Minutes of DRAGON meeting, 20 March 2007.

Present:  Chris Ruiz (CR), Christof Vockenhuber (CV), Chuck Davis (CD),
Dave Hutcheon (DH), Dave Ottewell (DFOT), Goetz Ruprecht (GR),
John D'Auria (JDA), Lothar Buchmann (LB), Peter Machule (PM),
Mike Trinczek (MT) - recorder.


1. Previous minutes:

Accepted without corrections.


2. Business arising:

CV reports that Lin-Sih The from Clemson University has already incorporated
the DRAGON 40Ca(a,g) results into the reaction rate network calculations.
Within the errors, the DRAGON and AMS measurements agree over the relevant
energies.  The yield is ~40% higher than Rauscher.  Our measurement
uncertainty
contributes 5% to the final number.


3. Hardware:

DFOT laments the loss of apprentice machinist who was going to work on the
mount for the Mitutoyo Drive at the Charge Slits; he is pursuing other
options.

DH and PM are assembling the necessary parts for the Vibrating-Wire apparatus
to find a quad's magnetic centre.  PM still needs a function generator.

DH and PM have worked on sorting out the strange behaviour of backing
pumps when in AUTO mode.
DH email:
"
Peter and I have discovered the reason for the "non-reproducible"
behaviour of the backing pump when in AUTO mode.  The key information is
in the Device Note for BP31: "in auto mode this device is forced off as
long as pv31 is forced off see pv 31 note".   The Device Note for PV31
reads "When in automode this device is forced off for 15 minutes after
cg31a reaches less than 80 mtorr".

So if you turn on BV31 in Auto mode in order to start one of the turbos or
do anything else that brings the backing-line pressure below 80 mTorr and
then BP31 goes off, you can't turn BP31 back on until the 15 minutes have
elapsed OR you have to switch out of AUTO to Normal mode.
"

PM reports that Varian will give us 1300USD credit with them for the
shoddy ion gauges.  Another recently died downstream of the gas target...

DH still sees the day/night, warm/cold vacuum variations in the final-slit
box.  There is ~15% variation (5.2e-7 in morning, 6.2e-7Torr in afternoon).
We are slowly heading for ~3e-7Torr (PM recollection) or better.  From the
behaviour, it appears to be slow outgassing as opposed to an outright leak.
DSSSD box rises to 2Torr when left isolated for 2 weeks; therefore, always
vent with dry N2!


4. 22Na(p,g) preparations:

DFOT found a 16" box that could be sent to Seattle right away to speed up
progress.  They initially liked the idea but then decided there were
vacuum-sealing issues.  Instead, a 12" ISAC box has been located in the
shop which is deemed satisfactory by Seattle.

We will send the box and its relevant drawings to Seattle ASAP.  Seattle
will adjust drawing/design to account for the 12" box.  Our TRIUMF designer
will continue to work on box innards.

Next Tuesday (27 March) morning, CR, MT, JDA, DFOT, DH will remove the
ladder of targets from the ICS box in the mass-separator room.  CR and MT
have mapped out a path for transportation and will build a lead castle
for storage in the RPG cage on top of the cyclotron.

Work permit has been submitted.  Safety approval has been obtained.
CR is writing out formal plan.  We have located the TypeI container and
its trolley for transport.

Still need desiccant (from PM?), small Ar bottle, Safety surveyor,
replacement lid for ICS, digital camera, calipers.


5. 20Ne(p,g):

MT still hates Root, though progress with matching up correct database
and creating new histograms has been made.  He will continue to seek help.


6. OLIS Schedule:

DH reports that Bob Laxdal has remembered that he will be away 23-26 April
which has necessitated a change in the schedule:

16-22 April  ISAC II commissioning
23-26 April  18O for TUDRAGON
27 April on  Get ready for MAYA run

The TUDRAGON chamber is still on track in the Machine Shop.  A technical
report is needed, as is a run plan; Tom Davinson is said to be working
on both.


7. Solar Cells:

CR has tested three different types of cables and coaxial is the clear
winner with 0.9% resolution.

The purchase order is out for the cells.

Now need to talk with Brian Evans about connecting the 60 cables to the
solar-cell board, etc...


8. Bonus:

MT has the ISAC Yield Database almost ready for prime-time; for a sneak
preview, go here:

 http://www.triumf.info/facility/research_fac/yield.php