11 March 2008

RHIC Running:  Good progress getting low energy Au colliding.  STAR saw real vertices for central and peripheral collisions at 9GeV/n root(s).  They even managed a store of 1/2 to 1 hour length, although the collision rates are low at the end of such a store. 

Difficulties reading the PHENIX scalers have made it impossible to verify Au-Au collisions at PHENIX. 

Todd determined that running with h=366 does not allow collisions at both STAR and PHENIX simultaneously.  He advocates moving to h=369 (and from E=9 to E=8 GeV/n) which will allow collision at both.  This requires retuning injection, taking 2-4 hours.  An alternative would be to shift to 5 GeV/n.  STAR needs a vernier scan, as does PHENIX.   Measured emittances out of the AGS and in RHIC were 3pi in both.

There was a discussion of the best plan for the day.  Current stores are 20-30 minutes in length.  We will work on developing collisions in PHENIX, Once there are verified collisions, they will turn on the PHENIX magnet and take some luminosity.  Then RHIC cogging will be adjusted to provide collisions at
STAR.  STAR will take 5000 events.  STAR will perform a vernier scan.  During this time PHENIX will be studying their initial data.  When STAR has completed their 9 GeV dataset, PHENIX will get collisions until their dataset is also complete.  Then there will be a vernier scan at PHENIX.  When that is complete, at approximately 5PM the switch to 5GeV/n will begin.  Injection will have to be retuned.  Then an attempt will be made to circulate 5 GeV beam in RHIC.  Once there is beam in RHIC, there will be a study of Inter Beam Scattering effects by looking at the beam lifetime at a range of intensities.  This completes the RHIC program.