ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré1 Work at IPN Orsay R&D on Calorimeters Jean Peyré Dec 2007

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré2 1: R&D Status at IPNO Prototypes for Calorimeter Dual Square PMTs (1 per 2 crystals) received from Photonis (3 PMT 9 stages) CsI(Tl) Crystals received from Scionnix

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré3 1: Xtals received from Scionnix Frustum Crystals #2 have been send back to Scionnix for non conformity Reference Crystals #1 are kept for Xtalk tests Crystal #1 Crystal #2

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré4 1: Xtals ordered from other manufacturers New crystals ordered :- Amcrys (Russia) and SICCAS (China) Standard crystal 110mm long and lengthened crystal 140mm long to be able to protect PMT against Magnetic field with  metal

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré5 1: PMT’s 3 PMT’s -1 with window thickness 3mm -1 with window thickness 2mm -1 with window thickness 3mm + saw line 3mm 2mm 3mm +saw line saw line

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré6 1: PMT’s- measure of Crosstalk We want to measure the Crosstalk between the two channels of the PMT when placing a crystal in front of one of the two channels. Case A S1 a =G1*NbPhé1 a S2 a =G2*NbPhé2 a Case B S1 b =G1*NbPhé1 b S2 b =G2*NbPhé2 b Cross-Talk CH1->CH2 NbPhé2 a /NbPhé1 a =S2 a /S1 a* G1/G2 CH1 CH2 CH1 CH2 Cross-Talk CH2->CH1 NbPhé1 b /NbPhé2 b =S1 b /S2 b* G2/G1 NbPhé= Number of Photoélectrons created on each part of the photocathode & collected by first dynode G= global Gain for each Channel (PMT+ChargePream+Shaper) S= signal for each channel CH

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré7 1: PMT’s- measure of Crosstalk Cross-Talk = (S1 b /S2 b* S2 a /S1 a ) 1/2 Cross-Talk CH2->CH1 Cross-Talk CH1->CH2 Are supposed equal (estimation of ± 12% variation between both) Window 3mmWindow 2mmWindow 3mm+saw line Xtalk18.88%7.95%5.83% Xtalk23.69% Xtalk1= standard Crosstalk Xtalk2= standard Crosstalk measured with a black foil inserted in the saw line The standard production of PMT will certainly provide a quite constant crosstalk between channels: easy to correct

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré8 2: Study of thin envelops for LaBr3 Xtals with Saint-Gobain LaBr3 with Standard package (thickness 2mm) LaBr3 with Aluminium+Carbon package (thickness < 0,3 mm) R% =2.9% R% =3.3% 17x17x6mm diam25x25mm

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré9 3: Magnetic field R3B Magnetic field along Z m axis of Magnet 600 Gauss (0,0,0) m ZmZm XmXm Beam axis 14° Target 1450mm R3B Calorimeter 2.2T Magnet YmYm ZcZc YcYc XcXc (0,0,0) m ZmZm YmYm Beam axis 2.2T Magnet XmXm ZCZC YCYC XCXC R3B Calorimeter Discussion with J.E. Ducret from CEA Saclay on September 24 th, 2007

ipno.in2p3.fr Orsay - December 2007IPNO-RDD-Jean Peyré10 3: Magnetic field R3B (0,0,0) m ZmZm XmXm Beam axis 14° Target 1450mm R3B Calorimeter 2.2T Magnet YmYm ZcZc YcYc XcXc Iron wall 2m*2m*10cm News from J.E. Ducret December 2007: simulation of an iron cylinder around the calorimeter with a clearance of 10 cm around the barrel. iron wall seems not so easy to implement between calorimeter and magnet. New meeting with J.E. Ducret on October 31 th 2007 People from Saclay are going to simulate the addition of a 2m*2m*10cm iron wall to protect the calorimeter from magnetic field Iron cylinder