Summary of dicussion during chop-nod analysis telecon of Jan. 9, 08

Hiroko, Lero, Mike, John, Giles

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reduced-chi-squared procedures:

Mike mailed us the first results of these: reduced chi-squared maps of I,
Q and U for two dithers of IRAS 1333 4A.  Since N=2 we expect lots of
variation in the red-chi-sq values, and indeed we saw lots of variation.  
But the distributions were (very roughly) centered around unity, so in
this sense the results look to be correct.
  
For the I-map the surrounding area was full of zeros and for the Q and U
maps the surrounding area was NAN's.  Mike will investigate this, and also
the presence of some 10^60 values.

Mike will also apply this new code to the M82 February data.

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Other items:

Chopper misbehaviour needs to be addressed.  One issue is timing problems
- Hiroko will discuss with Hiro.  Another issue is changes in amplitude of
the 300" chop.  Drifts of 5 arcsec per dither, and even much worse
problems, were seen at various times during the run.  Hiroko will include
this in the report as a first step at eventual diagnosis.

Can we combine all the 2007 M82 data?  John says in principle yes, but 
beware of background subtraction problems.  

Did the recent 450 micron grid tests resolve the summer 2007 ambiguity in
the 450 micron value of "HWP flag" ?  John and Giles will coordinate.


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The following items were not discussed on the telecon:

Mike's plans to make a smoothed tau for November 2007 

Giles' plans to work on i.p.

linked list-serves for SHARP (Giles action item)

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