KBONUS-BKG

KBONUS-BKG uses the Linearized Field Deblending (LFD) method, a Point Spread Function (PSF) photometry algorithm, to create PSF light curves. Gaia DR3 data is used as an input catalog to extract 606,900 light curves, from which 406,548 correspond to background sources and 200,352 are Kepler targets. PSF models were fitted using Kepler's full-frame images and later evaluated in the Target Pixel Files (TPFs) of Kepler targets. The LFD method provides a mean PSF estimate and a perturbed PSF that corrects for systematics within an observing quarter. Additionally, aperture photometry is estimated directly from the PSF shape per source and optimized for flux completeness and contamination. The PSF light curves have comparable quality as those computed by the Kepler pipeline, with combined differential photometric precision (CDPP) values under 100 ppm for sources brighter than G = 16. The light curve files include PSF, aperture photometry, and relevant extraction metrics. A full description of this dataset can be found in Martinez-Palomera et al. (2023) and the Python library PSFMachine that was used to extract the light curves for this data set.  See Jupyter Notebook tutorials on how to load the light curves and what to expect in the FITS files.

Lightcurves are available in the MAST Portal (web-based, cross-mission search interface) and Astroquery (Python package to search for and download files from Python scripts you write). We also provide a bulk download cURL script for all lightcurves below. Catalogs and bundled lightcurves for specific targets can be accessed via the direct download table below.

Portal Advanced Search:

Set the Provenance Name filter to KBONUS-BKG and the target names or the RA/Dec filters to the interested field of view in the Portal Advanced Search to find individual lightcurves. Each observation in the Portal contains a single source's lightcurve. Note that since the total number of KBONUS-BKG is larger than the load limit (50,000) and the download limit (500,000), you can use the direct download bulk script below to download all lightcurves or narrow down your search for specific lightcurves using the RA/Dec filters.

Astroquery Access:

The lightcurves can also be retrieved programmatically by using the astroquery—mast module. See the code example below for counting the total number of observations and retrieving and downloading lightcurve files.  See more examples in Astroquery and API filter parameters.

from astroquery.mast import Observations

# Getting the total observation counts
print(Observations.query_criteria_count(provenance_name= "kbonus-bkg"))

# Filtering observations by Gaia DR3 target names and RA/Dec
gaia_obs = Observations.query_criteria(provenance_name= "kbonus-bkg", target_name ="*GAIA DR3*", s_ra=[293.2, 294.5], s_dec=[50.5, 51.5])

# Getting the product list
data_products = Observations.get_product_list(gaia_obs)
print(data_products)

# Download the observations
Observations.download_products(data_products)

• MAST Portal

  

  A web-based interface for cross-mission searches of data at MAST or the Virtual Observatory

  Portal

• MAST Astroquery

  

  Search for and retrieve KBONUS-BKG data products programmatically.

  MAST Astroquery

The catalog released with this work contains the list of extracted sources resulting in a light curve FITS file. It also contains extraction metrics and availability flags that can be used to filter sources. The catalogs can be accessed via direct links below.

To facilitate data access to specific source types, the team has created the following data bundles: