Visit to CALICE ECAL testbeam (by Shinshu)

at DESY, 16th – 19th October 2012

Samir Arfaoui &Erik van der Kraaij

30th October 2012

Setup @ DESY

30th October 2012Erik van der Kraaij, CERN LCD 2

Scintllators: • 45x5x2mm strips are used by the japanese• they recycled them from a previous prototype tile

and had the strips cut from it• no clear supplier for their scintillators

Read-out:• Hammamatsu MPPC (model?)• Their layer has 144 tiles (36x4) with

4 HBU and 4 SPIROC2b chips. • On top, 3 cards: 

– DIF (LEMO for Spill signal, TTL signal, and Reset)

– Calibration board (LED)– Data-out board with USB connector

Setup @ DESY

30th October 2012Erik van der Kraaij, CERN LCD 3

Trigger• Self-trigger: when one tile has a hit over threshold, all the

tiles on the same HBU (36 total) are read out.• Validation mode: a crossed scintillator pair in coincidence for

external trigger, upstream of the prototype. If validation signal is sent within clock-cycle of self-trigger, data is flagged as validated– Helpful to get rid of noise self-triggers– Japanese team did not manage to operate in this mode

Front-end: SPIROC2b • Seems to be a black box…• Memory: 16 events and 0.5-1s for read-out• Complex configuration (Labview programs by DESY people)

not a good idea for early CERN lab setup…• Need expertise (LAL? DESY?) for initial setup/operation

– Japanese team lacked it, slowed them down greatly

Setup @ DESY

30th October 2012Erik van der Kraaij, CERN LCD 4

Came in this morning from Katsu• They managed to perform measurements at various positions in

the shower

Setup @ CERN

30th October 2012Erik van der Kraaij, CERN LCD 5

Need for CERN lab:• at least 3 scintillators: 2 for coincidence trigger to get rid of

the noise and the one under test• collimated radioactive source• SiPM + decoupling circuit => Picoscope• Hamamatsu MPPCs from DESY (thank you)

– 10 of them in Samir’s office (+ a couple of reflective foil sheets)

• Black box with cooling (or at last temperature monitoring) and shielding

Readout options (from Christian)• EasiRoc. High level of integration. 128+ channels. ADC, no

TDC. Could be made available by Aachen.• SPIROC + testboard at OMEGA. Details still to clarify.• CAEN VME module (similar to Erika @ DESY). PreAmp, ADC,

TDC. How to bias MPPCs? CERN pool?• Picoscope. 4 channels. Bias via Keithley. CERN pool?

More pictures on the strips

30th October 2012Erik van der Kraaij, CERN LCD 6

TeraScale Alliance testbox

• For single channel

30th October 2012Erik van der Kraaij, CERN LCD 7

Decoupling

• Multi-channel board

30th October 2012Erik van der Kraaij, CERN LCD 8

Readout by VME

• Instead of picoscopes

30th October 2012Erik van der Kraaij, CERN LCD 9

Readout by VME

• …

30th October 2012Erik van der Kraaij, CERN LCD 10