1. Design and Development of a Trochoidal Mass Separator at the Berkeley Gas-filled Separator J.M. Gates, K.E. Gregorich, G.K. Pang, N.E. Esker and H. Nitsche Lawrence Berkeley National Laboratory 11 th International Conference on Nucleus-Nucleus Collisions May 29, 2012 San Antonio, TX

2. Outline Region of Interest Berkeley Gas-filled Separator Trochoidal Mass Separator

3. 118 117 116 288 115 88 ms 287 115 32 ms 115 114 282 113 61 ms 284 113 0.48 s 283 113 0.10 s 278 113 2 ms 113 277 112 0.7  s 112 278 111 4 ms 280 111 3.59 s 279 111 0.17 s 274 111 15 ms 272 111 3 ms 111 269 110 130  s 110 270 110 3 ms 271 110 12 ms 273 110 170  s 276 109 0.72 s 275 109 10 ms 274 109 2.91 s 266 109 2 ms 109 268 109 25 ms 270 109 3 ms 269 108 14 s 268 108 0.37 s 267 108 68 ms 266 108 4 ms 265 108 2 ms 263 108 23 ms 262 108 260  s 108 270 108 23 s 262 107 0.10 s 261 107 12 ms 260 107 32 ms 107 266 107 1 s 265 107 0.94 s 264 107 0.11 s 267 107 17 s 270 107 61 s 272 107 9.79 s 106 259 106 0.48 s 261 106 0.23 s 263 106 0.9 s 265 106 21 s 264 106 37 ms 262 106 21 ms 260 106 3.6 ms 259 105 0.5 s 258 105 4.4 s 105 260 105 1.5 s 261 105 1.8 s 262 105 34 s 263 105 27 s 267 105 73.4 h 268 105 15.9 h 266 105 22 m 267 104 77 m 258 104 12 ms 257 104 4.0 s 104 259 104 3.0 s 260 104 21 ms 261 104 2 s, 78 s 285 114 0.12 s 281 112 97 ms 277 110 5.7 ms 273 108 0.25 s 269 106 130 s 265 104 105 s 277 108 3 ms 103 256 103 28 s 255 102 3.1 m 254 101 10 m 255 101 27 m 256 101 78 m 257 101 5.52 h 253 100 3 d 256 100 158 m 259 102 58 m 260 103 180 s 259 103 6.3 s 258 102 1.2 ms 257 103 0.65 s 258 103 3.9 s 256 102 2.91 s 257 102 25 s 102 101 100 254 100 3.2 h 255 100 20 h 257 100 100 d 258 101 51.5 d 261 103 39 m 262 103 216 m 260 102 0.11 s 259 101 96 m 258 100 370  s 259 100 1.5 s 260 101 31.8 d 290 116 14 ms 271 108 4 s 263 104 8 s 294 118 1 ms 293 116 53 ms 292 116 18 ms 291 116 18 ms 287 114 0.45 s 289 114 2.70 s 288 114 0.80 s 286 114 0.12 s 282 112 0.8 ms 284 112 0.10 s 283 112 3.83 s 285 112 33.5 s 275 108 0.19 s 271 106 114 s 281 110 9.6 s 279 110 0.20 s 266 106 0.32 s 267 106 84 s 293 117 14 ms 289 115 0.22 s 285 113 5.5 s 281 111 26 s 294 117 78 ms 290 115 16 ms 286 113 20 s 282 111 0.51 s 278 109 7.7 s 274 107 0.9 m 270 105 23 h 262 104 0.19 s

5. Berkeley Gas-filled Separator (BGS)

6. Positive: High efficiency Large suppression of beam and unwanted reaction products

7. Berkeley Gas-filled Separator (BGS) Negatives: Large focal plane image Poor mass resolution High gamma background at focal plane

