ESS-Bilbao Initiative Workshop. Overview of Multi-MW Accelerator Projects

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Overview of Multi-MW Accelerator Projects with a focus on high power proton linac projects.

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ESS-Bilbao Initiative Workshop. Overview of Multi-MW Accelerator Projects

  1. 1. !quot; #& $' %
  2. 2. ! potential to deliver beams of several MW drivers for a large variety of applications: Power Energy Condensed matter spallation neutrons ~ 1 MW ~ 1 GeV materials irradiation neutrons from stripping reaction 2 x 5 MW 40 MeV RIBs for nuclear & astro-physics with neutrons 4 MW ~ 1 GeV secondary beams for particle muon, neutrino production 4 MW 5 GeV physics hybrid subcritical reactors for demonstrator 5 MW 0.6 transmutation Note: superconducting (SRF) technology higher gradient capabilities & lower operational costs wrt. NC adopted in most of the designs for the major part of the linac
  3. 3. * !5 quot;# $ ) * '% &+ $) * ') , * #) ( ) - .! * ), # ) * # ) '$ '* * ) * &* '& ) *+& quot;) * , #) & ' + * " & -) & ') * )! $* $ */ // *. /# / ' quot;# $0 quot;) % * 1) * 0 ' * ' ') # + *1 ! 2quot; 2 . 32 4 +& &# ) *& $)!2) $* * (
  4. 4. !5 4 5 4/ ! ∝ × 5. 3
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  6. 6. !7! 7 % & $ 6
  7. 7. % &$ 8 9 5. :8 8 < ; & : =>? < quot; 25 9 :   9; (5 )5 6 < (= 2* > ! 2) 3 2 * 9 . /5 6 % 6 :- 6( ? > (; < ); < 3 2 .* % 9 9 = =- -8 * quot; =- !B 0 @ - !B A 8
  8. 8. % &$ %& . @ C quot;B A quot;B A 5 5D . ) *
  9. 9. % &$ +? 2 & ! < 5 5% 8quot; E 2 .( 5 (; < 5 . ) * /< 5% -quot; E3 2 .6 5 (( ; < 5 < 5% 7 .! 55 !F 5. & ! . 3→ 2 . B
  10. 10. ' , 9 & 9 B ! E 1 BG 1 ( A 2)& 1 % C* 2quot; B A : ! E quot;B 8A ; 5 5 2 2 Particle Proton Max Beam Energy 100 MeV 2 ,%$ Operation Mode Pulsed ) . !! * Max. Peak Current 20 mA RF Frequency 350 MHz . ; Max Repetition Rate 120 Hz / 60 Hz Max Pulse Length 2 ms / 1.33 ms Max Beam Duty 24% / 8% . . .. . 100 MeV Beam Lines 20 MeV Beam Lines
  11. 11. '-> <quot; LEBT 20 MeV DTL Injector 3 MeV RFQ 50 keV 40 mA H (6 :- 3 4 ! H 5 . 3 ! . . - H H3 ; 6quot;A H I5 H <, H &quot; &quot;
  12. 12. '-> <6 ' 6 H . %B & H % .! ! * 8> > <2 quot; 8 ; )/ 5* 8 &quot; &quot; D. E β3 . ./ A86 5. 9&9 4 !) / * .
