Introduction

pySYD was initially established as a one-to-one translation of the IDL-based SYD pipeline from Huber et al. (2009). In the Kepler days, SYD was extensively used to measure global asteroseismic parameters for many stars (e.g., [H2011]; [C2014]; [S2017a]; [Y2018]).

In order to process and analyze the enormous amounts of data from Kepler in real time, there were a a handful of other closed-source pipelines developed around the same time that perform roughly similar types of analyses. In fact, there were several papers that compared results from each of these pipelines in order to ensure the reproducibility of science results from the Kepler legacy sample ([L2017]; [S2017b]).

pySYD adapts the well-tested methodology from SYD while simultaneously improving these existing analyses and expanding upon numerous new features. Some improvements include:

  • automated background model comparison and selection

  • parallel processing and other easy compatabilities for running many stars

  • easily customizable with command-line friendly interface

  • modular and adaptable across different applications

  • saves reproducible samples for future analyses (i.e. seeds)


Benchmarking to the Kepler legacy sample

We ran pySYD on ~100 Kepler legacy stars (defined here) observed in short-cadence and compared the output to SYD results from [S2017a]. The same time series and power spectra were used for both analyses, which are publicly available and hosted online c/o KASOC 1. The resulting values are compared for the two methods below for numax (\(\rm \nu_{max}\), left) and dnu (\(\Delta\nu\), right).

Comparison of the `pySYD` and `SYD` pipelines

The residuals show no strong systematics to within <0.5% in Dnu and <~1% in numax, which is smaller than the typical random uncertainties. This confirms that the open-source Python package pySYD provides consistent results with the legacy IDL version that has been used extensively in the literature.



References

1

Kepler Asteroseismic Science Operations Center

C2014

Chaplin et al., 2014

H2011

Huber et al., 2011

L2017

Lund et al., 2017

S2017a(1,2)

Serenelli et al., 2017

S2017b

Silva Aguirre et al., 2017

Y2018

Yu et al., 2018