The fors_sumflux recipe

fors_sumflux

Synopsis

Integrate flux from all or part of the input frame

Description

This recipe is used to monitor any lamp flux on the CCD. The input raw image should be either a FLUX_ARC_LSS or a FLUX_FLAT_LSS frame. After the background subtraction the total signal is integrated and divided by the exposure time and by the total number of CCD original pixels (keeping into account a possible rebinned readout). In the case of FORS2 frames the background is the median level evaluated from the available overscan regions. In the case of FORS1 data, where overscan regions are missing, the background is evaluated as the median level of the first 200 CCD columns for flat field data, while for arc lamp data a background map evaluated from the regions without spectral lines is computed and subtracted. The background subtracted frame is written to output in all cases, and the QC parameters QC LAMP FLUX and QC LAMP FLUXERR are computed.

Input files

DO category:      Type:       Explanation:         Required:
FLUX_FLAT_LSS     Raw         Flat field exposure     Y
or FLUX_ARC_LSS   Raw         Arc lamp exposure       Y

Output files

DO category:      Data type:  Explanation:
FLUX_LAMP_LSS     FITS image  Background subtracted integration region

Constructor

cpl.Recipe("fors_sumflux")

Create an object for the recipe fors_sumflux.

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

Parameters

fors_sumflux.param.xlow

X coordinate of lower left corner of integration region (pixel) (int; default: 0) [default=0].

fors_sumflux.param.ylow

Y coordinate of lower left corner of integration region (pixel) (int; default: 0) [default=0].

fors_sumflux.param.xhigh

X coordinate of upper right corner of integration region (pixel) (0 = CCD size) (int; default: 0) [default=0].

fors_sumflux.param.yhigh

Y coordinate of upper right corner of integration region (pixel) (0 = CCD size) (int; default: 0) [default=0].

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

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

fors_sumflux.param.xlow = 0
fors_sumflux.param.ylow = 0
fors_sumflux.param.xhigh = 0
fors_sumflux.param.yhigh = 0

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

import cpl
fors_sumflux = cpl.Recipe("fors_sumflux")
[...]
res = fors_sumflux( ..., param = {"xlow":0, "ylow":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.