uves_obs_scired - Reduces a science frame
esorex uves_obs_scired [OPTIONS] FILE.sof
This recipe reduces a science frame (SCIENCE_BLUE or SCIENCE_RED,
or SCI_POINT_BLUE or SCI_POINT_RED, or SCI_EXTND_BLUE or SCI_EXTND_RED or
SCI_SLICER_BLUE or SCI_SLICER_RED) using a combination (depending on recipe
parameters and provided input frames) of the steps:
- bias subtraction,
- dark subtraction,
- background subtraction,
- extraction/cosmic ray removal,
- flat field correction,
- wavelength rebinning,
- sky subtraction,
- order merging,
- response correction (if response curve is provided).
Additional input for this recipe are: order table(s) for each
chip, ORDER_TABLE_xxxx (where xxxx=BLUE, REDL, REDU), line table(s) for each
chip, LINE_TABLE_xxxx, a master bias frame, MASTER_BIAS_xxxx, a master flat,
MASTER_FLAT_xxxx, optionally an instrument response table,
INSTR_RESPONSE_FINE_xxx, optionally an master response table,
MASTER_RESPONSE_xxx, and optionally a table describing the atmospheric
extinction, EXTCOEFF_TABLE.
For each chip (xxxx = BLUE, REDL, REDU) the recipe produces a
combination of the products:
´RED_SCIENCE_xxxx´ Reduced science spectrum
´MERGED_SCIENCE_xxxx´ Merged spectrum, no sky subtraction
´WCALIB_SCIENCE_xxxx´ Extracted, wavelength calibrated frame in
(wavelength, order) space
´WCALIB_FF_SCIENCE_xxxx´ Extracted, flat-fielded, wave.cal.
frame in
(wavelength, order) space
(Only if flatfielding done)
´WCALIB_FLAT_OBJ_xxxx´ Extracted, wavelength calibrated flat
field
in (wavelength, order) space
(Only if flatfielding done)
´ERRORBAR_SCIENCE_xxxx´ Error bars of
´RED_SCIENCE_xxxx´
´VARIANCE_SCIENCE_xxxx´ Variance of extracted, flatfielded
object in
(pixel, order) space
´ORDER_TRACE_xxxx´ Table describing the spatial profile
´FLUXCAL_SCIENCE_xxxx´ Flux-calibrated science spectrum
´FLUXCAL_ERROR_xxxx´ Error bars of
´FLUXCAL_SCIENCE_xxxx´
´BKG_SCI_xxxx´ The subtracted background image
´CRMASK_xxxx´ List of cosmic ray hits
´MERGED_SKY_xxxx´ The merged sky spectrum
´EXT_2D_SCIENCE_xxxx´ The 2d extracted spectrum
´FF2D_SCIENCE_xxxx´ The 2d extracted, flat-fielded spectrum
´WCAL2D_SCIENCE_xxxx´ The 2d extracted, flat-fielded, wave.cal.
spectrum
´MER2D_SCIENCE_xxxx´ The 2d reduced, flux-calibrated (if
possible)
science spectrum
- --clean_traps
<bool>
- Clean detector traps. If TRUE detector traps are interpolated.The bad
pixels are replaced by the average of thenearest good pixels in the same
column, or simply marked as bad. The positions of bad pixels are
hard-coded (as function of UVES chip). (bool; default: False). The full
name of this option for the EsoRex configuration file is
uves_obs_scired.clean_traps [default = False].
- --debug
<bool>
- Whether or not to save intermediate results to local directory (bool;
default: False). The full name of this option for the EsoRex configuration
file is uves.debug [default = False].
