−1. The accelerator and analyzing system produce approximately 1 μA average current with the overall resolution in the final spectra of usually 0.15% to 0.30%.

Physics at the electron accelerator MAMI

1995

Abstract An overview of physics at the Mainz Microtron facility MAMI is given. After a short description of the essential parameters of the accelerator, selected results of three different collaborations A1, A2, and A3, each centered around one major experimental facility, are presented. The A1 collaboration has installed a setup of three large acceptance magnetic spectrometers. Results presented are high momentum components (pm ≤ 700MeV/c) in 16O(e, e′p), L T separation and LT interference structure functions in p(e, e′π+), and angular distribution of p(e, e′p)π0 at π0 threshold. The A2 collaboration has installed a broad band tagger for experiments with nonpolarized and polarized photons.…

Recent results from experiments at MAMI

2012

Abstract The Mainz Microtron MAMI is an ideal tool for studying the structure of strongly interacting systems with an electromagnetic probe. With the new HDSM accelerator stage of MAMI C, a continuous-wave electron beam with an energy of up to 1604 MeV and excellent beam quality is available for precision experiments. In addition, polarisation degrees of freedom can be exploited with polarised beams and either polarised targets or recoil polarimetry. This paper presents selected results of the A1, A2, and A4 collaborations.

Comment on “Comparison of Polarization Observables in Electron Scattering from the Proton and Deuteron”

1998

Die elektronenstreu-apparatur am mainzer 300 MeV-elektronen-linearbeschleuniger

1972

Abstract In this paper, we attempt to give a general survey and a comprehensive description of the most significant features of the facilities for electron scattering experiments at the Mainz 300 MeV Linear Accelerator, along with a list of literature, where more detailed information on certain subjects can be found. The accelerator provides energies between 80 and 300 MeV. Scattering angles are available up to 160° resulting in a momentum transfer region up to 3.0 fm −1 . The overall experimental resolution is 0.1%. Cross sections down to 10 −34 cm 2 /sr can be measured. The main features of the apparatus are: an achromatic magnet system with 90° deflection, a double focusing spectrometer,…

Neutral currents in atomic and nuclear physics

1990

Abstract The spin structure function of the proton measured by the EMC collaboration suggests an axial isoscalar neutral current for the nucleon. I study its implications for neutral current phenomena in atomic and nuclear physics. This includes parity-violating observables for transitions between hyperfine multiplets in light muonic atoms, selected inelastic neutrino nuclear reactions and the polarization asymmetry in electron scattering for isoscalar transitions. The neutrino-induced process 7 Li → 7 Li ∗ (0.478 MeV ) is particularly favourable for neutrino reactor experiments. I find that the axial isoscalar coupling extracted from the EMC measurement increases the neutrino cross section…