SYSCAL System calibration.

Name

Format

Units

Measure

Comments

Columns

Key

ANTENNA_ID

Int Antenna identifier

FEED_ID

Int Feed identifier

SPECTRAL_WINDOW_ID

Int Spectral window identifier

TIME

Double s EPOCH Mid-point period when calibration data have been observed

INTERVAL

Double s Time interval

Data

(NUM_LOAD)

Int number Ncl of NCAL or TLOAD used

(CALLOAD)

Int( Ncl) List of the Ncl LOADs used

(FEFF)

Float( Nr) Forward efficiency

(AEFF)

Float( Nr) Aperture efficiency

(PHASE_DIFF)

Float rad Phase difference between receptor 0 and receptor 1

(SBGAIN)

Float Relative gain of LO1 sideband

(TAU)

Float( Nr) K Atmosheric optical depth

(TCAL)

Float( Nr) K Calibration temperature

(TRX)

Float( Nr) K Receiver temperature

(TSKY)

Float( Nr) K Sky temperature

(TSYS)

Float( Nr) K System temperature

(TANT)

Float( Nr) K Antenna temperature

(TANT_TSYS)

Float( Nr) Tant/Tsys

(PWVPATH)

Float( Nr) m Water vapor pathlength

(DPWVPATH)

Float( Nr) m K-1 Pathlength per K of radiometric emission

(FEFF_SPECTRUM)

Float( Nr, Nf) Forward efficiency spectrum

(SBGAIN_SPECTRUM)

Float( Nr, Nf) Relative gain spectrum

(TAU_SPECTRUM)

Float( Nr, Nf) Atmosheric optical depth spectrum

(TCAL_SPECTRUM)

Float( Nr, Nf) K Calibration temperature spectrum

(TRX_SPECTRUM)

Float( Nf) K Receiver temperature spectrum

(TSKY_SPECTRUM)

Float( Nr, Nf) Sky temperature spectrum

(TSYS_SPECTRUM)

Float( Nr, Nf) K System temperature spectrum

(TANT_SPECTRUM)

Float( Nr, Nf) K Antenna temperature spectrum

(TANT_TSYS_SPECTRUM)

Float( Nr, Nf) Tant/Tsys spectrum

(PWVPATH_SPECTRUM)

Float( Nf) m Water vapor pathlength spectrum

(DPWVPATH_SPECTRUM)

Float( Nf) m K-1 Pathlength increment spectrum

(NUM_POLY)

Int Series order Npoly

(NUM_POLY_FREQ)

Int Freq. series order Npolyf

(TIME_ORIGIN)

Double s EPOCH Origin for the polynomial

(FREQ_ORIGIN)

Double Hz FREQUENCY Origin of frequency expansion

(PHASE_CURVE)

Float( Nr, Npoly) rad Phase Polynomial Coefficients

(DELAY_CURVE)

Float( Nr, Npoly) s Delay polynomial coeff.

(AMPLI_CURVE)

Float( Nr, Npoly) Jy K-1 Amplitude polynomial coeff.

(BANDPASS_CURVE)

Float( Nr, Npolyf) Bandpass polynomial coeff.

Flags

(PHASEDIFF_FLAG)

Bool Flag for PHASEDIFF

(SBGAIN_FLAG)

Bool Flag for SBGAIN

(TAU_FLAG)

Bool Flag for TAU

(TCAL_FLAG)

Bool Flag for TCAL

(TRX_FLAG)

Bool Flag for TRX

(TSKY_FLAG)

Bool Flag for TSYS

(TSYS_FLAG)

Bool Flag for TSYS

(TANT_FLAG)

Bool Flag for TANT

(TANT_TSYS_FLAG)

Bool Flag for Tant/Tsys

(PWVPATH_FLAG)

