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ATLAS RPC phase-2 proposal

ATLAS RPC phase-2 proposal. Completion of the detector for the barrel muon trigger via the installation of new trigger stations in the inner layer of the spectrometer (currently equipped only with MDTs) Increase the number of measurement stations from 2  3

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ATLAS RPC phase-2 proposal

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  1. ATLAS RPC phase-2 proposal • Completion of the detector for the barrel muon trigger via the installation of new trigger stations in the inner layer of the spectrometer (currently equipped only with MDTs) • Increase the number of measurement stations from 2  3 • Increase the number of independent layers from 6  9 RPC3 RPC2 RPC1 RPC0 (BI) D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  2. ATLAS RPC phase-2 proposal • The inner layer was already considered in the original project of the barrel trigger detector, but at that time the need for the 3rd station was not stringent and it was cancelled • Trigger performance improvements with the new RPC inner layer: • larger acceptance • The new chambers will substantially increase the trigger coverage by filling the acceptance holes due to the barrel toroid support structures • increased selectivity • The larger lever arm and the improved spatial and time resolution of the new RPCs will allow to apply a sharper momentum cut • increased chamber redundancy and longevity • the new layer will increase the redundancy well above the current 3/4 low-pt majority. This will also allow tooperate the middle chambers at lower voltage, decreasing theintegrated charge, without loss in the overall trigger efficiency D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  3. Barrel trigger coverage LVL1 barrel • High-Pt trigger acceptance currently limited at ~72% • due to non-instrumented regions in: • feet + elevators (partial recovery in LS1) • toroid (and ribs) in BM chambers of small sectors • Holes are not projective and 3/3 RPC chambers • are required in the trigger •  with RPC BI chambers use 3/4 request η=0.0 0.4 0.75 1.0 D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  4. Barrel trigger coverage Single muon MC study for different trigger options current trigger logic D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  5. Redundancyexploitation The produced charge, responsible for the detector aging, can be reduced by decreasing the operating voltage (this is equivalent to work at lower rate and much lower current) The detector efficiency will consequently decrease - the loss in efficiency is compensated by a less stringent requirement in low-pt trigger: 3/4 2/4 majority - the rejection power would be guaranteed by the additional RPC in the BI chambers 2/4 3/4 D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  6. Requirements on the new RPCs • According to Atlas requirements the qualification tests were done taking as reference luminosity L=1034 cm-2 s-1, assuming 10 years of running at max background rate of 100 Hz/cm2(including a safety factor of 5 wrt simulation) • Expected max rate in new inner layer ~1 kHz/cm2: • need to improve the long term RPC rate capability to sustain the LHC luminosity in phase-2 • Limited space available for the installation in the inner layer: ~5cm • Reduced gas gain: • thinner gap 2  1 mm • thinner electrodes 1.8  1.2 mm • increased amplification in front-end electronics • Improved spatial and time resolution: • timing is improved by reducing the gap thickness • use ToT and charge centroid to improve spatial resolution • Reduced detector thickness • higher-quality mechanical structures D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  7. CMS RPC phase-2 proposal Two types of upgrades proposed for the CMS RPC muon system: Aging and longevity: built in 2003 and installed in 2007, must continue to operate without significant degradation degradation (<eff> = 95%, CS < 3, noise < 1 Hz/cm2) well beyond the design expectations of the LHC; in particular, with respect to a large integrated radiation dose and also a very long time period of operation. • Upgrade of high eta region: keep performance of trigger and low pT<20GeV threshold even at an increased luminosity • Background rejection and muon reconstruction • Costant trigger rate with PT < 20 GeV • HZZ*2m, 4m; Ht+t-mX; etc • NEW STATIONS RE3/1 and RE4/1 Technical Proposal in progress due July 2014 D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  8. RE3/1 & RE4/1 • Proposed to cover the very forward region (1.6< |h| <2.4) • 144 chambers (about 1.5-2.0 m2 area) for the inner (ring n.1) region of disks 3 and 4 • Rate: 1-2 kHz/cm2 •  x5 limit tested for existing RPC chambers • Integrated charge: 1-2 C/cm2 @ 3000fb-1 Barrel muon system is covered with 8 layers of chambers (58 hits max) Endcap region is covered with 8 layers (28 hits max) High eta region is covered with 4 layers (24 hits max) D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  9. CMS RPC in muon reconstruction • Recovery of efficiency thanks to RPC tracking During RUN1 the stability of the muon system has been assured thanks to the 2 independent trigger/detector systems. A major CSC faults occurred in the 2012 (7 chambers off in ring1) but thanks to the RPC (ring 2) we were able to recover part of the inefficiency even in this region. With a full coverage the system will be stable in case of any trouble. D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  10. CMS RPC in muon trigger • All 3 muon triggers (RPC, DT, CSC) contribute to the stability of the muon trigger efficiency and to the control of the rate. • From the 2016 all the muon data will be used in a unique algorithm in order to have more robust system in the view of the lumi/background increment foreseen. D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  11. Joint ATLAS-CMS phase 2 R&DCMS-specific • Operation at 1-2kHz/cm2, 1-2 C/cm2 @3000fb-1 • Improved time resolution (10-100)ps • Background reduction • Secondary vertices • iRPC • Large area, improved, multigap RPC • with HPL / glass electrodes D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  12. 