Minutes from the March 2, 2007 Tevatron Dept Meeting

https://indico.fnal.gov/conferenceDisplay.py?confId=700

* Weekly Summary (Xiaolong Zhang): There were 5 stores over the last week 
ranging in Luminosity from 133 to a record of 286.  Two shots were lost during
scraping due to steady beam loss.  The likely cause was the tunes being 
adjusted too low.  It was also determined by the cryo department that it looks
like the low beta lead flows are not being turned on early enough.  The 
sequencer has not changed, so it is unclear what is different.  Also, one store
was terminated early when the new BLM crate at F2 began corrupting the MDAT
link causing power supplies to go to the wrong current.  As a result of that
problem, a 467 card was changed for T:QDD1.  This card had a bad memory
location that ended up killing a store in the low beta squeeze.  The new
(corrected) BPM offsets have been loaded into the BPM system, and a new nominal
orbit was defined.

* LHC Schottky electronics (Ralph Pasquinelli): The E17 Schottky system is
often saturated at the beginning of a store making it difficult to use it for
tuning during the critical early part of a store.  The coherent line changes by
10 dB in the first hour.  The LHC Schottky system would offer improvements over
the present system.  High quality crystal filters can reduce the coherent line
by 90 dB.  The LHC system operates at 4.8 GHz, so a different down-converter
would be necessary for our system.  It is believed that parallel electronics
could be implemented, and tunes would be available very early after getting to
flattop (possibly even up the ramp).  This upgrade would require about $10K
from us.

* Crystal Collimator studies (Dean Still): No channeling has been observed with
the present crystal.  The area of interest from an earlier scan has been
checked multiple times, and there is not a repeat of the channeling signature. 
They are looking for access time (2-4 hrs) to measure the bend of the crystal
as well as check the rough alignment.

* Chromaticity Tracker (CY Tan): Studies were performed to check new code and
measure chromaticities under different beam conditions to determine the proper
modulation amplitude.  A 10 degree modulation provides a .0001 tune change for
a chromaticity of 5 units.  This allowed for tracking with accuracy of about 1
unit with uncoalesced beam.  The 10 degree modulation did not work will with a
single uncoalesced bunch, but 4 bunches seems to work fine.

* AC dipole and IPM (Andreas Jansson): The switch for the power supply (kicker
to AC dipole) is finished but still needs to be connected.  980 GeV beta star
measurements are desired before the LARP meeting in late March. The IPM
requires tunnel time to re-install boards.  4 more boards are supposed to
arrive in a week or so.  This also would require an access.