[daip] AIPS TST IMAGR and ISPEC

[Anna Bartkiewicz]

Dear All,

I am using the AIPS TST version. Since ca. 13/14 April, the ISPEC task 
shows too high amplitudes for the spectrum of the image cube generated 
by IMAGR. That is likely 10 times higher.

The brightest spot is 3.9 Jy and the spectrum from ISPEC shows 70 Jy as 
you can see in the attached print screen. Can it be related to some 
changes in IMAGR or calculating the noise in ISPEC?

I would appreciate your help.


Greetings,
Anna Bartkiewicz

----------------------------------------------------------------
Dr hab. Anna Bartkiewicz, prof. NCU
Institute of Astronomy
Nicolaus Copernicus University
Gagarina 11
87-100 Torun
Poland         annan at astro.umk.pl    phone: +48 56 6113040
                                      mobile: +48 885 101 723

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Imstat over the whole cube (201 channels)

> imstat
AIPS 1: Mean= 3.797E-04 rms= 8.431E-03 JY/BEAM  over    85838256. pixels
AIPS 1: Maximum= 3.9012E+00 at    312    813    82    1    1    1    1
AIPS 1: Skypos: RA 18 35 08.1400000  DEC -07 35 04.150000
AIPS 1: Skypos: 115.3 km/s  IPOL
AIPS 1: Minimum=-4.4189E-01 at    318    844    79    1    1    1    1
AIPS 1: Skypos: RA 18 35 08.1395965  DEC -07 35 04.119000
AIPS 1: Skypos: 115.6 km/s  IPOL
AIPS 1: Flux density =  1.0627E+03 Jy   Beam area =    30.67 pixels


Imstat for one channel image with no emission

> imstat
AIPS 1: Mean=-9.454E-05 rms= 2.530E-03 JY/BEAM  over      522443. pixels
AIPS 1: Maximum= 1.2832E-02 at    405    258   201    1    1    1    1
AIPS 1: Skypos: RA 18 35 08.1337453  DEC -07 35 04.705000
AIPS 1: Skypos: 104.9 km/s  IPOL
AIPS 1: Minimum=-1.2264E-02 at    366    843   201    1    1    1    1
AIPS 1: Skypos: RA 18 35 08.1363682  DEC -07 35 04.120000
AIPS 1: Skypos: 104.9 km/s  IPOL
AIPS 1: Flux density = -1.6103E+00 Jy   Beam area =    30.67 pixels
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