1. AWAKE status and readiness for phase #2
S. Mazzoni & the BI AWAKE team
AWAKE status and readiness for phase #2
14/09/2017
BI Technical Board

2. AWAKE status 3rd 2017 Proton physics run just completed;
Systematic study of Seeded Self Modulation as a function of beam and laser parameters.
Very good availability, no major issues (some with BI streak)
BPMs close to plasma cell affected by ionized Rb (slides)
Next: e- line & HW commissioning
14/09/2017
BI Technical Board

3. AWAKE status
14/09/2017
BI Technical Board

4. e-line instrumentation
TT43:
TT41
2x BTVs
5x BPMs (TRIUMF, 60 mm aperture)
7x BPMs (TRIUMF, 40 mm aperture)
TCC4 / TSG4
1x Faraday Cup
Electron spectrometer optical line
1x pepper pot
14/09/2017
BI Technical Board

5. BTVs Refurbished from CTF3, installed in August 17
1st BTV: optical line designed in Zemax with intermediate image
To be done: optical line, SW (with 10 Hz external trigger option)
Screens: chromox, Ag coated Si (OTR)
Light yield: limit with OTR. Simultaneous measurement w p+ beam: factor 100 (OTR) or 25 (Chromox) difference between p+ and e-. Under assessment
Streak: should be better due to markedly different timescales of bunches (p+: 200 ps, e- : 4 ps)
14/09/2017
BI Technical Board

6. TRIUMF BPMs
TRIUMF 40mm BPM:
1 tested with success in CALIFES. Resolutions better than 50um
7 BPMs Installed in TT43 (June 2017)
TRIUMF 60mm BPM:
1 Installed in TT41 (412351) tested with proton beam
400MHz FE test (protons) in November showed beam fluctuation in order of 100um (shot to shot). Very successful test.
2GHz FE test in December gave confusing results. A signal corresponding to ~ 300pC electron bunch was observed
5 BPMS manufactured and installed in TT41 (July 2017)
5GHz FE tests still give too high signals with proton beams. Preliminary data are confusing.
TRIUMF Electronics:
14 FE’s installed and cabled in August
All tested and calibrated with BPMs connected
CERN developed FESA class acquiring data and is operational
14/09/2017
BI Technical Board

7. BPMs and
High frequency (3GHz to ~5GHz) channel supposed to measure electron bunch position in presence of protons.
Low frequency (<3GHz) available for direct (no frequency mixing) measurements
LO tunable to select best frequency
Additional high pass filter to be installed next week
14/09/2017
BI Technical Board

8. High frequency data taken on 13.8.2017
Some measurements were performed on August 13 with protons. Presumably no laser and no Rb.
Signal on low frequency channel saturated by protons (as expected) and could not be used for measurements without external attenuators.
Signal on high frequency channel was very noisy for all X-, Y- and S
With Local oscillator switched off the signal was still present suggesting that 50dB of low frequencies attenuation in the diplexer is not enough. At least this can be fixed. Additional 40dB can be added with a 3.1 GHz high pass filter to suppress the low frequency content.
14/09/2017
BI Technical Board

9. Data continued
The waveforms look very confusing. The proton pulse is very short so the shape of the waveform is entirely defined by the response of the narrow band pass filters in the electronics front-end.
Measured waveforms vary substantially in shape and amplitude which are not explainable but indicate on complex structure of the input signal.
14/09/2017
BI Technical Board

10. TRIUMF BPMs BPM 412349-HF with FESA class 14/09/2017
BI Technical Board

11. FC, pepperpot FC (TRIUMF) installed in August 2017.
Acquisition though CAEN V965A (QDC, 0 ÷ 900 pC range, 15 bits dynamics, 200 fC resolution). Test SW developed in LabVIEW. SW section to develop FESA class
Pepper Pot instated in June 17. Contribution from Manchester university
BI provides stepper motors control system (mask, screen)
14/09/2017
BI Technical Board

12. Spectrometer line
Optical line of electron spectrometer will be installed in week 42 (16-22 Oct) along with calibration source
SW will be developed by BI with collaboration by UCL
Overall cost much higher than foreseen by UCL (eg 39 kCHF for manufacturing of supports, 20 kCHF for dark room).
14/09/2017
BI Technical Board

13. BPMs with Rb – false readings
3m upstream PC
BPM
1.6 m downstream PC
14/09/2017
BI Technical Board

14. BPM 352, 17th August 2017 Orbit data, 60 minutes span Horizontal
M. Wendt
Orbit data, 60 minutes span
Horizontal
Vertical

15. BPM 352, 17th August 2017 Raw data, 12 shots, separation time ~25 sec
M. Wendt
Raw data, 12 shots, separation time ~25 sec
200 samples ⟹ 5 μs span
delta horizontal
no laser
delta horizontal
with laser & rb
sum
no laser
sum
with laser & rb

16. BPMs 352 & 425, 4th September 2017
M. Wendt
Orbit data, direct & prediction with BPMs 311&339
with laser (4-of-5 shots) & rb (7.7e14/cm3)
downstream the laser is dumped before BPM 425
horizontal
TRIUMF stripline pickup
vertical
LEP button pickup
courtesy
Anna-Maria Bachmann

17. BPMs 352 & 425, 5th September 2017
M. Wendt
Orbit data, direct & prediction with BPMs 311&339
with laser (4-of-5 shots) & rb (7.7e14/cm3)
downstream the laser is dumped after BPM 425
horizontal
TRIUMF stripline pickup
vertical
LEP button pickup
courtesy
Anna-Maria Bachmann

18. BPMs 352 & 425, 6th September 2017
M. Wendt
Orbit data, direct & prediction with BPMs 311&339
with laser (4-of-5 shots) & rb (10e14/cm3)
downstream the laser is dumped after BPM 425
1 kV clearing field between vertical button electrodes of BPM 352
horizontal
TRIUMF stripline pickup
vertical
LEP button pickup
courtesy
Anna-Maria Bachmann

19. BPMs 352 & 425, 9th September 2017
M. Wendt
Orbit data, direct & prediction with BPMs 311&339
with laser (4-of-5 shots, reducing laser power 200 mJ →40 mJ) & rb (10e14/cm3)
downstream the laser is dumped after BPM 425
1 kV clearing field between vertical button electrodes of BPM 352
horizontal
TRIUMF stripline pickup
vertical
LEP button pickup
courtesy
Anna-Maria Bachmann

20. Summary BPM 352 & 425 BPMs perform well in absence of laser and rb
M. Wendt
Summary BPM 352 & 425
BPMs perform well in absence of laser and rb
Orbit prediction algorithm of Anna-Maria demonstrates acceptable shot-to-shot resolution dilution of 30 um
LEP button BPM suffers under laser and rb
TRIUMF stripline BPM operates still well under certain conditions
HV electrostatic field shows no improvement
Instead, my degrade the stripline BPM performance?
Need more systematic beam studies
Rb density, laser power, (BPM operation frequency)

21. Budget & outlook 2018
180 kCHF allocated for 2017, 140 kCHF spent so far (UCL will transfer 40 kCHF).
70 kCHF requested for 2018 for short (sub ps) bunch length R&D in CLEAR. Refurbish existing electro optics system, possibly in collaboration with Daresbury Univ.
No other R&D request from AWAKE collaboration (so far)
14/09/2017
BI Technical Board

23. S. Gessner
Digital cameras
14/09/2017
BI Technical Board

24. S. Gessner
Digital cameras
14/09/2017
BI Technical Board

25. S. Gessner
Digital cameras
14/09/2017
BI Technical Board

26. S. Gessner
Digital cameras
14/09/2017
BI Technical Board