Message from Steve

In cosmic runs taken on Wednesday, layer 35 sectors 7-9 and layer 47
sectors 1-4 had zero efficiency.  (This is also visible in the plot on
the 14th page of /home/pass1/histos/run215239histos.ps.gz.)

Are these sectors on the same HV channel?  Is this a HV problem?

From Dan:

The two sections are each on one HV channel, yes.  There's been some
messing around with constants lately and these have in the past been
turned off (for reasons not currently known). Xin, can you check and
see whether these channels are turned off or on at the moment and make
sure they're on in the current constants version?

Look at the picture Channel Views: <a href="png/ChannelMapWest-Down.png">West Down</a>

layer 35 sectors 7-9 => S6S1.10
layer 47 sectors 1-4 => S7S1.16 , 17

Check the "HVChannelProperties_RUN_HVNormal.txt" and "HVChannelProperties_FILL_HVNormal.txt" S6S1 CE and S7S1 CE, they are all "1" for the HVPitWest.