Three fixed HARPS curves show no detected blue to red velocity difference in 25 ESPRESSO nights of HD 32564 under independent nightly errors
We test whether three proposed signals in HD 32564 have different velocity scales in the blue and red ESPRESSO detector groups. We use 25 public observations from 2023 to 2025 and keep the HARPS periods, phases, and curve shapes fixed. The periods are 2.5565847, 11.0624209, and 23.6066541 days. We extract velocities from 90 blue and 58 red spectral slices with fixed slice weights and shifted mean profiles. The signed red minus blue velocity coefficients are -0.019, -0.023, and +0.032 m/s. Their separate 95% intervals are [-0.748, +0.710], [-0.735, +0.689], and [-0.651, +0.714] m/s under independent Gaussian nightly errors with a common variance. The difference has 0.934 m/s scatter. The global three-curve test gives F(3,21)=0.0104 and a wild-bootstrap p value of 0.9977. All intervals include zero when we change the profile fit width, slice weights, group offsets, or five water-corrected products. Some controls widen interval endpoints to 1.20 m/s. We provide the band velocities, all 30 input CCF products, hashes, archive records, code, and figures. This is a new wavelength test on the same observations used by the earlier SCI study. It does not add independent observations or confirm planets. The bounds apply to projections onto the fixed source curves. They omit source phase uncertainty and unknown errors correlated in time.
HD 32564 · ESPRESSO · HARPS · radial velocity · chromatic velocity · cross-correlation function · exoplanet candidates · public archive · reproducible astronomy
References
5- usesThree frozen HARPS curves reduce HD 32564 velocity scatter from 4.33 to 2.77 m/s on 25 ESPRESSO nights sci:sha256:8d629ee537837cd7f7f4b3d9b0f34219daafeddd643fd324a7f50b410f7559cb
We use its 25-night ESPRESSO sample, 30 CCF products, source curve parameters, and archive records. We add separate blue and red velocities and a paired wavelength test.
- usesA 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 sci:sha256:17e2629023ac1bcbb507eb643afc93a73a34d8a9d1ba2357cc22bd7bc4f108cb
It supplied the original HARPS candidate curves. We use the first three fixed curves as copied in the later ESPRESSO study.
- doi:10.1051/0004-6361/202348263
- doi:10.1051/0004-6361/202038306
- doi:10.1051/0004-6361/202142353
Cited by
2 publicationsPublic catalog entries on Sciscape.
- supportsIndependent RVs reject 13 of 25 testable HARPS-RVBank v2 candidates (3 if HARPS errors double) and agree with a 19.7-day HD 111232 signal, with linear-trend nuisance models
Found no blue-to-red velocity difference for the 2.56-d, 11.06-d and 23.61-d HD 32564 curves in the same ESPRESSO nights. Our test adds the 49.21-d signal, the post-2022 HARPS nights and a test with the HARPS posterior.
- 2023 Barnard's Star date means give a positive 4.1244-day band term at the 2021–2022 phase under independent Gaussian errors
This study gives a paired band test for a different star with coefficients on fixed curves.