Structure Testing Program R Corsini S Doebert What
Structure Testing Program R. Corsini – S. Doebert
What can we do 2007: Study Parameter Space at 30 GHz and educated guessing at 11 GHz (focus on copper structures) 2008: Focus on one main geometry, develop damping, optimize structure (Get a reference structure and try to stretch parameters from there) 2009: CLIC prototype structure working 2010: Longer term testing and better statistics Number of tests (optimistic) 2007 2008 2009 2010 sum 30 GHz 6 3 0 0 9 12 GHz 0 1 4 4 9 11. 4 GHz 2 4 2 4 8 16 Stand alone at CERN 0 3 8 8 19 sum 8 9 14 14 45 53
30 GHz program 2007 – what and how 30 GHz is for learning – concentrate on issues & comparisons rather than performance… …but need at least one good performance structure (>100 MV/m 10 -3 70 ns ? ) – have at least a couple potential ones in the list No fixed list of structures to test: No of slots will change Availability of structures will change Need to react to tests results – priorities will change ! therefore: First two slots are fixed After that, tentative priority list (to be considered in the fabrication process) In one to two months, review the list to take into account Results of previous tests Structure availability
30 GHz program 2007 - structures & what we learn - pi/2 structure (test of small phase advance, fabrication tech. ) - HDS 11 molybdenum (Moly puzzle – slope & damage limit of Mo) Tentative priority list - HDS 11 very small (r=1. 2) * (clear P/C experiment) - HDS 11 copper (clear comparison to both HDS 11 Mo & HDS 60 back) - Round 3. 5 mm, quadrants (clear comparison quadrant/round) - Coupler test structure (Igor’s idea on bandwidth) - HDS 4_150 deg_thick_r=1. 75 (iris thickness, phase advance, length, P/C) - HDS 4_150 deg_thick_clean (compares cleaning with previous) - NDS 4_150 deg_thick_r=1. 75* (comparison HDS-slots and round quadrants) - NDS 4_ 150 deg_thin (iris thickness in comparison with NDS 4_150 deg_thick) * high performance potential
New structures for 11. 4 GHz program 2007 - what we learn Two basic geometries – not very different ! - CLIC_vg 1 demonstrate the performance of up-stream ¾ of the CLIC structure demonstrate the performance of a structure which could be a back up solution for CLIC - T 23 vg 1 demonstrate the performance of a structure which could be a back up solution for CLIC (conservative approach)
Parameters of CLIC and CLICvg 1 @18 Wu CLIC_vg 1 T 23 vg 1 Frequency: f [GHz] 12 11. 424 Average iris radius/wavelength: <a>/λ 0. 128 Input/Output iris radii: a 1, 2 [mm] 3. 87, 2. 53 3. 89, 2. 85 Input/Output iris thickness: d 1, 2 [mm] 2. 66, 1. 25 1. 66 Group velocity: vg(1, 2)/c [%] 2. 4, 0. 95 2. 86, 1. 0 N. of cells, structure length: Nc, l [mm] 18, 179 25, 232 Bunch separation: Ns [rf cycles] 7 7 Number of bunches in a train: Nb 261 90 Pulse length, rise time: τp , τr [ns] 208, 19 114, 18 Input power: Pin [MW], P/C 1, 2 [GW/m] 81, 3. 3, 3. 2 110 Max. surface field: Esurfmax [MV/m] 304 307 Max. temperature rise: ΔTmax [K] 54 38 Efficiency: η [%] 31. 1 21. 9 Luminosity per bunch X-ing: Lb× [m-2] 3. 0× 1034 3. 3× 1034 Bunch population: N 7. 0× 109 8. 2× 109 Figure of merit: ηLb× /N [a. u. ] 13. 4 8. 8 Alexei
