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S 3 : Super Separator Spectrometer. Spiral 2 Physics objectives Optics Construction status Phase 1++. S 3 Collaboration ( LoI signed by 28 laboratoires)
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S3 : Super Separator Spectrometer Spiral 2 Physics objectives Optics Construction status Phase 1++ S3 Collaboration (LoIsigned by 28 laboratoires) ANL (US), CENBG, CSNSM, JINR-FLNR, (Russia), GANIL, France, GSI (Germany), INFN Legnaro, (Italy), IPHC, France, IPNL, , Irfu CEA Saclay, IPNO, France, JYFL (Finland), K.U. Leuven (Belgium), Liverpool-U, (UK), LNS (Italy), LPSC, MSU (US), LMU, (Germany), Nanjing-U (China), Northern Illinois University(US), SAS Bratislava, (Slovaquia), IFJ PAN Cracow (Poland), SmoluchowskiInstitute (Poland), CEA-DAM; SUBATECH, TAMU(US), U. Mainz (Germany), York-U (UK), Vinca Institute(Serbia) INP
S3 in the Spiral2@Ganil project Present Ganil Fed by the very high intensity stable heavy ion beams of LINAG - He to U nuclei - From 2 to 14MeV/u Desir Spiral2 Phase 1++ (2015) S3 Goal: Study of very rare events in nuclear and atomic physics NfS
LoIPhysics objectives FISIC project LoI_Day1_1 Collaboration meeting March 2014 Number of participants : 100 12 LoIs updated + 3 new proposals Fusion-evaporation Heavy and Superheavy Elements • Spectroscopyand Structure • Reactionmechanism • Ground-State Properties • Synthesis Proton Dripline & N=Z nuclei • Tests of Shell Model • Shapes of nuclei • Exoticdecay • Ground-State Properties Neutron-RichNuclei • LoI_Day1_7 • Single-Particle structure • Quenching of Shell Gaps Delayed spectroscopy (SIRIUS) : 4 loIs GS properties measurements (REGLIS3) : 6 LoIs In beam spectroscopy (PARIS,EXOGAM, …) : 4 LoIs Atomic physics (FISIC) : 1 LoI
Experimental Techniques • Converging mode • Gas catcher+ Laser ionisation + Mass Resolution by Time-of-flight • β/β–delayed • Laser spectroscopy • High resolution Mass measurement • Chemistry • Final focal plane • Selection & Identification • Time of flight + Energy • A measurement Beam Multi-purpose Experimental Room • Achromatic point • Two step reactions • Transfer+Fusion (transfer) • Specific Modes • Ion-ion collision : FISIC Program • Mass dispersive mode • Delayed spectroscopy • p, α, γ, e- decay DESIR
Optics J. Payet, D. Uriot (SACM) D. Boutin, F. Dechery (IPHC) * 1st Selection : block 99.9% of the beam Target Achromatic Focal point Final focal plane** Beam dump* Momentum Dispersive plane A=101,100,99 Horizontal 300 mm Mass spectrometer Momentum Achromat 22+ 23+ 24+ 25+ 26+ 300 mm **2nd selection: Simulated Mass resolution = 460 Vertical Tracewin simulations : Full raytracing in the multipole 3D field maps Automatic optimisation of 70 field values Under process: implementation of 3D field maps of the magnetic and electric dipoles
Operational modes and Performances Reference reaction : 58Ni + 46Ti 100Sn24++ 4n σ(E) = 1.7% σ(θ) = 20mrad Close Target Position 3) Converging 1) High resolution 2) High transmission φ=5cm 1) 2) 3)
Technical Highlights 3 × dipoles Dispersive zone Open triplet Construction by Sigmaphi LowEnergyBranch Fingers : tested for 5kW/cm2 Delivery: March 2013 Detection system Target system Prototype tested in 2012 7 × SC multipoles Q+S+O fields Prototype of 1st coil Tested E dipole
Phase 1++ • Very high intensity beams with: • Phoenix V3 source Superconducting ion source • A/q=3 RFQ Low charge state injector A/q=6 • Rate summary vsGSI UNILAC • 2-4 [A/Q=3, Phoenix V3] • 15-20 [A/Q=6, SC source]
Conclusions • S3 is a low energy separator-spectrometer for the Spiral2 stable beams • Fusion-evaporation, two-step reactions, rare channels, electron exchange… • High versatility • High energy mode (up to 1.8Tm) • Various optical modes: high resolution, high transmission, converging • Designed for the selection and identification of rare events • 2 steps rejection and >300 Mass resolution • High transmission of evaporation residues • Construction phase has started • Commisionning in 2016 • Phase 1++ to reach full power
S3 room, one week ago Thank you for your attention!
