Sector 14



× Sector 14 was reprocessed in September 2020, updating timestamps, photometric apertures, data anomaly flags, and threshold crossing events. For more deatil please see the Reprocessing Information table below.
× Warning for Sector 14: Sector 14 is the first northern ecliptic hemisphere pointing. It uses an updated SPOC pipeline and makes use of CCD-specific anomaly flags. This sector uses TIC 8, which is based on Gaia DR2 astrometry and photometry, and uses Gaia DR2 parallaxes to inform stellar parameters.

Sector 14 Information

For full data release notes see: DRN19, DRN30 (reprocessing). For a list of TIC IDs with noted issues, see this list.

Updates:

  • Sector 14 is the first northern ecliptic hemisphere pointing.
  • This is first sector to make use of TIC 8, which is based on Gaia DR2 astrometry and photometry, and uses Gaia DR2 parallaxes to inform stellar parameters details are provided by Stassun et al (2019) and the TIC release notes.
  • The spacecraft is pointed to a higher ecliptic latitude (+85 degrees rather than +54 degrees) to mitigate issues with scattered light in Camera 1 and Camera 2.
  • Sector 14 processing is the first to make use of an updated SPOC data processing pipeline, SPOC Release 4.0
  • It is the first to make use of CCD-specific Data Anomaly Flags that mark cadences excluded due to high levels of scattered light. The flags are referred to as “Scattered Light” flags and marked with bit 13, value 4096 - see section 2 of the DRN.
  • The algorithm in the TPS module for searching for transiting planets was changed. An initial run of TPS is now used to identify problematic epochs that are assigned ”deemphasis weights” in the final run of TPS.

    • Sector Summary

  • Sector dates: July 18 to August 14 2019
  • Pointing: Northern hemispher
  • Days of Science Data Collection: 25.91
  • Days of Paused Data Collection: 0.95



    • Spacecraft Pointing (deg)

    RA dec roll
    Spacecraft 276.72 62.48 32.23
    Camera 1 297.76 29.19 106.4
    Camera 2 287.05 51.83 113.5
    Camera 3 256.18 71.57 321.23
    Camera 4 174.64 71.3 39.75



    Orbit Summary

    Orbits Dates (UTC)

    Start - End

    		 Cadence #

    Start - End

    		 Momentum dumps
    35 2019-07-18 - 2019-07-31 328243 - 337632 Every 4.4 days
    36 2019-08-01 - 2019-08-14 338316 - 347579 Every 4.4 days



    Sector Notes

    Noted Issue Description
    Spacecraft pointing This is the first sector of the northern ecliptic hemisphere survey. For northern pointings, scattered light from the Earth and Moon is a more persistent issue for Camera 1 and Camera 2 than for southern pointings. For this reason, the spacecraft pointing was set at +85 degrees in ecliptic latitude, so that Camera 2 and Camera 3 straddle the ecliptic pole

    Camera 1 still suffers from strong scattered light signals, and so guiding was disabled in Camera 1 for both orbits 35 and 36. Camera 4 alone was used for guiding in all of orbits 35 and 36.
    Scattered light In Sector 14, the Earth is above the sunshade for almost the entire sector, and the backgrounds are somewhat higher for longer periods of time than in other sectors. The 24 hour rotation period of the Earth and several harmonics thereof are also visible as oscillations in the background for most of both orbits. Finally, the Earth passes close to Camera 1 towards the last quarter of each orbit and saturates the detectors—these times were excluded with CCD-specific “Scattered Light” flags.

    Reprocessing Information: DRN30

    The data products of sectors 14 to 19 were generated using version 4.0 of the science processing pipeline and conform to the final set of data anomaly flags. A detailed description of the changes in the data products can be found in DRN30, but a summary is provided here.

    Update Description
    Timestamps: For 2 minute cadence and FFI data the timestamps were made more accurate. The differences between reprocessed data and previous data releases are less than 2.0 seconds in all cases.
    Photometric apertures: The apertures were increased in size for targets with Tmag less than 11.
    Data Anomaly Flags: Three new flags were added to mitigate the effects of scattered light;

    - Cadences with strong scattered light signals or saturation effects that corrupt the calibration data are flagged and removed from analysis.

    - Scattered light data anomaly flags are customized for each target, and flagged automatically based on the local background level.

    - Cadences with insufficient targets to derive cotrending basis vectors are flagged and the PDCSAP FLUX light curves are set to NULL at these times

    The modifications to the data anomaly flags also changed the cotrended light curves produced by PDC. The changes also result in new cotrending basis vectors for each CCD in each sector. The scattered light flags are now only applied to the PDCSAP FLUX light curves.
    Threshold Corssing Event issue: The planet search of the reprocessed light curves produced a different set of TCEs from the original processed data. Although there is a high degree of overlap between the original and reprocessed data (∼83% of targets produced TCEs in common), new TCEs were produced and not every TCE from previous data releases was recovered.