- --plotter
<str>
- Any plots produced by the recipe are redirected to the command specified
by this parameter. The plotting command must contain the substring
´gnuplot´ and must be able to parse gnuplot syntax on its
standard input. Valid examples of such a command may include
´gnuplot -persist´ and ´cat >
mygnuplot$$.gp´. A finer control of the plotting options can be
obtained by writing an executable script, e.g. my_gnuplot.pl, that
executes gnuplot after setting the desired gnuplot options (e.g. set
terminal pslatex color). To turn off plotting, set this parameter to
´no´ (str; default: ´no´). The full name of
this option for the EsoRex configuration file is uves.plotter
[default = no].
- --process_chip
<str>
- For RED arm data process the redl, redu, or both chip(s) (str; default:
´both´). The full name of this option for the EsoRex
configuration file is uves.process_chip [default =
both].
- --reduce.backsub.mmethod
<str>
- Background measuring method. If equal to ´median´ the
background is sampled using the median of a subwindow. If
´minimum´, the subwindow minimum value is used. If
´no´, no background subtraction is done. (str; default:
´median´). The full name of this option for the EsoRex
configuration file is uves_obs_scired.reduce.backsub.mmethod
[default = median].
- --reduce.backsub.npoints
<int>
- This is the number of columns in interorder space used to sample the
background. (int; default: 82). The full name of this option for the
EsoRex configuration file is uves_obs_scired.reduce.backsub.npoints
[default = 82].
- --reduce.backsub.radiusy
<int>
- The height (in pixels) of the background sampling window is (2*radiusy +
1). This parameter is not corrected for binning. (int; default: 2). The
full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.backsub.radiusy [default = 2].
- --reduce.backsub.sdegree
<int>
- Degree of interpolating splines. Currently only degree = 1 is supported
(int; default: 1). The full name of this option for the EsoRex
configuration file is uves_obs_scired.reduce.backsub.sdegree
[default = 1].
- --reduce.backsub.smoothx
<float>
- If spline interpolation is used to measure the background, the x-radius of
the post-smoothing window is (smoothx * image_width). Here,
´image_width´ is the image width after binning. If negative,
the default values are used: (25.0/4096) for blue flat-field frames,
(50.0/4096) for red flat-field frames, (300.0/4096) for blue science
frames and (300.0/4096) for red science frames. (float; default: -1.0).
The full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.backsub.smoothx [default =
-1.0].
- --reduce.backsub.smoothy
<float>
- If spline interpolation is used to measure the background, the y-radius of
the post-smoothing window is (smoothy * image_height). Here,
´image_height´ is the image height after binning. If
negative, the default values are used: (100.0/2048) for blue flat-field
frames, (300.0/2048) for red flat-field frames, (200.0/2048) for blue
science frames and (500.0/2048) for red science frames. (float; default:
-1.0). The full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.backsub.smoothy [default =
-1.0].
- (optimal extraction only) If false (fastest), the spectrum is extracted
only once. If true (best), the spectrum is extracted twice, the second
time using improved variance estimates based on the first iteration.
Better variance estimates slightly improve the obtained signal to noise
but at the cost of increased execution time (bool; default: True). The
full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.extract.best [default = True].
- In optimal extraction mode, the chunk size (in pixels) used for fitting
the analytical profile (a fit of the analytical profile to single bins
would suffer from low statistics). (int; default: 32). The full name of
this option for the EsoRex configuration file is
uves_obs_scired.reduce.extract.chunk [default = 32].
- In optimal extraction mode, this is the threshold for bad (i.e. hot/cold)
pixel rejection. If a pixel deviates more than kappa*sigma (where sigma is
the uncertainty of the pixel flux) from the inferred spatial profile, its
weight is set to zero. Range: [-1,100]. If this parameter is negative, no
rejection is performed. (float; default: 10.0). The full name of this
option for the EsoRex configuration file is
uves_obs_scired.reduce.extract.kappa [default = 10.0].
- Extraction method. (2d/optimal not supported by uves_cal_wavecal, weighted
supported only by uves_cal_wavecal, 2d not supported by uves_cal_response)
(str; default: ´optimal´). The full name of this option for
the EsoRex configuration file is
uves_obs_scired.reduce.extract.method [default =
optimal].
