New community-prepared K2 light curves available at MAST

News article posted on by Ann Marie Cody

The project encourages members of our community to share and archive value-added data products derived from Kepler or K2 observations via the High Level Science Products (HLSP) service offered by the data archive at MAST.

In recent months, four bespoke data products have been released or updated in this way:

  • As of this month, the second version of the K2 Systematics Correction (K2SC) light curves prepared by Aigrain et al. has been made available. The K2SC pipeline aims to preserve astrophysical signals by modeling both spacecraft systematics and stellar variability at the same time. Version 2.0 incorporates Campaigns 7, 8, and 10 for the first time, includes a re-processing of Campaigns 3-6, and fixes the "cadence" and "quality" columns which were affected by a glitch in version 1.0.

  • As of July, the K2 Self-Flat-Fielding (K2SFF) light curves prepared by Vanderburg & Johnson have been updated. The K2SFF algorithm correlates flux measurements with the spacecraft's pointing to remove the motion-induced systematics. The latest update adds Campaign 11 light curves to the existing set which already included Campaigns 0 through 10.

  • As of March, the Planet candidates from OptimaL Aperture Reduction (POLAR) light curves and planet candidates prepared by Barros et al. have been made available for Campaigns 1 through 6. POLAR is a new product optimized for bright stars which are suitable for spectroscopic follow-up.

  • As of February, version 2.0 of the EPIC Variability Extraction and Removal for Exoplanet Science Targets (EVEREST) light curves was released. The update, detailed in Luger et al. (2017), provides light curves for Campaigns 0 through 8, and includes short cadence and saturated targets for the first time. EVEREST uses a pixel-level detrending model which is asserted to offer a photometric performance similar to that of Kepler's main mission for stars down to Kp=14.

More details on each of these data products, including a more detailed description and a list of references, is available via the K2 High Level Science Product page at MAST.

Additional teams are encouraged to make their bespoke data products available in the same way. In particular, PI's of large programs funded via the K2 Guest Observer Program are reminded of the requirement to develop and disseminate a value-added community resource product at the end of their performance period.

The project's helpdesk is available to help guide the delivery of new data products and connect authors with the archives.