Re: D2 measurements

[vassilie@mail.pnpi.spb.ru]

Dear Peter,
1. in principle, we do not need to have calibration point as close as
possible to the experimental gas. Concentration factor does not depand
around small concentrations from the D2 concentration.
2. As you see I exluded any volume measurements and to use ONLY
pressure measurements and, mainly, REPRODUSIBILITY of the pressure
sensor. Volume measurements have ruther big error. So, when I
calculated the errors for the mixtures with the KNOWN deuterium
concentration I refused this procedure.

With best regards   Sasha.

On 12/1/06, Peter Kammel <kammel@npl.uiuc.edu> wrote:
> Dear Sacha, dear Oleg,
>
> One small addition to the deuterium discussion. In your draft plan you
> calibrate down to an initial deuterium conc of 5 ppm, because that's
> the limit AMS can measure with ~0.2/5 uncertainty. However, you could
> use a dilution method mixing H2 with 10 ppm deuterium to your "pure"
> protium gas. Perhaps by this volumetric method, we could go down to
> say 0.5 pp initital deuterium, which would provide calibration points
> closer to the real measurement situation.
>
> Have a nice weekend
>
> Peter
>
>


-- 
Vasilyev Alexander

Petersburg Nuclear Physics Institute,
Laboratory of Cryogenic and Superconductive Technique.