1 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE COMPASS RICH-1: PROGETTO THGEM S. Dalla Torre

2 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE COMPASS RICH-1, OGGI

3 COMPASS RICH-1 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE hadron PID from 3 to 50 GeV/c radiator: C 4 F 10 5 m 6 m 3 m MWPC’s + CsI UV mirror wall Al vessel radiator gas: C 4 F 10 beam pipe PD’s: ~6 m 2 MAPMT’s+lenses P. Abbon et al., NIMA 587 (2008) 371, NIMA 616 (2010) 21, NIMA 631 (2011) 26 PMT’s MWPC’s + CsI

4 LO STATO DEI FOTORIVELATORI A GAS CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE Evidence for a QE degradation: Integration of polluting impurities ? 20V lower HV Nuova cesiatura ? una quantita’ di lavoro compararbile all’assemblaggio e montaggio di nuovi rivelatori, cioe’ circa il 40% del lavoro totale necessario per i nuovi fotorivelatori RECALL: manutenzioni ordinarie e reperibilita’: 2 anni-uomo/anno

5 PERCHE’ NUOVI FOTORIVELATORI A GAS ? MWPCs with CsI photocathode, the limits  Severe recovery time (~ 1 d) after detector trips  Ion accumulation at the photocathode moderate gain:<10 5  Feedback pulses  Feedback pulses (effective gain: <1/2)  Ion and photons feedback from the multiplication process not fast !  Aging after integrating a few mC / cm 2  Ion bombardment of the photocathode CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE H. Hoedlmoser et al., NIM A 574 (2007) mC/cm mC/cm 2 MWPCs  slow signal formation + low gain  “slow” electronics (signal integration, low noise level)   Gassiplex FE : integration time ~ 0.5  s, time res> 1  s, effective gain ~50%   APV (COMPASS RICH-1 upgrade) : resolution for small signals ~ 400 ns, effective gain ~ 30%  Detector memory, i.e. RATE LIMITATIONS

6 NOVEL GASEOUS PHOTON DETECTORS TWO REQUESTS  Reduced photon and Ion BackFlow (IBF)  Reduced aging  High gain  high photoelectron detection efficiency  Intrinsically fast gaseous detectors (signal due to electron motion)  Short integration time  High rate environments MICROPATTERN GASEOUS DETECTORS MICROPATTERN GASEOUS DETECTORS CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

7 R & D

8 GOAL: THGEM-BASED PD THE ARCHITECTURE  The upper THGEM layer is coated with a CsI film  The pe multiplication is obtained with 3 THGEM layers  The signal is collected at the anode, segmented in pads  The filed above the first THGEM is defined by a wire plane  A second wire plane screens the quartz window CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE Wires (Drift) Wires (protection) camere che includono 2 moduli da 600 x 600

9 STUDIO SISTEMATICO DELLE THGEM CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE R3R3 P1P1 W2W2 P 1 : D=0.8 mm Pitch=2 mm Rim=0.04 mm Thick=1mm R 3 : D=0.2 mm Pitch=0.5 mm Rim=0.01 mm Thick=0.2mm W 2 : D=0.3 mm Pitch=0.7 mm Rim=0.1 mm Thick=0.4mm A MULTIPARAMETER SPACE TO EXPLORE ! 4 geometrical parameters: diameter pitch rim thickness + material + production procedure > 50 different THGEMs characterized A MULTIPARAMETER SPACE TO EXPLORE ! 4 geometrical parameters: diameter pitch rim thickness + material + production procedure

10 pe - EXTRACTION CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE photoelectron trajectories from a THGEM photocathode, simulation, multiplication switched off Thickn. 0.6 mm, diam. 0.4 mm, pitch: 0.8 mm, ΔV = 1500 V photoelectron lost (not enterig the holes) E = V E = 500 V photoelectron lost ( filed too low for extraction) x cross-section field above the THGEM E = 0 x y Ar/CH 4 : 40/60; 60/40  V = 1kV 1.1, , external electric field applied Anodic current (pA)

11 RISPOSTA TEMPORALE E ESTRAZIONE pe CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE Outside the gaussian peak:

12 PHOTON DETECTION & DIGITAL R-O CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE Digital R-O: MAPMT R-O, i.e. C-MAD + F1  consistency  pe detection efficiency : 75%   NEW! Now operational with threshold at 2 fC  pe detection efficiency 83% ! Threshold curve (C-MAD) min. thr. : 3 fC 0.7 * 10 5 padmultiplicity amplitude spectrum (all pads, // r-o ) Time spectra vs threshold setting 3.5 fC 2 fC 1 fC

13 TEST BEAM (2009, 2010) CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE Chamber with 1 MAPMT and 3 triple THGEM photon detector prototypes installed CERN SPS T2-H4 beam line (RD51 test beam) 150 Gev/c, beam spot s ~12 mm, rate ~1 kHz ns

14 IL PROTOTIPO INGEGNERIZZATO 300 x 300 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

15 IL PROTOTIPO INGEGNERIZZATO 300 x 300 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE  Test beam VI-VII/11   ~ cancellato (no beam to NA)  Emergenza  test beam VIII/11   Lavoro raddoppiato, squadra formate in emergenza Chamber stable at the test beam with gains up to 10 5 Chamber stable at the test beam with gains up to 10 5  Beam region, MIP rate: 100 Hz / cm  First rings in a large size THGEM photon detectors (collected on 20/8/2011, analysis on going)

