1. JRA3 Eurotag report, Oct 20061 Eurotag Development of the European tagged photon facilities. Spokesperson: Ken Livingston, Glasgow Members: Glasgow, Bonn, Giessen, INFN, Lund, Mainz, Tuebingen, Kharkov, JLab Award: 600k Project Status: ManpowerAll EU funded posts are now filled: 7 postdocs for > 11 man years Workshop A 2 day workshop to be held early 2007. Timelines On target ( averaged over 6 sub-projects ) DisseminationWeb site: www.nuclear.gla.ac.uk/~kl/Eurotag …. needs updating. Internal reports, conference proceedings

2. JRA3 Eurotag report, Oct 20062 Prototype tagger electronics (J. Annand, Glasgow) PMT Voltage divider x10 amplifier Dual threshold discriminator Coincidence logic PECL Outputs for Catch standard. Prototyped by Glasgow (J. Annand) and Zott Ltd (Edinburgh) Prototype completed in spring 2006 400 boards made by Zott. Currently being installed Upgraded Glasgow Tagger in Mainz

3. JRA3 Eurotag report, Oct 20063 Polarimetry 1. Coherent Bremsstrahlung Calculation (Tuebingen) Used successfully, needs only photon tagger Many free parameters, > 5% systematic error Developments by Glasgow and Tuebingen Papers in preparation (D.Glazier, P. Grabmayr) 2. Use reaction with a known photon asymmetry (Mainz) Can be high statistics Very good relative monitor of polarization Non-indpendent – depends on specific expt Need very good systematics or calibration Investigation by Mainz (R. Beck et al.)

4. JRA3 Eurotag report, Oct 20064 3. Build a prototype polarimeter (Bonn, Kharkov, Glasgow, Jlab) Kharkov Monte carlo simulations of Pair and Triplet polarimetry solutions (with Bonn) JlabRecent results and analysis of polarimeter for g8b (see below) PRELIMINARY J.Santoro, CUA Asymmetry from Si Microstrip detectors. Average over full Photon energy range Peak > 90% pol. Aim: Build a prototype polarimeter based on simulations and experience from JLab. Small, portable, in-beam, fast (ie better than 5% in order of minutes) K.Livingston, Glasgow Polarimetry