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EXotic nuclei studied in Light-ion induced reactions at the NESR storage ring Key physics issues • Matter distributions (halo, skin…) • Single-particle structure evolution (magic numbers, shell gaps, spectroscopic factors) • NN correlations, clusters CR RESR NESR Light-ion scattering Elastic (p,p), (a,a) … • New collective modes (different deformations for p and n, giant resonances strengths) Inelastic (p,p’), (a,a’) ... • Astrophysical r and rp processes (GT, capture…) Quasi-free (p,pn), (p,2p), (p,pa) … • In-medium interactions in asymmetric and low-density matter Charge exchange (p,n), (3He,t), (d,2He) … Transfer (p,t), (p,3He), (p,d), (d,p) … ~ 10 … ~ 740 MeV/nucleon Collector Ring Bunch rotation Fast stochastic cooling RIB (740 MeV/nucleon) NESR Electron cooling Experiments RESR Deceleration (1T/s) to 100 - 400 MeV/nucleon Later stage of FAIR EXL Set-up – Concept and Design Goals Design goals • Universality: applicable to a wide class of reactions • High energy and angular resolution • Fully exclusive kinematical measurements • High luminosity (> 1028 cm-2 s-1) • Large solid angle acceptance • UHV compatibility (in part) Internal gas-jet target (>1014 cm-2) Detection systems for: • Target recoils (p,a,n,g…) • Forward ejectiles (p,n,g) • Heavy fragments Big R&D effort needed! Phase I EXL EXL Gamma & Particle Array Recoil & Gamma Array EXL Silicon Particle Array Phase II Challenging requirements: • High efficiency and universality • High angular and energy resolutions • Low threshold • Large dynamic range • High granularity • Vacuum compatibility •… Choice of detector types for the baseline scenario of the EXL Recoil & Gamma Array Energy – Position – Identification Si DSSD 300 mm thick, spatial resolution better than 500 mm in x and y, DE 30 keV (FWHM). Mass & charge identification Thin Si DSSD <100 mm thick, spatial resolution better than 100 mm in x and y, DE 30 keV (FWHM). Lower thresholds Mass identification Si(Li) 9 mm thick, large area 100x100 mm2, DE 50 keV (FWHM). CsI crystals High efficiency, high resolution, 20 cm thick. Synergy with R3B & NUSTAR. Design study • Thin DSSD • PSD with DSSD • Integrated devices DE-E monolitic • MAPS • Si(Li) • CsI and other crystals • Vacuum chamber Characteristics of EGPA (EXL Particle and Gamma Array) • • • • • • • Detect both gs and charged particles Gamma sum energy, m and individual energies 95% 4P coverage, e=80% for Eg= 2-4 MeV Stopping 300 MeV protons DE = 2-3% for gs and 1% for fast protons Bins in polar angle of 1o-4o for Doppler Correction Total of about 1500 crystals of 20 cm in length 2 Phases : 1.7 + 0.6 M€ if CsI The MUST2 Array •Compact and efficient: bound and unbound states • g-particle coincidences •Examples : (a,6Be) with cryogenic target 2-nucleon transfer for pairing studies 2-proton decay measurements IPNO-GANIL-SACLAY collaboration MATE for Si, Si(Li) & CsI HT 16 ch PA wide band +/-ve Amp Slow Amp Fast Multiplex Disc LE Track Hold TAC 6 mm MATE PULSER MUFEE Slow Control Gain, Disc .. Stop M U L T I P L E X E R MATE - Performance 6 mm • 16 Channels (Fast & Slow) – Bipolar (slow & fast) – Slow Control – Energy (Track & Hold) • 1µs/3µs RC-CR • 0.3 - 50/250MeV (1:800) • 25/90 KeV – Time What is New ? - In Nuc. Phys. Env. new - Dynamic Range 1:800 new - Time & Energy new And it’s functioning ! • Disc Leading Edge • TAC (300nsec) • 240 psec jitter • Chip 36mm² – BCMOS 0.8 µ – 16000 transistors – 35 mWatt/channel • Serial output 2 MHz R&D Detection Group http://ipnweb.in2p3.fr/~rdd Head : Joel Pouthas 5 Engineers 3 Technicians (Mechanics) 2 Technicians (Electronics) 4 Technicians (Assembling Detectors) 1 Secretary (part time) Gaseous Detectors Wire Chambers, MPGD ALICE @ CERN HADES @ GSI Scintillators Photomultipliers G0 & DVCS @ Jefferson Lab P.AUGER Observatory 3 Clean Rooms 3D measuring Machine Jefferson Lab.@ Newport News Mechanics DVCS / CLAS Inner calorimeter (PbWO4) 424 crystals, 160 mm long, APD readout PROTOTYPE 100 Crystals 2002 R&D 2003 Construction of a prototype 2004 (Jan) Prototype test on beam 2004 Final design and construction 2005 (Mar) Experiment Jefferson Lab.@ Newport News DVCS / CLAS Geant 4 simulation Simulation Electromagnetic Shower 2 GeV electron Jefferson Lab.@ Newport News DVCS / CLAS GSI @ Darmsdat PANDA / EM Calorimeter Studies Mechanics Thermal Integration Simulations Geant 4 R&D Prototypes Beginning of studies September 2004 GSI @ Darmsdat PANDA / EM Calorimeter Carbon Cells GSI @ Darmsdat EXL A Few Questions to Address • Do we need 2 calorimeters for EXL and R3B? • Why does the EXL calorimeter have 1500 modules and the R3B 10000? • Do we need sum energy for EXL applications? (i.e how important is 4P coverage?) • Is CsI the best material? (see Jürgen Gerl’s talk). Do we need cooling? • Will APDs give sufficient dynamic range, or do we need PMTs? • Does EGPA need vacuum? • …. How can we (IPNO) help answer • Produce a first complete realistic mechanical design. Engineering time will be available starting october. • Do detailed Géant 4 simulations of some specific experimental situations (A post doc, Flore Skaza, has been hired for one year and will start in sept.) • Do studies on materials? • We are willing to contribute to both EXL and R3B. • We need to co-ordinate with other groups and labs.