DC folks,
A couple of items that you may be interested in:
1). I have updated the list of known missing/dead channels for all
18 drift chamber sectors following the last running period.
These lists can be viewed for each CLAS drift chamber
Region at
http://www.phys.cmu.edu/cmu/names/carman/clas/dc.html
As well, on this same page is a detailed list of all known problems
on the drift chambers (above the single SIP level). I also have
put on this web page some pretty pictures from data analysis that I
have been working on.
2). As indicated in a previous message sent out to the group, Mac and I
have been working on the so-called `speckling' problem in Region
One. The problem caused roughly 15% of the drift cells in Region
One to be lost. This was proven to result from an erroneous value
downloaded into the ROC's for the ADB pulse width jitter parameter.
We completed a pulser run yesterday with the correct jitter
parameter set up and the response from Region One is now quite
uniform. The other thing that became clear is that the pulser
system for the drift chambers requires some attention. For example
several sectors are not receiving a pulse into their TCI boards,
several sectors show the pulser response only on one connector
(i.e. the TCI/ADB is stuck and pulses only a single connector), and
Region One does not give back any pulses when the 17th pair is pulsed.
We will attempt to whip this system into shape before December.
3). The minitorus was successfully extracted from the bore this
morning without incident in preparation for shielding work and
continued work on Region One and its associated patch panels.
4). After the 3 carraiges were pulled back, Steve Christo and I went up
in the Genie lift to address connector problems that I had identified
on Region 3. We found the following items (all on the list referenced
in #1 above):
R3S1 : ST21.3 unplugged at STB
R3S2 : ST23.1,24.1,24.2 unplugged at STB
R3S4 : AX7.1 and ST7.1 swapped at the STB
AX1.1,2.1,2.2 unplugged at STB
R3S5 : ST7.2 unplugged at STB
I will continue to update the group on our progress down here in
getting the drift chambers fully prepared for e1 running in December.
If people have any questions about these items, let me know.
Daniel