Development of the CpFM at INFN Rome Test BTF October 2013 Marco Garattini INFN - Roma “La Sapienza” CERN – 5-7 November 2013 – UA9 Collaboration meeting

Outline The BTF in Frascati (LNF-INFN) Hardware tested in BTF New BTF setup INFN Cerenkov - On Line analysis - First conclusions Marco Garattini, CERN

LINAC tunnel DAΦNE main ring BTF Hall momentum analyzer Characteristics of the e- BTF Particles number: e-/pulse Energy: 25 – 500 MeV Frequency: 20 Hz Pulse duration: 10 ns The Beam Test Facility BTF Team L. Foggetta B. Buonomo G. Mazzitelli P. Valente DAΦNE

INFN Cerenkov: Gianluca Cavoto (Roma1) Francesco Iacoangeli (Roma1) Marco Garattini (Roma1) LAL Cerenkov: Veronique Puill (LAL Orsay) Leonid Burmistrov (LAL Orsay) Jean-François Vagnucci (LAL Orsay) CERN Diamonds: Florian Burkart (CERN) Oliver Stein (CERN) Gerardo Claps Fabrizio Murtas (INFN-CERN ) Hardware tested in BTF Thanks also to W. Scandale & S. Montesano for their important support during the shifts in BTF

Last BTF tests (July 2013) Conclusions: INFN Cerenkov Radiator: we easily saw Cerenkov light even with few particles (“simple” PMT, not MPC) 47º configuration is much better for two reasons - More light transmitted through the radiator - More light accepted into the fibers We have acquired many data (as waveform): timing and resolution of detectors and of different configuration will be studied Marco Garattini, CERN

Hardware tested in BTF (14-20) October INFN: - Cerenkov: - Optical coupling fibers–quartz - Fibers–MCP-PMT (Micro Channel Plate) coupling - Response tests for single particle and many particles in bunch - Response test at different angle wrt the beam direction LAL: - Cerenkov: - Optical coupling fibers–quartz - Fibers–PMT coupling - Response tests for single particle and many particles in bunch - High Immunity Coaxial Cable: test for LHC CERN: - MediPix: to measure in real time the shape of the beam - Diamond : Rad-Hard, fast (1 ns), high fluxes (10 7 part/cm 2 /sec)

BTF setup MP: (MediPix) LAL: Cerenkov (also with gonio…) C: Cerenkov with quartz fibers (Roma1) D: Diamond (Frascati CERN-Florian Burkart) Cal: BTF Calorimeter Pb Glass (multiplicity meas.) Beam Horizontal Rail cart LALMP C D gonio BTF table Cal Marco Garattini, CERN

BTF Setup INFN Cerenkov LAL Cerenkov BTF Calorimeter Diamond e- Beam BTF Remote Control Table Marco Garattini, CERN

BTF Beam along the rail The beam is strongly perturbed by each detector, so we had to test a each single detector at a time E = 446 MeV

INFN Cerenkov Use silica radiator bar provided by Ivanov Observe Cerenkov radiation with MCP-PMT Hamamatsu Use direct optical coupling of MCP-PMT window to the bar Measure Cerenkov rad. at different angle wrt to the incoming beam using a gonio Alternatively use bundle of silica fibers in between bar and MCP-PMT window RM bundle 12,5 cm Industrial bundle 47 cm

Fiber’s bundles Fibers: Fibertech Type AS600/660 UVST Coating 780 μm Silicone Jacket 940 μm Tefzel 0.6 dB/m at 350 nm Bandle 1 (“RM”): -Homemade -Fibers hand-cut by diamond wheel -lapped with glass sand papers with increasing grit ( ) -Length: ~ 13 cm Bandle 2 (“Industrial”): -Manufactured by Fibernet -lapped with industrial lapping process -Length: ~ 47cm -1 fiber cracked on manufacturing  We tested 2 different bundles of same fibers