1. Electrode D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  13. 2. Chamber prototypes D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  14. 3. FEE D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  15. 4. The “ecological” gas mixturesissue • The European Community has prohibited the production and use of gas mixtures with Global Warming Power > 150 (GWP(CO2) = 1) • This is valid mainly for industrial (refrigerator plants) applications • Scientific laboratories would be excluded • CERN could require to stick to these rules anyhow • C2H2F4 is the main component of the present RPC gas mixture: • GWP(C2H2F4) = 1430, GWP(SF6) = 23900, GWP(iC2H10) = 3.3 • C2H2F4and SF6Crucial to ensure a stable working point in avalanche • Similar problem for CF4(GWP = 5800) used in GEMs for time resolution • On the physical and chemical properties of this components we: • Designed FE electronics and chambers • Did all performance, ageing and calibration tests D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  16. 4. The “ecological” gas mixturesissue: Plan • Test moleculessimilar to C2H2F4 but with lower GWP • C3H2F4– tetrafluoropropene (GWP=4) • Should replace C2H2F4 as automotive air-conditioning refrigerant • C2H4F2– difluoroethane (GWP=120) • Also studied to replace C2H2F4 as a refrigerant • C2HF3Cl2 (GWP=93), • others… • Plan to measure all the detector response parameter (time, charge spectrum, streamer separation, noise, efficiency, possibly drift velocity) • HUGE PARAMETER SPACE, NEED TO DIVIDE MEASUREMENTS BETWEEN FACILITIES • Test at the GIF++ will follow on a short list of candidates to measure the performance in a realistic environment • Rate capability, performance under stress, HF yield  already being setup at GIF • New ageing tests (to be performed also at GIF++) D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  17. First results on new gas mixturesforRPCs Gas mixturestested: Ar/C4H10/TP 83-3-15 withincreasing % of SF6 Preliminary Ref: B.Liberti et al, RPC2014 Beijing • TFP has a strong effect both in quenching and in keeping the charge at low level • mixtures are promising even for avalanche working mode with an appropriate FE Electronics and a dedicated chamber layout A long R&D program is needed to analyze all the proposed gases and variants First with cosmics, then at GIF Single-gap ATLAS prototype, read on the oscilloscope, averagecharge vs. efficiency D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  18. ATLAS Tor Vergata Spazio per foto e qualche riga sul laboratorio di Tor Vergata D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  19. CMS Frascati Spazio per foto e qualche riga sul laboratorio di Frascati D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  20. The Quest for Ecogascharacterizing interaction of candidate ecogases with RPC materials • Chemistry • Reactivity • Outgassing • Production of HF ? • Production of other contaminants? • Ex.: CF3I under discharge releases CF3 strong acid and corrosive • Before and after irradiation D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  21. Setup and refs for materials studies • Op4cal sensors for RPC gas • –  M.Caponero et al., Use of fiber op4c technology for rela4ve humidity monitoring in RPC detectors JINST 8 (2013) T03003 • –  S.Grassini et al., Gas monitoring in RPC by means of non-­‐invasive plasma-­‐coated POF sensors JINST 7 (2012) P12006 • –  Patent deposit ZEOSENSORS (n. RM2011A000621 24/11/2011) • •  Gas mixtures for RPC • –  S.Colafranceschi et al., A study of gas contaminants and interac4on with materials in RPC closed loop systems JINST 8 (2013) T03008 • –  S.Colafranceschi et al., Performance of the Gas Gain Monitoring system of the CMS RPC muon detector and effec4ve working point fine tuning INST 7 (2012) P12004 • –  L.Benussi et al., A New approach in modeling the response of RPC detectors Nucl.Instrum.Meth. A661 (2012) S182-­‐ S185 • –  L.Benussi et al, Study of gas purifiers for the CMS RPC detector Nucl.Instrum.Meth. A661 (2012) S241-­‐S244 • •  Materials for GEM • –  G.Saviano et al., A study of film and foil materials for the GEM detector proposed for the CMS muon system upgrade accepted by JINST (2014) D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  22. 5. Irradiation tests D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  23. Single Event Effects study on the FE boards of the improved RPC (2015-2017) • Motivations: study of radiation transient effects on the FE electronics of the iRPC • Study : cross section measurement of the transient fenomena induced by neutrons on the open input FE boards. We plan to use the following facilities: the Triga Mark II reactor in Pavia and the Louvain cyclotron. The first one covers a energy range till 18MeV which can be extended till 50MeV by the second one. • Setup : a measurement station has been already assembled and used for previous tests. The station has been instrumented with : VME crate, LVoltage PS , VME scalers, NIM crate and NIM modules, PC. • Additional costs to be addressed: • irradiation and targets for flux measurement at Triga Mark II  4kEuro • irradiation and transport costs for Louvain  7kEuro D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  24. Financial Requests (2015-2017) • Qui table D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  25. spares D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

