Joint PSP/Taskforce minutes for 10 Oct 2019
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(a) Updates from Tan for both PS and Task force
   (i) PS shutdown work done
      (1) Realigned RFQ and MEBT. Tuning and recovery of beam intensity is underway.
      (2) Tank 4 drift tube replaced. However Tank 2 drift tube
   developed a leak. A replacement drift tube is being made from an
   existing drift tube that was an exhibit.
      (3) Klystron 2 choke replaced.
      (4) Ceramic in Tank 7 SCL module repaired.
      (5) Toroid calibrations completed.
      (6) Vacuum leak in feedthru of 400 MeV wires repaired. Good
   example of HA, work planning done here. Required because of
   confined space work.
      (7) Repair of Booster cavity #1017 completed and is installed in
   tunnel.
      (8) Wide bore cavity waiting to be installed in test stand at
   MI60.
      (9) Various water leaks in Booster repaired.
      (10) Wire scanner at L1 pulled and repaired.
      (11) Survey at L11 for PIPII completed.
   (ii) Startup problems:
      (1) Too much sparking source A. Possibly to much Cs or gas
   pressure is too high. Work continues to reduce sparking.
      (2) RFQ power drops during start up. Reason unknown. Seems to be
   working now.
      (3) MEBT buncher sparking. Well known that buncher design
   multipactors. After a lot of conditioning, buncher is not
   sparking. Sparking can be induced if beam is sterred to the left of
   the buncher. This was seen 7 years ago, so no damage suspected.
   (iii) Task force
      (1) Injection girder
      	  (a) PIPII will start work on collimating the beam in the BTL
   so that waste beam is greatly reduced in Bosoter.
      	   (b) Another idea is to inject at 700 MeV rather than 800
   MeV. 
     (2) Lattice:
     	 (a) 2 methods for correcting 1/2 integer has been
   proposed. Studies will be done to see which method is better. The
   plan is to have studies when we startup.
     (3) Digital LLRF
     	 (a) Module is half way done. RF section is missing. Tan wants
   to have the LLRF module tested before the 2020 shutdown at the end
   of May.
        (b) There will be a meeting with Brian C. to discuss how PIPII
   will phase lock and inject into Booster soon.
     (4) Magnet girder tests at E4R
     	 (a) E4R needs to be cleaned up. This is a high priority task
   for Mechanical and EE support.
        (b) Fernando Juarez (Mech. Support) will be taking the lead
   for the cleanup task.
     (5) 20 Hz infrastructure
     	 (a) First meeting held on 19 Sep 2019. Docs on
   beamdocs. There are many items that need attention. Both Dave
   C. and Tan agree that there needs to be followup. Names will be
   assigned and periodic reports will need to be made.
   (6) 2 stage collimators.
       (a) Work will start in November after the PIPII task code has
   been assigned.
   (7) Wide gap gradient magnets
       (a) Valeri K. will be calculating the required gap size so that
   TD can start work on it. Expect results by the end of October.
   (8) Shielding assessment. First meeting held. M. Vincent (Safety) will be
   taking the lead. Tan will check whether Mike will also be working
   on MI shield assessement as well.
   (9) Tevatron tunnel mods for the BTL
       (a) The BTL will no longer use rolled quads to get over the
   berm. It will go through the Tev tunnel. If magnets need to be
   moved, the vacuum pipe will be removed.

(b) Jeff talked about the effect on the orbit if the corrector package
at L11 is removed in PIPII
   (1) Jeff compared the current flat injection scheme with the PIPII
   injection assuming that the compensation is symmetric about Bdot =
   0.
	(i) Chandra poins out the the present flat injection is
	asymmetric about Bdot=0 because if it is symmetric, the dipole
	correctors have to slew to match the GMPS ramp.
	(ii) Chandra also points out the for PIPII 20 Hz ramp, the
	injection time is probably going to be longer than 600 us
	because time is needed to do some RF manipulations.
		(a) Ioanis wanted to know what sort of
		manipulations. Chandra says that the RF bucket height
		may need to be manipulated before the energy ramp
		starts.
		
     (2) For present operations, there is a 0.07% momentum error
       (symmetric about Bdot=0) during +/-200 us.
     (3) For PIPII, it is 0.18% +/-300 us.
     (4) For PIPII orbit is required to be steady a tthe foil. For
     well corrected ramp, PIPII offsets < 200 um.
     (5) The following are consequences for removal of corrector at
       L11
	(i) Naive application of compensation by using correctors to
	compensate result in large +/-4 mm orbit distortion.
        (ii) Use 3 bump to zero out error at L11. Correction gives
	offset < 1.2 mm.
	(iii) Add a constant 3 bump to re-centre orbit. Correction
       gives offset < 0.5 mm
       (iv) All the above corrections require increased slew
	rates. Short correctors require ~10 T/s while long correctors
	~4.5 T/s. PIPII will be building new supplies for flat
	injection and so need to give this spec.
         (v) The problem of voltage between the windings may be a
	   problem. Increase in voltage may be more than factors
	  of 2. This could cause problems with shorts.
        (vi) Cogging calculations show that the orbit distortion  is
     ~0.075% so should be ok.
     (3) Studies will need to be done to verify these results.
     (4) Impacts on tunes, transition crossing, half integer
       correction have not been considered at this time.
     (5) Tan says that this should be a last resort if the losses from
       the waste beam remain high in Booster and the absorber needs to
       be longer.