Direct contact VS Fibers The light yield with fibers bundle are 30 times less: 3.3 % wrt the direct contact between radiator and MPC-PMT 47˚ Charge signal normalized to number of incident electron and electron path length in the radiator Radiator rotation angle Optical grease at interfaces between fibers, PMT and radiator Marco Garattini, CERN

Radiator with fibers bundle Charge signal normalized to number of incident electron and electron path length in the radiator (arbitrary units) Radiator rotation angle - 47º

Lower light collection efficiency due to geometry: MCP-PMT area: π(11mm/2) 2 =95 mm 2 Fibers cable area: 25π*(0.6mm/2) 2 =7.07mm 2 Geometrical efficency ratio: 7/95 = ~7 % Geometrical efficency and optical coupling 10 mm 20 mm Remaining efficiency losses due to optical coupling and fibers attenuation = 7/3.3 = ~ 50 % Electron’s beam 75 mm ± 5 mm Bundle of fiber spot New fibers without jacket and a thinner coating to obtain a better packaging of the fibers in the bundle, and a better geometry efficency

̴ 35˚ shoulder: geometric explanation? Without Teflon RM Fibers 8 mm away RM fibers bundle Industrial fibers bundle Quarz 35˚ This effect is “type fibers boundle or teflon independent” and desappear without fibers. Due to the tip geometry of the quarz radiator? We need of some simulation to better understend.

For all the angular scans we used 100 e- bunch We did an intensity scan: good signal also at few particles N(e) pV·s

 We sow (like LAL Cerenkov) until 2 particles but : - The MPC-PMT is not optimazed to distinguish single particles - We needs some “event per event” data analysis to compare calorimeter and MPC-PMT output signal  With the MPC-PMT we have a ̴ 100 ps resolution: - We can see the multibunching Marco Garattini, CERN

First Conclusions INFN Cerenkov: With both fibers bundles is shown the same Cerenkov light transmission shape: peak at ~ -47º (and shoulder at ~ -35º). The Leonid Geant 4 simulation are confirmed Arbitrary unit, but normalized on the number of electrons and on the path length: The RM “home made” bundle and Industrial one are similar The white teflon around the radiator reduce the light yield Leave a space between radiator and fibers reduces the light yield MCP-PMT directly connected (no fibers):59 Industrial bundle1.26 (but longer) RM “home made bundle”1.92 (but shorter) RM bundle 8 mm away from the radiator1.47 Without teflon around the radiator + RM bundle2.15

The axis of the fibers must be parallel to the direction of emission of Cherenkov light (i.e. “the finger can” also be orthogonal to the direction of the incident particles but the fibers have to be parallel to the Cherenkov light): finger cut to 47º? Quartz Fibers ̴ 43˚ Beam LAL Cerenkov: Leonid Burmistrov next talk Diamonds: Fabrizio Murtas next talk Marco Garattini, CERN

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Test Ethernet BTF Calo (Pb Glass Cerenkov ) Control Room PC -Test of Čerenkov Radiator was done on 8-13 July The DAFNE Beam-Test Facility ( LNF – Frascati (RM) ) by fine-adjustable- multiplicity 500MeV electron’s beam -Čerenkov Calorimeter downstream to measure rate and multiplicity of particle -Signals were acquired by two 4 channels Lecroy Oscilloscope (WaveRunner 625zi and WaveRunner 6050) -System was connected by control room by ethernet Oscilloscope Čerenkov Radiator Beam window Hand Platform Rotation Stage (Newport M-RS 40) FAN-IN/OUT Summed Signal MA PMT Signals

BTF Beam before INFN Cerenkov

Measuremets dettails Use an intense beam 100 e- per bucket at E = 446 MeV Rotate radiator and fiber bundle with a goniometer Charge signal normalized to number of incident electron and electron path length in the radiator Peak expected at Cherenkov angle (-47º) Peak width due to fibers numerical aperture Other feature due to radiator geometry

Radiator with fibers bundle Radiator rotation angle Charge signal normalized to number of incident electron and electron path length in the radiator (arbitrary units) - 47º