Dear friends,
Here is a proposal for the general comment I would like to submit to
the Bs->mumu paper along the lines as we discussed in the meeting last
friday. I have understood in the mean time that the authors are
working on a condensed version of the paper, so some of our comment
might already be solved. However, I do think we should inform the
authors of our opinion of the first draft.
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Dear authors,
This comments below result after a Nikhef group discussion of the
Bs->mumu paper draft (noting that our local Bs->mumu experts were not
involved). From your answers to other comments we have understood that
you are currently preparing a shorter version of the paper, so we here
give only our main, general, feedback.
This is an excellent (and complex) analysis leading to an important
result that will receive a lot of attention. However, it was generally
commented in our group that the paper is very dense with information
and difficult to read. Many intricacies of the analysis, although
mentioned, are difficult to understand for an outsider. In several
cases we had to turn to the analysis note to understand what was being
done (the analysis note is of excellent quality!). We get the
impression that the paper in its current state tries to include the
wealth of information of the analysis note into a letter, and therefor
becomes very difficult to read for an outsider.
In particular it was commented in our group that the "Analysis
Strategy" section in the *analysis note* was much more helpful to
understand the measurement than the corresponding section in the
paper.
(e.g. alpha = normalization factor or *single event sensitivity*).
Here are some examples that triggered our comments:
Section 5.1
It is hard to understand the exact role of MC. Although we understand
that the measurement uses data as much as possible for normalization,
the efficiency calculations are done by MC. However, the tracking
uncertainty of 4%/track is taken from another paper, where it is
calibrated with data from other channels. (By the way: is the value of
4% relevant for B->mumu?).
Section 5.2
This section is very dense with information and very difficult for a
non-LHCb collaborator to understand. If TIS-TOS-ing is new to the
reader, it is very difficult to understand the text on the bottom of
page 7.
Section 6
Here several details of the analysis could be skipped in a letter. E.g
the exact use of Crystal Ball functions and value of alpha (confusing
notation with "normalization factor" alpha).
The text of the determination of the GL with B->hh , and the solution
to the trigger TIS complication using emulation is difficult to
follow.
best regards,
- Marcel for the Nikhef/VU groups
