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CMS Frascati. L.Benussi, M.Bertani, S.Bianco, A.Brotzu,M.A.Caponero, S.Colafranceschi, D.Colonna , D.Donisi, F.L.Fabbri, F.Felli, M.Giardoni, T.Greco, B.Ortenzi, M.Pallotta, A.Paolozzi, L.Passamonti, D.Pierluigi, A.Russo, B.Ponzio, C.Pucci, G.Saviano. Attivita` 2007 CMS Frascati.
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CMS Frascati L.Benussi, M.Bertani, S.Bianco, A.Brotzu,M.A.Caponero, S.Colafranceschi, D.Colonna, D.Donisi, F.L.Fabbri, F.Felli, M.Giardoni, T.Greco, B.Ortenzi, M.Pallotta, A.Paolozzi, L.Passamonti, D.Pierluigi, A.Russo, B.Ponzio, C.Pucci, G.Saviano S.Bianco CMS Frascati - Incontro Referee
Attivita` 2007 CMS Frascati • Sviluppo e realizzazione del Gas Gain Monitoring System S.Bianco on behalf of the CMS RPC Collaboration, “The gas gain monitoring system for the CMS RPC detector”, IEEE06, San Diego (USA) http://arxiv.org/pdf/physics/0701014. • Sistema di 12 RPC 50cm x 50cm per il monitoring con cosmici delle variazioni del punto di lavoro dovute alle variazione nella composizione del gas e alla presenza di contaminanti. In un unico telescopio tre sottosistemi alimentati da fresh Mix, pre-Purifiers, post-Purifiers • Il sistema e` funzionante ed in corso di commissioning a Frascati • Scrittura di programmi xDAQ e, successivamente, PVSS iniziata (S.Colafranceschi) • La gas room @ SX5 non sara’ pronta prima di settembre 2007 --> installiamo il sistema al Closed Loop dell’ISR, schedule: • 24 LUGLIO Inizio installazione elettronica, cavi, PC, derivazione gas etc • 3 SETTEMBRE trasporto sistema al CERN, installazione, inizio commissioning • 31 DICEMBRE (milestone) sistema operativo al CERN • Studi del Closed Loop e test all’ISRM.Abbrescia et al., Proposal for a detailed study of Closed Loop… Frascati Preprint LNF 06/27 (IR) available at http://www.lnf.infn.it/sis/preprint/ • Iniziata una campagna di studio del Closed Loop con prelievi sistematici di materiale dei filtri e di gas, e analisi chimiche a largo spettro. Risultati mostrano che le procedure di rigenerazione vanno capite meglio, e che va studiato il possibile rilascio di elementi dai filtri. • In preparazione nuova serie di analisi chimiche piu` mirate • Test del Closed Loop attualmente operativo con poche camere di vecchia produzione, nuove gaps attese a fine settembre. • Person power: laureando Frascati (luglio-agosto-settembre) + summer student. • Installazione e commissioning, shifts • Studi di ageing delle RPC S.Bianco CMS Frascati - Incontro Referee
Gas Gain Monitor (conceptual design) USC5 UXC5 VENT RPC TRIG1 RPC TRIG2 Slow Ctrl GC, p/T/RH/Ph MONITOR VENT RPC PAD MON1 RPC PAD MON2 RPC PAD MON3 VENT RPC PAD MON4 RPC PAD MON5 CMS RPC PAD MON6 PURIFIERS REFERENCE half wheel lines VENT RPC PAD REF1 C2H2F4/SF6 /i-C4H10 /H2O RPC PAD REF2 VENT RPC TRIG3 RPC TRIG4 SGX Bldg S.Bianco CMS Frascati - Incontro Referee
Gas gain monitoring chambers Positive pad knee +200 -200 CMS RPC preliminary 0.0% SF6 Negative pad 0.3% SF6 Monitoring della purezza del gas attraverso il controllo del punto di lavoro di 12 piccole gaps 50cm x 50cm, doppio pad readout @ GT STREAMER AVALANCHE @ Frascati, test in ambiente umidita` controllata S.Bianco CMS Frascati - Incontro Referee
