1. Beam instrumentation MDs
T. Lefevre on the behalf of the BI group
LSWG
2 September 2014

2. Outline Review of BI MD activities during Run 1
BI MD requests for Run 2
Conclusions
LSWG
2 September 2014

3. Beam Instrumentation MDs
What is done in MDs is what cannot be done parasitically during normal beam operation and initial beam commissioning
Special beam conditions
e.g. larger beam emittance using ADT blow-up or different bunch length
Local Orbit bumps or K-modulation
e.g. for cross-calibration of beam profile monitors, BPM or FBCT studies
Intensity scan (scraping)
e.g. for BPM or FBCT sensitivity ranges study
RF frequency change
e.g. for strip-line BPM directivity study in LSSs
LSWG
2 September 2014

4. Beam Instrumentation MDs
During each MDs period – 8h BI Shift
4-5 different activities per shift
Some in parallel whenever applicable
Usual suspects
BCT, BPM, BSRT, BGI, BWS and Schottky
Typical MDs:
First part with beam tests at injection
Ramp and beam tests at flat-top
LSWG
2 September 2014

5. Beam Instrumentation MDs
Study the performances & limitations of operational devices
Understand / Solve issues that arises during Beam Operation
e.g. BSRT Extraction Mirror heating or FBCT beam position dependency
Study the impact of known limitation
e.g. non-linearity corrections of BPM readings,
Test and develop new or modified instruments
Develop devices not yet operational
e.g. Schottky, LDM, dI/dt, ..
Test hardware modifications
e.g. BSRT gated cameras, LDM optimisation
Test firmware modifications
e.g. Modified Interlock BPM firmware
Commission new Instruments
e.g. Matching Monitors
LSWG
2 September 2014

6. Results from BI MD - Run1 BSRT / WS calibration Calibration BSRT - WS
Injected 12 bunches per beam with emittance as small as possible
Use ADT to blow-up single bunches
Different ADT strength, excitation time on different bunches
 circulating bunches with emittance spread in the 1.5 – 5 um range
Measure with WS and BSRT
Calculate BSRT magnification and point spread function to match WS
Emittances after calibration
LSWG
2 September 2014

7. Results from BI MD - Run1 Matching Monitor Preliminary Results
Inject, circulate for 1000 turns max and dump a single bunch with about 1e10p
Insert the BTVM.6L4.B1 screen and observe the monitor response turn by turns
Repeat the experiment while inserting at the same time the BTVM.7L3.B1 screen to characterize any blow-up induced by scattering on the screens themselves
Remove BTVM.7L3.B1 and repeat inject and dump several times, while smoothly increasing the bunch intensity up to 5e10p.
With low intensity, offset injection trajectory to see the effect on the matching measurements (if time allows)
I=4.48e10
I=2.23e10
I=4.5e9
LSWG
2 September 2014

8. Results from BI MD - Run1 BGI – B2 Injected 1368 nominal bunches
Set local gas pressure to 5.2e-9
Study H and V camera tilt vs beam axis
Calibration with local orbit bumps +- 1mm
Used ADT to blow-up 144b batches
 Monitor with BGI avg blow-up
LSWG
2 September 2014

9. BI situation after LS1 Modified Instruments during LS1
All of them .. Some more than other …
e.g. Schottky monitor or BSRT B1, ..
Including both Hardware, Firmware, Software changes
New Functionalities and New Instruments
ICT and BCTW for fast beam intensity monitoring
dI/dt (Fast Beam Current Change Monitor - FBCCM)
Diode Orbit system for Collimator BPM and more..
Beam Transfer Function using Tune monitor
Instability Monitoring system and trigger
Beam Gas Vertex (BGV) detector
BSRT interferometer
LSWG
2 September 2014

10. Requests for Run 2
All what will not be completed during the beam commissioning period for operational BI systems …
BLMs were not part of BI MDs – Done in MPP MDs
Already known requests:
Directional Strip-line BPMs in LSSs: comp between DOROS and WBTN
Bunch intensity study scraping nominal bunches
DOROS, Interlock BPM, dIdt, ..
Bunch length dependency of ICT & BCTW
Running the beam instable (nominal bunches)
Commissioning of Instability Monitoring triggering system
CO bumps -
BPM (non-linearity correction)
Sensitivity of beam position for ICT & BCTW, Schottky monitors
Resolution study of BSRT and WS (at injection and flat top)
LSWG
2 September 2014

