September 7th, 2005Photon vetoes status report R. Fantechi Photon vetoes status report –WG on...

September 7th, 2005 Photon vetoes status report R. Fantechi

Photon vetoes status reportPhoton vetoes status report

– WG on photon vetoes active since November

• First meeting on December 14th

• ~2 meetings/ month during the proposal preparation

• Scope: large angle vetoes, LKr calorimeter, small angle vetoes


Large angle vetoesLarge angle vetoes

• Definition of the layout– Optimization of the layout wrt 0 detection inefficiency

• Identify distribution of energy vs angular sector• Compute 0 inefficiency with different inefficiency tables• Spot angular/energy region where a better inefficiency is

a must• Take into account LKr calorimeter and small angle vetoes

• Inefficiency quoted in the proposal:

– Between 3 10-9 and 3.3 10-8 with 8<P+<40 Gev/c and depending on the variation of the inefficiency tables wrt to realistic choices


Parametrizations of inefficienciesParametrizations of inefficiencies



– Start to think of a mechanical design• Counters in vacuum • Ways of insulating from the main vacuum• Support• Dimensions

• Simple conceptual design for the proposal• Now start to think to a detailed design

• Useful to meet together with engineers i.e. at one of the next WG meetings



– Focus on counter technology• Tiles a la CKM • Spaghetti a la KLOE

• Extensive Geant4 simulation started to study both solutions (see report from P. Valente)

– Punchtrough– Inefficiency dependence from the hitting angle,

energy and position • But also to be compared for

– Costs– Mechanical design of the support



– From now on• Do extensive simulation studies• Build and test a prototype

– Existing Kloe prototype under test (see report)– Electrons and gamma beams in Frascati

• Study electrical signal features– To define the readout electronics– To define the way of getting time and amplitude

information

• Define in detail the mechanical design

• Assign building jobs …



– Former CKM physicist interested in joining us• A lot of R/D done for CKM vetoes• A prototype (2 sectors, 80 layers, 1mm/5mm) exists at

FNAL– Tested in an electron beam. Results are published

» Inefficiency for electrons @ 1.2 Gev/c 3*10-6

– Available for inspection and tests (not easy to bring it to Europe)

• CKM private documentation open to P326– Notes on electronics/mechanics– Mechanical drawings– Photo of the prototype (useful to learn about the

mess in fiber handling)


The CKM prototype at FNALThe CKM prototype at FNAL


Examples from CKMExamples from CKM



– CKM prototype built with cast Bicron scintillator• Too expensive for the final detectors• They had plans to build in Protvino complete tiles

– Scintillator, fibers, wrapping, fiber connections, holes

– Ready to test and install– Light yield of this russian scintillator ok for them

• A prototype (1 sector, 20 layers) exists in Protvino– Made with russian scintillator– 20 layers 1mm/5mm– 20 WLS Kuraray Y-11 fibers/layer – Trapezoidal shape (28,12) 39 cm2– Total thickness 4.5 X0

– Available for transport at CERN– Could be tested in Frascati


The CKM prototype in ProtvinoThe CKM prototype in Protvino



– Protvino has the know-how for scintillator production

• They have bought all the manufacturing equipment for scintillator from Uniplast (Vladimir)

– Extruded scintillator– Molded scintillator– Intended to be used for CKM (Kplus) and KOPIO

• Interested to collaborate even for prototype studies

• Opportunity to use this facility for P326• Need discussion, inspection, agreement, control, etc..


Liquid krypton calorimeterLiquid krypton calorimeter

– Work in progress to evaluate the photon detection inefficiency of the calorimeter

• Study from Ruggiero using +0 from the special run in 2004

– Measured inefficiency <1.7*10-4 per E>12 Gev– Still not conclusive: need a factor 10

• Work started by me using +00 from 2003 and 2004 asymmetry runs

– High statistics could help

– Additional analysis possible with +0D

• Beam time will be requested in 2006– To have more statistics for +0

– Spot possible readout inefficiencies: read with NZS, exploit peak finder readout


Liquid krypton calorimeterLiquid krypton calorimeter

– Still to be done• Evaluate the effect on the inefficiency of the material in

front of the calorimeter (RICH, hodoscope, windows, etc)

– to be added to the study by Marchetto on the effect of the Stesalit plate: found to be less than 3*10-6

• Start to define the new readout electronics– CPDs are obsolete– Same functionality as the old one– Integration with the new scheme for the readout– CERN will likely take care of it


Small angle vetoesSmall angle vetoes

– Two technologies in the proposal• Shashlik (lead/scintillator) • Crystals

– Sofia/INR will build a shashlik prototype• Requests for financing in Bulgaria submitted in June• People are restarting now to work on this

– Still missing• Detailed mechanical design • Details on the readout electronics• Layout of the electrical connections for the IRCs, to

minimize the crossing of the sensitive area of the RICH and of the LKr


Test-beamTest-beam Monte Carlo Monte Carlo prototipi e fascioprototipi e fascio

Monte Carlo Monte Carlo dettagliato vetodettagliato veto

Misura di 1-Misura di 1- Stima errori sistematici Stima errori sistematici (mistag, alone del fascio, ecc.)(mistag, alone del fascio, ecc.)

Stima di 1-Stima di 1-

Monte Carlo Monte Carlo esperimento e fisicaesperimento e fisica Richieste per 1-Richieste per 1-

Validazione Validazione Monte CarloMonte Carlo

Finalizzazione Finalizzazione designdesign

Ottimizzazione Ottimizzazione design del vetodesign del veto

Costruzione/Riutilizzo prototipiCostruzione/Riutilizzo prototipi

Ottimizzazione Ottimizzazione del design del design dell’esperimentodell’esperimento

Soluzioni per il vetoSoluzioni per il veto(layout, tecnologia, readout)(layout, tecnologia, readout)

Test/caratterizzazione Test/caratterizzazione materialimateriali

Ottimizzazione Ottimizzazione costicosti


Milestones e tasks Milestones e tasks

• 31/1/2006: Definizione della tecnologia e del layout– Simulazione dettagliata dei veti Roma & Napoli & Pisa– Tools produzione MC, framework software Roma– Simulazione dei testbeam Frascati & Roma– Tools di analisi dati dei testbeam Frascati– Test a BTF di strutture esistenti Napoli & Roma & Frascati &Pisa

• 15/7/2006: Costruzione prototipo– Studi sul vuoto/degassing Napoli– Ottimizzazione readout ottico Napoli– Studio/caratterizzazione dei materiali Napoli & Roma & Frascati– Progettazione meccanica Pisa & Roma– Prototipo(i) Napoli & Roma & Frascati &Pisa

• 31/12/2006: Risultati test prototipo– Test a BTF prototipo(i) Napoli & Roma & Frascati &Pisa– Analisi dati Napoli & Roma & Frascati &Pisa

September 7th, 2005Photon vetoes status report R. Fantechi Photon vetoes status report –WG on...

Documents

Transcript of September 7th, 2005Photon vetoes status report R. Fantechi Photon vetoes status report –WG on...