Questions and Answers on the
For questions in the current analysis go here
1-Why did you calculate all of the Higgs branching fractions yourself
instead of taking them from Pythia or other existing SUSY/Higgs generator?
The main reason is that Pythia generates MC events for a particular
(mH, tan(b)) point, and we would like to analytically model the tan(b)
dependence so that with one dataset, say made with mH=120 GeV, we can span
the whole tan(b) axis. Just using Pythia will require the generation
of an array of datasets for different mH and tan(b) values.
In the near future we plan to use HDecay and the newest t->Hb
theoretical calculations to include fully-corrected SUSY predictions of
2-You don't include the QCD corrections to the widths for the Higgs
decays, but you do include the QCD correction for t->Wb. How big
of an effect is that QCD correction? (Jason N.)
It is not mentioned in the cdf note, however we did include the
QCD corrections for the H->csbar decay. The QCD correction for the
H->csbar decay is effectively absorbed into the quark masses. The charm
and strange masses in Eq. 5 note 7151 are the QCD-corrected values given
by Eq 22, note 4295. The H->Wbbbar decay is not QCD-corrected
in our study, nor is it in the studies we compare with in the "results"
section of the note.
3- In Table 2, you mention that you use the smallest of the relative errors for the common
Gaussian describing the correlation. Why wouldn't you use the largest
(most conservative?). Or why wouldn't you allow them to be correlated
but with a scale factor to allow for different widths. I know this
must be an extremely small point, isn't it? (Jason N.)
We have repeated this analysis using the smallest, the largest, and
the width-scale factor method for the correlation. The maximum change in
the model independent limits was of 0.7%, which is less than the 1%
error we state for the BR(t->Hb). In the model dependent analysis the
changes were even smaller, with a maximum change of 0.5% in log10(tan(b)),
which is more likely due to the error in the MC integration error than
We still used the smallest just for consistency with note 6714
(Ken and Monica's XS ratio note.)
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