Minutes of the Feb 19, 2010 Tevatron Dept Meeting

http://indico.fnal.gov/conferenceDisplay.py?confId=3153

* Weekly Operations Summary (Dean Still) - During the week there were 9 HEP 
stores in the Tevatron with Initial Luminosity ranging from 153 to 317 ub-1/s. 
One store ended in a quench and one was aborted cleanly.  51.7 pb-1 were 
integrated during the week. The Tevatron Department has been asking to keep 
the Recycler Stash at about 400 e10 for each shot while we work on losses in 
the squeeze.  There is also a problem with Pbar emittance growth at Low Beta 
and collisions.  During the week there was a separator scan done which was able
to increase the Luminosity at D0 by about 2%.  PDQ was installed in A3 to help
further diagnose any future quenches we might have in the are of a cold vacuum 
leak.  A small experiment was done where we remotely turned on a fan in the are
a of the D11 Low Beta Quads to see if it would have any effect on the quad 
motion.  A horizontal movement was seen on the lvdt, and the HLS system saw a 
vertical shift.  During 30 minutes with the fan on, the D0 Horz position 
(collision point) moved by 70 microns as orbit stabilization kept the orbit 
fairly constant in the rest of the Tevatron.

* Earthquake near Virgil IL on Feb. 10 (Jim Volk) - The magnitude 3.8 
earthquake that occurred in Northern Illinois at 3:59 AM on Feb 10 was strongly
noticed at the lab.  This quake pegged the horizontal motion sensor at B48 
kicker building for 7 seconds.  The vertical sensor was pegged for 3 seconds.  
Full scale on the seismometers indicate a motion of _+_50 micrometers.  The 
horizontal motion peaked at .38 Hz while the vertical motion has a broad peak 
around .2 Hz.  The underground seismometers at MINOS showed smaller motion 
(_+_20 micrometers).  As an aside, the quake did cause a quench at E11 where 
beam was driven into the collimator.  The BLM did catch the losses and pull the
abort, but the losses already integrated caused a quench to result anyway.

* Low Beta Lattice Measurement (Alex Valishev) - The data collected on January 
29 had poor fits when first analyzed.  A long standing bug was uncovered and 
the then the BPM data converged to a 14 um rms error.  This corresponds to a 
10 to 15% error in the beta functions.  The data showed that the horizontal and
vertical beta functions have not changed since the last measurement, but the 
coupled beta functions have.  There is possibly a very small increase in the 
vertical beta at D0.  Because of the coupling change, it is possible that the 
separation in the 1st parasitic crossing may be smaller.  A check was made and
the BPM behavior is unchanged.  There does not seem to be much in the way of 
quadrupole errors in the lattice.  There are a few moderate size skew quad
errors at locations such as A18, A45, 46, C43 and E39.  The skew quad change 
at B0 is larger than the change at D0 even though we seem to be observing 
constant motion of the quads at D0 on the tilt meters.

* RFQ project for the Fermilab Linac (CY Tan) - There is a project to replace 
the Cockroft Walton Preacceleratos with an RFQ.  The reasons for this include 
the fact that the present CW preaccs are 40 years old, uptime is getting 
difficult to maintain, and we have just lost 82 years of experience to 
retirement of the present source experts.  The proposal is to replace the 
preaccs with a magnetron source and an RFQ similar to that used by Brookhaven.
BNL made this change in 1989 and have had higher quality beam since.  The 
present plan calls for two magnetron sources to be placed on a turn table so 
that either can be rotated into position at the head of the RFQ.