[evlatests] planet tracking test last thursday

[Bryan Butler]

it seems i didn't make a mistake in obs2script - barry do you think the 
executor is doing the right thing?

let's take the last venus scan and dissect it.  what i have in the 
script (/home/mchost/bbutler/test2007Oct25.evla) is:

ra = [ 2.90559545714279, +0.016478664307678 ]
dec = [ +0.098054871153206, -0.00490018640881 ]
distance = [  0.67013244 ]
pmodel = PolynomialInterferometerModel(54398.73232639, ra, dec, distance)
subarray.setInterferometerModel(pmodel)

first, let's look at timing.  MJD of 54398 is right for last thursday. 
and 0.73 into the day is about right too.  the timing line in the 
OBSERVE file is:

//* *** Observation day 61,119 at 11 30 00 LST, 2007.10.25 09:25:45 MST. 


(add about an hour for the last venus scan).  the line in the ephemeris 
file for around 17:30 UT is (ra, dec, distance):

11 05 54.0881 +05 37 08.469 .670108167149845

the positions are in radians, so 2.90559 ra and 0.098 dec is about 
right.  the rates are about right, for radians/day, also.

what is in the AIPS header (and presumably in the archive) for the 
position for that scan?

ra,dec = 332.9548, 11.23683

(in degrees).

which is way off.

something seems amiss in the way the executor is taking the script 
positions and converting them.  do we have the units right?

	-bryan


Bryan Butler wrote:
> strange, since i loaded the data applying the normal flagging, etc., and 
> there is still data there for all of the calibrator scans - i.e., they 
> are not flagged as being off-source.  same is true of the various mars & 
> venus scans.
> 
> the bogus pointings are from the "new-style" scans, so i've got some 
> work to do on that obviously (on how i put it into obs2script, since i 
> had it right for doing it manually before).  i'll have a look and see 
> what i screwed up on that.
> 
> looking at the venus data more closely, the first venus scan actually 
> shows venus (it's just weak so didn't show up when looking at the 
> visibilities) when imaging.  2nd one doesn't though (but this is without 
> editing).
> 
> so, i'm only suspicious now of my new-style tracking - it probably threw 
> things off so bad by having such atrocious positions that no good data 
> was taken for mars, or for the 2nd half of the venus part.
> 
> 	-bryan
> 
> 
> Ken Sowinski wrote:
>> On Mon, 29 Oct 2007, Bryan Butler wrote:
>>> i did a planet tracking test last thursday.
>>> now, there were problems starting this file up - first i sent a
>>> malformed script, then a wierd thing happened with the operator's
>>> interface, so the operator (after talking to rich) aborted the script
>>> and restarted it.  basically things didn't really start properly
>>> observing until scan #6.
>>> i can say that this observation was a spectacular failure.  there is no
>>> properly correlated data except on a single scan - the first of the
>>> venus calibrator scans.
>>
>> I had a look at the archive to see what was happening.
>> One of the methods produced totally bogus positions
>> so that the antennas spent all their time chasing
>> around the sky.  So much so that there was not enough
>> time in calibrator scans for them to get back.  This
>> is verified by the fact that the most antennas were
>> flagged as off source most of the time.
>>
>> I did not try to look at the record closely enough to see
>> which method failed.  I don't know that the other was
>> correct, but at least it produced plausible positions
>> for Venus and Mars that were near the calibrators.
>>
>>
>> We have made plans for what to do with SW time on Tuesday.
>> Barry, if you want to do anything with this tomorrow be
>> my guest.
>>
>> I have preserved the 'f10' output during Bryan's test if
>> anyone wants to look at it more carefully.
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