  13. 13. *. / # / ' (
  14. 14. $&# quot; %= / ! 5 * $&# 6 quot;!$ . 5* 5 kW • ! . J K. 4 6 =2 ! 160 kW quot;# $0 . quot; quot;1 9 60 kW 9 )quot; * A % 5. 400 kW ) > quot; $ ' $> * $B $ % B . *C * • . . 4 55 ! ! . LP-SPL: (Low Power) SPL PS2: High Energy PS (~ 5 to 50 GeV – 0.3 Hz) 5ν 5 ! SPS+: Superconducting SPS (50 to1000 GeV) SLHC: “Superluminosity” LH (up to 1035 cm-2s-1) DLHC: “Double energy” LHC 3
  15. 15. 5 9 #$ quot; 0 LINAC4 (160 MeV) 352.2 MHz 9 $ 4 35 H- source RFQ DTL chopper CCDTL PIMS I6;< . / /? / ) . . . / ?* / 3 50 102 160 MeV Length ~ 80 m 4 different accel. structures (352 MHz) 19 klystrons Focusing provided by 111 PM Quadrupoles 33 EM Quadrupoles 6
  16. 16. quot;# $0 !D :- &4 5 % .4 5 :D 5 36 ;2 )L 3 :- * &* ' E .( * ) 5* ( . ( 2 $ ) 5* (/ D. ( . 2 quot; 3quot; 24 6 2( ; 5 ) . D . 95 C . ) C* 9 $ $ *2 quot; 3$ quot; $2 4 56 2 ;)( * 65 5D . . . ;) 9C . ;* π * 3 4 5 2 ;)8 * 5 $2quot; $ & ! 5D . 8 5. 4 !(6 :-
  17. 17. 5 9quot; quot; 5 9! quot; LINAC4 (160 MeV) SC-Linac (4/5 GeV) 352.2 MHz 704.4 MHz H- source RFQ chopper DTL CCDTL PIMS =0.65 =1 3 102 643 MeV 50 180 MeV 4/5 GeV LP-SPL HP-SPL Energy (GeV) 4 2.5 or 5 2.5 + 5 Beam power (MW) 0.16 3 or 6 4+4 ≤2 Rep. Frequency (Hz) 50 50 Protons/pulse (x 1014) 1.5 1.5 2+1 Av. Pulse Current (mA) 20 20 40 Pulse duration (ms) 1.2 1.2 0.8 + 0.4 %G $ %G $ overall length = 460 m . 0 0 (was 690m for 2.2 GeV in previous version) 8
  18. 18. quot; 6 . 37 '? 5 4 5 / .5 /' & /! high-frequency SPL type nominal spoke option option frequency [MHz] 704.4 1408.8 352.2/1408.8 beta families 0.65/0.92 0.6/0.76/0.94 0.67/0.8/0.94 cells/cavity 5/5 40063 39937 trans. energies [MeV] 160/581 160/357/884 160/392/758 output energy [MeV] 5122 5144 5075 gradients [MV/m] 18.7*/24* 17.5*/21.3*/24.2* 8.5/9.5/24.2* cavities p. module 6/8 4/4/8 3/4/8 cavities p. period 3/8 2/4/8 3/4/8 cavities p. family 42/200 30/40/208 27/24/216 cavities in total 239 278 267 length [m] 445 499 485 &' 5 / > !B .A0 *-,
  19. 19. quot; * . * E E 5. 5 ! . 4 5 @ !5 E . E 4 5 ! β≥ /* .4 ) 4 .D 5 4! ! ) 4! 5 ( *! . 5 &quot; ' 5 . !5 . )B; A 35 45 . # .D . !5 . *
  20. 20. =/ The Intensity Frontier: Project X ( National Project with International Collaboration ) Tevatron Collider 200 kW at 8 GeV for precision measurements NOvA >2 MW at 60-120 GeV for neutrinos Main Injector 2 9;? <! quot; =F> quot; * . * &' 5. ! * * quot;$ . * ! * ' &. !G ** H ** * 53 . 5 F 8 >? < >- 4 6 * &. ;? < 5
