Ionisation Profile Monitor Proposal for ELENA IPM 17

Ionisation Profile Monitor Proposal for ELENA IPM 17 workshop, GSI 22/05/2015 Pierre Grandemange CERN BE/BI/EA

1/24/2022 Pierre Grandemange 3

Extra Low Energy Antiproton 5. 3 Me. V to 100 ke. V 2. e 7 pbar 4. e-12 mbar Why an IPM? !!! 1/24/2022 Document reference 4

Why an IPM for ELENA ? Ø Ø A scraper is already foreseen to monitor the beam profile : destructive detector The IPM is non/semi destructive Acquisition during a complete machine cycle Especially useful to characterise the electron cooling efficiency 1/24/2022 Document reference 5

ELENA cycle ELENA parameter list ELENA design report 1/24/2022 Document reference 6

IPM principle Read Out MCP V- Top electrode +- - + -+ +- -+ -+ Residual gas -+ +Beam V+ Bottom electrode BIPM principle drawing 1/24/2022 Document reference 7

IPM principle Read Out MCP BIPM principle drawing 1/24/2022 Document reference 8

Ionisation rate antiproton flux gas density H 2 @ 3. 8 e-12 mbar gas ionisation cross section with antiprotons @ 100 ke. V linear ionisation rate @ 100 ke. V Ø 4. 6 ions /1 cm/100 ms 1/24/2022 Document reference 9

Ionisation rate Intensity [A] Kinetic energy [Me. V] Gas pressure [mbar] Ionisation rate [/m/s] ELENA extraction 4. 6 e-7 100 ke. V 3. 8 e-12 4600 AD extraction 1. 1 e-6 5. 3 Me. V 1. e-11 1300 LEIR Ar 11+ 1. 6 e-4 4. 2 Me. V/u 5. e-12 1. 3 e 6 LEIR Pb 54+ 7. 8 e-4 4. 2 Me. V/u 5. e-12 3. e 7 Beam Ø Increase detection length Ø Increase acquisition time AD – – 01/12/2014 LEIR 11/11/2014 Ø Inject gas : Gas • injection – 8. 5 e-9 mbar Alexandre Frassier Increase local pressure Alexandre Frassier BE/BI/EA • Increase ionisation probability Ø Decrease antiproton lifetime BE/BI/EA 1/24/2022 Document reference 10

Gas injection ? J. Phys. B: At Mol Opt. Phys. 44 (2011) 122001 (CERN PS 194, ASACUSA) 1/24/2022 Document reference 11

Ionisation in ELENA No gas injected 1/24/2022 Document reference 12

Ionisation in ELENA CO 2 @ 1. 0 e-11 mbar 1/24/2022 Ø 9% average pressure rise Document reference 13

blow up and large angle scattering 1/24/2022 Document reference 14

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BIPM detector Wilfried Devauchelle, 2015 Read-out tubes MCP Top electrode External dimensions: 206 x 140 x 128 mm Beam aperture: 82 x 70 mm 1/24/2022 Document reference 16

BIPM detector • Triple Z stack matched MCP Ø Ø • High vacuum compatible materials Ø Ø • inox, alumina (AL 2 O 3) and copper… and kapton… … what about vespel? ! Resistive glass Ø • Gain > 2. e 8 Long detection length : 84 mm Improve electric field quality in the bulk Orbit correction electrodes 1/24/2022 W NE Document reference 17

Integration in ELENA Bellow Gas injection Horizontal BIPM + NEXTorr D 1000 -10 Turbo-molecular pump 1/24/2022 Bellow Vertical BIPM + NEXTorr D 1000 -10 Document reference 18

Acquisition chain VME crate CERN technical network • 1 VME crate • 2 * VIPM cards Ø DDC 264 integrator • 2*4 channels positive HV ELENA timing power supply • 2*4 channels negative HV power supply BIPM V 1/24/2022 BIPM H Document reference 19

Cost estimates BIPM Vacuum chamber Vacuum Acquisition mechanics 15 k. CHF MCPs 30 k. CHF Resistive glasses 20 k. CHF Main tank 16 k. CHF BIPM flanges <10 k. CHF Support <5 k. CHF Gas injection, valves, pumping 50 k. CHF VME + CPU 2 k. CHF HV power supplies 8 k. CHF VIPM cards 3 k. CHF Cables Total 65 k. CHF 31 k. CHF 50 k. CHF 23 k. CHF <10 k. CHF 169 k. CHF 1/24/2022 Document reference 20

Conclusion An IPM is a non destructive profile detector • Efficient to monitor beam cooling efficiency • Preliminary study promising • Ø Complete transport simulation still to be done • Detector design and ECR ready 1/24/2022 Document reference 21

Ionisation in ELENA 1/24/2022 Document reference 23

Gas injection ? 1/24/2022 Document reference 24

BIPM vacuum chamber 1/24/2022 Document reference 25

Integration in ELENA 1/24/2022 Document reference 26

Schedule 1/24/2022 Document reference 27

Schedule : detector 1/24/2022 Document reference 28

Schedule 1/24/2022 Document reference 29

Schedule 1/24/2022 Document reference 30

Schedule 1/24/2022 Document reference 31

Schedule 1/24/2022 Document reference 32

Beam transport 1/24/2022 Gerard Tranquille, 2015 Document reference 33

Beam transport 1/24/2022 Gerard Tranquille, 2015 Document reference 34

Beam transport 1/24/2022 Gerard Tranquille, 2015 Document reference 35