CERN Accelerating science

Article
Title	Optical telescopes for COMPASS RICH1 up-grade
Author(s)	Sulc, M (Liberec Tech. U.) ; Abbon, P (DSM, DAPNIA, Saclay) ; Alekseev, M (INFN, Turin ; Turin U.) ; Angerer, H (Munich, Tech. U.) ; Appolonio, M (INFN, Trieste ; Trieste U.) ; Birsa, R (INFN, Trieste ; Trieste U.) ; Bordalo, P (Lisbon, LIFEP) ; Bradamante, F (INFN, Trieste ; Trieste U.) ; Bressan, A (INFN, Trieste ; Trieste U.) ; Busso, L (INFN, Turin ; Turin U.) ; Chiosso, V M (INFN, Turin ; Turin U.) ; Ciliberti, P (INFN, Trieste ; Trieste U.) ; Colantoni, M L (INFN, Turin ; Piemonte Orientale U., Alessandria) ; Costa, S (INFN, Turin ; Turin U.) ; Dibiase, N (INFN, Turin ; Turin U.) ; Dafni, T (DSM, DAPNIA, Saclay) ; Dalla Torre, S (INFN, Trieste ; Trieste U.) ; Diaz, V (INFN, Trieste ; Trieste U.) ; Duic, V (INFN, Trieste ; Trieste U.) ; Delagnes, E (DSM, DAPNIA, Saclay) ; Deschamps, H (DSM, DAPNIA, Saclay) ; Eyrich, W (Erlangen - Nuremberg U.) ; Faso, D (INFN, Turin ; Turin U.) ; Ferrero, A (INFN, Turin ; Turin U.) ; Finger, M (Charles U. ; Dubna, JINR) ; Finger, M Jr (Charles U. ; Dubna, JINR) ; Fischer, H (Freiburg U.) ; Gerassimov, S (Munich, Tech. U.) ; Giorgi, M (INFN, Trieste ; Trieste U.) ; Gobbo, B (INFN, Trieste ; Trieste U.) ; Hagemann, R (Freiburg U.) ; von Harrach, D (Mainz U., Inst. Kernphys.) ; Heinsius, F H (Freiburg U.) ; Joosten, R (Bonn U., HISKP) ; Ketzer, B (Munich, Tech. U.) ; Königsmann, K (Freiburg U.) ; Kolosov, V N (CERN) ; Konorov, I (Munich, Tech. U.) ; Kramer, D (Liberec Tech. U.) ; Kunne, F (DSM, DAPNIA, Saclay) ; Levorato, S (INFN, Trieste ; Trieste U.) ; Maggiora, A (INFN, Turin ; Turin U.) ; Magnon, A (DSM, DAPNIA, Saclay) ; Mann, A (Munich, Tech. U.) ; Martin, A (INFN, Trieste ; Trieste U.) ; Menon, G (INFN, Trieste ; Trieste U.) ; Mutter, A (Freiburg U.) ; Nähle, O (Bonn U., HISKP) ; Neyret, D (DSM, DAPNIA, Saclay) ; Nerling, F (Freiburg U.) ; Pagano, P (INFN, Trieste ; Trieste U.) ; Paul, S (Munich, Tech. U.) ; Panebianco, S (DSM, DAPNIA, Saclay) ; Panzieri, D (INFN, Turin ; Piemonte Orientale U., Alessandria) ; Pesaro, G (INFN, Trieste ; Trieste U.) ; Pizzolotto, C (Erlangen - Nuremberg U.) ; Polak, J (Liberec Tech. U.) ; Rebourgeard, P (DSM, DAPNIA, Saclay) ; Rocco, E (INFN, Trieste ; Trieste U.) ; Robinet, F (DSM, DAPNIA, Saclay) ; Schiavon, P (INFN, Trieste ; Trieste U.) ; Schill, C (Freiburg U.) ; Schoenmeier, P (Erlangen - Nuremberg U.) ; Silva, L (Lisbon, LIFEP) ; Slunecka, M (Charles U. ; Dubna, JINR) ; Steiger, L (Liberec Tech. U.) ; Sozzi, F (INFN, Trieste ; Trieste U.) ; Svec, M (Liberec Tech. U.) ; Tessarotto, F (INFN, Trieste ; Trieste U.) ; Teufel, A (Erlangen - Nuremberg U.) ; Wollny, H (Freiburg U.)
Publication	2006
Number of pages	8
In:	Czechoslov. J. Phys. 56 (2006) pp.F325
In:	Advanced Studies Institution Symmetries and Spin, Prague, Czech Republic, 19 - 26 Jul 2006, pp.325
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN SPS ; COMPASS NA58
Abstract	The central photon detection area of the Ring Imaging Cherenkov detector at COMPASS, a particle physics experiment at CERN SPS dedicated to hadron physics, has been upgraded from the previous system formed by wire chambers with CsI layers to a very fast UV extended multi anode photo multiplier tube array (MAPMT), including 576 tubes. The active area covered by the MAPMTs is 7.3 times smaller than the one previously equipped with CsI photocathodes, so 576 optical concentrators transforming the image from the old system focal plane to the new photocathode plane were needed. The telescope system formed by two fused silica lenses was designed, produced and assembled. The first prismatic plano-convex field lens is placed in the focal plane of the RICH mirrors. The second condenser lens is off centered and tilted and has one aspherical surface. All lenses have antireflection coating.