The uves_obs_scired recipe =============================================================== .. data:: uves_obs_scired Synopsis -------- Reduces a science frame Description ----------- 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 Constructor ----------- .. method:: cpl.Recipe("uves_obs_scired") :noindex: Create an object for the recipe uves_obs_scired. :: import cpl uves_obs_scired = cpl.Recipe("uves_obs_scired") Parameters ---------- .. py:attribute:: uves_obs_scired.param.clean_traps 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) [default=False]. .. py:attribute:: uves_obs_scired.param.debug Whether or not to save intermediate results to local directory (bool; default: False) [default=False]. .. py:attribute:: uves_obs_scired.param.plotter 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') [default="no"]. .. py:attribute:: uves_obs_scired.param.process_chip For RED arm data process the redl, redu, or both chip(s) (str; default: 'both') [default="both"]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.mmethod 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') [default="median"]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.npoints This is the number of columns in interorder space used to sample the background. (int; default: 82) [default=82]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.radiusy The height (in pixels) of the background sampling window is (2*radiusy + 1). This parameter is not corrected for binning. (int; default: 2) [default=2]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.sdegree Degree of interpolating splines. Currently only degree = 1 is supported (int; default: 1) [default=1]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.smoothx 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) [default=-1.0]. .. py:attribute:: uves_obs_scired.param.reduce.backsub.smoothy 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) [default=-1.0]. .. py:attribute:: uves_obs_scired.param.reduce.extract.best (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) [default=True]. .. py:attribute:: uves_obs_scired.param.reduce.extract.chunk 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) [default=32]. .. py:attribute:: uves_obs_scired.param.reduce.extract.kappa 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) [default=10.0]. .. py:attribute:: uves_obs_scired.param.reduce.extract.method 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') [default="optimal"]. .. py:attribute:: uves_obs_scired.param.reduce.extract.oversample 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) [default=-1]. .. py:attribute:: uves_obs_scired.param.reduce.extract.profile 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') [default="auto"]. .. py:attribute:: uves_obs_scired.param.reduce.extract.skymethod 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') [default="optimal"]. .. py:attribute:: uves_obs_scired.param.reduce.ffmethod 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, in which case reduce.rebin.scale should be set to true to ensure flux conservation (both for response and science data) (str; default: 'extract') [default="extract"]. .. py:attribute:: uves_obs_scired.param.reduce.merge 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') [default="optimal"]. .. py:attribute:: uves_obs_scired.param.reduce.merge_delt1 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`_ for more information about the recipe object. Bug reports ----------- Please report any problems to `Jonas M. Larsen `_. Alternatively, you may send a report to the `ESO User Support Department `_. Copyright --------- 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 .. codeauthor:: Jonas M. Larsen