1. General News since PDR (Jan. 31st 2017)
Wednesday 18th July 2018
P. Abbon, F. Belloni, F. Benedetti, G. Coulloux, F. Gougnaud,
C. Lahonde-Hamdoun, P. Le Bourlout, Y. Mariette,
J. Marroncle, J.P. Mols, V. Nadot, L. Scola
C. Thomas (ESS project leader)
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Introduction - WM after Iphi Beam test

2. Introduction - WM after Iphi Beam test
NPM for cold Linac
5 NPMs
Schedule 1.6
AIK 7.3 1 3
= 5 (IPMX + IPMY)
18/07/2018
Introduction - WM after Iphi Beam test

3. NPM: Non intrusive Profile Monitor
2 types of NPM will be used at ESS
IPM: Ionization PM
FPM: Fluorescence PM
E = OFF
E = ON
Ionization
Fluorescence
Cross-section + -
Signal1) at 90 MeV
1500 1
Space Charge effect
Design complexity
ESS location
cold part
hot part
(PRes. Gas≈10-9 mbar)
(PRes. Gas≈10-6 mbar)
1) due to electric field ) calculation done by Cyrille Thomas
18/07/2018
Introduction - WM after Iphi Beam test

4. IPM: Ionization Profile Monitor
2 types of IPM Read-outs
“strips”
conductive strips (constant width and “Gaussian” widths)
w/o MCP (MicroChannel Plate)
Faster system (LPC Caen) = signal integrator (0 to 3pC or 12pC)
“optic”
pMCP=MCP with phosphorescent screen
Optic=1 lens
CCD camera
aperture for ions or electrons
pMCP
HV connection (cooper)
CF200 flange
SMA optical connector for “UV” light
IPM cage with degraders
(MCP) + Strips
pMCP+optic+CCD
18/07/2018
Introduction - WM after Iphi Beam test

5. Introduction - WM after Iphi Beam test
PDR reminder
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Introduction - WM after Iphi Beam test

6. Introduction - WM after Iphi Beam test
Our proposition at PDR
Read-out propositions for Profile measurements
Conductive strips with/without MCP (MicroChannel Plate)
pMCP + optics + CCD
TimePix3  silicon pixelated detector (see J. Storey et al., IBIC 2017)
Read-out for comparison
2 viewports for FPM
1 viewport with 3 scintillating screens with actuator
 not used, too much background light…
 not useful, saturation (break one at low intensity)
IPHI
Started with 2 pMCPs (Photonis & Hamamatsu) + constant strips plate
 but Photonis pMCP broken “…under different lighting you may well have overlooked it. It is unlikely that cracking happens spontaneously under vacuum…” Serge Duarte Pinto from Photonis
later one, replaced by “Gaussian” strips read-out
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Introduction - WM after Iphi Beam test

7. PDR relevant decisions (1)
PDR: January 31st 2017
GoNoGo  ok
Profile measurement must be done using ions (ionization by-products)
Prototype tests should be reduced, or more concentrate
TimePix3 (Silicon pixelated detector)
really interesting, but too short time for delivery date
“allowed” to investigate the ion detection feasibility
2 Read-Outs to be investigated
conductive strips with/without MCP
MCP with phosphorescent screen (COTS)
Test beam
Iphi (Irfu Saclay: proton 3 MeV, Imax=100 mA, pulsed mode) enough for validation
Radiative background
either calculation
either on similar accelerator facility  Linac 4
Space charge simulation
MCP ageing
 still on schedule
 simulation improved on longitudinal direction
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Introduction - WM after Iphi Beam test

8. PDR relevant decisions (2)
Comparison WS / IPM
MCP ageing
Electric field simulation
Cables
 see preliminary extrapolation to ESS
 new proposition
 re-done from scratch!
 contact already taken with Edward
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Introduction - WM after Iphi Beam test

9. Introduction - WM after Iphi Beam test
IPHI beam tests
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Introduction - WM after Iphi Beam test

10. Introduction - WM after Iphi Beam test
Proton beam
E=3 MeV
Intensity from 0.5 to 100 mA
Duty cycle: 100%
Note: pulsed mode 120µs (1 Hz)
[60µs – 140µs]
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Introduction - WM after Iphi Beam test

