Re: d2 effect in Z correction

[Tom Banks <tbanks@socrates.berkeley.edu>]

> - CalibNat: As we observe ~2 increase of the capture
>    yield and the GC sees an increase of N2 from 0.2 to
>    0.4 ppm, we cannot exclude that N2 is the dominant
>    contamination for this run. But it also could be
>    H2O. Thus we have to assume an unknown mix of both
>    for the high Z correction (which induces an
>    uncertainty both via efficiency and md->mZ effect).

I don't quite understand the last sentence above... How is the uncertainty
in the impurity composition connected to the uncertainties in detection
efficiency and in the md->mZ rates?  If you refer to Equation 9 in my
analysis report from the unblinding meeting, you see that those are three
separate issues, each of which has its own associated uncertainty.  Or
maybe I'm just not understanding your phrasing?

Tom