Minutes of the DRAGON meeting, Tue. March 19, 2002. Present: D.Hutcheon, M. Chatterjee., A. Chen, D. Ottewell, S Bishop (recorder), A. Olin, D. Gigliotti Previous Minutes: Amend "literature values" to read "current TUDA results." Business Arising: Dave H. ran monte carlo comparing log-likelihood values for"212" 21Na(p,g for 100 trial "experiments", 18 runs in each, to SB's log-likelihood value for our one 18 run experiment. Dave finds that out of 100 "experiments", 11 produce log-likelihood values that are less probable than the experimental value of -44.45. SB reported that the four 225keV/u data points included in his data set are not corrupt as a result of Q1 being tripped off. Comparison was made between the four runs in his data set with a 225keV/u run where it was definitively known Q1 had tripped off. The hit pattern of the leaky beam on the DSSSD between the run with known tripped Q1 is sprayed over all strips of the DSSSD and the four runs included in the data set reveal a sharp leaky beam peak centred on the DSSSD. SB also investigated the issue of the two suspect runs at 215keV/u with known fault in strips 13-16 of DSSSD. Investigating the coincident recoil hit pattern on DSSSD for the remaining 16 data runs revealed that NO recoils landed on the DSSSD in strips 13-16. While it doesn't prove no counts were lost as a result of these strips being inactive, it does provide comfort for a limit value on the yield for these two runs. Hardware: AC reported ongoing work with MCP. It was discovered the previous failure of the MCP's performance with beam was a result of bias cables for the accelerating grid being reversed. Efficiency studies have been done using Gd148 alpha source. Optimal biases for electron mirror found to be V = +- 2200V, and bias for MCP found to be V = +2840V. Studies of MCP efficiency as a function of MCP bias were conducted; MCP tripped at V = +2975V. It has been noted that the ambient noise in the MCP is now ~10 times higher since that voltage trip occurred. Art Olin suggests possible surface coating could be a source of efficiency degradation -> baking. MCP Efficiency curves are attached. DG reported on gamma-array work. Work with 511 source is finished, and all looks to be OK. DG noted that 6MeV O16 source studies revealed an oddity with detector #30; namely, the gamma peak in this detector occurred at ~3MeV. Still not certain as to why this is the case. More study will be done to try to resolve the issue. Na21 822keV/u Study: DH reports that TUDA study still indicates a proton width of just 7keV for this resonance. Disagreement with AC/SE's fit still persists, with fit yielding ~14keV. AO has run a GEANT simulation for this resonance with known physicial parameters as input (known only to Art). He has tendered copies of the "data" output of these simulations to AC to do "double-blind" fits of these simulated data to verify that the fitting code is working properly. Upcoming Beam Time Use: 1. DH proposed a revisit to the Na21 822keV/u resonance to measure: a) Energy thickness of target b) Peak yield c) At least one yield measurement in upper energy "flank" of resonance Estimate of one 24 hour period for these measurements. 2. SB proposed a return to Na21 "212"keV/u resonance to measure: a) One more 215keV/u data point to replace the "corrupt" ones we currently have; verify reproducibility in general, and provide a beam energy measurement with "gas out" at this energy; something not done in the Nov. run. b) A point at 212.5keV/u to attempt to extract rising edge of yield curve. This would be helpful in determining the resonance energy. Estimate of 48 hours to complete. 3. DH proposed a measurement of dE/dx by inserting a "small aperture" gas target in place of the current target. Estimate of 1 shift to complete, preferably with stable beam. 4. DH proposed acceptance measurements using elastic Rutherford scattering, detecting scattered protons through recoil separator. Estimate 4 hours duration, preferably with stable beam. 5. Discussion followed for what resonances to move on to following the conclusion of the above four measurements. Discussion centred around the idea of measuring in ascending order of resonance energy. Discussion bogged down on the issue of the 335keV state observed only by Rolfs, as it is "next in line". SB proposed by-passing it in the interim to first make yield measurements of those states known with certainty to exist. AO proposed searching for it, as determining if it exists or not may be more important than the other measurements. DH suggested measuring the more certain states and returning to the 335keV at a time to be determined as experimental progress dictates. Abstracts: NIC-2002 abstracts were mentioned; AC will present Na21 822keV study, SE will present commissioning study, JR will present detectors/DAQ?, SB will present low energy Na21 study.