Parameters of CLIC and CLICvg 1 @14. 4 Wu CLIC_vg 1 RF phase advance per cell: Δφ [o] 120 Average iris radius/wavelength: <a>/λ 0. 128 Input/Output iris radii: a 1, 2 [mm] 3. 87, 2. 13 3. 87, 2. 53 Input/Output iris thickness: d 1, 2 [mm] 2. 66, 0. 83 2. 66, 1. 25 Group velocity: vg(1, 2)/c [%] 2. 39, 0. 65 2. 4, 0. 95 N. of cells, structure length: Nc, l [mm] 24, 229 18, 179 Bunch separation: Ns [rf cycles] 7 7 Number of bunches in a train: Nb 120 121 Pulse length, rise time: τp , τr [ns] 160, 30 127, 19 Input power: Pin [MW], P/C 1, 2 [GW/m] 76, 3. 1, 2. 7 81, 3. 3, 3. 2 Max. surface field: Esurfmax [MV/m] 323 304 Max. temperature rise: ΔTmax [K] 37 38 Efficiency: η [%] 21. 5 23. 7 Luminosity per bunch X-ing: Lb× [m-2] 2. 6× 1034 3. 0× 1034 Bunch population: N 5. 8× 109 7. 0× 109 Figure of merit: ηLb× /N [a. u. ] 9. 5 10. 2 Alexei
Alexei Red numbers are proposed priorities Name Technology Quads Disks CLIC_vg 1 (damped) X 1 ? CLIC_vg 1 (undamped) X 3 X 4 T 23 vg 1 (damped) T 23 vg 1 (undamped) CLIC_HDS (undamped) 2 X 5 X 6
11. 4 GHz program 2007 - structures & what we learn Ongoing - T 53 vg 3 Mc extend tests on present best structure – pulse length dependence - HDX 11 Moly more infos on Moly puzzle Highest priorities for 2007 - CLIC_vg 1 damped quadrants up-stream ¾ of the CLIC structure with WG damping+quadrants if successful can be a “real” CLIC prototype - T 23 vg 1 undamped disks back-up solution for CLIC, no damping yet but safest bet if successful starting point for damping + optimization Tested in 2008, depending from 2007 results - CLIC_vg 1 undamp quadrants performance loss between damping/no damping for quadrants - CLIC_vg 1 undamp disks difference disks/quadrants - CLIC_HDS damp quadrants up-stream part of HDS at same length and Fo. M as CLIC struct - CLIC_HDS undamp disks performance loss between damping/no damping for HDS infos on phase advance dependence
Possible mofifications of the program – 30 GHz - pi/2 structure ongoing - HDS 11 molybdenum X-band results not encouraging – maybe skip ? For next slot, one more structure can be available Tentative priority list - HDS 11 very small (r=1. 2) * (clear P/C experiment) - HDS 11 copper (clear comparison to both HDS 11 Mo & HDS 60 back) - Round 3. 5 mm, quadrants (clear comparison quadrant/round) - Coupler test structure (Igor’s idea on bandwidth) - HDS 4_150 deg_thick_r=1. 75 (iris thickness, phase advance, length, P/C) - HDS 4_150 deg_thick_clean (compares cleaning with previous) - NDS 4_150 deg_thick_r=1. 75* (comparison HDS-slots and round quadrants) - NDS 4_ 150 deg_thin (iris thickness in comparison with NDS 4_150 deg_thick) * high performance potential
Possible mofifications of the program – 11. 4 GHz - CLIC_vg 1 damped quadrants - T 23 vg 1 undamped disks Highest priorities for 2007 Very similar structures CLIC_vg 1 T 23 vg 1 Frequency: f [GHz] 12 11. 424 Average iris radius/wavelength: <a>/λ 0. 128 Input/Output iris radii: a 1, 2 [mm] 3. 87, 2. 53 3. 89, 2. 85 Input/Output iris thickness: d 1, 2 [mm] 2. 66, 1. 25 1. 66 Group velocity: vg(1, 2)/c [%] 2. 4, 0. 95 2. 86, 1. 0 N. of cells, structure length: Nc, l [mm] 18, 179 25, 232 Still significant extension of T 53… (300 MV/m surface field) A more conservative (and faster) approach would be a T 23 vg 3 (>vg 1. 5)
Possible mofifications of the program – 11. 4 GHz Name 2007 2008 Technology Quads Disks CLIC_vg 1 (damped) X 1 Single cell ? CLIC_vg 1 (undamped) X 4 X 5 T 23 vg 3 [vg 1] (undamped) 3 2 CLIC_HDS (damped) X 6 T 23 vg 3 [vg 1] (damped) CLIC_HDS (undamped) X 7
30 GHz & 11. 4 GHz fabrication program 2007 Germana
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