1. Malte HildebrandtMEG Review Meeting, 14th February 2007 Report of Run Coordinator Run 2006 Summary Malte Hildebrandt MEG Review Meeting, 14th February 2007

2. Malte HildebrandtMEG Review Meeting, 14th February 2007 Pre-Commissioning Run 2006 beam and detector operation:16 th – 22 nd December 2006 (continuously around-the-clock) goals: run pressure control system to flush COBRA and dc find beam settings for very low, low and high beam rate start operation and data taking with dc and tc perform neutron background measurement take data with NaJ and plastic scintillator realisation: daily run meeting summarise past 24 h collect requests, wishes, requirements organise upcoming 24 h daily run plan for an efficient usage and sharing of the rare beam time:

3. Malte HildebrandtMEG Review Meeting, 14th February 2007 Beam Line First measurement of muon beam rate in center of COBRA with complete set of beam line elements, in particular with: degrader correction coils on BTS degraderbeam transport solenoid (BTS)correction coils for BTS

4. Malte HildebrandtMEG Review Meeting, 14th February 2007 COBRA, End-Caps and Insertion System COBRA field stability ~0.05 % (FWHM) 2 quenches: reasons not completely understood nevertheless:quick recovery (< 3 h) due to newly installed turbo molecular pump End-Caps both end-caps installed insertion system installed and operated successfully upstream end-cap downstream end-cap with insertion system

5. Malte HildebrandtMEG Review Meeting, 14th February 2007 Gas Distribution and Supply He volume inside COBRA improved He distribution system inside both end-caps and along dc cable duct → He fraction >95 % after a few hours Drift Chamber PSI safety requirements fullfilled to operate with 10 l bottle C 2 H 6 stainless steel tubingoxygen sensor ethane sensor downstream end-cap

6. Malte HildebrandtMEG Review Meeting, 14th February 2007 „MEG“-target in parking position „MEG“-target in measuring position phase 2:„MEG“-target in measuring position Target phase 1: during beam commissioning „APD“-target („MEG“-target parked) Target „APD“-target

7. Malte HildebrandtMEG Review Meeting, 14th February 2007 Drift Chamber installation: 8 dc modules (8 out of 16) gas manifolds (us and ds) pressure gauges gas tubing 7 (out of 2*8) planes operational problems: leaks, HV, LV?,... tasks:HV conditioning without beam HV conditioning with beam I anode = I anode (beam rate) data taking: R anode = R anode (r-coordinate) waveform analysis, tracking... dc04 dc05 dc06 dc07 dc08 dc09 dc11 dc10 flange to BTS dc support gas manifold us differential pressure gauge gas manifold ds and gas tubing „MEG“ target

8. Malte HildebrandtMEG Review Meeting, 14th February 2007 Pressure Control System Pressure control system worked stable and reliable! inlet gas manifold oulet gas manifold -1.2 10:00 11:00 time [h] P DC – P COBRA [Pa] drift chamber

9. Malte HildebrandtMEG Review Meeting, 14th February 2007 Timing Counter installation: nitrogen bags (us and ds) N 2 distribution system all tc bars: 15 tc bars us 15 tc bars ds no tc fibres tasks:gain calibration cosmics with / without B rate tc us vs tc ds data taking: waveform analysis charge ratio studies event distribution... N 2 bag us end-cap flange to BTS copper collar to seal N 2 bag vs end-cap PMT of tc bars N 2 flushing tubes

10. Malte HildebrandtMEG Review Meeting, 14th February 2007 Supplementary Components NaJ and plastic scintillator tasks:studies of radiative muon decay background studies for later LXe Bonner Sphere System and 3 He detector tasks:neutron background measurement with final beam line elements and final beam settings →previous measurements confirmed →no concerns about neutron background in LXe calorimeter

11. Malte HildebrandtMEG Review Meeting, 14th February 2007 Trigger, DAQ, Logging and Central MIDAS Trigger36 Type 1 boards 5 Type 2 boards 4 Ancillary boards all cabling Firmware version 0 DAQDRS chips + cables for: DC:864 channels TC: 60 channels NaJ: 9 channels Logging and Central MIDAS installed and operational (except for dc_trigger) data taking with all channels of installed sub-detector components

12. Malte HildebrandtMEG Review Meeting, 14th February 2007 Beam Tuning and Data Taking data taking all channels of installed sub-detector components recorded 285 runs taken at different beam rates and HV settings → in total ~600 GB recorded MEG Review Meeting February 2007: not only technical talks but also talks about analysis of „real“ data beam tuning settings for very low beam rate 3 % low beam rate25 % high beam rate 100 % of ≥ 6 · 10 7   / s at center of COBRA I proton = 1.8 mA 6 cm target E