Minutes of DRAGON meeting January 29, 2008
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Cast (in order of appearance): 
	DH(recorder), CR(chair), PM, CD, CV, LB, GR, UH, DO
Meeting began at 14:00 in the Board Room

0. Minutes of previous meeting 
	not yet distributed

1. Hardware
	- test of turbo pumping on DSSSD box using TP52's inter-stage 
venting port (PM,CV): pump-down rate is too slow, giving only a 
slight reduction in convection gauge pressure at ~50 mTorr.
(There may have been a leak of order 60 mTorr/minute, though.)
Conclusion: we should go ahead with the order for a small turbopump 
to get DSSSD box down to <<50 mTorr (Varian 81-T).
	- the power was off for ISAC Cooling Tower maintenance last 
Thursday.  ED2 turbopump went off.
	- VAT valve with a roughing port has been ordered for the 
end-station upgrade.
	- some of the pieces (flanges) ordered as part of the upgrade 
were not shipped, one wrong part was shipped.  CR/PM will follow up.
	- the upgrade mirror assemblies called for printed circuit 
boards (metal traces on G-10), which is beyond the capabilities of 
the Machine Shop.  Detector group (Sheffer) will do the necessary 
artwork and have the job done outside TRIUMF; outer rings will be 
done in the TRIUMF Scintillator Shop (Chan).
	- slow/fast venting of the Final slit box when big MCP foils 
are installed?  Concluded that present arrangement of a manual valve 
constriction in series with VV62 is OK.  We need the slow/fast 
pump-down sequence to be enforced by PLC interlocks.
	- 'temporary' alpha source holder (DO): has been milled (by 
PM) and needs some scribe lines, then will be ready for use.

2. Acceptance  (UH)
	- latest GEANT simulation of transmission from Charge to 
Final box gives ~85%, very close to what is measured now but 
considerably higher than was measured in 2006.  The main change has 
been adjustment of height of Q1 and Q2; UH will re-run GEANT with 
Q1/Q2 positions shifted to test the (simulated) sensitivity
	-  GEANT simulation of a scan of acceptance vs SM1Y current 
gave a symmetric peak with FWHM ~0.4 A. Measurements gave an 
asymmetric peak; could it be due to small scaled current in SM2Y?
	- we should re-visit the 12C(a,g) resonance(s) to see if they 
show improved acceptance also.
	[Digression on 17O(a,g)21Ne (24mrad cone).  Q: motivation?]

3. Beam scheduling
	- JMP/GB have decided on a RIB target sequence 
  Ta(West)/SiC(East)/SiC(W)/... 
which would put a 23Mg(p,g) run early in June.  We also need beams of 
24Mg, 27Al (for charge state dist'ns) and 23Na pilot beam, and a 21Na 
beam to calibrate e+ monitors of beam intensity.  After us would be a 
21Na run to TIGRESS, all in a 3-week block; optimizing of pilot beam 
switch-overs means the 21Na calibration would come after the 23Mg 
running.  We should be able to get a reasonable handle on e+ 
detection efficiency at the start of the run, but this has to be 
looked at more carefully. (DH will draft a plan.)
	- Supernanogan "should" be ready by April 1.  We might get 
stable beams for commissioning after May 7 and again 1-2 weeks before 
the 23Mg beam.  33S(p,g) could be run in early August.

4. 22Na(p,g)   (CR)
	- action has slowed down a bit in Seattle.  They are making 
copies of the target chip and cooled mounting piece and have done 
more implantations of 23Na.  A run on a target implanted at 30kV showed 
20% degradation after bombardment by 11 Coul at 50 uA (similar to the 
earlier experience of Stegmuller et al.?)
	- they plan to implant and test another 23Na target and then 
may be ready to run on the 22Na targets shipped from TRIUMF last year
	- the next 22Na targets that we make at TRIUMF needn't be 
much stronger the the original batch.  We have to make sure the 
schedule affords enough access to the Separator area before and after 
irradiation.  We definitely want the new targets removed before the 
actinide target test.  Preparations include: Cu 'chips' of the right 
dimensions; check out Ops familiarity with rastering program; check 
out electrical connections to target ladder (Cup? collimator?).

5. Other business
	- CV: for next week's agenda, report on Workshop

Meeting ended at 14:55