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SUPERB. Separator for Unique Products of Experiments with Radioactive Beams Matt Amthor Bucknell University ReA12 Recoil Separator Workshop – July 12, 2014. Outline. Background – electromagnetic recoil mass separators SUPERB First order design Alternative operating modes
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SUPERB Separator for Unique Products of Experiments with Radioactive Beams Matt AmthorBucknell University ReA12 Recoil Separator Workshop – July 12, 2014
Outline ReA12 Recoil Separator Workshop, East Lansing • Background – electromagnetic recoil mass separators • SUPERB • First order design • Alternative operating modes • Higher order properties • Summary • Performance • Budget • Status and timeline
Goal of the recoil separator Reaction products Reaction products Separated by M/Q E,M,Q ΔQ Δφ Δθ Δp ΔE ΔM Separator Reaccelerated Beams < 108pps Additional detection Z, tracking, decay FP Unreacted beam separated by Eρ or Bρ ReA12 Recoil Separator Workshop, East Lansing • Collect reaction products • Remove unreacted beam • Disperse reaction products according to M/Q • Further identify reaction products • Energy-loss measurement (Z) • Recoil-decay tagging (characteristic decays) • …
Recoil mass separator parameters In no particular order • Mass resolving power (M/Q) • Efficiency • Angular acceptance • Energy acceptance • M/Q acceptance • Rigidity • Magnetic Br ~ p/q • Electric (if applicable) Er~ Ekin/q • Beam suppression • Physical mass dispersion • Focal plane implantation area • Drift lengths ReA12 Recoil Separator Workshop, East Lansing
Recoil separator types • Electro-magnetic mass separators • modest solid angle (~10 msr) • 1/300 mass resolution • fusion-evaporation • Large-acceptance separators • large solid angle (~80 msr) • 1/300 mass resolution • tracking • off 0 degrees or with 0-degree beam blocker • deep inelastic, induced fission • Gas-filled separators • modest to large solid angle (10-70 msr) • all charge states collected • poor mass resolution • heavy nuclei ReA12 Recoil Separator Workshop, East Lansing
Existing and planned recoil separators • Electro-magnetic mass separators • FMA (ANL) • RMS (ORNL) includes momentum achromat • EMMA (under construction TRIUMF) radioactive beams • S3 (under construction GANIL) more charge states • SUPERB (proposed for FRIB) • HIRA (new Delhi), JAERI, CAMEL (LNL) • Large acceptance separators • PRISMA (Legnaro) • VAMOS (GANIL) • … • Gas-filled separators • BGS (LBNL) • TASCA (GSI) • RITU (Jyvaaskyla) • GARIS (JAERI) • GFRS (Dubna) • TOF-separators • TOFi (Los Alamos) • ISLA (proposed for FRIB) ReA12 Recoil Separator Workshop, East Lansing
Mass resolution: dM/M~1/350 Angular acceptance: DW=8 msr(2 msr) Energy acceptance: DE/E=+/-20% M/Q acceptance: D(M/Q)/(M/Q)=10% Flight path 8.2m Max(Br)=1.1Tm Max(Er)=20MV Can be rotated off 0 degrees Can be moved along the axis Different focusing modes Argonne Fragment Mass Analyzer Q1 Q2 ED1 MD Q3 ED2 Q4 Fusion-evaporation Deep inelastic (degraders) Transfer (degraders) Used with Gammasphere ReA12 Recoil Separator Workshop, East Lansing
S3 separator – SPIRAL2 facility at GANIL qx mrad qy mrad W msr DE/E DM/M dM/M Er Br S3 50 50 8 +/-20% +/-10% 1/400 12 MV 1.5 Tm Funded, designed, under construction For experiments with high-intensity, stable beams ReA12 Recoil Separator Workshop, East Lansing