  21. 21. Front End Linac Project X 360 kW 8GeV Linac 325 MHz 0-10 MeV 2.5 MW JPARC Modulator Modulator Klystron 1 Klystron (JPARC 2.5 MW) 16 RT Cavities 20 Klystrons (2 types) Multi-Cavity Fan-out Phase and Amplitude Control 325 MHz 10-120 MeV 436 SC Cavities 1 Klystron (JPARC 2.5 MW) H- RFQ RT SSR1 SSR1 SSR2 SSR2 SSR2 56 Cryomodules 51 Single Spoke Resonators β=0.22 β=0.4 5 Cryomodules 9 cavities/CM 11 cavities/CM Modulator Modulator Modulator 325 MHz 0.12-0.42 GeV 3 Klystrons (JPARC 2.5 MW) 42 Triple Spoke Resonators TSR TSR TSR TSR TSR TSR TSR 7 Cryomodules β=0.6 6 Cavites-6 quads / Cryomodule ILC LINAC 1300 MHz 0.42-1.2 GeV 2 Klystrons (ILC 10 MW MBK) 56 Squeezed ILC Cavities ( β=0.81) Modulator Modulator Modulator Modulator Modulator 7 Cryomodules (8 cav, 4 quads) 1300 MHz 1.2-8.0 GeV 13 Klystrons (ILC 10 MW MBK) β=0.8 β=0.8 β=0.8 β=0.8 β=0.8 β=0.8 β=0.8 ILC1 ILC1 ILC1 ILC1 ILC1 ILC1 ILC1 ILC1 287 ILC-identical Cavities 37 ILC-like Cryomodules 7 Cavities-2 quads / Cryomodule 8 Cavities - 4 quads/ Cryomodule Modulator Modulator Modulator Modulator Modulator Modulator Modulator Modulator Modulator Modulator ILC1 ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC ILC 8 Cavities-1 quad / 21 HB2008 – Project X for Intensity Frontier Physics Cryomodule
  22. 22. 1 $ .. 5 & & quot;$ $ . E B* quot; $ $ . β :8 β :>; 78
  23. 23. 1 !5 .# 3 #4 ! 5 5 -> >I : * * 1quot; $ '$ %$< 5/ 6 2 5 5 ; 4 5 2 . )* ; ) %% *& & ! . . 7 !! 55 5 : .) * 5 / 6 2 ' ;! .4 5 4 %4 & 5. 5 . . (
  24. 24. !# &2 H ! # =- !B& ( I ' & *H $ . !# $ $ . Solenoid Magnet 25 # 3
  25. 25. ! # & 2 3 '* H& 4 J . . K 5 4! . ;. # .%& !5 %& !5 F . 7! 4 ..% & 7 4 )& % * J . K 5 ! .. !7 )/ 9B %* 0 .5 ! 4 15 :$ % 0A 4 ! .2 . > 4 !A 4 13 dB Amplitude Control with Vector Modulator High-power 6 kW 3.5 ms RF Pulse Vector Modulator red trace: cavity RF Amp blue & yellow: vector HINS Room modulator bias currents Temperature Cavity 6
  26. 26. &* 7 45 7 . 5 ! . 4 5 )$* %G 4 '5 %G $ . .! 5 / A . 4 . . / . ! 5E !F 4! ! quot;9 quot; %G $ . .! 5 ; /A . . -. . . ./ .! 5E ! 4 4.
  27. 27. ' &3 4 ? ** * E * * *.5 . !quot; !quot; 8
  28. 28. '& =- !B I Beam energy 70 MeV • ECR proton source & LEBT Beam current (op.) 35 mA • RFQ (4-rod) Beam current (design) 70 mA • 6 Pairs of Coupled CH-DTL Beam pulse length 36 µs • 2 Bunchers Repetition rate 4 Hz Rf-frequency 325.224 MHz • 14 Magnetic Triplet Tot. hor emit (norm.) 2.1 / 4.2 µm • Beam power = 4.9 MW (peak) 10-3 Tot. mom. spread ¡ ¡ ¡¡ 710 W (average) Linac length 35 m • RF power = 11 MW (peak) 1600 W (average) H A =$9 M . .: . 4 5 , 0 G 5quot; 5 >' ! HA 5 : $ ! B0 3 $ 0 H 55 (
  29. 29. +& quot; $> ) B * ! 8? < 0 / 5 8? < 8 > /> * 5 RIB production Driver -? <=! GG * 5 - > <* I 3 4 Post-Accelerator Beam preparation
  30. 30. +& quot; ! & $0 . 4 9> 5 0; %&! B N N 5 . 5N <G 5 ! 4 - $ 3 <: 5 +& quot;2 9 * /* * . * * . (
  31. 31. '& ' . & ) + - )quot;% * % .4 B & 3 ;< 5 . ! 2 →3 ' 5 # 2# 2→ = 2 9 (
  32. 32. &quot;- :0> <6I :- > > * 3 (& ; !B ; % C )#E # &D # (* :- B 6 5 M (
