From dmacqueen@physics.utoronto.ca Wed Jul 16 18:28:26 2003
Date: Mon, 14 Jul 2003 09:56:22 -0400
From: Dan MacQueen 
To: burkett@fnal.gov, smaria@fnal.gov, castro@fnal.gov, slaughter@fnal.gov,
     williams@williams.hep.upenn.edu
Cc: cdf_people@physics.utoronto.ca
Subject: Kaluza-Klein search paper

Dear colleagues,

Some members of the University of Toronto's CDF group read the first draft of
your recent paper, "Search for Kaluza-Klein Graviton emission in p-pbar
collisions at sqrt(s)=1.8 TeV using the Missing Energy Signature."  In general,
we found the paper to be clear and well-written.  However, we would like to
make the following comments.




1) In all cases (abstract, Pg 2, first full paragraph), "respectively" should
be preceded by a comma.

Response
OK.  Fixed.

2) It would be appropriate to include a reference to the issue of the
"naturalness problem" that the model addresses.

Response
OK.  Fixed.

3) Figure 1: Perhaps either in the caption or in the main text, you could
remind the reader that these are the lowest-order diagrams.

Response
OK.  Fixed.

4) Where the production processes are defined, the symbols "q" and "g" should
also be defined as "quarks" and "gluons".

Response
OK.  Done.


5) The jet energies are corrected for calorimeter inhomengeities and effects
of the clustering algorithm.  This should be noted (since we make cuts on
their energies) perhaps in the first full paragraph of Pg. 4 or earlier on Pg
3 when the jet algorithm is defined.

Response
We are not using corrected jets, if this is what you mean



6) p.4, par. 2: When you define K as \sigma_{NLO}/\sigma_{LO}, you do not
explicity define \sigma{NLO} or \sigma{LO}.

Response
OK.  Fixed



7) On pg. 4, in the second full paragraph, you lead with a conclusion that is
not apparent until later ("The resulting sample is mainly composed of QCD
produced events.").  In fact, the ultimate sample is NOT mainly composed of
QCD events.  It may be more appropriate to say that "Based on earlier jet
studies, we expect the resulting sample to be mainly composed of QCD-produced
events, where the observed missing energy is largely a result of....").

Response
We changed the order and it is cleaner now.  Thanks.


8) p.4, par. 3: When you talk about "\delta\phi between the missing Et vector
and any jet in the event...", does "any jet" include jets which have an Et
below 15 GeV or |eta| > 1.1? 

Response
A jet is counted as a jet when when it has 15 GeV of energy in cone 0.7.  
We have added it to the jet definiton.


9) "tt" is not defined (bottom of Pg. 4).
Response
It is actually not required by PRL.  The reader is expected to know that 
$t$ refers to a top quark.

10) Table 1: Not all of the cuts mentioned in Table 1 are mentioned in the
text, and the ones that are aren't necessarily mentioned in the same order in
which they appear in the table.  For example, you mention the \delta\phi and
z-vertex cuts before the f_em and isolated track cuts, and you don't discuss
the missing Et cut in the text at all.

Response
You are right, we have added the missing Et cut discussion


11) On Pg 5., where the systematic uncertainties are identified, it would read
better if we state that "The total systematic uncertainty on the signal
efficiency is 25%, mostly due to uncertainties in our model for gluon
radiation (21%), jet energy scale...."

Response
OK.  We have some conflicting advice on this.  We have rewritten the
sentence.

12) p. 6, par. 1: Might it be worthwhile here to say what your results for the
limits on compactification scale R were as well?

Response 
We have these limits for K=1.0.  Thanks. 

13) Reference 11: We couldn't find this reference on SPIRES.  Looking at the
CDF publications page, we found


Observation of Diffractive J/psi Production at the Fermilab Tevatron
T. Affolder et al., The CDF Collaboration, Phys. Rev. Lett. 87, 241802 (2001).

and

Search for Gluinos and Scalar Quarks in p anti-p Collisions at s**(1/2) = 1.8
TeV using the Missing Energy plus Multijets Signature
T. Affolder et al., The CDF Collaboration, Phys. Rev. Lett. 88, 041801 (2002)

Did you mean to cite the latter paper here?

Response
Yes.  Fixed.

14) Reference 15:  "The D0 Collaboration" is a singular collective noun.  Thus
"reported their limit" is not correct grammar:  Would read better if it said
"reported a limit on direct graviton...."

Response
OK.  Fixed.

15) Reference 16: Perhaps some of the information in this reference could be
expanded and put into the main text.  For example, you could say what M_D
limits were found at D0, in the previous CDF analysis, and in the LEP results.

Response
We are trying to not be directly confrontational with D0.  We do say
that the results are the best from the Tevatron.  Comparing with LEP is 
more complicated.  Also, D0 has a mistaken approach on presenting the 
results in their PRL 


Thanks again for all of your work on this analysis.

Response
Thanks very much for your comments.



Cheers,
Dan MacQueen, for CDF Toronto

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Dan MacQueen --- PhD student --- U of Toronto/Fermilab
--- (416)978-6632 -- dmacqueen@physics.utoronto.ca ---
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