sdfit – Fit a spectral line – single dish task

Description

Task sdfit is a basic line-fitter for single-dish spectra. It assumes that the spectra have been calibrated in sdcal or sdreduce.

Parameters

Title

Parameter	Default	Description
infile	''
antenna	int(0)
fluxunit	''	units of the flux ['K' or 'Jy'] (''=current)
telescopeparam	''
field	''
spw	''
restfreq	''
frame	''	frequency reference frame ['LSRK', 'TOPO', 'LSRD', 'BARY', 'GALACTO', 'LGROUP', or 'CMB'] (''=current)
doppler	''	doppler convention ['RADIO', 'OPTICAL', 'Z', 'BETA', or 'GAMMA'] (''=current).
scan	''
pol	''
timeaverage	False	average spectra over time [True, False] (see examples in help)
tweight	'tintsys'	weighting for time averaging ['tintsys', 'tsys', 'tint', 'var', or 'median']
scanaverage	False	average spectra within a scan number [True, False] (see examples in help)
polaverage	False	average spectra over polarizations [True, False]
pweight	'tsys'	weighting for polarization averaging ['tsys' or 'var']
fitfunc	'gauss'	function for fitting ['gauss', 'lorentz']
fitmode	'auto'	mode for fitting ['auto', 'list', or 'interact']
nfit	numpy.array( [  ] )
thresh	float(5.0)
min_nchan	int(3)
avg_limit	int(4)
box_size	float(0.2)
edge	numpy.array( [ int(0) ] )
outfile	''
overwrite	False	overwrite the output file if already exists [True, False]
plotlevel	int(0)
xstat	[ ]

Parameter Explanations

infile

''

name of input SD dataset

antenna

int(0)

select an antenna name or ID, e.g. 'PM03' (only effective for MS input)

fluxunit

''

units of the flux (''=current)

telescopeparam

''

parameters of telescope for flux conversion (see examples in help)

field

''

select data by field IDs and names, e.g. '3C2*' (''=all)

spw

''

select data by IF IDs (spectral windows), e.g. '3,5,7' (''=all)

restfreq

''

the rest frequency, e.g. '1.41GHz' (default unit: Hz) (see examples in help)

frame

''

frequency reference frame (''=current)

doppler

''

doppler convention (''=current). Effective only when spw selection is in velocity unit.

scan

''

select data by scan numbers, e.g. '21~23' (''=all)

pol

''

select data by polarization IDs, e.g. '0,1' (''=all)

timeaverage

False

average spectra over time (see examples in help)

tweight

'tintsys'

weighting for time averaging

scanaverage

False

average spectra within a scan number (see examples in help)

polaverage

False

average spectra over polarizations

pweight

'tsys'

weighting for polarization averaging

fitfunc

'gauss'

function for fitting

fitmode

'auto'

mode for fitting

nfit

numpy.array( [  ] )

list of number of gaussian/lorentzian lines to fit in in maskline region (ignored when fitmode=”auto”)

thresh

float(5.0)

S/N threshold for linefinder

min_nchan

int(3)

minimum number of consecutive channels for linefinder

avg_limit

int(4)

channel averaging for broad lines

box_size

float(0.2)

running mean box size

edge

numpy.array( [ int(0) ] )

channels to drop at beginning and end of spectrum

outfile

''

name of output file (See a WARNING in help)

overwrite

False

overwrite the output file if already exists

plotlevel

int(0)

control for plotting of results (see examples in help)

xstat

[ ]

RETURN ONLY: a Python dictionary of line statistics