  33. 33. &' E *& ' . H !% 6O3 2 $0> <* quot; /> ; H 5 ! &8 I !B A H& !5 . General Design: H& . ( • Houses 6 HWR and 3 superconducting solenoids • Very compact design in N/P M 4 )5 . * longitudinal direction N /6 P ( M 4 )5 . 3 * • Cavity vacuum and insulation vacuum separated M. Pekeler, LINAC 2006 ACCEL Instruments GmbH ((
  34. 34. # (3
  35. 35. 5* 2 * * .>- 7 quot;5 * 5 3> ; ->4 +5 * +5 * L+ 5 * 38 4 .. I( = 2% .! ; ; 5 $$ 2! 4 L+ 5 * 3I - 4 5 +% 9 ! .. 2B .% ! ! 5 7 .7 (6
  36. 36. quot; 2 5 (3 :- (3 :- 3 8 :- $ %C & quot;B A B B BGA GA ( 2 86 2 2 2 -. MEBT: 2 options (MCG type / solenoid-triplet type) . .! DTL: 4 tanks at 19.40, 37.68, 56.43 & 74.8 MeV, 6 cells CCL: At 972 MHz: > 60, 14 cell cavities, 3.5 separations, spoke option ? SPL: ~ 70, 4/6 cell cavities, doublet focusing, ~ 23 cells Beam power for 2 MW, 30 Hz, 3.2 GeV RCS 0.5 MW Beam pulse current before MEBT chopping 43.0 mA Beam pulse current after MEBT chopping 30.0 mA Number of injected turns for a 370 m RCS ~500 turns Beam pulse duration at the 30 Hz rep rate ~700.0 s Duty cycle for the extent of the beam pulse ~2.1 % (
  37. 37. /quot; 5 D ! . 5 :99 /= . (/& . $$ 5 5 6 :- ( 2 5 :M ) 5 9 E: 56 * quot; E B !G 5 A &( : 'E .! ) ( 2( 3 :- * $ E! 2 .O ) * 42 5 5 A OG D $ 5 O $$ O < ; /1 ' ) * (8
  38. 38. $# H ( 3 :- &B % H )( * 2 ; (5 H9 . H %C & ! .4 ) . quot; .* ! H 4 quot; B3) A (* ; &quot; / D . )9% ! * 5/ + (
  39. 39. # :G ) *QR To Ring 402.5 MHz 805 MHz HEBT MEBT DTL CCL RFQ SCL, ß=0.61 SCL, ß=0.81 Linac dump Injector 2.5 MeV 86.8 MeV 186 MeV 391 MeV 1 GeV β =0.55 β =0.71 β =0.87 Length ~260 m, 96 independently phased RF cavity/tanks Normal conducting linac from the H- ion source to 186 MeV Superconducting linac from 186 MeV to 1 GeV Beam commissioning of the SCL began in August 2005 Achieved the design repetition rate 60 Hz, maximum beam energy 1.01 GeV, peak beam current 40 mA, pulse length 1 ms, beam power on the mercury target 520 kW. (
  40. 40. -> >- A # 6 :-0 5 60 mA LP SP Funnel CCDTL CCL1 CCL2 IS RFQ Chopper DTL 114 mA 2 x 57 mA SP 100 MeV 252 MeV 1 334 MeV 60 mA 2.5 MeV 20 MeV LP 280 MHz 560 MHz 770 m A (6 # 3 8 :- 5 60 mA LP RFQ Chopper SP Funnel RFQ DTL DTL SCL1 CCL SCL2 RFQ DTL LP H+ 114 mA 2 x 57 mA SP 85 MeV 185 MeV 450 MeV 1 334 MeV 5 MeV 2 MeV 20 MeV LP 352 MHz 704 MHz 430 m 3
  41. 41. -> >= * 68 5 H # 6 :- 5 . H )5 68 . 3( 5* 3
  42. 42. # . 5 8F7F !B $ =-A0 IC> !B $ G. 5 +$ .→ B0 3 ) & $ 6 2* → : ! 9B 7 72quot; . $ β∼> β∼ 7= > 5/ . * 7I 3
  43. 43. '' Test Modules G -68-I 2$ 0> < A! E Accelerator based neutron source 8B . *8G B . *8G B A3: ) ) )* using the D-Li stripping reaction G5 B intense neutron flux with the 5 . 76 5 appropriate energy spectrum )= 5* <# 3(