16 IL PROTOTIPO INGEGNERIZZATO 300 x 300 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE  Test beam VI-VII/11   ~ cancellato (no beam to NA)  Emergenza  test beam VIII/11   Lavoro raddoppiato, squadra formate in emergenza Chamber stable at the test beam with gains up to 10 5 Chamber stable at the test beam with gains up to 10 5  Beam region, MIP rate: 100 Hz / cm  First rings in a large size THGEM photon detectors (collected on 20/8/2011, analysis on going)

17 LA CONCLUSIONE DELL’R & D  APPORTARE AL PROTOTIPO 300 X 300 mm 2 LE MIGLIORIE SUGGERITE DAI TEST (LABORATORIO, TEST BEAM)  REALIZZARE UN PROTOTIPO DI DIMENSIONI FINALI : 600 X 600 mm 2  PRONTI A COSTRUIRE NEL 2012 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

18 R&D E CONTESTO INTERNAZIONALE CONFERENZE (OTT – SETT 2011)  F. Tessarotto, “The COMPASS RICH-1 Detector”, invited talk at the International Workshop on Probing Strangeness in Hard Processes, Laboratori Nazionali di Frascati (Italia), ottobre  S. Levorato, ”Rivelazione di fotoni singoli con contatori basati su Thick GEM”, poster, IFAE, Perugia (Italia), aprile  F. Tessarotto “Development of THGEM-based photon detectors for the upgrade of COMPASS RICH-1”, talk, TIPP2011, Chicago, 9-14 giugno  S. Levorato, “Detection of single photons with ThickGEM-based counters“, talk, NDIP2011, Lione (Francia), 4 – 8 luglio  S. Dalla Torre, “Novel photon detectors based on ThickGEM technology for COMPASS RICH-1”, CERN Detector seminar, CERN, 15 luglio  S. Dalla Torre, “Detection of single photons with ThickGEM-based counters”, talk, MPGD2011, Kobe (Giappone), 28 agosto – 1 settembre CONTESTI nei quali il progetto e’ apprezzato  RD51 (collaborazione tecnologica, si veda G. Catanesi 19/9)  HP2, HP3 (Integrated Infrastructure Initiative, UE) CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

19 RICH + R&D, documentazione scientifica PUBBLICAZIONI (OTT – SETT. 2011)  M. Alexeev et al, “Micropattern gaseous photon detectors for Cherenkov imaging counters”, Nucl. Instr. and Meth. A 623 (2010) ;  P. Abbon et al, “Particle identification with the fast COMPASS RICH-1 detector”, Nucl. Instr. and Meth. A 623 (2010) ;  P. Abbon et al, “Particle identification with COMPASS RICH-1” Nucl. Instr. and Meth. A 631, (2011), 26;  S. Dalla Torre, “Status and perspectives of gaseous photon detectors”, Nucl. Instr. and Meth. A 639 (2011), 111;  S. Dalla Torre et al., “A study of the RICH gas refractive index”, Nucl. Instr. and Meth. A 639 (2011), 271;  P. Abbon et al, “The experience of building and operating COMPASS RICH-1”, Nucl. Instr. and Meth. A 639 (2011), 15;  M. Alexeev et al, “Progress towards a THGEM-based detector of single photons”, Nucl. Instr. and Meth. A 639(2011), 130;  M. Alexeev et al, “Mirror alignment control for COMPASS RICH-1 detector”, Nucl. Instr. and Meth. A 639 (2011), 211. CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

20 LA SQUADRA CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE R & D  Aveiro (new since 1 y: a professor and 2 students)  Freiburg  Liberec-Prague (a professor and 1-2 students)  Torino - Alessandria  Trieste COSTRUZIONI  Freiburg  Torino - Alessandria  Trieste  Some (small) contributions from Aveiro, Liberec-Prague under discussed

21 SUPPORTO DA CSN I  k€  k€  k€  k€ + ME, in totale ~ 50 k€ INVESTIMENTO GLOBALE DELLA CSN I ~300 k€ DELLA CSN I ~300 k€ CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE

22 CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE UNA PAROLA SUL TUBO

23 BEAM PIPE, OGGI CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE radiator: C 4 F 10 5 m 6 m 3 m MWPC’s + CsI UV mirror wall Al vessel radiator gas: C 4 F 10 beam pipe PD’s: ~6 m 2 MAPMT’s+lenses Acciao inox L: 3.3 m Ø : 10 cm spessore laterale : 150  m spessore estremita’: 100  m ALL’INTERNO: He P TUBO = P VESSEL + 1 mbar (-5 / +15 mbar)

24 BEAM PIPE, LE NUOVE ESIGENZE CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE  Tubo attuale   progettato in funzione della spettroscopia adronica   realizzato nell’ inverno  Oggi non compatibile con il nuovo programma di fisica Pisa 12/9/2011 RICH & THGEM Silvia DALLA TORRE Studi MC per le misure DVCS Dati, test Primakoff 2009

25 Prototipi e sistemi di test per un tubo leggero CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE 200 mm Tubo in acciaio

26 Prototipi e sistemi di test per un tubo leggero CSN I, BARI 19-13/9/2011 RICH&THGEMSilvia DALLA TORRE 200 mm Tubo in acciaio