What's the difference between Antenna1 and Antenna2? Axis definitions in plotms: Difference between revisions

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How can one find out what integer corresponds to which correlation???
How can one find out what integer corresponds to which correlation???


== Antenna1 ==
== Antenna1, Antenna2 ==
For plotting baseline-based quantities like amplitude, either Antenna1 or Antenna2 must be chosen. Antenna1 is the first antenna in a baseline pair; for example, for baseline 2-4, Antenna1 = 2. Antennae are numbered according to the antenna IDs listed in [[listobs]].
For plotting baseline-based quantities like amplitude, either Antenna1 or Antenna2 must be chosen. Antenna1 is the first antenna in a baseline pair; for example, for baseline 2-4, Antenna1 = 2. Antenna2 is the second antenna in a baseline pair; for example, for baseline 2-4, Antenna2 = 4. Antennae are numbered according to the antenna IDs listed in [[listobs]].
 
== Antenna2 ==
For plotting baseline-based quantities like amplitude, either Antenna1 or Antenna2 must be chosen. Antenna2 is the second antenna in a baseline pair; for example, for baseline 2-4, Antenna2 = 4. Antennae are numbered according to the antenna IDs listed in [[listobs]].


== Antenna ==
== Antenna ==

Revision as of 23:51, 18 February 2010

Plotms is a powerful tool for visualizing your measurement set, and provides you with lots of choices for X- and Y- Axes. It's not always clear what the choices mean, so below are some explanations.

Scan

The scan number, as listed by listobs.

Field

The field number, as listed by listobs. Typically, each source should have a different field number.

Time

The time at which the visibility was observed, given in terms of calendar year (yyyy/mm/dd/hh:mm:ss.ss)

Time_interval

???

Is this integration time?? In what units??

???

Spw

The spectral window number (analogous to what VLA users know as an IF). The characteristics of each spectral window are listed in listobs.

Channel

The frequency channel number.

Frequency

Frequency in units of GHz. The exact definition of this frequency can be set by parameters in the Trans tab of plotms.

Corr

Correlations (e.g., RR, LL), which have been assigned integer IDs

???

By what scheme???

How can one find out what integer corresponds to which correlation???

Antenna1, Antenna2

For plotting baseline-based quantities like amplitude, either Antenna1 or Antenna2 must be chosen. Antenna1 is the first antenna in a baseline pair; for example, for baseline 2-4, Antenna1 = 2. Antenna2 is the second antenna in a baseline pair; for example, for baseline 2-4, Antenna2 = 4. Antennae are numbered according to the antenna IDs listed in listobs.

Antenna

For plotting antenna-based quantities like elevation, use just plain Antenna. Antennae are numbered according to the antenna IDs listed in listobs.

Baseline

The baseline number, where baseline number is defined as ???

???

UVDist

Projected baseline separation in units of meters.

???

Is this true?

???

UVDist_L

Projected baseline separations in units of the observing wavelength (lambda, not kilolambda).

U, V, W

Velocity

Amp

Data amplitudes in units of Jansky.

Phase

Data phases in units of degrees.

Real

Real part of the visibility in units of Jansky.

Imag

Imaginary part of the visibility in units of Jansky.

Flag

Azimuth

Elevation

HourAngle

ParAngle

Ant-Azimuth

Ant-Elevation

Ant-ParAng

Row

FlagRow


Last checked in CASA Version 3.0.1 (r10380).