E-200 CHERENKOV DIAGNOSTICS RUN PLAN
FOR PENCIL BEAM STUDIES - DRAFT
E. Adli, Feb 19, 2013
Shift leaders: Erik Adli. Backups: Sebastien Corde, Spencer Gessner (SLAC)
1. Commissioning with old (2012) S20 optics
Goals:
A) Measure minimum spot size (resolution of Cherenkov system)
B) Measure dispersion at Cherenkov (energy calibration)
C) Map vignetting effects at Cherenkov
Configuration: Beam waist (<30 um x 30 um), Beam charge (<1 nC), Bunch length
(~500um)
Procedure Details:
A)
1) Verification of steering/orbit onto Cherenkov wafer; observe light on all
CHER cameras
2) Verification/location of imaging condition at Cherenkov wafer (TO BE
DISCUSSED, will take time, and can only be done for X) by scanning QS quads
3) Data acquisition with all CHER cameras. This gives the effective resolution
for each camera
Note, dipole can not be set to below 51% of nominal value (min. allowed by
betarad).
Time estimate: 30 min
Completion criteria: Spot size measurement at waist on all CHER cameras
B)
1) Scan of settings of dump dipole B5D36, from 55% of nominal value (min.
allowed by betarad, point corresponding to almost energy doubling) to 200%
of nominal value (point corresponding to plasma energy halving), in 7 steps
2) Data acquisition with all CHER cameras. This gives the effective resolution
for each camera
Time estimate: 30 min
Completion criteria: Dispersion measurement
C)
1) Scan of X, Y position of beam on wafer to verify vignetting effects and
alignment of CHER set-up, using dump dipole B5D36 for Y and
XCOR:LI20:3276. As minimum a grid of 7 x 5 points should be checked.
2) The X corrector range needed to cover the CHER field of view must be found
manually first, then the scan will be performed over the 7 x 5 points. The
CHER field of view is 4.2 cm.
3) Point 2) should be performed for both CHER NEAR and CHER FAR
Time estimate: 2 hours
Completion criteria: Vignetting mapped out, light on all 7 x 5 points, on both CHER
EGAIN and CHER ELOSS.
Total time estimate: 3 hours
2. Commissioning with new S20 optics
Procedure A) needs to be redone for the new S20 optics, to ensure nominal orbit is
still good.
In the not unlikely scenario that the first commissioning leads to adjustments of the
CHER set-up (modifications to alignment), procedure C) and possibly B) also needs
to be redone.
It is therefore important that CHER commissioning time is made available also for
pencil beam run with the new S20 optics.