Operators: vziskin tsentalovich vziskin
Beam tuning continued. They were able to move the septum 4 mm and still inject peak current of 95 mA with a lifetime of 23.4 (empty target). Moving the septum made the BQMs go down by a factor of about two to:
T = 109
B = 39
R = 37
L = 78
on empty target with slits in
I took an empty target run #2133 and the wire chambers appeared to have improved only marginaly (S/N ~ 2/1 to 3/1 in the front chambers, left and right respectively). However, it is clear from the vertex reconstruction that we are hitting the front of the cell, the peak is very prenounced at ~-20 cm.
Zhenya is here to do the atomic fraction studies....The atomic fraction is 48 %. We decided to coat the cell with ice as the machine group tunes the beam. Night shift should help with the tuning of the beam and after the tuning is done go home until morning. We will re-measure in the atomic fraction morning.
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:29 EST