An extension to ceres.
This package was written as an extension to the CERES reduction pipeline (https://github.com/rabrahm/ceres) in the sense that it takes spectra reduced by it and extracts some activity indicators (CCF FWHM, BIS, CONTRAST) and calculates others (S index, Ha, HeI, NaID1D2)
It's been tested to work on FEROS and FIDEOS spectra. Feel free to use it with other instruments and let me know if it works :)
You can try running
pip install cerespp
If that fails you can clone the repository with
$ git clone https://github.com/jvines/Ceres-plusplus $ cd Ceres-plusplus $ python setup.py install
Ceres-plusplus depends on the following packages:
- numpy (https://numpy.org/)
- scipy (https://www.scipy.org/)
- matplotlib (for plotting, but it's optional for the core functionality) (https://matplotlib.org/)
- astropy (https://www.astropy.org/)
- PyAstronomy (https://pyastronomy.readthedocs.io/en/latest/)
- tqdm (https://tqdm.github.io/)
- termcolor (https://pypi.org/project/termcolor/)
Usage is simple, start by importing
cerespp, optionally you can use
fetch the files. After importing (and having ready your files) the
get_activities function, grab a coffee, and wait for your indicators!.
Below there's an example script
import cerespp import glob files = glob.glob('path/to/fits/files/*.fits') act, header = cerespp.get_activities(files, 'output/path/filename.dat')
files is a list with the fits files to process, the output
header are the activities and the header of the file (i.e. the names of the
cerespp automatically saves the output in a file in the desired
location, but if you need the output on the session you're working in
(in a jupyter notebook, for example), that's what
header are for ;)
cerespp offers some plotting tools to visually check things! The most
important ones are plots showing the activity lines and their surroundings.
Creating these is easy:
import cerespp import glob # These are the available lines. You can choose which ones to plot here lines = ['CaHK', 'Ha', 'HeI', 'NaID1D2'] files = glob.glob('path/to/fits/files/*.fits') # This function creates the plots from a fits file directly cerespp.line_plot_from_file(files, lines, 'output/path/', 'starname')
There's a notebook exemplifying the usage in the examples folder!
How it works
cerespp first calculates a radial velocity to correct the spectrum to
rest-frame, after this has been done it extracts the available data from the
fits headers (CCF FWHM, BIS, CONTRAST) and finally it merges the echelle orders
and computes the activity indicators!
The radial velocity is computed using the standard cross-correlation function
method, and thus you can specify which mask to use with the
mask keyword in
get_activities. Available masks are
G2, K0, K5, and
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.