The OLYMPUS Experiment
Abstract
The OLYMPUS experiment was designed to measure the ratio between the positron-proton and electron-proton elastic scattering cross sections, with the goal of determining the contribution of two-photon exchange to the elastic cross section. Two-photon exchange might resolve the discrepancy between measurements of the proton form factor ratio, , made using polarization techniques and those made in unpolarized experiments. OLYMPUS operated on the DORIS storage ring at DESY, alternating between 2.01~GeV electron and positron beams incident on an internal hydrogen gas target. The experiment used a toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight detectors to measure rates for elastic scattering over the polar angular range of approximately --. Symmetric M{\o}ller/Bhabha calorimeters at and telescopes of GEM and MWPC detectors at served as luminosity monitors. A total luminosity of approximately 4.5~fb was collected over two running periods in 2012. This paper provides details on the accelerator, target, detectors, and operation of the experiment.
Cite
@article{arxiv.1312.1730,
title = {The OLYMPUS Experiment},
author = {R. Milner and D. K. Hasell and M. Kohl and U. Schneekloth and N. Akopov and R. Alarcon and V. A. Andreev and O. Ates and A. Avetisyan and D. Bayadilov and R. Beck and S. Belostotski and J. C. Bernauer and J. Bessuille and F. Brinker and B. Buck and J. R. Calarco and V. Carassiti and E. Cisbani and G. Ciullo and M. Contalbrigo and N. D'Ascenzo and R. De Leo and J. Diefenbach and T. W. Donnelly and K. Dow and G. Elbakian and D. Eversheim and S. Frullani and Ch. Funke and G. Gavrilov and B. Gläser and N. Görrissen and J. Hauschildt and B. S. Henderson and Ph. Hoffmeister and Y. Holler and L. D. Ice and A. Izotov and R. Kaiser and G. Karyan and J. Kelsey and D. Khaneft and P. Klassen and A. Kiselev and A. Krivshich and I. Lehmann and P. Lenisa and D. Lenz and S. Lumsden and Y. Ma and F. Maas and H. Marukyan and O. Miklukho and A. Movsisyan and M. Murray and Y. Naryshkin and C. O'Connor and R. Perez Benito and R. Perrino and R. P. Redwine and D. Rodríguez Piñeiro and G. Rosner and R. L. Russell and A. Schmidt and B. Seitz and M. Statera and A. Thiel and H. Vardanyan and D. Veretennikov and C. Vidal and A. Winnebeck and V. Yeganov},
journal= {arXiv preprint arXiv:1312.1730},
year = {2014}
}
Comments
40 pages, 26 figures