DRAGON Minutes						 13 April 2004

Present: DFOT, DH, CJ (recorder), GR, ML, LB, AO, JP, DG, MT, JD, CR

FAC Status:
LB said that we do not have charge state distribution equilibrium.

DH: As we went from a target pressure of 1 to 4 torr, FCM increased by
 a factor of 10.  At 4 torr, we are far from having a charge state
 equilibrium.  With an input beam charge state of 3+, at P=0 torr, the
 average q = 3+.  At P=1 torr, the average q = 4+, and at P=4 torr, the
 average q = 5+.

AO: A new logging system logs the readings, such as pressure, on devices.

DH presented a plot of integrated CCD spot luminosity and FCM2 over time
 for the first 10k seconds of runs 12037 and 12038.  The runs were with
 12C in He.  DH said that the light output in the CCD may be proportional
 to the current, and hence, the CCD intensity could be another measure
 of beam intensity.

FCM2's scaler goes into the electronic log.

Hardware failures:
CR found that if you click on a histogram in PAW, the screen goes blank
 for about 3 seconds.

MT found that FCCH pops out on its own, and AO mentioned the fact that
 if one tries to insert FCM, it will pop out because it moves in too
 slowly for the timeout limit.

Other facility issues:

DH has asked Rolf to remove the obsolete tune scaling page from EPICS.  

AO suggested that we re-label the "Save Reference Parameters" as "Edit
Reference Parameters".

JD asked if there is a nice, detailed description of how to use the scaling 
routine, and said that we need to have one.  CR volunteered to write a 
description.

JD asked whether or not we need to worry about the 21Na+p data with respect 
to charge state equilibrium.

JD asked whether the FC4 reading is jumpy because of the cup or the beam?  
AO's answer was that it is the FC4 integration time that causes the jumpiness.

12C(a,g) plan:
LB wants to request a 6 keV/u decrease in beam energy.

DH: We are 5 keV short of being able to use ED1 and ED2.

JD: The plan for the week is to continue to measure the rest of the 
excitation function.  We should tune the beam with the prescription of 
the day, and center it if we get the same results at the same energy.  
This is for the ±5 mm experiment.

An extensive discussion ensued about possible errors that result from not 
being able to steer the beam all the way through the DRAGON, and what to 
do about it.  The electric dipoles cannot reach a high enough voltage to 
steer the beam at its run energy.

The slowness in the conditioning of ED1 is due to X-rays and limits on 
its current.  There was a discussion on how best to condition the ED's 
in less time.

DH: ED2 seems to lose its conditioning faster than ED1, however, it also 
seems to recover more quickly, too.  ML suggested that that might be 
because ED2 is closer to the end of the DRAGON where the vacuum is not 
as good.

We cannot get the ED's to a high enough voltage to see the 1- state.

AO suggested that we do a long 2+ run without changes, and then finish the 
mis-steering tests.

People should check the whiteboard in the counting room for updates on the 
12C(a,g) run plan.

LB and JD: Three more energy points remain to be done.  After completing 
them, we should return to E = 1.45 MeV/u.  At that energy, we can do 
mistuning tests.  If there is time, we can perform measurements at other 
energies.  The run with 12C will end on Tuesday.

GEANT News:
Flags in GEANT enable one to choose between a solid and a gas target.

MT is using wesgrid instead of ibm00.

AO is GEANT, through Raytrace, includes the field clamps and fringe 
fields in the simulation.

Radioactive beam plans:
CR presented a slide detailing beam and recoil energies, and predictions 
of their energy losses in the gas target, mylar window, and ion chamber.  
He would like to use the ion chamber along with the PGAC or MCP.  CR 
plans to run at the 360 keV resonance, and will perform more Monte Carlo 
simulations.

JD asked CR what his test runs are meant to accomplish.  CR said that 
they are meant to determine the separation ability of the IC at this 
resonance, and to give an indication of the level of contamination that 
will appear in the spectra.

CJ suggested that we use the IC when we run with 21Na, so that we do not 
need to switch from the DSSSD to IC when we switch from 21Na to 26Al in May.

JD: CJ and CR need to determine what size the 21Na and 26Al beam spots 
will be when they reach the end detectors.

JD: We will try to run with both 21Na and 26Al, and use the IC in mid-May.

ML: If we use the IC, can we set up the MCP and IC; i.e. do we have enough 
electronics for both detectors?  The IC contains five anodes and a cathode.

JP said that changing the PAW histograms should be fairly easy.

Christof Volcanhuber will join us in a few weeks.

Jack Hagana will not join us for a month.



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