Monday 8th December

1
Monday 8th December

• Morning used for RF work (IP z, injection),
  damper noise checks.
• Stable beams period with LHCb spectrometer OFF
  lost beam after 10 minutes due to a trip of RQs
  in S12.
• The nQPS threshold were accidentally set back to
  300 mV (instead of 600 mV) after a power cycle.
  Back to 600 mV again.
• Afternoon work on injection kickers, interlock
  BPMs, tune FB.
• Work on injection protection was not started.
• In the evening first ramp with 2x2 and tune FB
  active both beams made it, but beam1 was lost
  rapidly (reason not understood).
• Then night arghhh !!
• SPS bunches of 2-4e10 ready in the ring.

2
Q Feedbacks damper

• Q FB tested and the used for the ramp.
• Noise on damper, leading to lifetime reduction is
  at least partly due to cable link to Q
  measurement system (excitation). Solution should
  be ready soon. But some noise also internal
• gtgt some time most be devoted to damper studies
  (noise etc).

3
Injection kicker MKI

• MKI delays fine tuned on bunch 1 for
  multi-bunch injection.
• Measured delays for Abort Gap Keeper signal
  that protects from injection into the abort gap
  direct links from LBDS to MKIs to ensure
  consistency of abort gap position for dump
  injection.
• gtgt requires access to activate

4
Over-injection

• Ionization chamber BLMs on TDI are now
  deactivated for losses on short time scales
  (threshold gt largest signal).
• OK in IR2.
• In IR8 we still have a strange loss signal on a
  Q3 triplet BLM

Beam1
5
Orbit during ramp

• Different for B1-B2.
• So far every ramp on B1 was different gtgt need
  orbit FB with more intensity !!!

time wrt start (s)
6
Loss distribution test _at_ 1180 GeV

• Beam moved to 1/3 resonance to check loss
  distribution and collimator setup.
• gtgt more losses in IR6 than IR7
• gtgt collimator hierarchy not correct (optics
  errors, orbit ) to be verified

7
Today 9th December

• Setup for higher intensity (TL collimation,
  injection).
• Optics measurements _at_ 450 GeV.
• Collimation and dump protection checks for higher
  intensity.
• Access for abort gap keeper.
• Leading towards
• Collisions at higher intensity in the evening
  (-gt overnight)