High resolution mass separator for the DESIR facility

High resolution mass separator for the DESIR facility at SPIRAL 2 Teresa Kurtukian-Nieto CEN Bordeaux-Gradignan XVIth "Colloque GANIL" Giens, September 8 th 2009

Outline HRS: initial conception Design goals Ion optical calculations Prototypes: HRS C 135 HRS Alpha Asymmetric HRS Alpha Symmetric Outlook Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 2

HRS: initial conception DESIR High resolution separator with enough mass resolution to allow isobaric separation. Resolution Teresa Kurtukian Nieto Colloque GANIL, Giens ~ 20000 September 8 th 2009 3

Design goals The design of the HRS should fulfils the following requirements : High transmission (ideally 100%) and high resolution in order to provide mono isotopic beams of exotic nuclei. Compact configuration, to be able to fit in the SPIRAL 2 production building. Should be robust in order to tolerate errors in alignment and component manufacturing. Reduced costs, concerning both installation and operation. Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 4

Design goals Resolving power: Ideal case: is the total amount of aberrations In order to get a high resolving power, a large value of small value of (x|x) and Δ are desirables. Teresa Kurtukian Nieto Colloque GANIL, Giens (x|δ) and a September 8 th 2009 5

Ion optical calculations Ion-optical code COSY INFINITY Beam emmitance: The SPIRAL 2 high intensity radio frequency cooler SHIRAC will be coupled with the high resolution separator HRS. Its purpose is to cool the radioactive beams to an emittance below 3π. mm. mrad. With cooled beams the HRS should reach its design performance in mass resolution (~20000). F. Duval talk Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 6

Monte Carlo Simulation: mass distributions Input beam: 50000 particles with mass deviations 1/20000, 0, +1/20000. Final phase spaces calculated to 5 th order Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 7

Prototypes HRS C 135 Teresa Kurtukian Nieto HRS Alpha Colloque GANIL, Giens September 8 th 2009 8

HRS C 135 (x|δ) = -26. 5 cm/% M Q S Q Q Mirror symmetric image plane point-to-point both x and y -1/20000 Object plane +1/20000 Transfer matrix (x, ) (a, ) x -1. 004793 a -0. 210 E-2 y 0. 000000 b 0. 000000 δm -26. 50605 Teresa Kurtukian Nieto (y, ) (b, ) -4. 517902 0. 000000 -1. 004670 0. 000000 0. 9991091 -0. 459 E-1 0. 000000 -0. 3695 E-1 0. 991949 -59. 73332 0. 000000 Colloque GANIL, Giens September 8 th 2009 9

COSY INFINITY X and Y motion Dm = = 26. 5 cm/% R ~ 26500 Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 10

HRS Alpha Asymmetric (x|δ) = 10 cm/% asymmetric for M plane symmetric for mid-plane (x|x) ~ 0. 5 Transfer matrix : (x, ) (a, )(y, ) (b, ) x 0. 4794806 4. 745134 0. 000000 a -0. 7961 E-2 2. 006843 0. 000000 y 0. 000000 1. 470232 3. 969397 b 0. 000000 -0. 966 E-1 0. 4193341 δm 10. 14652 -0. 224 E-04 0. 000000 Teresa Kurtukian Nieto Colloque GANIL, Giens point-to-point both x and y September 8 th 2009 11

COSY INFINITY X and Y motion Dm = ~ 10 cm/% R ~ 20000 Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 12

HRS Alpha Symmetric Same as HRSC 135 Compensation doublet Doubly symmetric: cancel high order aberrations δm = = 26. 5 cm/% M = -1. 0 Transfer matrix (x, ) (a, ) x -1. 004793 a -0. 210 E-2 y 0. 000000 b 0. 000000 δm -26. 50605 Teresa Kurtukian Nieto (y, ) (b, ) -4. 517902 0. 000000 -1. 004670 0. 000000 0. 9991091 -0. 459 E-1 0. 000000 -0. 3695 E-1 0. 991949 -59. 73332 0. 000000 Colloque GANIL, Giens September 8 th 2009 13

Outlook: GICOSY: D. Toprek TRANSPORT, GALOP ZGOUBI Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 14

Outlook: Fringe field effects COSY Infinity: Matrix with Fringe Field (FF) effects taken into account: x a y b (x, ) (a, ) -1. 004793 -0. 210 E-2 0. 000000 -4. 517902 -1. 004670 0. 000000 0. 999109 -0. 370 E-1 0. 000000 -0. 459 E-1 0. 991949 -59. 73332 0. 000000 δm -26. 50604 (y, ) (b, ) Matrix FF off: x a y b -3. 126042 -0. 946891 0. 000000 δm -26. 93832 -9. 264154 0. 000000 -3. 126042 0. 000000 0. 6700217 -11. 66724 0. 000000 0. 4723 E-1 0. 670021 -60. 48427 0. 000000 Simulations of field maps with other codes, such as TOSCA, in order to carefully evaluate the fringe field effects and later perform a more realistic study of possible misalignment effects on the resolution. Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 15

HRS working group CENBG: B. Blank, T. Kurtukian-Nieto, L. Serani GANIL: F. Varenne CSNSM Orsay: D. Lunney Institute of Nuclear Science Vinca, Belgrade : D. Toprek Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 16

Backup slides Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 17

Misalignment effects on mass resolution Phase spaces calculated to 5 th order 50000 particles with mass deviations -1/20000, 0, +1/20000. A shift in the multipole of 0. 2 mm in the x-direction induces a deformation in the x-a phase space which is responsible for the blur in the final mass separation. In this example m/ m is reduced to ~11000 Teresa Kurtukian Nieto Colloque GANIL, Giens September 8 th 2009 18