Internal Target Experiment at DORIS

1. Richard Milner April 22, 2008

2. Internal Target Experiment at DORIS Young-Kee Kim, on behalf of PRC PRC64 Meeting: Findings / Recommendations DESY Extended Scientific Council Meeting, November 19-20 • Proposal of a new experiment at DORIS using the available MIT-BLAST detector and an unpolarized hydrogen gas target. • The goal is to determine the contribution of multiple photon exchange processes and to resolve the existing discrepancy in lepton-nucleon scattering data. Dedicated data taking for one month per year for several years would be sufficient. • External referees to review. They strongly support the physics case. The PRC recommends DESY management discuss with the accelerator group. Discrepancy Detector & Target Exist Richard Milner April 22, 2008

3. BLAST@DORIS pOsitron-proton and eLectron-proton elastic scattering to test the hYpothesis of Multi- Photon exchange Using DoriS OLYMPUS Hera ZEUS Hermes Richard Milner April 22, 2008

4. Update at PRC No `showstoppers’ in running DORIS accelerator for OLYMPUS OLYMPUS installation and commissioning in parallel with DORIS light source operation Physics case viewed favorably by DOE Meeting of interested physicists March 31st at DESY More than 30 physicists from 10 institutions in Germany, Italy, Russia, U.K., U.S. Representation from leading German hadron physics university groups: Bonn, Erlangen, Mainz Working to prepare a detailed proposal with a formal collaboration by the end of summer 2008 Window of ~ 3 years (~2009-2012) opening up for many groups Formal encouragement by DESY requested Next collaboration meeting planned for ~ June at DESY Richard Milner April 22, 2008

5. After PRC meeting… • Naohito Saito appointed referee to PRC • I had a meeting with Rolf Heuer, Naohito Saito, and Joachim Mnich after the PRC meeting • RH encouraged discussion of an aggressive schedule where BLAST would be shipped in calendar year 2009. Also in the proposal we should discuss a more aggressive schedule to carry out the experiment. Different schedules should be considered. • Need to clarify collaboration size and funding sources, financial request of DESY • RM asked to give talk to DESY Extended Scientific Council on May 26th • Proposal to be ready by the end of summer 2008 Richard Milner April 22, 2008

6. Richard Milner April 22, 2008

7. Building OLYMPUS collaborationand funding for experiment • I have been in contact with Klaus Rith, chairman of the German hadronic funding committee. They will meet in early June and Klaus has requested a list of items which would be requested by the German hadron physics groups • Dietrich von Harrach has sent me a starting draft list of items which would be funded by the German groups Richard Milner April 22, 2008

8. Building OLYMPUS collaborationand funding for experiment (contd.) • I have also been in discussion with Italian groups: Ferrara, Frascati, Rome. They are strongly interested but constrained in terms of capital equipment costs by existing commitments to HERMES and JLab • I have sent the DESY letter to John Arrington and Roy Holt at ANL and encouraged them to become actively involved. • The St. Petersburg group (Stan Belostotski) are very interested to participate. Richard Milner April 22, 2008

9. Action Items • Need to determine cost and schedule to disassemble, ship, reassemble BLAST toroid and detectors. Presumably this will be the basis of a request to DOE later this year. • Note that it will be very advantageous to have European groups to come visit Bates before disassembly. • Need to identify groups to share responsibility for various aspects of the experiment • Need to form active group on OLYMPUS simulations • Need to determine the date of the next OLYMPUS meeting at DESY. Goal will be to form collaboration with clearly identified responsibilities. Richard Milner April 22, 2008