Closed loop Studies Summary • Closed loop filters determined in 2001 at GIF by looking at GC peaks • Purifiers in CMS will need daily regeneration, optimize purifier materials is a must • Rigorous sampling of purifiers performed: • New materials • Used materials • Regenerated materials • A broad-spectrum analysis campaign (reference) to single out problems and to design more focussed analyses. • Test ongoing now at ISR with 20 Double-gap RPC’s to characterize purifiers S.Bianco CMS Frascati - Incontro Referee
La rigenerazione non rimuove S e F dai filtri CMS PRELIMINARY S.Bianco CMS Frascati - Incontro Referee
Elementi in traccia nelle bachelitiIl gas riduce la presenza di metalli sulle bacheliti CMS PRELIMINARY S.Bianco CMS Frascati - Incontro Referee
Andamento di Cu Zn Pb Ni nelle zeolitiLa rigenerazione non rimuove i metalli dalle zeoliti CMS PRELIMINARY S.Bianco CMS Frascati - Incontro Referee
MOF-B richieste 2008 Le richieste si riferiscono al sistema di gas gain monitoring descritto in [1], e alle analisi per lo studio sistematico di filtri e gas del Closed Loop (rif.[2]) attualmente in corso all'ISR e vengono meglio dettagliate come segue: 1) ANALISI CHIMICHE ................ 6.0kEURO Analisi chimiche (INAA, Fluorescenza, ICP-MS) da effettuarsi esternamente a completamento della prima fase di caratterizzazione dei filtri [2]. Materiali di consumo e reagenti per il completamento dello studio delle caratteristiche dei filtri dopo il filtraggio e le operazioni di rigenerazione degli stessi da effettuarsi a cura del gruppo di Frascati. 2) POOL AFFITTO ELETTRONICA GAS GAIN MONITORING ........ 8.0kEURO Elettronica di HV, LV, preamplificazione e logica di trigger per le camere del gas gain monitoring. Si propone di mantenere nel 2008 il sistema finanziato a Frascati ed utilizzare affitto di materiale per il sistema al CERN. 3) SPARE PER GAS GAIN MONITORING ................. 7.0kEURO Acquisto di n.15 gaps 50cm*50cm come spare delle n.12 camere del gas gain monitoring. Gli spare saranno realizzati nei primi mesi del 2008, approfittando delle ultime possibilita di produzione prima della chiusura degli impianti della General Tecnica. Il costo e` lo stesso sostenuto per l acquisto delle n.12 camere del sistema attualmente in uso. • BIBLIOGRAFIA [1] M.Abbrescia et al., The Gas Gain monitoring system of CMS RPC, http://arxiv.org/pdf/physics/0701014 [2] M.Abbrescia et al., Proposal for a Systematic Study of the CERN Closed Loop Gas System Used by the RPC Muon Detectors in CMS, Frascati preprint LNF - 06 / 27(IR). S.Bianco CMS Frascati - Incontro Referee
Papers 2006-2007 • Preprints and Conferences • S.Bianco on behalf of the CMS RPC Collaboration, “The gas gain monitoring system for the CMS RPC detector”, IEEE06, San Diego (USA) http://arxiv.org/pdf/physics/0701014. • C.Pucci “CMS RPC gas gain system”, Annual Congress of Italian Physical Society, Torino 2006 • D.Colonna “Use of FBG sensors for high precision silicon detectors”, Annual Congress of Italian Physical Society, Torino 2006 • M.Abbrescia et al., Proposal for a detailed study of Closed Loop… Frascati Preprint LNF 06/27 (IR) available at http://www.lnf.infn.it/sis/preprint/ • M.Caponero et al., “On the use of FBG sensors in CMS” Siena conference on adv. Detectors Nov 2006 (to appear on NIM) • A.Paolozzi et al., “Performances of FBG sensors for application at LHC experiments”, Vienna conference Feb 2007 (to appear on NIM) • S.Bianco et al., Omega-Like Fiber Bragg Grating Sensors as Position Monitoring Device: A Possible Pixel Position Detector in CMS? Frascati preprint LNF- 06/13(NT) • Masters and PhD Theses • C.Pucci Analisi dei materiali nelle RPC di CMS Frascati preprint LNF - 06 / 31(Thesis) • D.Colonna Applicazione dei sensori FBG in HEP e nelle strutture Marzo 2007 S.Bianco CMS Frascati - Incontro Referee
