Content-type: text/html Manpage of linecal

linecal

Section: User Commands (1)
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NAME

linecal - Estimate antenna gains from line length measurements.  

PERSON RESPONSIBLE

mchw  

CATEGORIES

calibration  

DESCRIPTION

LINECAL is a Miriad task to estimate the instrumental phase drifts due to line length changes. The measured phases are written as antenna gains and can be manipulated and displayed using the GP routines and BEE. The resulting gains can be plotted with GPPLT and smoothed to reduce the noise with GPAVER. The gains for bad line length phases can be edited with GPEDIT, or with BEE if you want to do fancy things. The line length gains are applied when copying or plotting the data.

NOTE: the linelength data are stored as an antenna based UV variable called phasem1, in radians. But note that this variable is not removed by any subsquent uvcat, and applying linecal twice is probably not a good thing.  

PARAMETERS

vis
Name of input visibility data file. No default. The visibility data must be in time order.
out
Optional name of the output calibration file. The default is to write the gain corrections into the input visibility file.
freq
Optional Frequency (in GHz) to use to convert a cable (in ms) measurement (in ns) to phasem1 (in radians) for linelength. Normally this option is not used, since phasem1 was derived by using the LO1 frequency. This option has been added for debugging the cable to phasem1 conversion. Usually this option does not make sense for CARMA as LO1 is doppler tracked and this freq= would not be. For SZA this is appropriate, as they do not doppler track. For SZA data freq=35.938 should be used. Default: not used, and phasem1 is used to build the gain table.


 

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