Bool Flag for PWVPATH

Notes: This table contains time-variable calibration measurements for each antenna, as indexed on feed and spectral window. Nr is the number of receptors and Nf the number of frequency channels.
Note that all the items in the data section are optional. However, at least one non-key item must be specified for a given row in this table.
ANTENNA_ID
Antenna identifier, as indexed from an element in the ANTENNA_ARRAY collection in the CONFIG_DESCRIPTION table.
FEED_ID
Feed identifier, as indexed from an element in the FEED_LISTcollection in the the CONFIG_DESCRIPTION table.
SPECTRAL_WINDOW_ID
Spectral window identifier. In general this will be associated to spectral window identifiers corresponding to low spectral resolutions. .
TIME
Mid-point of the time interval over which the data in the row are valid. Require to use the same TIME Measure reference as in MAIN
INTERVAL
Time interval
NUM_LOAD
Number of loads Ncl used for this calibration. (e.g. 2 for the determination of TRX using a a cold and a hot load, 1 for determination of TCAL, a hot load when using the chopper wheel method, ...)
CALLOAD
List of the Ncl loads used for this calibration. (e.g. 2 for the determination of TRX using a a cold and a hot load, 1 for determination of TCAL, a hot load when using the chopper wheel method, ...)
FEFF
Fraction of the beam volume looking at the sky.  
AEFF
Aperture efficiency.  
PHASE_DIFF
Phase difference between receptor 0 and receptor 1.
SBGAIN
Sideband gain spectrum. Actual normalization to be defined.
TAU
Average opacity
TCAL
Calibration temperature (temperature used to convert the raw signals to Ta* scale.)  
TRX
Receiver temperature.  
TSKY
Sky temperature  
TSYS
System temperature  
TANT
Antenna temperature
TANT_TSYS
Antenna temperature over system temperature
PWVPATH
Water vapor pathlength  
DPWVPATH
Water vapor pathlength increment per K of radiometric emission  
FEFF_SPECTRUM
Fraction of the beam volume spectrum.  
SBGAIN_SPECTRUM
Sideband gain spectrum. The other SPECTRAL_WINDOW_IDfor the other sideband is know via ASSOC_SPW_ID 
TAU_SPECTRUM
Opacity spectrum
TCAL_SPECTRUM
  Temperature used to convert the raw signals to Ta* scale
TRX_SPECTRUM
Receiver temperature spectrum. Frequency dependency mandatory for ALMA  
TSKY_SPECTRUM
Sky temperature spectrum  
TSYS_SPECTRUM
System temperature spectrum  
TANT_SPECTRUM
Antenna temperature spectrum    
TANT_TSYS_SPECTRUM
Antenna temperature over system temperature spectrum
PWVPATH_SPECTRUM
Water vapor pathlength spectrum
DPWVPATH_SPECTRUM
Water vapor pathlength increment spectrum per K of radiometric emission
TAU_SPECTRUM
Atmosheric optical depth spectrum
NUM_POLY
Series order Npoly
NUM_POLY_FREQ
Frequencies series order Npolyf
TIME_ORIGIN
Origin of time expansion
FREQ_ORIGIN
Origin of frequency expansion
PHASE_CURVE
Provisional Phase polynomial coefficients
DELAY_CURVE
Provisional Delay polynomial coefficients
AMPLI_CURVE
Provisional Amplitude polynomial coefficients
BANDPASS_CURVE
Provisional bandpass polynomial coefficients
PHASEDIFF_FLAG
True if PHASE_DIFF flagged
PHASEDIFF_FLAG
True if PHASE_DIFF flagged
SBGAIN_FLAG
True if SBGAIN flagged
TAU_FLAG
True if TAU flagged
TCAL_FLAG
True if TCAL flagged
TRX_FLAG
True if TRX flagged
TSKY_FLAG
True if TSKY flagged
TSYS_FLAG
True if TSYS flagged
TANT_FLAG
True if TANT flagged
TANT_TSYS_FLAG
True if TANT_TSYS flagged
PWVPATH_FLAG
True if PWVPATH flagged