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Status of the Calorimeter Working group activities. GSI, 16 th October 2007. NUSTAR CALORIMETER Working Group. Coordinator : D. Cortina R3B (D.Cortina) / EXL (J.A. Scarpaci) Created in : February 2005 after the NUSTAR collaboration
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Status of the Calorimeter Working group activities GSI, 16th October 2007
NUSTAR CALORIMETER Working Group Coordinator : D. Cortina R3B (D.Cortina) / EXL (J.A. Scarpaci) Created in : February 2005 after the NUSTAR collaboration Goal: Find synergies between the different calorimeters in NUSTAR (R&D, Desing phase, but also common front to negociate with providers) List : 41 members, 21 Institutions , 10 countries, Meetings - February 2005 GSI, Darmstadt (Germany) - June 2005 Valencia (Spain) - Informal meeting , September 2005, Orsay (France) - September 2005 Santiago de Compostela(Spain) - February 2006, IPN Orsay (France) - September 2006, Krakow ( SPIRAL) *
Last year activities • R3B/EXL collaboration working group, Milan October 2006 • CWG meeting, Nustar week, GSI March 2007 • Prototype definition videoconference, May 2007 • CWG meeting, Lund June 2007 • Working progress videoconference, September 2007 • CWG meeting, GSI October 2007 www.usc.es/genp/r3b calorimeter
Technical Proposal (2005) Large dynamical range for detecting p,g Inner radius ~ 30 cm ( house Si trackers) UHV compatible for EXL Affordable cost!!!
Experimental constraints ECM = 10 MeV Gammas are emitted with energies up to Elab= 3.2 ECM (for β = 0.82 ~ 700 A. MeV) • A huge crystal length is required for full energy absorption (β = 0.82) The angular distribution of the emitted gammas is peaked in the forward direction. • allows a certain optimization of the angular coverage The forward angular region will be the most delicate part
Calorimeter sectors Angular distribution Doppler shift BARREL ECM = 10 MeV β = 0.82 FORWARD ENDCUP
R&D working group activities • General design studies (R3B) barrel: IPNO,USC forward endcup: IPNO,USC • R&D on Crystals and photosensors barrel: IPNO,USC, Lund forward endcup: Madrid • Simulations (R3B) full calorimeter : USC partial : Lund, Madrid
R&D working group activities • Mechanical structure cell structure: IPNO,USC, TU-Vigo general mechanical support NN • Prototypes barrel: IPNO,USC, Lund forward endcup: Madrid • Electronics NN • Slow control and monitorisation NN
General design: R3B Calorimeter models (CAD) v1.2 v4.0a v4.0c v4.0b USC, IPN
General design: R3B Calorimeter models (CAD) v5.0 Last accepted version for the barrel design Inner radius 30 cm Few crystal shapes Garantees DE/E~ 3% (due to polar angular resolution) H. Alvarez, USC
R3B Calorimeter Target x 2.2T Magnet Beam axis 14° z 1450mm (0,0,0) Crystal and photosensors • BARREL • CsI(Tl) + PM IPNO ~300 Gauss at PM level PROBLEM Good energy resolution Shielding needed to work with PM
Crystal and photosensors CsI(Tl) + LAAPD USC Very good energy resolution Variation of APD gain with temperature monitorization needed
Crystal and photosensors CsI(Tl) + PD LunD Moderate energy resolution Very high threshold problem to register low energy gammas
Crystal and photosensors CsI(Tl) + PD LunD Uppsala, TSL, GWC, B-line (Blue hall): Energy 179.31±0.80 MeV. excelent energy resolution for 180 MeV protons Huge contribution of nuclear interactions and multiple scattering
Crystal and photosensors • Forward endcap • LaBr + PM not yet investigated • Two layer detectors IEM, Chalmers Ë=f(D E1 )+ g(D E2) E D E1 D E2 LaBr3(Ce) of 30 mm LaCl3(Ce) of 150 mm the estimated final energy is proportional to the energy deposited in each layer need to be proven from measurements and simulations M.Turrion, O.Tengblad IEM
Calorimeter models (GEANT4) Detailed simulations v1.2 v4.0a v4.0b Allowed very valuable information - geometry efficiency and granularity - tracking algorithm tests etc etc…. H.Alvarez USC
Barrel Prototypes CsI(Tl) + LAAPD Hamamatsu 2x S8664-1010
Materials • Realistic frustum-shaped crystals: • Lanzhou • Hilger • St. Gobain (France and India) • Scionix • LAAPDs Hamamatsu • 2x(10x10) mm2
Barrel Prototypes Square PMT Photonis (1 per 2 crystals) Rectangular Crystals
Barrel Prototypes In 2008, construction of a prototype of 18 Xtals [CsI(Tl)] with 9 square PMT • Simulation and Tests of the prototype with different thickness of material in between the crystals depending on mechanical and physics considerations.
Time schedule (R3B) Infofrom 2006 extension of ~ 1 years
Conclusions • Good way towards the definition of the barrel design CsI(Tl) + PM /LAAPD First detectors (realistic size) will be mounted next weeks Prototypes ready around summer 2008 Different facilities are considered to perform in beam test with these prototypes • Detection in forward sector is still a real challenge We need to investigate in detail the proposed solutions and/or find alternatives Urgent to address this problem within next year • Technical man power is needed mechanical structure electronics and slow-control is not yet addressed • We are lacking the support of big laboratories Not yet urgent today but mandatory for the construction phase