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sd.apexcal - Function

5.1.1 Calibration function specific for APEX data
Description

This method is properly defined for calibration of APEX data. Input data must be a scantable object. The calibration scheme is essentially same as ALMA data,

T* = T  ON----OF-F-,
 a    sys   OF F

where Ta* is an antenna temperature, Tsys is a system temperature, ON and OFF are raw (uncalibrated) spectral data that correspond to on-source and off-source position, respectively. Only difference with ALMA calibration is that Tsys doesn’t provided. Instead, it is computed from a calibration temperature and two calibration scans: a blank sky and a load with known temperature. The OFF scan is linearly interpolated in time if it exists in the vicinity of target ON scan. The calmode argument specifies calibration mode. Supported calibration modes are ’ps’ (position switch) and ’fs’ (frequency switch). The ’ps’ includes calibration for nutator switching as well as classical position switching.

Arguments





Inputs

scantab

input data as a scantable

allowed:

scantable

Default:

scannos

a list of scan numbers to be calibrated

allowed:

(list of) integer, string

Default:

[] (all data)

calmode

Calibration mode

allowed:

string (’ps’, ’fs’, ’none’)

Default:

’none’

verify

Verify calibration if True

allowed:

bool

Default:

False





Returns
scantable

Example

    s=sd.scantable(’alma-scans.asap’,average=False,getpt=True)  
    scal=sd.apexcal(s,calmode=’ps’)


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