specex.zeropoints module
SPECEX - SPECtra EXtractor.
This module provides functions to calculate the zeropoints of a FITS image.
For more information take a look at the following links:
Copyright (C) 2022-2023 Maurizio D’Addona <mauritiusdadd@gmail.com>
- specex.zeropoints.get_zeropoint_info(filename, ext=0)[source]
Compute zero-point information from a fits image.
For more information about zeropoints take a look at the following links: https://www.stsci.edu/hst/wfpc2/Wfpc2_dhb/wfpc2_ch52.html https://www.stsci.edu/hst/instrumentation/acs/data-analysis/zeropoints
Parameters
- filenamestr
The path of the fits file image.
- extint, optional
The FITS extension containing the image data. The default value is 0.
Returns
- zpt_dictditct
A dicttionary containing the zero-point information. The dictionary contains the following items:
- exp_timefloat
The exposure time
- phot_f_lamfloat
The value of PHOTFLAM. This is the flux of a source with constant flux per unit wavelength (in erg s-1 cm-2 A-1) which produces a count rate of 1 count per second.
- phot_p_lamfloat
the pivot wavelength (in Angstrom)
- zero_pointsloat
the zero point value
- zero_point_pfloat
the zero point value plus 2.5 times log10 of the exposure time
- zero_point_mfloat
the zero point value minus 2.5 times log10 of the exposure time
- counts_to_fluxfloat
Quantity to convert counts to flux units