  44. 44. 2. 5 ! 5 1. Injector 3. DTL O. Delferriere (Cea) N. Chauvin (Cea) IFMIF accelerator PROTOTYPE accelerator Simulations all along the linac from source to target/beam dump 2. RFQ 5 4. HEBT 5 - 57 . Gquot; C. Oliver (Ciemat) M. Comunian (Infn) 33
  45. 45. quot;9$ . #$ % & • 5 * 8>> <* 5 .3 80> 4 .3 7- π7 5E >I 7 *4 * &( ' 5 . 36
  46. 46. $& *design based on SILHI H+ source ) ! % * 5 -? 70I !B . . / // H7 ! 5) 5 quot;* H . )5 :2 5* H . . 3 . 7 !5 H 5 ;55 S T 4-electrode system Emax = 101 kV/cm $ 7 / // 1 35quot; 86 5 5 ) 1 ? quot; 1 6? quot; 1 6?* quot; ( 7 F> quot;5 5 U .) 3* V ) 55* 3
  47. 47. quot; 5. H: ! 5 . 5 B GA 5 0 . .4 . 5 → % 5 .quot; W; 55 5 LEBT to RFQ beam matching high focusing & short line solenoid solenoid RFQ krypton 4.10-5 hPa Particle density %$ 0.25 π.mm.mrad 38
  48. 48. quot; 9# # quot;5 ' &* E .( * • 5 * • >78 I < 5 3 4 5 * 0< !5 $ 3
  49. 49. RFQ Beam Dynamics 2 5 &(' $ ! ;2 H . . )/ 5* F 5 > !6 2 H 5 % &C . $ ( 5 /6 π 55/ . $ ( 4 $ 5 5 H ! 4 5 &D ! 86 :- 9 ./ 4 .# 5 •B .# 5 . ! • 9! XX55 =G. ! 5 5 4 5 . 5 •: G; 5 . •9; .5 . 4 /7 , ; B = qVλ2 mc 2 r02 3
  50. 50. RFQ Mechanical Design 5. )/5* . 5. 5. ; D 4 4 5 59 f B5 E -0.52 KHz vane tip 4 5 4,6 m $ 5E .. 4 F 4! ; 5 .5 . ;. D ! .%& . 6
  51. 51. RFQ - beam losses 9 7 45 5 H%&C 5 I/)6? 5E . * HB 4 2; 4 . “best case” “worst case” waterbag gaussian 0.25 π mm mrad 0.30 π mm mrad : @ 7IN ; : @ 78 N - ? /5 6
  52. 52. quot;9$ . $ A# 2 quot; • 5 8-I $ 0> < '' @ < . 5 H B5 / 6
  53. 53. n.c. DTL replaced by s.c. HWR DTL MS 4 cryomodules LEBT Li Target s.c. HWR Linac Ion source RFQ G 55 . * 5 ! H 5 * O 8> H 5O F H 5 6 .H . 0 . * H 5. * 6 5 H * - H 5H . Cryomodules 1 2 3&4 Cavity β 0.094 0.094 0.166 Cavity length (mm) 180 180 280 Beam aperture (mm) 40 40 48 Nb cavities / cryostat 1x8 2x5 3x4 Nb solenoids 8 5 4 . . P 3/ 25 6 # Cryostat length (m) 4.64 4.30 6.03 Output energy (MeV) 9 14.5 26 / 40 B P 3 6 55 6(
  54. 54. $ * 5& H 4 !R peak surface fields sufficiently reduced Geometry optimisation (determine the maximum reachable accelerating field) Ep/Eacc=4.4 & Bp/Eacc=10.1 Tuning method chosen: plunger at the opposite of the coupler port, in a region of high electric field (tuning range easily achieved) Tuning system actuator beam Cavity with Helium vessel Power coupler 63
  55. 55. $ * 5 . * Vacuum tank He phase separator Tuning system Collecting volume: large enough to well separate gas and liquid Exhaust pipes : diameter & path for He 2-phase flow Cavity Supply pipe + tank : minimum pressure drop Support Coupler Horizontal supply pipe: diameter large enough to be quasi isobaric on its length Solenoid magnetic design with passive shielding ! quot; On-axis field profile with passive shielding ! quot; 66
