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 2004-2005

DC

gas

Bag

gas

Sbag2

Sbag1

Vbubbler bubbler

pbagpDC

XR

XL

YO

XL,XRYO ,XR +XL

Pbag ,PDC Pbag -PDC

Hood foil stability test a) .1 mm not reached at flux changes

b) V-bubbler successful

c) XR,XL,YO 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=6m) 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 procedureOnly minor modifications to the previously designed tools

DC report june_04,J.E.

Stesalit

11

0 m

m

199 mm 331 mm

basis

wings

Carbon fibers

Frame shapea) 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 resolutionbuild 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 intensitiesSince 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.

2002 2003 2004 2005

Test MilestoneAssemblyDesign Manufacturing

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 insideCOBRA

Inside COBRA

Full Size Prototype

Mod tools

2004 2005

Test MilestoneAssemblyDesign Manufacturing

Drift Chamber

outside insideCOBRA

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

1 29 30

30

1

Other Prints 1

Print anode 1

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

2004J F M A M J J A S O N D

Beam Time MEG

Pra

c MEG Gotta

COBRACalibration

(Wed)

Beam

Line

Commiss.

Part 1

Pla

tf.

Drift

Chamber

Proto

type

Timing Counter TestMechan.

Matching

LPTNeutr.

BGPM + Src Inst

Pi- Beam

Test

Liq.

Purif.

Full Calorimeter

Trigger

DAQ

Te

st

2005 2006J F M A M J J A S O N D J F M A

Beam Time Shutdown MEG Gotta? MEG Shutdown

COBRAField

MapBeam

Line

BTS

Test

Commiss.

Part 2

Full Beam

Line Test

Drift

ChamberMounting

Mounting &

Testing

Timing

Counter

BG

Test

BG

TestInst

LPT PMT testing + calibration

Full

Calorimeter

Cryo.

Installation

Crane+

TentAssembly

Studies

(Wed + remote)Test

Trigger

Inst Inst

DAQDC

Electr.

Inst Inst