Gammasphere
Operations Manual
This on-line GS operations manual is being written. It's fairly
incomplete at the moment. Stay tuned....
Calibrations
The following calibrations should be done before an
experiment
- hi res germanium using a 207Bi source
- lo-res germanium using a 207Bi source
- side channel germanium using a 207 Bi source
After you have beam on target the following calibrations should be
done:
- first align tac2. (note that only EFF1 bins the tac2 spectrum
so you must have that EFF running to get the tac2 spectrum.)
- then align the germanium times
- then align the BGO times
- make sure the prompt time windows for the summed energy
and multiplicity are what you want. See the "where are the
time windows set?" entry in the
FAQ as to how these time
gates are set.
Make sure to dump the new parameters to files using the 'store' windows
in the tcl/tk screens so the you can recover the files later on.
Also use the 'store par button' to make sure the tcl/tk screens come up
with these file names is the tcl/tk screens windows -- if they are restarted.
Drift correction spectra
When you have been running for ~ hour with the trigger conditions you
want, you may want to save the germanium high resolution reference
spectra. You want to have enough statistics to be able to drift correct
if necessary. Yet, you want to make this dump of reference spectra not
too long after you have calibrated the array with a source so that the
detectors do not have time to drift.
Use the "Dump ref spectra" (red) button on the gecal1.tcl window
to dump the reference spectra.
During run checks
It is a good idea to do the following checks periodically
- dump the high resolution spectra. Use cfref to compare to
the stored reference spectra. If any detectors have drifter, use the drift
correction utility to bring them back. Also, look at the hit pattern
(which is also written out when you dump spectra) for any germaniums
in the noise or missing.
- Do a germanium time alignment (or look to see that the germanium
detectors are still aligned). Any time the beam is tuned (or a stripper
foil is changed), you should check the germanium times. Any time the
pre-trigger to main-trigger time is changed, you must realign the BGO
times.
- Use the receiver in the gecal2.tcl window to dump some data buffers.
Check that the FERA data looks ok, that the summed energies are
there, etc.... This utility will complain if the FERA data have errors.
Tape changes
The most standard way to change tapes is
- daq off --> end run --> tape off
- go to taper window and push the offline button
- rew - then eject (that ensures that there will be
two EOF marks on the tapes. If you only eject, there will
only be one EOF mark!)
- put a new tape in and wait for the green light to
stop blinking. At this point the blue border should
be around the online button
- push the online button
- change the experiment title and comment
- push: tape on --> begin run --> daq on
Daphne on-line sort
text still to be written
ORNL on-line sort
text still to be written
Vacuum systems
A paper write-up is available. Talk to Kim.