  56. 56. B E$ A • $ A# #, 0 . E/ 9 .- &' . 150 Cavity Power (kW) 125 < quot;B A ! 100 %9 & !5 . 75 * *B 9. %& Resonator index 50 0 10 20 30 40 . 5 )& G %C :* <% . %& E 78 I > .( 7- > > ! ! 3 ; :9 ) . <2 7 ;< 7 6; % <& * 8 x 200 kW 2 x 105 kW 8 x 105 kW 12 x 200 kW RF Chains RF Chains RF Chains RF Chains 175 MHz INJ RFQ MS CM 1 CM 4 100 keV 5 MeV 9 MeV 40 MeV 6
  57. 57. RF System implementation A 5- 5 45 .4 ! . * . 5 . 54 5. . 5 5 5 F quot; & 9 25 quot;' $ * 9$ quot; quot; .& = 9 & . quot; 4 )& $* .' % & 4 ) quot; %* & A5 ! 5 E 6 : )8 1 * -6 . 4 ! -. . :-;. D 195MHz 175MHz Timing Systems (Digital + Analog) Vacuum & Arcs Interlocks Host PC Windows 80 MHz Pin Digital I/O cPCI Bus Switch Digital Board Analog Analog FPGA Front End 8 DACs Front End 8 ADCs Digital IQ Demodulation IQ Ctrl 80 MHz DC 80 MHz 175 MHz Up and Control Loops Down Conversion Conversion Tuning Loop IF 175 MHz RF Reflected Circulator Voltage 1 (175MHz) RF Reflected Cavity Voltage 1 (175MHz) RF Forward Cavity Voltage 1 (175 MHz) CAVITY RF Cavity Voltage 1 (175 MHz) RF Reflected Circulator Voltage 2 (175MHz) RF Reflected Cavity Voltage 2 (175MHz) RF Forward Cavity Voltage 2 (175 MHz) CAVITY RF Cavity Voltage 2 (175 MHz) 68
  58. 58. HEBT & Beam Dump - P. A. B E$ A H25 5 - H -P* > 5 4. ; 5 H ;E * 55 F7 . Beam Dump @ < 88 I 7- G 5quot; 5 H *5 VM( 5B / 5 M6 1! / VM(5 movable Gamma shield H 5 4 F 55 ! ) 55 5 * H 5. 7 5. cooling system Beam 4! . AM Y M 4 65# S Water shield tank γ* H *5E ; *F ) ) Beam Dump Cartridge 6
  59. 59. Beam Instrumentation B E$ A# Objectives linac tuning & commissioning beam loss minimization beam characterization (emit, energy) Current, Position, Profile monitors Beam Loss, Halo, bunchlength Diagnostics Plate Detector : microstrips, grid specific beamline for a set of diags resistors for uniform electric field installed at 2 different locations (downstream RFQ and downstream DTL) Beam Transverse Profilers 2 types are developed (ionization & fluorescence) R&D started 6
  60. 60. 3 B 4 beam intensity : 125 mA resolution ~ 0.1-0.3 mm non interceptive diag residual gas ionization Detector : microstrips, grid resistors for uniform electric field beam profile 1st proto test on Silihi source at Saclay Eproton = 75 - 95 keV 1 s (32 pads = 40 mm) I < 100 mA (cw or pulsed - test < 12 mA) trigger signal
  61. 61. the P.A. of the EVEDA phase ' B'' 8 . * * H * & • Ion Source & LEBT • RFQ & MS • Cryomodule • transport line to • 1.12 MW beam dump • 175 MHz RF system • Cryogenic plant • beam instrumentation
  62. 62. IFMIF/EVEDA accelerator status Z! . 4 . 5 . $$ && E %C & ; . 5 5 5 5 quot;B A . ! ! 5 . %!5 & . 4 %5 & A 5. 5 ! . 4 5 ; 5 . 5 / A 5 ! %C & %& !5 . quot;B A 5 / 5 . ; 55 . %; ;
  63. 63. Conclusions H )9 * :9 4 H .E. 4 . 5 5 )7 % E& ! .! * ! ! HA 55 )0 .+ % * 9 H 5.5 ) B 3 9& $ $ 2 quot; 9& & * H $$ 99 && B [ 5 . ./ // (

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