Content-type: text/html Manpage of ax

ax

Section: User Commands (1)
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NAME

ax - Convert ascii correlator data to Miriad for CARMA.  

PERSON RESPONSIBLE

mchw  

CATEGORIES

uv analysis  

DESCRIPTION

AX is a MIRIAD task to convert ascii correlator data to Miriad.  

PARAMETERS

in
The name of a text file containing the ascii correlation data.
out
This gives the name of the output Miriad uvdata file.
baseline
antenna pair used for this correlation data. The antenna order determines the phase. The Miriad convention is ant1 < ant2 if ant1 > ant2 then conjugate the data. Default baseline=8,9
nchan
Number of spectral channels in this correlation data file. Default nchan=15
ant
The name of a text file containing the position of the antennas. There is no default. Each line of the text file gives three values, being the x, y and z location of an antenna. The antenna positions can be given in either a right handed equatorial system or as a local ground based coordinates measured to the north, east and in elevation. See the "baseunit" parameter to specify the coordinate system. Some standard antenna configurations can be found in $MIRCAT/*.ant for ATCA, BIMA and VLA telescopes. The BIMA and VLA antenna tables, use with baseunit=1, whereas for the ATCA, use baseunit=-51.0204.

The text file is free-format, with commas or blanks used to separate the values. Comments (starting with #) can be included in the file.

baseunit
This specifies the coordinate system used in the antenna file. A positive value for "baseunit" indicates an equatorial system, whereas a negative value indicates a local system. The magnitude of "baseunit" gives the conversion factor between the baseline units used in the antenna file, and nanoseconds. The default value is +1, which means that the antenna file gives the antenna position in an equatorial system measured in nanoseconds. E.g. baseunit=-1 for topocentric coordinates in nanosecs,
    baseunit=3.33564 for geocentric coordinates in meters.
longlat
Longitude and Latitude of array phase center. hh:mm:ss,dd:mm:ss format, or as decimal hours and degrees. Default for CARMA station 32
 -118:08:29.927,37:16:49.37285.  Coordinates for some other 
    telescopes can be obtained from Miriad telepar task.
radec
Source right ascension and declination. These can be given in hh:mm:ss,dd:mm:ss format, or as decimal hours and decimal degrees. The default is to set RA = 0. and DEC = latitude.
time
Start time of the observation. This is in the form
  yymmmdd.ddd
or
  yymmmdd:hh:mm:ss.s
The default is 05OCT04 With the unix date command you can use
             date +%y%b%d:%H:%M:%S | tr '[A-Z]' '[a-z]'
Default is to take date from the ascii correlation data file.
inttime
Integration time for each record. Default inttime=10 seconds.
freq
LO1 frequency, bandwidth (GHz), and frequency band. Default 100.0,0.5,1
    The spectral channels are centered at frequencies:
Band 1 USB = LO1 + 1.0 + [1:nchan] * bandwidth/(nchan+1) GHz. Band 1 LSB = LO1 - 1.0 - [1:nchan] * bandwidth/(nchan+1) GHz. Band 2 USB = LO1 + 1.5 + [1:nchan] * bandwidth/(nchan+1) GHz. Band 2 LSB = LO1 - 1.5 - [1:nchan] * bandwidth/(nchan+1) GHz. Band 3 USB = LO1 + 2.0 + [1:nchan] * bandwidth/(nchan+1) GHz. Band 3 LSB = LO1 - 2.0 - [1:nchan] * bandwidth/(nchan+1) GHz.
    Set the bandwidth to a negative value for LSB spectrum.


 

Index

NAME
PERSON RESPONSIBLE
CATEGORIES
DESCRIPTION
PARAMETERS

This document was created by man2html, using the manual pages.
Time: 18:35:38 GMT, July 05, 2011