Content-type: text/html Manpage of tmcal

tmcal

Section: User Commands (1)
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NAME

tmcal - Gain/phase/polarization calibration for SMA data.  

PERSON RESPONSIBLE

rjs  

CATEGORIES

calibration  

DESCRIPTION

tmcal is a MIRIAD task which determines calibration corrections (both antenna gains and instrumental polarisation characteristics).  

PARAMETERS

vis
Input visibility data file. No default. The visibility data must be in time order.
select
Standard uv selection. Default is all data.
line
Standard line-type specification. Multiple channels can be given. Generally it is better to give multiple channels, rather than averaging them into a `channel-0'. The default is all the channel data (or all the wide data, if there is no channel data).
flux
The values of the I,Q,U Stokes parameters. If no values are given, and it is a source known to tmcal, tmcal uses its known flux as the default. If tmcal does not know the source, the flux is determined by assuming that the rms gain amplitude is 1. For a planet, the values are interpreted as brightness temperature in Kelvin (planets are assumed to be unpolarised). Otherwise the values are assumed to be in Janskys.

If the option `qusolve' is used, the given fluxes for Q and U are used as the initial estimates.

refant
The reference antenna. Default is 1. The reference antenna needs to be present throughout the observation, and so needs to be chosen with some care. Any solution intervals where the reference antenna is missing are discarded.
minants
The minimum number of antenna that must be present before a solution is attempted. Default is 2.
interval
This gives the solution interval, in minutes. Antenna gains are assumed to be constant over the solution interval.
tol
Error tolerance. The default is 0.001, which should be adequate.
options
These options determine what TMCAL solves for. Several options can be given,separated by commas.
  nopass     Do not apply any passband calibration.
  qusolve    Solve for Q and U fluxes. Good parallactic
             angle coverage is required for this.
  twoleak    Solve for a "two part" leakage solution,
  onegain    Solve for a single antenna gain, which is assumed to be
             independent of polarisation. When time-multiplexing of a single
             feed is used to measure two states (e.g. R and L), then it should
             be accurate to assume the antenna gains to R and L are the same.


 

Index

NAME
PERSON RESPONSIBLE
CATEGORIES
DESCRIPTION
PARAMETERS

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Time: 18:35:38 GMT, July 05, 2011