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The sinfo_utl_skycor recipe

sinfo_utl_skycor

Synopsis

Sky lines residuals correction

Description

This recipe perform a correction of possible sky line residuals in the object cube after standard data reduction.

Input frames are cubes with target and sky observations.

Their tags can be respectively OBS_OBJ (or OBS_PSF or OBS_STD) and OBS_SKY.

The output is a cube with same tag as the corresponding input target frame.

Constructor

cpl.Recipe("sinfo_utl_skycor")

Create an object for the recipe sinfo_utl_skycor.

import cpl
sinfo_utl_skycor = cpl.Recipe("sinfo_utl_skycor")

Parameters

sinfo_utl_skycor.param.skycor_mask_ws

Starting wavelength for object-sky cross correlation (float; default: 1.4) [default=1.4].

sinfo_utl_skycor.param.skycor_mask_we

End wavelength for object-sky cross correlation (float; default: 2.5) [default=2.5].

sinfo_utl_skycor.param.skycor_min_frac

Threshold value for fraction of spatial pixels to be sky (float; default: 0.8) [default=0.8].

sinfo_utl_skycor.param.skycor_sky_bkg_filter_width

Width of sky-thermal background pre filter (to remove emission lines before fitting a Black Body). (long; default: 12) [default=12].

sinfo_utl_skycor.param.skycor_line_hw

Threshold value for full width in pixels of unresolved emission line. Lines with FWHM smaller than this value are not considered in the object-sky cross correlation and in computation of the optimal sky lines scaling factor (float; default: 4.0) [default=4.0].

sinfo_utl_skycor.param.skycor_scale_method

Optimal sky lines scaling factor computation method: amoeba fit (0), maximum likelihood (1) (long; default: 1) [default=1].

sinfo_utl_skycor.param.skycor_rot_cor

Computes scaling factor correction due to rotational levels transitions (bool; default: False) [default=False].

sinfo_utl_skycor.param.skycor_fit_obj_noise

Do Gaussian fit of object noise (bool; default: False) [default=False].

sinfo_utl_skycor.param.skycor_niter

Number of iterations of background fit (long; default: 10) [default=10].

sinfo_utl_skycor.param.skycor_pshift

Sky spectrum shift towar object (float; default: 0.0) [default=0.0].

sinfo_utl_skycor.param.skycor_llx

Lower left X defining object spectrum location (long; default: 1) [default=1].

sinfo_utl_skycor.param.skycor_lly

Lower left Y defining object spectrum location (long; default: 1) [default=1].

sinfo_utl_skycor.param.skycor_urx

Upper right X defining object spectrum location (long; default: 64) [default=64].

sinfo_utl_skycor.param.skycor_ury

Upper right Y defining object spectrum location (long; default: 64) [default=64].

sinfo_utl_skycor.param.skycor_sub_thr_bkg_from_obj

Subtract thermal background contribute from object spectra. Set it to TRUE if stack-sub_raw_sky is set to FALSE (bool; default: False) [default=False].

The following code snippet shows the default settings for the available parameters.

import cpl
sinfo_utl_skycor = cpl.Recipe("sinfo_utl_skycor")

sinfo_utl_skycor.param.skycor_mask_ws = 1.4
sinfo_utl_skycor.param.skycor_mask_we = 2.5
sinfo_utl_skycor.param.skycor_min_frac = 0.8
sinfo_utl_skycor.param.skycor_sky_bkg_filter_width = 12
sinfo_utl_skycor.param.skycor_line_hw = 4.0
sinfo_utl_skycor.param.skycor_scale_method = 1
sinfo_utl_skycor.param.skycor_rot_cor = False
sinfo_utl_skycor.param.skycor_fit_obj_noise = False
sinfo_utl_skycor.param.skycor_niter = 10
sinfo_utl_skycor.param.skycor_pshift = 0.0
sinfo_utl_skycor.param.skycor_llx = 1
sinfo_utl_skycor.param.skycor_lly = 1
sinfo_utl_skycor.param.skycor_urx = 64
sinfo_utl_skycor.param.skycor_ury = 64
sinfo_utl_skycor.param.skycor_sub_thr_bkg_from_obj = False

You may also set or overwrite some or all parameters by the recipe parameter param, as shown in the following example:

import cpl
sinfo_utl_skycor = cpl.Recipe("sinfo_utl_skycor")
[...]
res = sinfo_utl_skycor( ..., param = {"skycor_mask_ws":1.4, "skycor_mask_we":2.5})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

Please report any problems to Andrea Modigliani. Alternatively, you may send a report to the ESO User Support Department.