[daip] IMSTAT output

[Karl Menten]

Thanks again, Eric.
On Oct 18, 2013, at 4:44 PM, Eric Greisen <egreisen at nrao.edu> wrote:

> Karl Menten wrote:
>> Eric,
>> I loaded a single dish map into aips and added BMAJ, MIN, BPA using PUTHEAD. Here's the IMHEAD:
>> AIPS 2: Image=NONE      (MA)         Filename=I1629ASCU850.ICLN  .   1
>> AIPS 2: Telescope=                   Receiver=
>> AIPS 2: Observer=                    User #=  111
>> AIPS 2: Observ. date=01-JAN-2000     Map date=15-OCT-2013
>> AIPS 2: Minimum=-6.75735712E-01      Maximum= 2.01859531E+01
>> AIPS 2: ----------------------------------------------------------------
>> AIPS 2: Type    Pixels   Coord value     at Pixel     Coord incr   Rotat
>> AIPS 2: RA---TAN   720    16 30 49.920     360.50         -6.000    0.00
>> AIPS 2: DEC--TAN   720   -24 30 00.000     360.50          6.000    0.00
>> AIPS 2: ----------------------------------------------------------------
>> AIPS 2: Coordinate equinox 2000.00
>> AIPS 2: Map type=DIRTY               Number of iterations=       0
>> AIPS 2: Conv size=  19.00 X  19.00   Position angle=   0.00
>> AIPS 2: Maximum version number of extension files of type HI is   1
>> AIPS 2: Maximum version number of extension files of type PL is  10
>> AIPS 2: Maximum version number of extension files of type MF is   3
>> With this information added, JMFIT made a correct deconvolution.
>> However, IMSTAT just returns:
>> >imstat
>> AIPS 2: Mean= 8.400E-02 rms= 2.731E-02          over         441. pixels
>> AIPS 2: Maximum= 1.6144E-01 at     77     70     1    1    1    1    1
>> AIPS 2: Skypos: RA 16 32 55.019  DEC -24 58 59.69
>> AIPS 2: Minimum= 1.3789E-02 at     57     62     1    1    1    1    1
>> AIPS 2: Skypos: RA 16 33 03.858  DEC -24 59 47.21
>> and omits the "usual" final lines, e.g.:
>> AIPS 1: Skypos: IPOL  1420.506 MHZ
>> AIPS 1: Flux density =  2.2282E-04 Jy.   Beam area =  98.71 pixels
>> (The above values are from a different file.)
>> The file I'm working on, I1629ASCU850.ICLN  .   1, doesn't have any frequency information (nor 3rd axis) in the header, so the omission of the Skypos: IPOL line is understandable.  However, I assumed that IMSTAT would do the "statistics" with the information available and would deliver the total flux density in the area defined by BLC and TRC plus the beam area. Out of the latter, the area and the rms/pixel I then could calcylate the error in the total flux.
>> What am I missing? Do I have to PUTHEAD another paremeter?
> 
> What is missing are the image units - which appear to be either blank or unprintable characters (they should be at the end of the max/min line).
> If it is not JY/BEAM IMSTAT will not print a total flux.  I checked the task IMEAN and it also requires useful units.  I think I need to add JY/PIXEL to IMSTAT and allow dirty images (# iterations Clean = 0) to get fluxes.
> 

I have the same problem with this image, which DOES HAVE the units in the header as Jy/beam, but Map type=DIRTY:
AIPS 1: Image=IRAS1629  (MA)         Filename=IRAS1629    .IMAP  .   1
AIPS 1: Telescope=APEX-12m           Receiver=
AIPS 1: Observer=                    User #=  111
AIPS 1: Observ. date=BAD DATE        Map date=15-OCT-2013
AIPS 1: Minimum=-7.70986557E-01      Maximum= 1.74020977E+01 Jy/beam
AIPS 1: ----------------------------------------------------------------
AIPS 1: Type    Pixels   Coord value     at Pixel     Coord incr   Rotat
AIPS 1: RA---GLS   133    16 32 22.896      67.00         -3.644    0.00
AIPS 1: DEC--GLS   133   -24 28 35.616      67.00          3.644    0.00
AIPS 1: ----------------------------------------------------------------
AIPS 1: Coordinate equinox 2000.00
AIPS 1: Map type=DIRTY               Number of iterations=       0
AIPS 1: Conv size=  18.22 X  18.22   Position angle=   0.00
AIPS 1: Maximum version number of extension files of type HI is   1
AIPS 1: Maximum version number of extension files of type PL is   2
AIPS 1: Maximum version number of extension files of type MF is   3
AIPS 1: Keyword = 'ACTNOISE'  value =  1.848090E-01
AIPS 1: Keyword = 'ACTMEAN '  value = -6.751222E-03
>imstat
AIPS 1: Mean= 7.040E-02 rms= 6.607E-01 Jy/beam  over       17689. pixels
AIPS 1: Maximum= 1.7402E+01 at     67     67     1    1    1    1    1
AIPS 1: Skypos: RA 16 32 22.896  DEC -24 28 35.62
AIPS 1: Minimum=-7.7099E-01 at      8    107     1    1    1    1    1
AIPS 1: Skypos: RA 16 32 38.641  DEC -24 26 09.84
>


> It really helps when I can finally look at the code.

Of course we can wait with this until after you've had this opportunity.

Cheers,
Karl

> 
> Eric Greisen

---
Prof. Dr. Karl M. Menten
kmenten at mpifr-bonn.mpg.de
Director, Millimeter & Submillimeter Astronomy
Max-Planck-Institut fuer Radioastronomie
Auf dem Huegel 69, 53121 Bonn, Germany 
+49 228 525297