- The oversampling factor used for the virtual resampling algorithm. If
negative, the value 5 is used for S/N <=200, and the value 10 is used
if the estimated S/N is > 200 (int; default: -1). The full name of this
option for the EsoRex configuration file is
uves_obs_scired.reduce.extract.oversample [default =
-1].
- In optimal extraction mode, the kind of profile to use.
´gauss´ gives a Gaussian profile, ´moffat´
gives a Moffat profile with beta=4 and a possible linear sky contribution.
´virtual´ uses a virtual resampling algorithm (i.e. measures
and uses the actual object profile). ´constant´ assumes a
constant spatial profile and allows optimal extraction of wavelength
calibration frames. ´auto´ will automatically select the
best method based on the estimated S/N of the object. For low S/N,
´moffat´ or ´gauss´ are recommended (for
robustness). For high S/N, ´virtual´ is recommended (for
accuracy). In the case of virtual resampling, a precise determination of
the order positions is required; therefore the order-definition is
repeated using the (assumed non-low S/N) science frame (str; default:
´auto´). The full name of this option for the EsoRex
configuration file is uves_obs_scired.reduce.extract.profile
[default = auto].
- In optimal extraction mode, the sky subtraction method to use.
´median´ estimates the sky as the median of pixels along the
slit (ignoring pixels close to the object), whereas
´optimal´ does a chi square minimization along the slit to
obtain the best combined object and sky levels. The optimal method gives
the most accurate sky determination but is also a bit slower than the
median method (str; default: ´optimal´). The full name of
this option for the EsoRex configuration file is
uves_obs_scired.reduce.extract.skymethod [default =
optimal].
- --reduce.ffmethod
<str>
- Flat-fielding method. If set to ´pixel´, flat-fielding is
done in pixel-pixel space (before extraction); if set to
´extract´, flat- fielding is performed in pixel-order space
(i.e. after extraction). If set to ´no´, no flat-field
correction is done (str; default: ´extract´). The full name
of this option for the EsoRex configuration file is
uves_obs_scired.reduce.ffmethod [default = extract].
- --reduce.merge
<str>
- Order merging method. If ´optimal´, the flux in the
overlapping region is set to the (optimally computed, using the
uncertainties) average of single order spectra. If ´sum´,
the flux in the overlapping region is computed as the sum of the single
order spectra. If ´noappend´ the spectrum is simply rebinned
but not merged.If flat-fielding is done, method ´optimal´ is
recommended, otherwise ´sum´. (str; default:
´optimal´). The full name of this option for the EsoRex
configuration file is uves_obs_scired.reduce.merge [default =
optimal].
- --reduce.merge_delt1
<float>
- Order merging left hand (short wavelength) cut. To reduce the amount of
order overlapping regions we allow to cut short and long wavelength
ranges. This may reduce the ripple possibly introduced by the order
merging. Suggested values are: 10 (W<=390), 12 (390<W<=437,
520<W<=564), 14 (437<W<=520, 564<W) (float; default: 0.0).
The full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.merge_delt1 [default = 0.0].
- --reduce.merge_delt2
<float>
- Order merging right hand (long wavelength) cut. To reduce the amount of
order overlapping regions we allow to cut short and long wavelength
ranges. This may reduce the ripple possibly introduced by the order
merging. Suggested values is 4 (float; default: 0.0). The full name of
this option for the EsoRex configuration file is
uves_obs_scired.reduce.merge_delt2 [default = 0.0].
- --reduce.objoffset
<float>
- Offset (in pixels) of extraction slit with respect to center of order.
This parameter applies to linear/average/optimal extraction. For
linear/average extraction, if the related parameter objslit is negative,
the offset is automatically determined by measuring the actual object
position. (float; default: 0.0). The full name of this option for the
EsoRex configuration file is uves_obs_scired.reduce.objoffset
[default = 0.0].
