abigailStev / cross_correlation

Computing the energy-dependent cross-correlation function of X-ray light curves to do phase-resolved spectroscopy of quasi-periodic oscillations (QPOs).

cross_correlation

Computes the cross-correlation function of a broad reference energy band with narrow energy channels of interest. Please see Stevens & Uttley 2016 for reference.

The functionality of this software will be folded into Stingray, so please get involved there.

Contents

ccf.py

Computes the cross-correlation function of a broad reference energy band with narrow energy channels of interest (detector energy channels) to do phase-resolved spectroscopy. Requires a FITS-format event list or light curve, or list of FITS-format event lists or light curves, as input (as created in rxte_reduce/good_events.sh). Able to accept a separate file for the reference band, for a multi-wavelength light curve. Requires whizzy_scripts/tools.py.

bootstrap_ccf.py

Like ccf.py, but to be used for bootstrapping the data, where it selects a certain subset (with replacement) of the segments and goes on from there. To be used in run_bootstrap_ccf.sh.

loop_ccf.sh

Bash script to compute the ccf of individual observations and stitch the plots together in a gif! Requires ImageMagick to be installed, so that a gif can be created at the command line.

plot_2d.py

Plots the two-dimensional cross correlation function.

plot_ccf.py

Plots the cross-correlation function in one dimension (i.e. for one energy channel).

plot_cs.py

Plots the cross spectrum. Only intended for testing purposes.

plot_multi.py

Plots multiple 1-D cross-correlation functions from different energy channels on one plot.

run_ccf.sh

Bash script to run ccf.py and plotting scripts.

run_bootstrap_ccf.sh

Bash script to run bootstrap_ccf.py.

ccf_OIR.py, run_ccf_OIR.py

These are offshoots of their non-_OIR counterparts, created for collaboration with Federico Vincentelli and Piergiorgio Casella. TODO: incorporate these in the regular ccf.py and run_ccf.py.

Authors

• Abigail Stevens (UvA API)

Collaborators

• Phil Uttley (UvA API) -- Math and stats theory
• Federico Vincentelli (INAF Roma, INAF Brera) -- Adding option for IR and/or optical reference band

Copyright

All content © 2014-2017 the Authors, and is distributed under the MIT Licence. See LICENSE.md for details.

If you use this code, please cite Stevens & Uttley 2016.

The functionality of this software will be folded into Stingray, so please get involved there.