As data is reprocessed, so will the CBVs. Be sure to use CBVs with the same Data Release number as your data. Below is the current list of available Cotrending Basis Vector (CBV) files. These data products can be used to remove instrumental systematics from the K2 light curves. There is one FITS file per campaign. Each file contains 84 extensions, one for each CCD channel, and 16 basis vectors per channel. These basis vectors can be fit to the K2 SAP flux vector and the best fit vectors subtracted to significantly reduce systematic trends in the time series.

To download a particular file, click on the appropriate File Name below. Alternatively, ftp to archive.stsci.edu and cd to /missions/k2/cbv/ to see and/or download the complete list. Clicking on the linked data release numbers will display the corresponding data release notes (if available).

See the Kepler Archive Manual for a description of the CBV file format, and see Chapter 7 of the Data Characteristics Handbook for more information on the CBV characteristics and how to use them.

For a tool to fit and apply CBVs to your K2 light curve, see the kepcotrend task available with the PyKe software package