Very and Superheavy elements studies • Nuclear structure • Quasi-particle excitations deformation/K-isomers • Alpha/gamma/electron spectroscopy • X ray spectroscopy • Reaction studies • Isospin dependent investigation Instrumentation SIRIUS setup Z > 112 Actinide targets 48Ca beam and heavier
BeamDump (O. Cloué, SIS) Stopping 99.9% of the primarybeam charge states Shielded removable “plugs” Upstream Beam dump Design by F. Nizery (SIS) Downstream Beam Dump Open magnets quadrupole+sextupole Under construction by Sigmaphi (O. Delferrière, J. Payet SACM)
Technical Challenges • High Beam intensity • High power target : 10pµA (= 6.1013p/s) or more • Rejection of the beam : >1013 • Low Energy (fusion-evaporation residues) • Large angular acceptance : +/- 50 mrad X and Y • Charge state acceptance of +/- 10% (q=20+) • Momentum acceptance for each charge state Bρ: +/- 10% • Many reaction channels (evaporation channels) • M/q selection : 1/300 (FWHM) resolution • Identification when possible • Versatility (transfer reactions & atomic physics) • High energy first stage : Bρmax = 1.8Tm • Secondary reactions
New : implementation of 3D electricdipolefieldmap 2cm high slit to reduce scattering
Day 1 SPIRAL2 LINAC beams Energy = 0.75-15 A.MeV Gases 18O6+ 36Ar12+ Beam Intensity Reached 58Ni19+ Phoenix V2 : 4He2+: 850 pµA 18O6+ (from16O16+): 216 pµA 19F7+ : 28,6 pµA 36Ar12+: 17.5 pµA 40Ar14+: 2.9 pµA 32S11+: 7.3 pµA (not opt.) 36S12+ (from32S12+): 4.6 pµA 40Ca14+: 3 pµA 48Ca16+ (from40Ca16+): 1.25 pµA 58Ni19+: 1.1 pµA Phoenix V3 (Apr. 2014) 50-100% Int. increase Beam developments Improvement Ca,Ni, S Development Si,Ti,Cr PHASE1+ scientific programs require at middle term very high Intensity HI beams (>10 pμA for A>50) Development of a new SC ECR Ion Source New RFQ A/Q=6-7
SIRIUS (Spectroscopy & Indentification of Rare Ions Using S3) Germanium detector e.x. Exogam2, CLODETTE Implantation detector (HI, and e- decay) Time of flight + trackingdetector Tunnel detector for escaped e- and • Large size (200x150 mm2) • Time Resolution < 1ns • Position resolution = 1mm • Verylowthickness • Large detector size 10x10cm2 • High resolution FWHM • Ability to detect large> 50MeV pulse • Followed(≈ 10µs) • by a weak (<15MeV) pulse. • No Dead time • Conversion electrons FWHM <5 keV • Escaped alpha FWHM 15 keV R&D is ending Construction phase could start Search for the funds !
LowEnergyBranch Gascellchamber 10-2 mbar (LEUVEN, GANIL, IPNO, LPC…) électrode extraction HRS RFQ 90o RFQ extraction Identification Station 500 mbar Cellulegazeuse DESIR Faisceau laser 10-5 mbar S3 Pure Beam Expected performances HRS or MRTOF cocktail beam
Basic Detection set-ups Gascellchamber 10-2 mbar (LEUVEN, GANIL, IPNO, LPC…) Lowenergybranch extraction HRS HRS RFQ 90o RFQ extraction Identification Station Implantation-decay station (CSNSM, Ganil, IPHC, Irfu) DESIR 500 mbar 10-5 mbar LASER BEAM S3 Pure Beam HRS or MRTOF • Emissive foils : Time of flight and tracking • Silion box : • Energy • Decaycorrelation • α, p, e- spectroscopy • Ge detectors : gamma spectroscopy cocktail beam
58Ni + 46Ti 100Sn + 4n Simulations by F. Déchery (PhDthesis) Eρ of evaporationresidues, target and beam (second stage selection) Bρ of evaporationresidues, target and beam (first stage selection) XY image at the beam dump