Contribution to a conference proceedings

PUBDB-2014-04554

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Calibration of Olympus/Doris Beam Position Monitors

Schneekloth, U. (Corresponding Author)DESY* ; Goerrissen, N.Extern* ; Kube, G.DESY* ; Neugebauer, J.DESY* ; Neumann, R.DESY* ; Schmidt-Foehre, F.DESY*

2014

Abstract: The goal of the OLYMPUS experiment is a precise measurement of the ratio of the positron-proton and electron- proton elastic scattering cross sections in order to quantify the effect of two-photon exchange. The experiment was performed using intense beams of electrons and positrons stored in the DORIS ring at Deutsches Elektronen Synchrotron in Hamburg, impinging on an unpolarized, internal, hydrogen gas target. An essential ingredient of the experiment is a precise determination of the luminosity, which requires a precise knowledge of the beam position of both beam species. During DORIS operation cylindrical button beam position monitors, read out by two independent electronics systems, were mounted up- and down- stream of the target chamber. After the end of operation, the readout systems were cross-calibrated. The BPMs were then calibrated using a test-stand, consisting of a wire scanner assembly. The beam was simulated by applying an RF signal to the wire. This paper describes the calibration principles and test setup, together with the results compared to the expected BPM response.

Note: OA

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Contributing Institute(s):

1. OLYMPUS Kollaboration (OLYMP)

Research Program(s):

1. Experiments at DORIS (OLYMPUS) (POF2-515) (POF2-515)

Experiment(s):

1. DORIS: OLYMPUS

Appears in the scientific report 2014

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Database coverage:

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