8. 118 117 116 288 115 88 ms 287 115 32 ms 115 114 282 113 61 ms 284 113 0.48 s 283 113 0.10 s 278 113 2 ms 113 277 112 0.7  s 112 278 111 4 ms 280 111 3.59 s 279 111 0.17 s 274 111 15 ms 272 111 3 ms 111 269 110 130  s 110 270 110 3 ms 271 110 12 ms 273 110 170  s 276 109 0.72 s 275 109 10 ms 274 109 2.91 s 266 109 2 ms 109 268 109 25 ms 270 109 3 ms 269 108 14 s 268 108 0.37 s 267 108 68 ms 266 108 4 ms 265 108 2 ms 263 108 23 ms 262 108 260  s 108 270 108 23 s 262 107 0.10 s 261 107 12 ms 260 107 32 ms 107 266 107 1 s 265 107 0.94 s 264 107 0.11 s 267 107 17 s 270 107 61 s 272 107 9.79 s 106 259 106 0.48 s 261 106 0.23 s 263 106 0.9 s 265 106 21 s 264 106 37 ms 262 106 21 ms 260 106 3.6 ms 259 105 0.5 s 258 105 4.4 s 105 260 105 1.5 s 261 105 1.8 s 262 105 34 s 263 105 27 s 267 105 73.4 h 268 105 15.9 h 266 105 22 m 267 104 77 m 258 104 12 ms 257 104 4.0 s 104 259 104 3.0 s 260 104 21 ms 261 104 2 s, 78 s 285 114 0.12 s 281 112 97 ms 277 110 5.7 ms 273 108 0.25 s 269 106 130 s 265 104 105 s 277 108 3 ms 103 256 103 28 s 255 102 3.1 m 254 101 10 m 255 101 27 m 256 101 78 m 257 101 5.52 h 253 100 3 d 256 100 158 m 259 102 58 m 260 103 180 s 259 103 6.3 s 258 102 1.2 ms 257 103 0.65 s 258 103 3.9 s 256 102 2.91 s 257 102 25 s 102 101 100 254 100 3.2 h 255 100 20 h 257 100 100 d 258 101 51.5 d 261 103 39 m 262 103 216 m 260 102 0.11 s 259 101 96 m 258 100 370  s 259 100 1.5 s 260 101 31.8 d 290 116 14 ms 271 108 4 s 263 104 8 s 294 118 1 ms 293 116 53 ms 292 116 18 ms 291 116 18 ms 287 114 0.45 s 289 114 2.70 s 288 114 0.80 s 286 114 0.12 s 282 112 0.8 ms 284 112 0.10 s 283 112 3.83 s 285 112 33.5 s 275 108 0.19 s 271 106 114 s 281 110 9.6 s 279 110 0.20 s 266 106 0.32 s 267 106 84 s 293 117 14 ms 289 115 0.22 s 285 113 5.5 s 281 111 26 s 294 117 78 ms 290 115 16 ms 286 113 20 s 282 111 0.51 s 278 109 7.7 s 274 107 0.9 m 270 105 23 h 262 104 0.19 s

10. Scheme What we want to do: Collect recoils at focal plane of BGS Separate by mass Transport low-background region

11. Space Available 6 ft Cave 2 Beamline BGS Concrete Walls Support Beams

12. ANL Built Berk. Built Scheme BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box What we want to do: Collect recoils at focal plane of BGS Separate by mass Transport low-background region

13. > 2 μm metal foil with support grid Window BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

14. He ~ 100 mbar RF + DC SHE ion retains +1 or +2 charge Cylindrical and conical section Pitch > 0.5 mm, f ~ 1 MHz SHE ions swept out by gas flow Gas Catcher BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

15. Match acceptance for mass analyzer RFQ Trap BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

16. Current design based off of segmented rfq Current ion transport simulations agree with velocity distribution and axial distribution approx. Simulations (w/ current exp. param) match current beam properties Is this sufficient? New designs are being explored to minimize timing pulse width RFQ Trap BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

17. Mass Analyzer: Requirements Fit at least 6 masses on C 3 Ability to determine implantation time High dispersion M/  M of >500 High efficiency Low extraction voltage from RFQ Fit within existing space BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

18. Mass Analyzer: The Idea Typical mass separators Wien filter TOF 90-180° Magnet Trochoid Separator - FIONA BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

19. Mass Analyzer: The Idea BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

20. Mass Analyzer: The Idea BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box Ratio of E wien /E troc

21. FIONA: Simulations BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box Einzel Lens Electrode: 50 x 20 cm, 500 V/cm Magnet 1.5 T x A= 300 301 302 303 304 A = 300-305 V acc = 4000 keV Q = 2+

22. FIONA: Simulations Det. Box A= 300 301 302 303 304 BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Einzel Lens Magnet 1.5 T x Electrode: 50 x 20 cm, 500 V/cm A = 300-304 V acc = 4 kV Q = 2+

24. What it looks like on the FPD BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box A= 300 301 302 303 304

25. FIONA: Simulations Det. Box A= 300 301 302 303 304 BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Einzel Lens Magnet 1.5 T x Electrode: 50 x 20 cm, 500 V/cm A = 300-305 V acc = 4000 kV Q = 2+

26. How to get time information BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box A= 300 301 302 303 304

27. Facility Layout 6 ft Cave 2 Beamline BGS Concrete Walls Support Beams

28. Mass Analyzer: Requirements Fit at least 6 masses on C 3 Ability to determine implantation time High dispersion M/  M of >500 High efficiency Low extraction voltage from RFQ Fit within existing space BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

29. Status and Future Currently building little-FIONA –0.55 T magnet –Xe ion source –MCP detector

30. FIONA: Simulations BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box Einzel Lens Electrode: 50 x 20 cm, 125 V/cm Magnet 0.5 T x A= 130 131 132 133 134 A = 130-134 Vacc = 1 kV Q = 1+

31. FIONA: Simulations BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box Einzel Lens Electrode: 50 x 20 cm, 125 V/cm Magnet 0.5 T x A= 130 131 132 133 134 A = 130-134 Vacc = 1 kV Q = 1+

32. What it looks like on the FPD BGSWindow Gas Catcher RFQ Trap 1 RFQ Trap 2 Extr. Accel. Mass Anal. Det. Box

33. Status and Future Currently building little-FIONA –Xe ion source –0.55 T magnet –MCP detector All parts have been ordered/designed Testing and construction will begin in June

34. Thank For Your Attention