The muse_scibasic recipe =============================================================== .. data:: muse_scibasic Synopsis -------- Remove the instrumental signature from the data of each CCD and convert them from an image into a pixel table. Description ----------- Processing handles each raw input image separately: it trims the raw data and records the overscan statistics, subtracts the bias (taking account of the overscan, if --overscan is not "none"), optionally detects cosmic rays (note that by default cosmic ray rejection is handled in the post processing recipes while the data is reformatted into a datacube, so that the default setting is cr="none" here), converts the images from adu to count, subtracts the dark, divides by the flat-field, and (optionally) propagates the integrated flux value from the twilight-sky cube. The reduced image is then saved (if --saveimage=true). The input calibrations geometry table, trace table, and wavelength calibration table are used to assign 3D coordinates to each CCD-based pixel, thereby creating a pixel table for each exposure. If --skylines contains one or more wavelengths for (bright and isolated) sky emission lines, these lines are used to correct the wavelength calibration using an offset. The data is then cut to a useful wavelength range (if --crop=true). If an ILLUM exposure was given as input, it is then used to correct the relative illumination between all slices of one IFU. For this, the data of each slice is multiplied by the normalized median flux of that slice in the ILLUM exposure. As last step, the data is divided by the normalized twilight cube (if given), using the 3D coordinate of each pixel in the pixel table to interpolate the twilight correction onto the data. This pre-reduced pixel table for each exposure is then saved to disk. Constructor ----------- .. method:: cpl.Recipe("muse_scibasic") :noindex: Create an object for the recipe muse_scibasic. :: import cpl muse_scibasic = cpl.Recipe("muse_scibasic") Parameters ---------- .. py:attribute:: muse_scibasic.param.nifu IFU to handle. If set to 0, all IFUs are processed serially. If set to -1, all IFUs are processed in parallel. (int; default: 0) [default=0]. .. py:attribute:: muse_scibasic.param.overscan If this is "none", stop when detecting discrepant overscan levels (see ovscsigma), for "offset" it assumes that the mean overscan level represents the real offset in the bias levels of the exposures involved, and adjusts the data accordingly; for "vpoly", a polynomial is fit to the vertical overscan and subtracted from the whole quadrant. (str; default: 'vpoly') [default="vpoly"]. .. py:attribute:: muse_scibasic.param.ovscreject This influences how values are rejected when computing overscan statistics. Either no rejection at all ("none"), rejection using the DCR algorithm ("dcr"), or rejection using an iterative constant fit ("fit"). (str; default: 'dcr') [default="dcr"]. .. py:attribute:: muse_scibasic.param.ovscsigma If the deviation of mean overscan levels between a raw input image and the reference image is higher than |ovscsigma x stdev|, stop the processing. If overscan="vpoly", this is used as sigma rejection level for the iterative polynomial fit (the level comparison is then done afterwards with |100 x stdev| to guard against incompatible settings). Has no effect for overscan="offset". (float; default: 30.0) [default=30.0]. .. py:attribute:: muse_scibasic.param.ovscignore The number of pixels of the overscan adjacent to the data section of the CCD that are ignored when computing statistics or fits. (int; default: 3) [default=3]. .. py:attribute:: muse_scibasic.param.crop Automatically crop the output pixel tables in wavelength depending on the expected useful wavelength range of the active instrument mode (4750-9350 Angstrom for nominal mode and NFM, 4700-9350 Angstrom for nominal AO mode, and 4600-9350 Angstrom for the extended modes). (bool; default: True) [default=True]. .. py:attribute:: muse_scibasic.param.cr Type of cosmic ray cleaning to use (for quick-look data processing). (str; default: 'none') [default="none"]. .. py:attribute:: muse_scibasic.param.xbox Search box size in x. Only used if cr=dcr. (int; default: 15) [default=15]. .. py:attribute:: muse_scibasic.param.ybox Search box size in y. Only used if cr=dcr. (int; default: 40) [default=40]. .. py:attribute:: muse_scibasic.param.passes Maximum number of cleaning passes. Only used if cr=dcr. (int; default: 2) [default=2]. .. py:attribute:: muse_scibasic.param.thres Threshold for detection gap in factors of standard deviation. Only used if cr=dcr. (float; default: 5.8) [default=5.8]. .. py:attribute:: muse_scibasic.param.combine Type of