- --reduce.objslit
<float>
- Object window size (in pixels). This must be less than the total slit
length. If negative, the default value (half of full slit length) is used.
The upper and lower sky windows are defined as the part of the full slit
(if any) outside the object window. The center of the object window is
determined by the offset parameter. This parameter does not apply to
optimal extraction. (float; default: -1.0). The full name of this option
for the EsoRex configuration file is uves_obs_scired.reduce.objslit
[default = -1.0].
- --reduce.rebin.scale
<bool>
- Whether or not to multiply by the factor dx/dlambda (pixels per
wavelength) during the rebinning. This option is disabled as default in
concordance with the method used in the MIDAS pipeline. This option should
be set to true to convert the observed flux (in pixel-space) to a flux per
wavelength (in wavelength-space). (bool; default: False). The full name of
this option for the EsoRex configuration file is
uves_obs_scired.reduce.rebin.scale [default = False].
- --reduce.rebin.wavestep
<float>
- The bin size used for REDU data (in w.l.u.) in wavelength space. If
negative, a step size of 2/3 * ( average pixel size ) is used. (float;
default: -1.0). The full name of this option for the EsoRex configuration
file is uves_obs_scired.reduce.rebin.wavestep [default =
-1.0].
- --reduce.rebin.wavestep_redu
<float>
- The bin size used for REDU data (in w.l.u.) in wavelength space. If
negative, a step size of 2/3 * ( average pixel size ) is used. (float;
default: -1.0). The full name of this option for the EsoRex configuration
file is uves_obs_scired.reduce.rebin.wavestep_redu [default =
-1.0].
- --reduce.skysub
<bool>
- Do sky-subtraction (only applicable to linear and average extractions)?
(bool; default: True). The full name of this option for the EsoRex
configuration file is uves_obs_scired.reduce.skysub [default =
True].
- --reduce.slitlength
<float>
- Extraction slit length (in pixels). If negative, the value inferred from
the raw frame header is used (float; default: -1.0). The full name of this
option for the EsoRex configuration file is
uves_obs_scired.reduce.slitlength [default = -1.0].
- --reduce.tiltcorr
<bool>
- If enabled (recommended), the provided dispersion solutions obtained at
different slit positions are interpolated linearly at the actually
measured position of the object/sky. Line tilt correction is currently not
supported for 2d extraction, in which case the dispersion solution
obtained at the middle of the slit is always used. (bool; default: True).
The full name of this option for the EsoRex configuration file is
uves_obs_scired.reduce.tiltcorr [default = True].
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.
The full documentation for the uves pipeline can be downloaded as
a PDF file using the following URL:
- ftp://ftp.eso.org/pub/dfs/pipelines/uves/uves-pipeline-manual-6.1.3.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 uves pipeline are
flames_cal_mkmaster(7), flames_cal_orderpos(7),
flames_cal_predict(7), flames_cal_prep_sff_ofpos(7),
flames_cal_wavecal(7), flames_obs_redchain(7),
flames_obs_scired(7), flames_utl_unpack(7),
uves_cal_cd_align(7), uves_cal_mbias(7),
uves_cal_mdark(7), uves_cal_mflat(7),
uves_cal_mflat_combine(7), uves_cal_mkmaster(7),
uves_cal_orderpos(7), uves_cal_predict(7),
uves_cal_response(7), uves_cal_tflat(7),
uves_cal_wavecal(7), uves_obs_redchain(7),
uves_utl_ima_arith(7), uves_utl_remove_crh_single(7)
Jonas M. Larsen <cpl@eso.org>
Please report any problems to cpl@eso.org. Alternatively, you may
send a report to the ESO User Support Department
<usd-help@eso.org>.
This file is part of the FLAMES/UVES Pipeline Copyright (C) 2004,
2005, 2006, 2007 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 02111-1307 USA