The fors_extract_slits recipe

fors_extract_slits

Synopsis

Spatial rectification of spectral image

Description

This recipe is used to extract MOS/MXU slit spectra, following their curvature, and to remap them into a spatially rectified image.

Please refer to the FORS Pipeline User’s Manual for details about the spectra remapping technique. Note however that the interpolation is done exclusively along the spatial direction, and therefore the output rectified image will have the same x size of the input spectral image.

In the table below the MXU acronym can be alternatively read as MOS.

Input files

DO category:               Type:       Explanation:         Required:
LAMP_UNBIAS_MXU
or SCIENCE_UNBIAS_MXU
or SCIENCE_UNFLAT_MXU
or STANDARD_UNBIAS_MXU
or STANDARD_UNFLAT_MXU
or UNMAPPED_SCI_MXU
or UNMAPPED_STD_MXU
or UNMAPPED_SKY_SCI_MXU
or UNMAPPED_SKY_STD_MXU    Calib       Spectral frame          Y
SLIT_LOCATION_DETECT_MXU
or SLIT_LOCATION_MXU       Calib       Master flat frame       Y
CURV_COEFF_MXU             Calib       Spectral curvature      Y
GRISM_TABLE                Calib       Grism table             .

Output files

DO category:               Data type:  Explanation:
RECTIFIED_LAMP_MXU
or RECTIFIED_ALL_SCI_MXU
or RECTIFIED_ALL_STD_MXU
or RECTIFIED_SCI_MXU
or RECTIFIED_STD_MXU
or RECTIFIED_SKY_SCI_MXU
or RECTIFIED_SKY_STD_MXU   FITS image  Rectified slit spectra

Constructor

cpl.Recipe("fors_extract_slits")

Create an object for the recipe fors_extract_slits.

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

Parameters

fors_extract_slits.param.dispersion

Expected spectral dispersion (Angstrom/pixel) (float; default: 0.0) [default=0.0].

fors_extract_slits.param.startwavelength

Start wavelength in spectral extraction (float; default: 0.0) [default=0.0].

fors_extract_slits.param.endwavelength

End wavelength in spectral extraction (float; default: 0.0) [default=0.0].

fors_extract_slits.param.flux

Apply flux conservation (bool; default: True) [default=True].

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

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

fors_extract_slits.param.dispersion = 0.0
fors_extract_slits.param.startwavelength = 0.0
fors_extract_slits.param.endwavelength = 0.0
fors_extract_slits.param.flux = True

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

import cpl
fors_extract_slits = cpl.Recipe("fors_extract_slits")
[...]
res = fors_extract_slits( ..., param = {"dispersion":0.0, "startwavelength":0.0})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

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