SUPERB – first order design A.M. Amthor1, A. Drouart2, Z. Jackson1, J. Nolen3, H. Savajols4, D. Seweryniak3 1Bucknell University, 2CEA-DSM/Irfu/SPhN, 3Argonne National Laboratory, 4GANIL T 3QS ED 3QS Based on the design of the mass separator section of S3 optimized for experiments with reaccelerated radioactive beams at Rea12 (smaller beam spot) 3QS MD 3QS ReA12 Recoil Separator Workshop, East Lansing FP
SUPERB – first order design Eρ~ E/q separation M/Q separation ReA12 Recoil Separator Workshop, East Lansing 4 x 3 = 12 multipoles: “M5” superimposed quad- sext- and octupole Can use S3 triplet designs directly 1 Electric dipole: “ES” with cylindrical symmetry More sizes to trade acceptance for Eρmax 1 Magnetic dipole “MS” Additional magnetic dipole to replace the electric dipole
Large Acceptance Mode Angular Acceptance in x =±43.7 mrad Energy Acceptance = ±22.3% Angular Acceptance in y =±147.6 mrad Mass Acceptance = ±17.4% Solid Angle = 25.8 msrMass Resolving power = 1600 BρMax = 2.16 Tm ReA12 Recoil Separator Workshop, East Lansing
5th order M/Q resolving power 5th order Monte Carlo with preliminary corrections 461 1228 669 928 1695 1220 1513 1920 1805 FP y (m) 28+ FP x (m) 58Ni +46Ti → 100Sn +4n 2000 particles for each of 11 charge states (9 accepted) ReA12 Recoil Separator Workshop, East Lansing
Design options ReA12 Recoil Separator Workshop, East Lansing • Second set of electrodes to increase maximum electric rigidity • Currently 10 MV (also can use a degrader) • 20 MV (trivial with reduced solid angle) • 30 MV (R&D goal) • Replace first electric dipole with magnetic dipole for a purely magnetic system for high electric rigidity experiments • Shorter distance between the target and the separator to increase the solid angle • Converging mode (after the focal plane)
Fully-magnetic optionstwo configurations • High Resolution: • QQQ-D-QQQ • High momentum resolving power (1570) • Lower angular, energy, and mass acceptance • High Acceptance: (VAMOS like) • QQQ-D • Lower momentum resolving power (1001) • Very high angular, energy, and mass acceptance ReA12 Recoil Separator Workshop, East Lansing
High acceptance optionVAMOS-like E and Bρacceptance depends on the size of the focal plane. Angular Acceptance in x =±45.2 mrad Magnetic Angle = 18.23° Angular Acceptance in y =±150.0 mrad Bρmax= 2.12 Tm Solid Angle = 27.1 msr Momentum Resolving power = 1001 ReA12 Recoil Separator Workshop, East Lansing
High resolution option Angular Acceptance in x =±53.4 mrad Energy Acceptance = 44.9% Angular Acceptance in y =±59.1 mrad Bρmax= 1.92 Tm Solid Angle = 12.6 msr Momentum Resolving power = 1570 ReA12 Recoil Separator Workshop, East Lansing
Flexibility – solid angles / Bρmax ReA12 Recoil Separator Workshop, East Lansing Reduced initial and final drifts allow solid angles above 60 mSr Bρmax drops to 1.3 Tm Small drifts wouldn’t accommodate large detectors around the target
SUPERB summary ReA12 Recoil Separator Workshop, East Lansing • State-of-the-art, flexible EM mass separator [comparison to FMA] • Large distance between target and separator: 0.9 m [3x] • Large solid angle: 26+ msr [3x] • Large M/Q acceptance: +/-15 % [3x] • better mass resolution: up to 1900 [5x] • Cost: approximately $7.2M • Including equipment, installation, swinger, extra dipole,contingency… • Time schedule • 1 year - design • 2 years - manufacturing of optical elements • 1 year - construction • To do list • Detailed optics calculations (already started) • Simulate degrader or narrower e-dipole for high Eρ • Additional modes and configurations…
Thank you ReA12 Recoil Separator Workshop, East Lansing