Evening Shift, Wednesday, August 28, 2002

16:00 Run Plan Meeting Summary

Present were Ashot, David, Eugene, Mark and Valeri. Mark presented a
proposal for running for the last four shifts of this run. See his slide.
There was a consensus around accepting the proposal; essentially we
spend the evening and owl shifts trying to get some HyCal
data. Valeri, Dave and Eugene are going to work out the details of the
plan. There will have to be some choices made since the entire HyCal
run plan cannot be executed in two shifts. After tonight, we go back
to getting luminosity data, whether or not the HyCal one-shift plan is
complete.  -- MMI

20:00 Valeri calls MCC. We do not expect beam before 22:00.  -- MMI

22:00 Mark calls Crew Chief. No beam expected before midnight.

23:30 Given that we will not get beam until after midnight, Valeri and
Mark decide not to pursue the HyCal program tonight and just try for
some luminosity running. Tonight's luminosity program is described
here.

First tune the beam. If you need help, call Eugene Pasyuk.

There are four beamline devices that have to be positioned. Here are
brief instructions for each.

1. tagger radiator
   On the clas_epics gui, click on "PRIMEX TEST"
   On the primex test gui, click on radiators
   On the radiators gui, select the desired radiator
   Wait for motor to stop moving

2. photon harp
   On the clas_epics gui, click on "PRIMEX TEST"
   On the primex test gui, click on "pair spec central"
   On the pair spec central gui, click on "Converter"
   On the converter gui, select the desired converter
   Wait for motor to stop moving

3. primex target
   Find the instructions in the PrimEx paper logbook and follow them

4. TAC
   Find the instructions for "Prototype Stand Movement" on the
   "Operating Instructions for shift takers" webpage at
     http://www.jlab.org/primex/news/august_2002_beam_test/operating_instructions.html
   For TAC in, use the "TAC" command
   for TAC out, use the "park" command

Here are the six runs that we need. Let us name them 1a, 1b, 1c, 2a, 2b
and 2c. Note that they are written on the whiteboard as well.

For all of the following, use radiator "B"

1. converter = retract
   target = 1.1e-3 radiation lengths
   TAC = out

   a. beam current = 10 nA, 20 million events (10 M already taken)
   b. beam current = 100 nA, 30 million events
   c. beam current = 50 nA, 30 million events

2. converter = retract
   target = blank
   TAC = in

   a. beam current = 100 pA, 1 million events
   b. beam current = 50 pA, 1 million events
   c. beam current = 75 pA, 1 million events

For each of these runs, you will have to set the trigger. Follow the
instructions on the "Operating Instructions for shift takers" webpage.
The triggers we want are:

  T2: pair spectrometer
  T4: master OR

To get the prescale factor for T4: take the Master OR rate (see below
for how to find this) and divide it by 6 kHz.

To get the prescale factor for T2, take the prescale factor for T4 and
multiply it by 10.

To read the Master OR rate:
  On the clas_epics gui, click on "Scalers"
  The Master OR rate is about halfway down the left column of the scaler gui

If there are questions about setting the trigger, call David.

If there are questions about the run plan, call Mark.

  -- MMI

23:40 Dave changed the link so we're back to using a 10us window with
an 8 hit LIFO for the tagger TDC's. --DWL