# 54. International Winter Meeting on Nuclear Physics

25-29 January 2016
Bormio, Italy
Europe/Berlin timezone

## Measurement of the beam normal single-spin asymmetry of Carbon-12

27 Jan 2016, 18:25
20m
Bormio, Italy

#### Bormio, Italy

Short Contribution Nuclear Structure and Astrophysics

### Speaker

Dr Anselm Esser (Inst. f. Kernphysik / Uni Mainz)

### Description

Beam-normal single-spin asymmetry in the elastic scattering of electrons is a direct probe for the two photon exchange. At the Mainz Mictrotron, this asymmetry has been measured for Carbon-12 at a Q² of 0.04 GeV². A 570 MeV continuous wave electrons beam was scattered on a carbon target and detected by two magnetic spectrometers. Quartz glass cherenkov detectors located at the elastic line in the spectrometer's focal plane were used to measure the amount of scattered electrons. The PMTs of which were read out with integrating current ADCs allowing for particle rates too high for counting. The resulting asymmetry shows a surprising deviation from theoretical predictions.

### Primary author

Dr Anselm Esser (Inst. f. Kernphysik / Uni Mainz)

 Slides