A Gaia motion correction reduces the difference between two public HD 20794 velocity tables on 64 nights in 2019–2023
Two public ESPRESSO radial velocity tables for HD 20794 have a large relative trend. We match 651 observations at identical stored times on 64 nights from August 2019 to March 2023 in CDS catalogue J/A+A/693/A297. The night mean difference has a fitted slope of 1.329 m/s per year. Independent Gaia DR3 astrometry gives a perspective acceleration of 1.352 m/s per year. Subtraction of this fixed slope reduces the centered night difference from 1.396 to 0.164 m/s RMS. When each season is omitted and the constant offset is fitted on other seasons, the error falls from 1.788 to 0.196 m/s. Alternative averages and time splits support the reduction. A separate 2018 sample covers only five nights over 50 days and does not support the same result. The correction also changes a conditional comparison of circular and eccentric planet models. The package preserves source tables, hashes, matched rows, a proposed correction table, code, all predictions, figures, and independent numerical checks. The result is consistent with different treatment of perspective acceleration in the two products. It does not establish their processing history, a new stellar acceleration, or a new planet. The audit was selected after an initial planet-model test exposed a data discrepancy. The corrected residuals have seasonal structure. Their RMS is a measure of table agreement, not an instrument noise floor.
HD 20794 · ESPRESSO · radial velocity · perspective acceleration · public data audit · Gaia DR3 · reproducibility · planet models
References
5- usesdoi:10.1051/0004-6361/202451769
We use the public HARPS and ESPRESSO tables in CDS catalogue J/A+A/693/A297. We use the published periods to define a conditional model benchmark.
- usesdoi:10.1051/0004-6361/202243940
We use Gaia DR3 astrometry for source 4847957293278177024 to calculate the perspective acceleration.
- usesdoi:10.1051/0004-6361/202039709
This paper describes the astrometric solution used in the Gaia calculation.
- doi:10.1051/0004-6361/202142262
This paper describes the sBART method used to produce one source table.
- doi:10.1051/0004-6361/202553869
This paper describes an ESPRESSO workflow that includes secular acceleration correction. We use it as context for the table audit.
Cited by
5 publicationsPublic catalog entries on Sciscape.
- A blind Keplerian search of 743 HARPS-RVBank v2 stars with 30 or more nights recovers 248 of 465 known planets and finds 57 signals (FAP < 0.1 %) with no known match that pass activity tests
Our blind search of HD 20794 finds the 18.32-day and 89.68-day planets, and our act test flags the 89.68-day signal. It does not detect the 147.0-day or the 647.6-day signals.
- usesAt fixed periods, HD 20794 circular-pair trials give tail rates of 0.9% for white noise and 17.9% for 30-day noise
We use its Gaia-based numerical perspective correction for the public ESPRESSO sBART velocities.
- usesAn HD 20794 design predicts 2.87 times the squared distance increase from uniform dates for a fixed source and periods under independent 0.5 m/s noise
We use its proposed perspective acceleration correction for the public sBART velocities.
- usesA 647.6-day eccentric curve fits 811 HD 20794 nights better than a fixed 2:1 circular pair under a 1 m/s noise term
We use its fixed Gaia motion correction for the sBART table and its source-table conventions. Our comparison adds two circular components in a fixed 2:1 period ratio and a direct measure of the information that separates the fitted means.
- usesAdding a 647.6-day signal to HARPS fits raises error on 65 corrected ESPRESSO nights for HD 20794 at fixed periods
We use its Gaia motion correction and adapt its MIT Kepler fitting code. We check the source hashes and add a complete HARPS-to-ESPRESSO test.