Albert's email:

Hi Jeff,

I have a few comments, but first,  this is a very good paper (compared 
to most in this little
area of activity).  Other comments:

(1) I would like to ammend the title to include "in the Energy Range of 
Neutron Beta-Decay".  

(2) The sentence beginning "The range for 43.5 keV electrons in plastic" 
is a little confusing.
Are you trying to say that the mean range is 3 orders of magnitude 
larger than the Al layer?
I have a few comments on this if that is what you mean:
 i) For backscatter, half  the mean range is the relevant scale for 
backscattered electrons.
 ii) dE/dx and backscatter in Al will be higher by roughly a factor of 2
 iii) This makes the factor of 600 quoted pretty close to 100
 iv) Perhaps we should soften our position on this to: "Backscattering 
from Al itself, or
rescattering from the Al, is therefore suppressed at a level below 1%, 
even for the lowest
energy incident electrons reported in this work.

(3) In both Sections A and B concerning the measurements, I always feel 
that a table
summarizing the systematic uncertainties are needed.  I know this will 
clearly push us
beyond brief report status, but probably we should just make this a 
normal article anyway.

(4) As before, I do feel we should put a quantitative number on the time 
variation of beam
currents during a typical run (due to charging).  Didn't we say that we 
had access to these
data?

(5) A point of curiousity: How do the extra systematic uncertainty 
(associated with extrapolation
to zero energy in integrals over q) vary with energy?

(6) At this point, I'm pretty satisfied with the chi^2 treatment.  It's 
still hard for the reader to
understand at what level the mean square deviations between experiment 
and the models are coming
in, but of course our data figures are pretty reasonable for them to 
eyeball this quantity.  Given that
we expect the point-to-point uncertainty to be much smaller than our 
overall quoted uncertainties,
wouldn't it be reasonable to state (at least) that the absolute value of 
the chi^2 associated
with all of our fits (except Be for Geant)  indicate general agreement 
between the models and theory
when the uncertainty in these fits is taken to be our overall uncertainty?

Comments (3) and (4) might require a bit more work (I don't know if you
all feel they are really important, but I do think they will add 
signifcantly to
the qualtiy of this publication).  I believe I suggested these on 
earlier versions
of the paper as well...I don't think we should cling to the Brief Report 
format if
it detracts from the value of this publication.

Thanks
Albert



Junhua's email:

Hi Jeff,
In the caption of Fig1, You were still using the old factors.
Junhua


Brad Plaster's email:

Hi Jeff,

Your paper looks pretty good.  I guess if you were looking for ways to 
shrink the text, you could eliminate the two paragraphs on p. 2 
beginning with "Fig. 1(a)..." and "Fig. 1(b)...", as the information 
contained there is essentially repeated in the caption for Fig. 1.  
Fig. 2 could also probably be "compressed" such that it is only 
as "tall" as the top panel of Fig. 1 (as there seems to be a lot of 
dead, white space in its interior).  But, whatever...

Brad