11. Requests for Run 2 Already known requests continued
dI/dt (FBCCM) commissioning plan with different beam intensities and energies done with TE-MPE-MS
Emittance Blow-up using ADT
Cross-calibration between BSRT & WS
Test of new BSRT interferometer on B1
Investigating the possibility to cross-calibrate WS and BSRT using BTV in dump line
Masking of BTV interlocks limited to safe beam? Can we extract and measure with BTV a nominal bunch at 6.5 TeV ?
Commissioning of BGV
Requiring gas injection
In parallel to Van der Meer scans with SMOKE detector and BWS
LSWG
2 September 2014

12. Conclusions
During Run 1, BI MDs were extremely useful, at least for us, to better understand our devices
Even if we assume a smooth re-commissioning of operational devices, we would already need several 8 hours shifts to assess the performance of new instruments using non-standard beam conditions
Our proposal is to keep a minimum of one BI shift per MD period
LSWG
2 September 2014

13. Thanks for listening
LSWG
2 September 2014

14. Fringes ‘visibility’ contains information of proton beam size
BSRT – Interferometry (B1)
New project in collaboration with KEK (T.Mitshuashi), SLAC (A.Fisher), CELLS-ALBA (U.Iriso)
Interferometry: non-diffraction limited method widely used in electron machines to measure very small beam sizes
Fringes ‘visibility’ contains information of proton beam size
F.Roncarolo & Co
28 Aug 2014

15. Closed Orbit Bumps +-4mm @ WS and BSRT
Any new aperture and/or MPP constraint in 2015 to repeat bumps at injection and flat top?
F.Roncarolo & Co
28 Aug 2014

16. WS-BSRT Commissioning Plan Overview
Time
Beam Type
Energy [GeV]
Monitors
Comments
0.450
6.5
BSRT WS
Parasitic
Pilot ✔ ✖
Check SW (automatisms, auto-gain, auto-steering, etc…)
4hrs
Single Bunches
✔ (2hrs)
Closed Orbit Bumps
8hrs
Calibration of WS PM gain + filters settings
(4hrs)
Cross-Calibration. 6 bunches with different emittances (ADT blow-up?)
Interferometry tests, only B1
Scrubbing
Temperature + mirror deformation monitoring, reliability runs
Trains
8hrs?
Pilot? Single Bunch?
Inject circulate (ramp?) and dump, monitor beam size on BTVSE and BTVD (To be investigated)
8hrs ?
Single bunch
K-Modulation, AC dipole. Need knowledge of optics at monitors, all energies. TBD with OP and ABP
N.B.:
BSRT Interferometry can be done in parallel to imaging
BSRT mirror deformation monitoring can NOT be done in parallel to imaging
F.Roncarolo & Co
28 Aug 2014

17. BSRTM (mirror) deformation monitoring
Shack-Hartmann mask
When inserted (just after view port) excludes BSRA
Deformation to be checked with low and high intensity
Can we exclude BSRA during scrubbing and/or high intensity commissioning?
Need MD time with high intensity and no BSRA (assuming MPP ok) ?
F.Roncarolo & Co
28 Aug 2014

18. Wave front distortion measurements - Hartmann mask
T. Mitsuhashi
Very cheap
Not sensible to floor vibrations
Need
the mask as close as possible to the mirror  normally is ‘destructive’, can’t split light to other devices before the mask
mask-screen lever arm as long as possible
28 Aug 2014
F.Roncarolo & Co

19. BSRT Interferometry commissioning
Slits out  test imaging
Setup polarizer
Find horizontal polarization only
Check imaging resolution dependence on rectangular iris aperture
Insert slit H
Setup operational vertical aperture of rectangular iris
Visibility vs slit separation
Determine operational slit separation
Repeat for V
Test H and V measurements
F.Roncarolo & Co
28 Aug 2014

20. Halo Monitoring via Sync light
Studies for HighLumi
Coronagraph?
Flipping Micro-Mirrors ?
Project just starting, nothing defined, not clear if any tests in 2015
F.Roncarolo & Co
28 Aug 2014