Minutes of the DRAGON group meeting July 8, 2008


Present: CR(chair), LB, DH(recorder), CD,DO,UH,PM,GR, CV,LE,UG,SF


1. Hardware: issues arising from 23Mg(p,g) run
        * lock-up of DRAGON area for RIB delivery prevents access to
end-detector pre-amps.  Due to non-availability of OLIS, our stable pilot
beam (23Na) was coming from the ISAC RIB production target but it was
impossible to make trim-pot adjustments on the p/a's even though the beam
was attenuated by a factor 5e5.  Solution to be investigated: allow
'Dragon attenuator In' as an alternative to 'Dragon area secured' when the
RIB source (rather than OLIS) is selected. [CR]
        * LN2 supply to the zeolite trap went empty twice without the
on-shift people being immediately aware.  The local Sonalert can't be
heard from the counting room and may be confused with the oft-occuring
oxygen alarm in the ISAC-1 hall.  Solutions: (1) run a copy of the
Sonalert alarm to the counting room [PM], (2)make the 'low' indicator
light a named EPICS quantity, so that it can be added to the MIDAS alarm
process (Speaker process?) [CR]
        * experimenters are reminded that _both_ valves of the cleaning
Trap must be closed and the gas cell pumped out when doing beam
transmission measurements.  If only the Trap outlet valve is closed, the
residual gas level in the gas cell is enough to change ionic charge state
of the beam, giving a false number for beam transmission FC4 -> FC1.  To
avoid slow pressure drifts when gas recirculation resumes after a
transmission measurement, top up the H2 by letting in 20 Torr from the
Inlet buffer tank after valving off the roughing pump and before opening
to the Trap.
        * quality of e-logging varied from excellent to sketchy during the
23Mg running.  There are at least 2 e-logs (trshare and MIDAS) plus paper
logbook and rossum files where important info might (or might not) have
been saved.  For next run, use paper logbook for immediate storage of info
then make 'digested' versions and shift summaries in the MIDAS elog.
        * the smoothing function appears not to have been implemented for
the left XSLITM.
        * FCF current lead came disconnected.  The cup needs to be
re-brazed (at the right height).
        * EPICS Scaling page: beam time was lost because an
incorrect sequence in going from 'Recoil' to 'Change E/m/q' resulted in a
bad energy setting.  This error is easy to make because there is no
'intuitively obvious' order of making this change.  DH had circulated a
'minimalist' proposal to address this particular issue.  Discussion ranged
over other aspects of the Scaling page (can't read comments from saved
tunes, need to Restore after a Save, incremental creep of Energy value
upon repeated button clicks,...).  Decision: ask for minimal change to
address the Recoil->Beam problem, as a first step in fixing Scaling.
        * our IOC has memory overload, leading to EPICS pages freezing and
other undesirable effects.  The problem is attributed to the fact that
from isdaq04 we can have direct access to the IOC (to be able to Write to
Dragon EPICS devices from MIDAS).  Running multiple sessions of EPICS
control from isdaq04 chews up memory in the IOC; the password has been
changed and only 1 session should be run as 'dragon' from isdaq04.  Other
sessions should use the 'ruiz' account as a temporary measure.  Even with
minimal load, the IOC memory is 80% used.  Jane Richards will investigate
on a Maint. day when we give her a go-ahead.


2. Beam request strategy
     A call for requests for beam in fall/winter 2008 has gone out to a
list of undisclosed recipients.  Deadline is July 25th.
        * 23Mg beam will be requested by UG/CV.  Discussion as to whether
we need to ask for 21Na time, what allowance for overhead.
        * 33S time in August almost certainly won't have commissioned
Supernanogan source in time.  Keerthi has produced 3e9 of 33S from the
OLSI microware source: can we do something useful with it, or is it better
to give all the time to SuperN commissioning?  A third option is to do
some of both: take a few shifts of 33S from the MW source and give the
rest to SuperN commissioning (on the understanding that resources would be
available in early August to do the commissioning).  CR will make a formal
proposal to follow the Third Way.


3. AOB
        * (CV): A farewell party for LE?  General agreement in favor; Dave
Ottewell volunteered site, boat and ballistic device; BYO meat,drinks;
Friday 11th, 6:00pm.