1. 1 Referee Report Olympus Elke Aschenauer Desy PRC, April 2011

2. Congratulation to the collaboration for a great progress since the last PRC meeting basically all detectors are at DESY (GEMs not yet) first test beams have been done next test beam planned in May GEM-lumi, MWPCs, Symmetric Moeller calo GEM tracker would be nice to have for redundancy in tracking, but not critical Toroid was powered and field was measured. Test-Run in February 2011 DORIS has been run successfully with both charges luminosities as required in the TDR Rates in detectors looked reasonable  saw protons from ep-elastic target worked fine, but had problems with higher order mode heating target-chamber/cell under revision should be tested as soon as possible again with beam Desy PRC, April 2011 2

3. Till the next PRC meeting: important milestones: test beam in May assemble detector till July role detector into DORIS; use DORIS service weeks for studies Offline analysis should be continued to be pushed fast offline analysis critical for quality of measured data One concern possible delay of the 2 nd beam-time in 2012 due to delay in PETRA shutdown (3-6 month) should be avoided Congratulation and Looking forward Congratulation and Looking forward to hearing about more success ! to hearing about more success ! Desy PRC, April 2011 3