MEG DC (report June 04) DC report june_04,J.E. a)Foil stability and quench related problems b)How to get more stability c)Frame design d)Measurement of the  target position e)schedule

DC gas Bag gas Sbag2 Sbag1 Vbubbler bubbler p bag p DC XRXR XLXL YOYO XL,XRXL,XR Y O,X R +X L P bag,P DC P bag -P DC Hood foil stability test a).1 mm not reached at flux changes b) V-bubbler successful c) X R,X L,Y O correlated  Larger forces on the foil  „vertical forces“, stabilize chamber width DC report june_04,J.E.

a)Larger forces on the frame  larger deformations b)How to get „vertical forces“ Control of the HV to avoid damages during quench a)Quench is relatively slow :  > > 1 sec b)To fast switch off (chamber HV) is also dangerous : RC(chamber) ~ 10  s c)  switch off time ~ 100  s We think about ways to test the behavior to quenches, as soon as the Al-frame full size prototype will be completely available DC report june_04,J.E.

Mounting of Cathode foils c) Cut foil  vertical miniforce on the foil Also z-stability better (^  expansion coef  b) Position (.1 mm) stretched foils and glue them on frame and ROHACELL DC report june_04,J.E. a) Stretched carbon fibers(1000x d=6  m) and deformed ROHACELL Pretension forces on frame to simulate carbon fibers and foils, glue fibers

Mounting of Hood foil Largest height Not disturbing the cell To do better: Stretch „vertically“ and fix the width a)Modify the shape of the hood to have a larger flat surface to glue b)Machine a foam structure in ROHACELL 30 c)Adapt the cathode foil procedure Only minor modifications to the previously designed tools DC report june_04,J.E.

Stesalit 110 mm 199 mm331 mm basis wings Carbon fibers Frame shape a)fix dimensions of foils  order b)Only wing print + built in LV supply cable c)carbon fibers solution (  ) and price d) modify frame shape to correct in first order for: basis shape ( first cell) frame height (foil height) edge angle (gluing) tested DC report june_04,J.E.

 target position a)Without knowing the exact spectrometer resolution build a target with holes of different sizes b)Knowing the exact spectrometer resolution optimize the size of a series of holes and slits on the target to clearly see the holes without loosing too much intensities Since the non stopped  seem to have a larger probability to contribute to the background, the edge of the target will not be sharp enough. DC report june_04,J.E.

Test Milestone AssemblyDesignManufacturing Full Prototype Medium PrototypeCharge division & Cosmics Full Detector (18 DC) Drift Chamber Full Prototype Beam test Full Prototype Charge division & Cosmics Medium Prototype Full Detector (18 DC) outside inside COBRA Inside COBRA Full Size Prototype

Mod tools Test Milestone AssemblyDesignManufacturing Drift Chamber outsideinside COBRA Inside COBRA Feb Mar Apr Mai Jun jul Aug Sep Oct Nov Dec Jan Feb Mar Apr Mai Jun Jul Aug Order Delivery Foil frames tests Other Prints1 Print anode1 Simul,design Preamp cable Full Size Prototype,Al Tests anode Full prototype Full Detector (18 DC) Beam,quench support Inside COBRA calibration DC report june_04,J.E. cosmics beam

2004 JFMAMJJASOND Beam Time MEG Prac MEGGotta COBRA Calibration (Wed) Beam Line Commiss. Part 1 Platf. Drift Chamber Proto type Timing Counter Test Mechan. Matching LPT Neutr. BG PM + Src Inst Pi- Beam Test Liq. Purif. Full Calorimeter Trigger DAQ Test

JFMAMJJASONDJFMA Beam Time ShutdownMEGGotta?MEG Shutdown COBRA Field Map Beam Line BTS Test Commiss. Part 2 Full Beam Line Test Drift Chamber Mounting Mounting & Testing Timing Counter BG Test BG Test Inst LPT PMT testing + calibration Full Calorimeter Cryo. Installation Crane+ Tent Assembly Studies (Wed + remote) Test Trigger Inst DAQ DC Electr. Inst