combination to use. Note that in most cases, science exposures cannot easily be combined on the CCD level, so this should usually be kept as "none"! This does not pay attention about the type of input data, and will combine all raw inputs! (str; default: 'none') [default="none"]. .. py:attribute:: muse_scibasic.param.nlow Number of minimum pixels to reject with minmax (int; default: 1) [default=1]. .. py:attribute:: muse_scibasic.param.nhigh Number of maximum pixels to reject with minmax (int; default: 1) [default=1]. .. py:attribute:: muse_scibasic.param.nkeep Number of pixels to keep with minmax (int; default: 1) [default=1]. .. py:attribute:: muse_scibasic.param.lsigma Low sigma for pixel rejection with sigclip (float; default: 3.0) [default=3.0]. .. py:attribute:: muse_scibasic.param.hsigma High sigma for pixel rejection with sigclip (float; default: 3.0) [default=3.0]. .. py:attribute:: muse_scibasic.param.scale Scale the individual images to a common exposure time before combining them. (bool; default: True) [default=True]. .. py:attribute:: muse_scibasic.param.saveimage Save the pre-processed CCD-based image of each input exposure before it is transformed into a pixel table. (bool; default: True) [default=True]. .. py:attribute:: muse_scibasic.param.skylines List of wavelengths of sky emission lines (in Angstrom) to use as reference for wavelength offset correction using a Gaussian fit. It can contain multiple (isolated) lines, as comma-separated list, individual shifts are then combined into one weighted average offset. Set to "none" to deactivate. (str; default: '5577.339,6300.304') [default="5577.339,6300.304"]. .. py:attribute:: muse_scibasic.param.skyhalfwidth Half-width of the extraction box (in Angstrom) around each sky emission line. (float; default: 5.0) [default=5.0]. .. py:attribute:: muse_scibasic.param.skybinsize Size of the bins (in Angstrom per pixel) for the intermediate spectrum to do the Gaussian fit to each sky emission line. (float; default: 0.1) [default=0.1]. .. py:attribute:: muse_scibasic.param.skyreject Sigma clipping parameters for the intermediate spectrum to do the Gaussian fit to each sky emission line. Up to three comma-separated numbers can be given, which are interpreted as high sigma-clipping limit (float), low limit (float), and number of iterations (integer), respectively. (str; default: '15.,15.,1') [default="15.,15.,1"]. .. py:attribute:: muse_scibasic.param.resample Resample the input science data into 2D spectral images using all supplied calibrations for a visual check. Note that the image produced will show small wiggles even when the input calibrations are good and were applied successfully! (bool; default: False) [default=False]. .. py:attribute:: muse_scibasic.param.dlambda Wavelength step (in Angstrom per pixel) to use for resampling. (float; default: 1.25) [default=1.25]. .. py:attribute:: muse_scibasic.param.merge Merge output products from different IFUs into a common file. (bool; default: False) [default=False]. The following code snippet shows the default settings for the available parameters. :: import cpl muse_scibasic = cpl.Recipe("muse_scibasic") muse_scibasic.param.nifu = 0 muse_scibasic.param.overscan = "vpoly" muse_scibasic.param.ovscreject = "dcr" muse_scibasic.param.ovscsigma = 30.0 muse_scibasic.param.ovscignore = 3 muse_scibasic.param.crop = True muse_scibasic.param.cr = "none" muse_scibasic.param.xbox = 15 muse_scibasic.param.ybox = 40 muse_scibasic.param.passes = 2 muse_scibasic.param.thres = 5.8 muse_scibasic.param.combine = "none" muse_scibasic.param.nlow = 1 muse_scibasic.param.nhigh = 1 muse_scibasic.param.nkeep = 1 muse_scibasic.param.lsigma = 3.0 muse_scibasic.param.hsigma = 3.0 muse_scibasic.param.scale = True muse_scibasic.param.saveimage = True muse_scibasic.param.skylines = "5577.339,6300.304" muse_scibasic.param.skyhalfwidth = 5.0 muse_scibasic.param.skybinsize = 0.1 muse_scibasic.param.skyreject = "15.,15.,1" muse_scibasic.param.resample = False muse_scibasic.param.dlambda = 1.25 muse_scibasic.param.merge = False You may also set or overwrite some or all parameters by the recipe parameter `param`, as shown in the following example: :: import cpl muse_scibasic = cpl.Recipe("muse_scibasic") [...] res = muse_scibasic( ..., param = {"nifu":0, "overscan":"vpoly"}) .. seealso:: `cpl.Recipe `_ for more information about the recipe object. Bug reports ----------- Please report any problems to `Peter Weilbacher `_. Alternatively, you may send a report to the `ESO User Support Department `_. Copyright --------- This file is part of the MUSE Instrument Pipeline Copyright (C) 2005, 2019 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:: Peter Weilbacher