An Idea of Next Sci-ECAL Prototypefor FNAL Beamtest

Feb-7 2008 Sci-ECAL meetingS. Uozumi (Kobe)

Tungsten absorber assembly

Steel frame(3.54+3+1 mm thick)

Thickness of thispart should be 3 mm

(for readout andmonitoring system)

Tungstenplate

1 2

3 4

White acrylicFrame

(3 mm thick)

Guide railsfit for shelf

(not necessary?)

18 cm

20 cm

One complete layer

flat cable with MPPCs(9 channels)

Acrylic barFor gain monitoring

Length of the flat cable• Not easy to decide, because …– Space to put our detector is limited.– Just behind the Sci-ECAL, AHCAL will be located.– Readout electronics takes some space. (size of 1 board ~ 95.3 x 19 cm, we will use ~23 boards.– Need to know available space for our detector in front of

the AHCAL. Ask Erika or someone at DESY ?– Make a touch panel to hook up signal lines? It can change the connector bundle size at the same time, if

necessary.

AHCAL

Beam

Readout electronics channels• Each flat cable has 9 channel connector.• Readout baseboard has 14, 30 or 32 ch connectors.• If we connect them directly (as done in the DESY BT), there

will be some unused channels. (just 90 channels out of 108 are used.)• At the FNAL BT, we will have 23 (+2) baseboards.• If we use 90 ch per a board, total available num. of readout

channels will be 2070.• On the other hand, total detector channels will be

– 72 strips x 30 layers = 2160 ch– 32 layers = 2304 ch

• For case of 30 layers, 24 baseboards will be enough.• For 32 layers case, we have to use electronics more

efficiently. (In this case converting 9 ch connector to 6 channel bundle will be useful.)

Things to concern / discuss …• Number of layers ?– How much is the shower leakage with 30 / 32 layers ?– By the way, how many tungsten plates in Shinshu ?

• Design and cabling of gain montoring system– Also need to have available space

• Shelf for cal layers / electronics / CMBs– Is the guide rail necessary for the cal layers?– Available space – this also defines the length of flat cable.

• Is it really possible to make the designed structures?– Ability of machining, mechanical / dynamical issue, machining precision– Need to consult with machining company.– Detailed structure will be modified in that discussion.