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CR RESR. NESR. EX otic nuclei studied in L ight-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
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CR RESR NESR 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 • New collective modes (different • deformations for p and n, giant • resonances strengths) • Astrophysical r and rp processes • (GT, capture…) • In-medium interactions in asymmetric • and low-density matter • Light-ion scattering • Elastic (p,p), (a,a) … • Inelastic (p,p’), (a,a’) ... • Charge exchange (p,n), (3He,t), (d,2He) … • Quasi-free (p,pn), (p,2p), (p,pa) … • Transfer (p,t), (p,3He), (p,d), (d,p) … ~ 10 … ~ 740 MeV/nucleon
RIB (740 MeV/nucleon) Collector Ring Bunch rotation Fast stochastic cooling 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 Phase II EXL Recoil & Gamma Array EXL Gamma & Particle Array EXL Silicon Particle Array • 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). • Thin Si DSSD • <100 mm thick, spatial resolution • better than 100 mm in x and y, • DE 30 keV (FWHM). • Si(Li) • 9 mm thick, large area 100x100 mm2, • DE 50 keV (FWHM). • CsI crystals • High efficiency, high resolution, 20 cm • thick. Mass & charge identification Lower thresholds Mass identification • Design study • Thin DSSD • PSD with DSSD • Integrated devices DE-E monolitic • MAPS • Si(Li) • CsI and other crystals • Vacuum chamber Synergy with R3B & NUSTAR.
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
6 mm MATE for Si, Si(Li) & CsI HT 16 ch Amp Slow M U L T I P L E X E R Track Hold PA wide band +/-ve Amp Fast TAC Multiplex Disc LE MATE Slow Control Gain, Disc .. Stop PULSER MUFEE
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 • Disc Leading Edge • TAC (300nsec) • 240 psec jitter • Chip 36mm² • BCMOS 0.8 µ • 16000 transistors • 35 mWatt/channel • Serial output 2 MHz What is New ? - In Nuc. Phys. Env. new - Dynamic Range 1:800 new - Time & Energy new And it’s functioning !
3 Clean Rooms 3D measuring Machine 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
Mechanics Jefferson Lab.@ Newport News DVCS / CLAS Inner calorimeter (PbWO4) 424 crystals, 160 mm long, APD readout 2002 R&D 2003 Construction of a prototype 2004 (Jan) Prototype test on beam 2004 Final design and construction 2005 (Mar) Experiment PROTOTYPE 100 Crystals
Jefferson Lab.@ Newport News DVCS / CLAS Geant 4 simulation Simulation Electromagnetic Shower 2 GeV electron
GSI @ Darmsdat PANDA / EMCalorimeter Studies Mechanics Thermal Integration Simulations Geant 4 R&D Prototypes Beginning of studies September 2004
GSI @ Darmsdat PANDA / EMCalorimeter Carbon Cells
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.