1. Proximity focusing RICH detector based on multilayer silica aerogel radiator
R.DeLeo1,A.G.Argentieri2,T.Bellunato3,M.Calvi3,E.Cisbani4,F.Cusanno4,F.Garibaldi4,L.Lagamba1,
E.Nappi1,M.Marra2,S.Marrone1,C.Matteuzzi3,P.Musico5,D.L.Perego3,S.Torrioli4,I.Vilardi1
1University & INFN - Bari, 2Politecnico of Bari, 3University & INFN - Milano Bicocca, 4ISS & INFN - Roma, 5INFN - Genova
Physics Motivations
Perform p-K separation with a proximity focus Ring Imaging Cherenkov (RICH) detector with a multilayer aerogel (n~1.05) as radiator. Fit in a very tight space.
A multilayer Aerogel Block
A hygroscopic monolith aerogel with three layers (BINP-Novosibirk), and its refraction index profile
One, two, and a multilayer aerogel tiles. Two layers double Cerenkov photons (2N1) and Cerenkov angle uncertainty (2s1). A multi(two)layer doubles only Cerenkov photons.
Photon detectors
2”x2” Hamamatsu H9500 PMTs, 16x16 2.8x2.8 mm2 channels, bialkali photocathode, single photon capability
Custom electronics
Based on MAROC2 (IN2P3-LAL, Orsay, a VLSI 64-channel front-end chip, analog multiplexed track-and-hold and binary parallel otutputs), placed on a Front-End card (FE) controlled by a FPGA. FE cards communicate with a Control Board (CB) board, also FPGA-based, via a VME-like bus, the Backplane (BP)
Performance of Photon detectors
the single photo-electron spectrum in one channel of a H9500
20-30 kHz counting rate for a 5% of occupancy in 8 H9500s
Test results with 500 MeV electrons at Frascati BTF
Exp.setup: aerogel and 8 H9500s
# of Cerenkov photons, ring radius, single photon sq vs
aerogel-PMTs distance
Aerogel sq per ring (mrad)
4 tiles
1 multi(4)layer
Overlap of Cerenkov rings
FRONTIER DETECTORS FOR FRONTIER PHYSICS May 2009 La Biodola, Isola d'Elba, Italy