Update su sistema distribuzione laser: pannello del calorimetro C.Ferrari, A.Fioretti, C.Gabbanini, G.Venanzoni INO, UOS Pisa, Via G. Moruzzi 1, Pisa LNF, INFN Frascati

f DAQ, Slow Control laser1 laser2 laser3 laser4 laser5 laser6 Laser control Source Monitor Fiber collimator Laser hub Diffuser Calorimeter Local Monitor X 24 T80/R20 50/50 filter wheel PANEL Fibre lancio al centro ring – stazioni calorimetriche Sistema distribuzione laser

Impulso laser dopo fibra lancio 25 mt step-index silica fiber 1.5 ns attesi 0.8 ns osservato

Diffusore sphere no lens with lens no lens Engineered diffuser ED1-S20 by RPC Photonics – Thorlabs

Stability of distribution system (a few pJ/pulse at the PINs) Laser launching fiber (  600  m) Fibers PMMA 1mm diffuser PIN2+CREMAT PIN1+CREMAT CAEN DT5730B systematics ~ /h

Light sealed diffuser Silica launching fiber Diffuser enclosure POF bundle

Diffusore + bundle

+/- 5V Bias x 4 Comm HDMI breakout Air below Calorimeter and rack mounting (adapted from Dave, top view) Launching fiber (SMA connector) Laser diffuser (in light sealed tube) POF bundle (64 fibers) Light distribution panel Rigid aluminium/plastic enclosure For bundle and diffuser Local monitoring (PMT)

PMMA fiber Prism PbF 2 crystal SiPM Panello 1° prototipo PVC

2° prototipo in Delrin 1x9

Output power from panel n.fibra Red: output from fiber Blue: output after coupling Green: ratio blue/red Fibre 1 mm PMMA Prismi 8 mm senza a.r. coating

Output power from two fibers

Light distribution out of crystal Fiber 1mm PMMA NA=0.49 Disomogeneity 3% on 12 mm 1D

Distribution system transmission: 6 lasers/ 24 diffusers Required value of the output of each crystal: 0.01 pJ/pulse (el. 2GeV); for each calorimeter: 0.6 pJ/pulse Element Transmiss ion Energy (pJ) Notes Laser Picoquant output750100% current intensity Source monitor sampling80% pJ/pulse for the source monitor (2 PD and 1 PMT) Filter wheel100%600 Division into four fibers 25% 150 Fiber coupling + 25 mt quartz fiber 70% 105Measured Diffuser with bundle (54 fibers) + 3 local monitors 10%10.5 It can increased by reducing uniformity 1 mt bundle POF (200 dB/km) 90%9.5 Prism coupling 65% 6.1 Prism with anti-reflection coating and with metallized reflecting face PbF 2 crystal reflection + absorption (20%) 65% 4.0 Total per calorimeter4.0Required: 0.6 pJ /pulse /calorimeter Not included: Beam splitting losses (mirrors, b.s.) Counter-panel losses

Acquisti distribuzione 28 K€ anticipo 2015: Prismi 7 K€ 24 diffusori 10 K€ Delrin x pannelli 1 K€ Spool fibra + 1 bundle 5 K€ Elementi x splitting 5 K€ Nel 2016: Bundles Fibre di lancio Lasers & Splitting rimanente

Conclusioni Il sistema di distribuzione laser è ben definito Prototipo di pannello testato; pannello completo in delrin (6x9) in costruzione a breve (officina INFN-PI grazie a F.Bedeschi) Sistema a 6 laser / 3 laser da definire dopo il test beam a SLAC Primi ordini per costruzione apparato ad ottobre

SPARES

Calo version... 1) December 2016 milestones (can be earlier) UW builds complete module carries out local tests for cooling, system performance, etc. Naples sends a Flight Simulator to Seattle for us to begin incorporating it into our light flashing system. UVa/JMU has provided commercial bias supplies for a full calorimeter (4) and the +/-5V distribution. Also provides needed cabling Cornell and Kentucky have completed tests at Fermilab of digitizers and DAQ "Offline" tools available to reconstruct pulses, make histograms, etc. 2) January Week 1. Pisa team has delivered completed Front Panel, Bundle, Light Distributor, Laser and Splitters. 3) Februrary Week 1. Cornell delivers crate of Riders Week 1. Kentucky delivers DAQ.and associated bundle, laser, etc, to drive. Someone (Wes?) needs to be in Seattle for a week of shakedown and expertise transfer. This month used for running with Flight Simulator and for writing analysis and diagnostic codes. 3) March. Week Buffer for any delays Week 4. Packing for shipment to SLAC. 4) April TEST BEAM TIME AT SLAC Week 1. Arrive SLAC; Build installation Week 2. Tracker tests day; Calo test night Week 3 Calo tests day; Tracker night Week 4 Combined data taking 5) May Analysis 6) June 1st. Calo kits shipped to FNAL to begin assemble All Laser Front Panel kits also arrived FNAL for assemble... etc Professor David Hertzog University of Washington Department of Physics Box Seattle, WA (206)

Transmission coefficient- diffuser Inhomogeneity strictly connected with transmission coeff. Measurements with/without collimating lens changing the distance diffuser-bundle or lens/bundle

Transmission coefficient- diffuser Inhomogeneity strictly connected with transmission coeff. Best results: without lens 5.7% in a bundle group T= (new with square pattern diffuser: 4%) with lens 7% in a bundle group T= sphere no lens with lens

Diffuser no lens with lens 2% inhomog. on 0.2 mm in the central zone