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fors_subtract_sky - Subtract sky from scientific spectra

FORS_SUBTRACT_SKY(7) fors recipes FORS_SUBTRACT_SKY(7)

NAME

fors_subtract_sky - Subtract sky from scientific spectra
 

SYNOPSIS

esorex fors_subtract_sky [OPTIONS] FILE.sof
 

DESCRIPTION

This recipe is used to subtract the sky emission from unrebinned slit spectra. This is obtained by robust fitting (i.e., excluding the signal from possible point-like objects in slit) of the emission along the CCD columns within each spectrum). This method doesn´t work if extended objects are in slit (it really destroys the object spectra), and is not applicable to LSS data. The input scientific frames are produced by the recipes fors_remove_bias and fors_flatfield.
This recipe cannot be applied to LSS or long-slit like data (MOS/MXU with all slits at the same offset). No automatic recipe is available for this.
Please refer to the FORS Pipeline User´s Manual for more details.
In the table below the MXU acronym can be alternatively read as MOS, and SCI as STD.
Input files:
 

DO category: Type: Explanation: Required:
SCIENCE_UNBIAS_MXU
or SCIENCE_UNFLAT_MXU
or STANDARD_UNBIAS_MXU
or STANDARD_UNFLAT_MXU Calib Frame with sky lines Y
CURV_COEFF_MXU Calib Spectral curvature Y
SLIT_LOCATION_MXU Calib Slit location on CCD Y
GRISM_TABLE Calib Grism table .
Output files:
 

DO category: Data type: Explanation:
UNMAPPED_SCI_MXU
or UNMAPPED_STD_MXU FITS image Sky subtracted scientific frame
UNMAPPED_SKY_SCI_MXU
or UNMAPPED_SKY_STD_MXU FITS image Subtracted sky frame
 
 
 

OPTIONS

--dispersion <float>
Expected spectral dispersion (Angstrom/pixel) (float; default: 0.0). The full name of this option for the EsoRex configuration file is fors.fors_subtract_sky.dispersion [default = 0.0].
--startwavelength <float>
Start wavelength in spectral extraction (float; default: 0.0). The full name of this option for the EsoRex configuration file is fors.fors_subtract_sky.startwavelength [default = 0.0].
--endwavelength <float>
End wavelength in spectral extraction (float; default: 0.0). The full name of this option for the EsoRex configuration file is fors.fors_subtract_sky.endwavelength [default = 0.0].
--cosmics <bool>
Eliminate cosmic rays hits (bool; default: False). The full name of this option for the EsoRex configuration file is fors.fors_subtract_sky.cosmics [default = False].
 
Note that it is possible to create a configuration file containing these options, along with suitable default values. Please refer to the details provided by the 'esorex --help' command.
 

SEE ALSO

The full documentation for the fors pipeline can be downloaded as a PDF file using the following URL:
ftp://ftp.eso.org/pub/dfs/pipelines/fors/fors-pipeline-manual-4.9.pdf
An overview over the existing ESO pipelines can be found on the web page http://www.eso.org/sci/software/pipelines/.
Basic documentation about the EsoRex program can be found at the esorex (1) man page.
It is possible to call the pipelines from python using the python-cpl package. See http://packages.python.org/python-cpl/index.html for further information.
The other recipes of the fors pipeline are fors_align_sky(7), fors_align_sky_lss(7), fors_bias(7), fors_calib(7), fors_config(7), fors_dark(7), fors_detect_objects(7), fors_detect_spectra(7), fors_extract(7), fors_extract_objects(7), fors_extract_slits(7), fors_flatfield(7), fors_img_science(7), fors_img_screen_flat(7), fors_img_sky_flat(7), fors_normalise_flat(7), fors_photometry(7), fors_pmos_calib(7), fors_pmos_extract(7), fors_pmos_science(7), fors_remove_bias(7), fors_resample(7), fors_science(7), fors_spec_mflat(7), fors_subtract_sky_lss(7), fors_sumflux(7), fors_trace_flat(7), fors_wave_calib(7), fors_wave_calib_lss(7), fors_zeropoint(7)
 

VERSION

fors_subtract_sky 5.3.23
 

AUTHOR

Carlo Izzo <usd-help@eso.org>
 

BUG REPORTS

Please report any problems to usd-help@eso.org. Alternatively, you may send a report to the ESO User Support Department <usd-help@eso.org>.
 

LICENSE

This file is currently part of the FORS Instrument Pipeline Copyright (C) 2002-2010 European Southern Observatory
 
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 
5.3.23 fors_subtract_sky