Attività di Collaborazione INFN-ENEA Esperimento CMS

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1 Risultati della ricerca del Bosone di Higgs a LHC Attività di Collaborazione INFN-ENEA Esperimento CMS S. Baccaro ENEA UTTMAT Roma 12 luglio 2012

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4 Large Hadron Collider LHC Luminosity cm -2 /s E 14 TeV Bosone di Higgs m>100 GeV H Z Z m+ m - m+ GeV m- m Z * H Z m m m g H g - 90 Higgs boson associates with Higgs field to solve the question: why elementary particles have mass and their masses are different?

5 Large Hadron Collider LHC PROTON PROTON Beam energy 7 TeV Energy at the collision = 14 TeV

6 CMS experiment H=> gg PbWO 4 (g/cm 3 ) 8.26 CMS Radiation doses (10 years) g Dose n Flux ECAL crystals Barrel <5 kgy n/cm 2 End caps 70 kgy n/cm 2 X 0 (cm) 0.89 R m (cm) 2.2 em 420 (ns) 15 n@ em 2.29 LY 2% LY temp.coeff. -2%/ C

7 CMS detector Transverse slice through CMS detector

8 ENEA- Frascati Neutron Generator ATLAS Test of a resistive plate chamber and study of the efficiency and time resolution of an RPC ALICE Measurements on the 0.25 µm CMOS pixel readout test chip

9 ENEA- TAPIRO Fast source reactor CMS Test on crystal and APD for em calorimeter

10 Dose rate ENEA Calliope 60 Co irradiation facility The Calliope plant is a pool-type irradiation facility equipped with a 60Co g source in a high volume ( m3) shielded cell. 60 Co 27 Maximum allowed activity: 3.7x10 15 Bq (100kCi) b MeV g 1.33 MeV g 60 Ni * Ni * Ni 28 Rack with 60 Co sources 1) Fricke absolute dosimetry ( Gy); 2) Alanine dosimetry (1 Gy-500 kgy); 3) Red Perspex dosimetry (5-40 kgy).

11 PC POWER SUPPLY Main Calliope features Monitoring system for water pool Biological screen windlass Internal External labyrinth system demineralising Water pool labyrinth Storage pool Co 60 source Irradiation cell Screen window Metal-clad door building access Labyrinth access Loading & unloading area mobile system Unseismic system Ozone control system Control consolle Sliding metal-clad door Control room Laboratory area Optical laboratory

12 LHCb -Racks for GEM and MWP test chambers BOTTLES MON TEST GEM PC HV Co m CONTROL ROOM

13 Collaborazione ECAL- R&D Inst. Nucl. Phys. Minsk CERN BTCP Bogoroditsk INFN Sezione Roma PbWO 4 Caltech CA-USA LUMEN BGRI-Pechino SIC-Shangai ETH Zurigo ENEA Lab. Casaccia

14 Scintillating crystal SCINTILLATOR + LIGHT DETECTOR = DETECTOR Physical processes: PMT,PD,APD Absorption I(E) = I 0 (E)e -md Conversion =bsq b eff. e -h S eff. Centres Q eff. disec. Emission Excited state h n Fundamental state Parameters Density, Emission spectrum, Light yield, Molière radius, Radiation length, Radiation hardness, Hygroscopicity.

15 Lumen Collaboration Coordinated by INFN Sez Roma Inst.Phys. Acad.Science Crytur Prague (Cezch Rep) ENEA TEC-IRR Calliope PWO -Doping -Stoichiometry -Radiation resistance -Decay Time -Light Yield -Termoluminescence Physics Dept. Univ. La Sapienza Furukawa (Japan) KEK Tsukuba Japan PWO Int. Conf. ENEA-INFN Casaccia 1998

16 Scintillating crystal parameters effectiveness & emission spectrum PM spectral sensitivity radiation length Molière radius Light Yield (LY) response time afterglow g induced colour centres can absorb photons emitted by luminescent centres. Optical transmission decrease Loss of scintillation light output hygroscopic Hardness (Moh) T t Radiation hardness Z eff n m It is necessary to investigate and optimize its radiation induced behaviour.

17 ECAL- R&D TUNGSTATO DI PIOMBO PbWO Spettri di emissione PWO2145 PWO3503 PWO3660 Cella elementare PbWO Pb Intensita (a.u.) Lunghezza d onda (nm) Fotoluminescenza-Decadimento Tempo (s) laser 400 nm 500 nm (WO 4 ) 2 - (WO 4 ) 2- centro regolare 420 nm WO 3 difetto nm Collaborazione LUMEN

18 transmission (%) induce d a bso rptio n (m -1 ) Scintillating crystal In the as grown crystal.. Radiation induced absorption coefficient by UV-visible optical absorption spectroscopy m 1 T ln 0 L T The doping of PWO with trivalent ions leads to the reduction of permanent defects Absorption ~ 350 nm => Pb 3+ ; Absorption ~ 420 nm => O - ; both created as a result of Pb 2+ vacancy. 80 In the irradiated crystal La-doped undoped und oped La-doped 295 K w avelength (nm ) wavelength (nm) Improvement of transmission optical properties and reduction of radiation damage. Irradiation induced the formation of a band around 400 nm, which reabsorbs the scintillating light.

19 Transmittance Raccolta di luce Confinamento laterale Angolo critico PWO-aria sin 1 n 26 c PWO c perdita per i c PWO 2.29 Fotorivelatore (APD) Angolo critico: Colla e finestra ad alto n involucro riflettente SiO 2 (120nm) Al (90 nm) Poly (2.5 mm) Al (foil) i c Colla 1.63 Finestra 1.57 Si PWO Si (deg) c 44 Riflessione alle interfacce: Film antiriflettente Si 3 N 4 (65nm) c

20 Growth Cutting Polishing Assembly Test Modules C R I S T A L Regional Centres activities Production centres 4 Regional Centres 1 2 Gluing Crystal- APD Acceptance Dimensions Optical properties Modules assembly China BGRI, SIC CERN Rack ACCOR Tray Barcode reader Sub modules assembly 3 3D Russia BTCP Rome Transmission LY Lamp Forwarding to CERN 5 Cern Super module assembly

21 Collaborazione INFN-ENEA costruzione Barrel Casaccia

22 Casaccia

23 Casaccia Linea di misura automatica ACCOR Controllo trasmissione Controllo 3D Cristalli pronti per il QC automatico Controllo light yield cristalli misurati

24 Casaccia Preparazione incollaggio Incollaggio in atto (24h) Controllo guadagno APD Incollaggio completato

25 Casaccia Assemblaggio sottomoduli Sottomoduli assemblati Il primo modulo! Inizio assemblaggio modulo

26 Casaccia Preparazione e posizionamento modulo nel container

27 Preparazione primo viaggio al CERN

28 Primo viaggio al CERN

29 Arrivo al CERN

30 CMS Ecal da Roma a Ginevra Marzo 2007 Festa centro regionale

31 CMS Ma non finisce qui..

32 End-cap crystals MINIACCOR LAMP INTEGRATING SPHERE Rack for crystal irradiation and measurement

33 End-cap crystals Before & after each irradiation test 2, 8, 14, 20 cm From 2 cm, 11 points at 1 cm step Measurements perform by MINIACCOR machine at Calliope Laboratories.

34 Conclusioni (o quasi) A distanza di 5 anni.. 4 luglio 2012 Risultati esperimenti ATLAS e CMS