  26. HPL: R&D relativo alla produzione di lastre di HPL a bassa resistività. Obiettivo è il raggiungimento di un valore di resistività inferiore di un ordine di grandezza rispetto a quello attualmente utilizzato (1÷6 x 1010 Ohm cm). Questo R&D è di interese comune ATLAS-CMS ma sarà seguito da CMS che ha studiato e contribuito allo sviluppo della produzione di HPL per RE4 con una nuova ditta di laminati (Puricelli) dopo la chiusura della ditta Panpla che aveva prodotto tutto l’ HPL per gli RPC degli esperimenti a LHC. La misura di resitività sarà fatta da CMS mentre il test della long term conductivity da ATLAS • Acquisto di un batch di HPL (1 batch= 80 lastre da 1.6 m x 3.2 ;) . Questo quantitativo è sufficiente per un certo numero di prototipi da 1mq per entrambi gli esperimenti e per circa 5 prototipi0 (fulls size) per ogni esperimento : 8 kEuro • Sperimentazione bassa resistività presso la ditta Puricelli : 12 kEuro (basato su circa 50 test ) • Misure di resistività: costruzione di uno strumento portatile per la misura di resistività (alimentatore,adc,elettrovalvole, consumables) 7 keuro • Test di long term conductivity sull’HPL : 3 keuto • Trasporti: le lastre saranno tagliate presso una ditta milanese e inviate alla GT per la costruzione dei prototipi: 5 keuro D.Boscherini for the ATLAS Coll. and S.Bianco for the CMS Coll. R&D RPC phase2 - Rome May 9th 2014

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