The Point Source Tune module converts the extracted spectrum from units of electrons per second to flux density (Jy). This module is for point source extractions. Extended Source Tune is used for extended sources. The conversion is only valid for the standard extraction width.
INPUTS
There are no user inputs for Point Source Tune.
OUTPUTS
Flux-calibrated spectrum (*.spect.tbl): The output of the module is the flux calibrated spectrum. It is written to the output table and displayed in the plot window. An ASCII version of the file is seen by clicking the View button.
DISCUSSION
This module applies absolute flux calibration to the one-dimensional spectral output file from Extract. For each separate spectral order in SL and LL and each Echelle order in SH and LH, Point Source Tune applies adjustments to the shape of the order and corrects by a scaling constant, in units of electrons/s/Jy, to convert the spectrum to units of Jy. The scaling and shape adjustments are contained in an input calibration file, fluxcon.tbl. This file contains the coefficients calculated by fitting an nth-order polynomial, where 1 ≤ n ≤ 5, to the Extract output of one or more calibration stars so that their observed IRS spectra are forced to match a model spectrum taken as truth. The ASCII output from Point Source Tune contains five columns containing the order number, wavelength in microns, flux in units of Jy, uncertainty in the flux measurement in Jy (currently not suited to derive signal-to-noise ratios), and any needed flags.
