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
       https://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
       https://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 5.5.7

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

fors_subtract_sky                                     5.5.7                                 FORS_SUBTRACT_SKY(7)