11. IPHI: test bench on deviated line
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Introduction - WM after Iphi Beam test

12. IPHI: test bench on deviated line
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Introduction - WM after Iphi Beam test

13. Introduction - WM after Iphi Beam test
Design/test bench
the 3 IPMs
Actuator with 3 scintillating screens
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Introduction - WM after Iphi Beam test

14. Introduction - WM after Iphi Beam test
Test bench at IPHI
aperture for ions or electrons
pMCP
HV connection (cooper)
CF200 flange
SMA optical connector for “UV” light
NPM cage with degraders
details of p-MCP connection
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Introduction - WM after Iphi Beam test

15. Life is a long, but a quiet river…
Delays
Component deliveries with important delays
Most of then were postponed by few weeks, even months wrt the delivery date
the worst: last MCP received on January 4th 2018 (ordered on 29/6/17)
Vacuum: Problem with a leakage vacuum detector
Late flanges delivery with the viewports (strips, optic, HV connectors…)
Etc.
No time to test in laboratory MCPs, just an overlook on CCD cameras, HVs, Faster (strips)…
Installation on IPHI (Feb. 13th 2018)
Kind of IPHI commissioning: working for the first time with an inner diagnostics. Starting data taking completely blind, but a FC, 2 ACCTs upstream and downstream the RFQ and BPMs not connected
Problem with HVs (sparking)
impossibility to work with Photonis pMCP, we gave up in mid March, send it back to Photonis and recovered it July 11th 2018  finally no beam test with a 2nd pMCP!
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Introduction - WM after Iphi Beam test

16. Life is a long, but a quiet river…
MCP current consumption sometimes weird  no amplification
Faster system: no trigger before April 6th
fine beam tuning to determine workable beam conditions
first genuine profile on March 1st
Reproducibility: not so obvious
Huge background
Profiles were shifting, then drifting back like electric charge loading of IPM structure  lot of doubts, and…
finally, BPM were connected showing correlations with IPMs
Many attempts for background shielding  not really successful
Material delivery delays, Vacuum problems, broken pMCP… postponed the assembly of the test bench in our laboratory, avoiding to test systems before installation on IPHI.
Then, we were not ready when arriving at IPHI, which was not well “commissioned”…
All these events implied waste of time before achieving a first profile measurement… and explain partly why we are here today!
ion
March 1st
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Introduction - WM after Iphi Beam test

17. Introduction - WM after Iphi Beam test
among problems…
Functioning point
March 8th
9:15 HV only on IPM_2  bad profiles as shown on left bottom,
but nice vertical beam deviation correlation)
9:25 HV on IPM_2 and IPM_1 (300 V)  background swept (right bottom)
+10 A (high)
0 A (centre)
-10 A (bottom)
Ibeam=60 mA - IPM2 = 9 kV - MCP = 600 V - Phosphorus = 3500 V
9:15
9:25
Photonis pMCP broken
18/07/2018
Introduction - WM after Iphi Beam test

18. Introduction - WM after Iphi Beam test
Working meeting
ESS site visit this morning with Cyrille
This afternoon
13:30 General news since PDR (Feb. 2017), Jacques (15’+5’)
13:50 Iphi test results using Strip read-out, Francesca (25’+15’)
14:30 Iphi test results using pMCP + CCD camera read-out, Florian (25’+15’)
15:10 Coffee break
15:30 Toward CDR: plans and perspective, Jacques (25’+15’)
16:10 concluding remarks, Cyrille (20’+10’)
16:40 first general discussions, all (20’)
17:00 Adjourn
Tomorrow morning
09:00 – 11:00 closed session, committee
In the meanwhile from NPM group, meeting from 8:30 to 11:00
08:30 – 10:00 meeting with vacuum group.
10:00 – 11:00 meeting with Accelerator physics group.
11:00 – 11:30 wrap-up with NPM group, Andreas/Thom (20’+10’)
11:45 Lunch
Tomorrow afternoon
13:30 – 15:00 meeting with ICS group.  
15:00 – 16:00 meeting with BI group.
16:15 back to the airport!
18/07/2018
Introduction - WM after Iphi Beam test