CMS Frascati Activity in 2008 • Commissioning, data taking • Commissioning of gas gain monitoring • Study of closed loop at ISR • Physics studies: Channels with muon pairs (from J/psi, Upsilon(4s), Z0), profiting of knowledge of RPC and DT muon detectors • Spectroscopy of Bc-->J/psi , B--> • Primi pensieri su S-LHC (gems, thin gap rpc, etc) S.Bianco CMS Frascati - Incontro Referee
CMS Frascati 2008 Ricercatori & Tecnologi Bertani 20%, Bianco 80% Caponero 50%, Colafranceschi 100% Donisi 100%, Fabbri 70%, Felli 100%, Giardoni 60%, Pallotta 30%, Paolozzi 30%, Piga 100%, Pucci 100%, Saviano 100% TOT=9.4 FTE Tecnici Ortenzi 100%, Passamonti 20% Collaborano: B.Ponzio D.Pierluigi, A.Russo Laureandi Greci S.Bianco CMS Frascati - Incontro Referee
SPARE SLIDES S.Bianco CMS Frascati - Incontro Referee
SEM image of a defect with two magnifications SEM-EDS STUDY OF IRRADIATED RPCs • We opened RPCs irradiated at the GIF and observed defects on the inner surfaces. Anode Cathode • We performed SEM-EDS and XRD analyses on- and off-defect… S.Bianco CMS Frascati - Incontro Referee
CLOSED LOOP GAS RECIRCULATION Purifiers are THE crucial component S.Bianco CMS Frascati - Incontro Referee
GAS STUDIES • Resistive Plate Chambers (RPC) detectors are widely used in HEP experiments for muon detection and triggering at high-energy, high-luminosity hadron colliders, in astroparticle physics experiments for the detection of extended air showers, as well as in medical and imaging applications. • While gain and efficiency stability are always a must, in the case of RPC detectors in high-rate experiments which use freon-based gas mixtures, utmost care has to be paid also for the possible presence of gas contaminants. • The RPC detector of experiment CMS at the LHC proton collider (CERN, Switzerland) will employ a gas analysis and monitoring system for the online monitor of the freon-based gas mixture used. • The gas monitoring system is based on small RPC detectors whose working point (gain and efficiency) is continuously monitored online. The gas monitoring system is designed to provide fast and accurate determination of any shift in working point conditions. • Quantitative gas chemical analysis is then performed online by a complete system which includes gas-chromatography, pH sensors and contaminants (notably HF) detectors. S.Bianco CMS Frascati - Incontro Referee
SEM / EDS analysis of defects inside irradiated RPC F peak Reference bakelite On-defect Peaks of defects Na peak On-defect Off-defect Peaks of NaF • Presence of Na in defects from bakelite • Preliminary XRD results show presence of NaF. http://arxiv.org/pdf/physics/0701014. S.Bianco CMS Frascati - Incontro Referee
CERN Closed Loop Gas System • We proposed to study presence of contaminants and their type ofaccumulation in the Closed Loop Gas system (same for CMS and ATLAS) • Current values in ISR Test Chambers decrease as the gas circulation changes from a closed to an open loop • We are coordinating a three-phase study of CL • Phase 1 September 06 - study contemporaneous to chamber testing. Limited by current values. • Phase 2 March 07 - Dedicated testing of DG’s and SG’s • Phase 3 ? - Dedicated testing at GIF possibly synergy with ATLAS S.Bianco CMS Frascati - Incontro Referee
