Subject: Review of JEM-X Scientific Validation Report


  Dear all,

  Katja Pottschmidt has taken the role of the 'non-specialist user'
and read our Scientific Validation Report. Yesterday afternoon she
discussed her findings with me, here's my summary of her findings,
which I hope is correct and sufficiently complete.

  Cheers,
  Peter

P.S. Stefan will get a marked copy of his chapter directly


Overall impressions
-------------------

* In general, Katja found the document very readable and interesting.

* It would help the users though, if there was a short overview of the
  analysis tools and their roles as well as of the sequence of analysis
  steps. This information is available in the Analysis User Manual, but
  having a briefr summary in the SVR would avoid going back and forth.

* A summary of the IC files used by the analysis would also be useful.

* The images often all come bunched at the end of a chapter, which makes
  the connection between text and image more difficult to follow.
  [Hint from the TeXniXian: use \clearpage occasionally]

* Katja had a few typesetting problems on her printout which I don't have
  printing here and also not on screen - just a warning that your PS code
  may give trouble to some people with older printers.


Detailed comments (in document order, not priority)
-----------------

* Chapter 1, p.2: 
  The PV phase is not fully public, it belongs to the INTEGRAL consortium.
  The last sentence of that paragraph is slightly misleading as it does 
  not mention the scans or the continued Crab calibrations.

* Chapter 1, p.5:
  INTEGRAL = International Gamma-Ray _Astrophysics_ Laboratory

* Section 2.1, 3rd par:
  ... two partial detector spectra were made.
  => add ref. to Figures 2.5 and 2.6

* Section 2.1
  Figures 2.3 and 2.4 seem relevant to this paragraph but are not referred
  to anywhere.

* Section 2.3 Dead time ...

  It is not clearly spelled out how large the deadtime effects are in
  practice. Fig. 2.12. could use units, or a label of the Y axis.

* Chapter 4 Imaging

  The text mentions Cyg X-3, but it is not seen in the image of Fig. 4.1,
  maybe that should be explained.

  Figure 4.2 does not explain which of the two visible brighter spots
  is actually LMC X-3 and what is to be said about the other spot.
  [Note: in b+w the spot to the lower right actually appears brighter]

* Chapter 5 Detector Binning

  It is not clear how the spectra are binned, i.e. if there is a rebinning
  taking place and which.

  Figure 5.2 does not state if this is JEM-X 1 or 2 (minor point)

* Chapter 6 Source Detection

  The achieved sensitivity should be compared to the pre-launch predictions.

* Chapter 7 Source Extraction

  This was the most difficult to read chapter in general.
  It repeats several issues already mentioned in previous chapters on one
  hand on the other hand there seems to be a lot of information in the
  figures that is not commented upon in the text. In various instances
  (e.g. Crab spectrum slope) a comparison with known or expected values
  is missing.
  
* Section 7.1, Source Spectra

  It first is stated that vignetting is the correctionof collimator 
  transmission but in the last sentence of p.40 they seem to be different
  topics => confusing.

  A recommendation for the amount of systematics to use in spectral fitting
  would be helpful.

* Section 7.3, Error estimates

  The sentence on the different relative errors is hard to understand
  and should be elaborated.

  The last sentence on p.43 mentions that longer lightcurve bins help
  but gives no indication of the conditions to be fulfilled.

* Chapter 8, Future improvements

  Error estimates should be mentioned as well


* Various smaller typos - maybe we should fax those pages to NJW ...