Abstract
The A2 Collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to energies of 1.6 GeV. The photons are produced in the ‘Bremsstrahlungs’ process, the energy is determined by a dedicated tagging system. The Crystal Ball-TAPS detector system with its high capability to cope with multi photon final states is used to acquire data with a variety of nonpolarized and spin polarized targets. Physical goals are the investigation of the nucleons excitation spectrum via single and double meson photoproduction and in addition a detailed determination of meson decays in precision experiments. We have started a program to measure double polarised Compton scattering to determine the nucleons scalar and spin polarisibilities. In this proceedings recent results from A2 collaboration
Highlights
The A2 Collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to energies of 1.6 GeV
The beam is derived from the production of Bremsstrahlung photons during the passage of the MAMI electron beam through a thin radiator
The Crystal Ball detector (CB) is a highly segmented 672-element NaI(Tl), self triggering photon spectrometer constructed at SLAC in the 1970’s
Summary
The MAMI accelerator with its source of polarised electrons, based on the photoeffect on a strained GaAs crystal, routinely delivers polarised beam with a maximum energy of 1604 MeV and a degree of polarisation of approximately 85%. The last accelerator stage, MAMI C, is realized as a Harmonic Double Sided Microtron (HDSM). The A2-Glasgow-Mainz tagging facility [2] stands out due to its high photon intensity. The beam is derived from the production of Bremsstrahlung photons during the passage of the MAMI electron beam through a thin radiator. The resulting photons can be circularly polarised, with the application of a polarised electron beam, or linearly polarised, in the case of a crystalline radiator. Photons can be tagged in the momentum range from 4.7 to 93.0% of E0
Sign-in/Register to view highlights & summary 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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