CERN Closed Loop Gas system • All system components should be characterized: • Bakelite (all different types of bakelite) • Zeolite (all different zeolite filters) • Other filters based on Cu and Zn and oxides • Gas by means of a systematic sampling of the different parts during all of the system work phases S.Bianco CMS Frascati - Incontro Referee
Phase 1: ISR sampling September 2006 • Samples (unused, contaminated, regenerated) have been collected: • Purifiers: • Zeolite • Ni Al2O3; • Cu, Cu Zn • Pipes Cu • Neither oiled nor used bakelite • Unused bakelite oiled with graphite S.Bianco CMS Frascati - Incontro Referee
Table of analyses S.Bianco CMS Frascati - Incontro Referee
Different zeolite filters have been used : 3A, 5A. They differ in their grain size dimensions, framework pores amplitude and chemical composition 4A (4 Å, Na) 3A (3 Å, K) 5A (5 Å, Ca) Grain size distribution has been performed on zeolite filters : 3Å (25 gr) 1,4 mm (8 gr) 1 mm (17 gr) 5Å (25 gr) 2,8 mm (16 gr) 2 mm (9 gr) Zeolites characterization now used in CL S.Bianco CMS Frascati - Incontro Referee
Framework of Linde Type A zeolites 4A (4 Å, Na) 3A (3 Å, K) 5A (5 Å, Ca) Type A zeolites S.Bianco CMS Frascati - Incontro Referee
Linde Type A zeolite (Na96(H2O)216[Si96Al96O384] REFERENCE XRD performed at University of Rome “La Sapienza” on a sample of unused zeolite. On the right, the reference pattern for standard Linde Type A zeolite. S.Bianco CMS Frascati - Incontro Referee
RACKS LAYOUT IN SGX5 Only gas, no electronics 11 12 1 and 1/2 racks For gas gain monitor Gas quality here + piping,valves,GC ? Minimize signal cables lengths Lateral access S.Bianco CMS Frascati - Incontro Referee
Integration of Gas Gain Monitoring gaps with the CERN gas system S.Bianco CMS Frascati - Incontro Referee
GAIN MONITORING SYSTEM Foam READOUT PAD S.Bianco CMS Frascati - Incontro Referee
GAS GAIN MONITORING - DOUBLE PAD READOUT Pads 45x45cm2 positive and negative Cosmic ray event triggered by scintillation counters hodoscope DEVELOPING DIFFERENTIAL AMPLIFICATION SCHEME TO REDUCE COHERENT NOISE Sum pulse S.Bianco CMS Frascati - Incontro Referee
Our FEE options under test 1/6 Several amplification schemes are being explored. Even a simple passive sum of positive and negative pads and feeding to standard LRS612AMampli improves the S/N ratio. Type A0 - LM6172 - Dual High Speed, Low Power, Low Distortion Voltage Feedback Amplifiers Gain Bandwidth 100 MHz Slew Rate 3000 Volts/usec SupplyCurrent Per Channel 2.3 mA Supply Min 5.5 Volt Supply Max 36 Volt TRASFORMATORI (Zero centrale) Tipo A Ferrite Diametro 30mm spessore 6mmTipo B Ferrite Diametro 30mmspessore 12mmTipo C Miniatura diametro 6mm spessore 3mm Type A1 - Max 435 Differential, High Speed Op Amp Gain Bandwidth275 MHz Slew Rate 800 Volts/usec SupplyCurrent Per Channel 18 mA Supply Min 5 Volt Supply Max 12 Volt Type A2 - LMH6550 Differential, High Speed Op Amp Gain Bandwidth 400 MHz Slew Rate 3000 Volts/usec SupplyCurrent Per Channel 20 mA Supply Min 5 Volt Supply Max 12 Volt S.Bianco CMS Frascati - Incontro Referee
AMPLI Option Oscilloscopio Lecroy / Tektronix CMS RPC preliminary 10pF 100uH HV=9700V <- PEDESTAL 4uH 10nF S.Bianco CMS Frascati - Incontro Referee