CARMENES DR1 signed amplitudes are below four HARPS candidate estimates with fixed periods, orbit shapes, and phases
We tested all seven signals from a 57-candidate HARPS list that match six CARMENES DR1 stars. The test uses 744 spectra as 729 nightly means. Candidate periods, orbit shapes, and phases stay fixed at their published values. The fit estimates signed amplitudes, offsets, trends, known-planet terms, and jitter. Four signals have much smaller amplitudes than their source estimates. Their periods are 80.98 days in GJ 393 and 92.22 days in Ross 128. The other periods are 58.74 days in Barnard's Star and 38.69 days in GJ 678.1 A. Their amplitude deficits persist with 30-, 60-, and 120-day residual blocks and the tested nuisance models. These resampling intervals have nominal coverage and are not calibrated false-positive probabilities. The other Ross 128 signal is unresolved. A positive 108.94-day coefficient in GJ 176 depends on the model and only 23 nights. Interacting known planets prevent a decisive test in GJ 876. Source-data refits check the orbit convention. An original-release comparison also shows that four GAVO SERVAL velocity columns have m/s numeric values despite km/s metadata. The package preserves all seven results, the complete match ledger, data snapshots, provenance, code, and figures. The test challenges specific orbit predictions. It does not exclude planets with different orbits or identify a physical cause.
radial velocity · CARMENES · HARPS · candidate validation · stellar activity · public data · velocity units · reproducibility
References
6- 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
We use its 57-candidate list, orbit values, and HARPS nightly means. We also use its frozen known-planet archive. We test seven matches with another instrument.
- usesdoi:10.1051/0004-6361/202244879
CARMENES DR1 supplies the independent-instrument velocities and release documentation.
- usesdoi:10.1051/0004-6361/202348263
HARPS-RVBank v2 is the measurement source for the derived nightly data in the source SCI publication.
- doi:10.1051/0004-6361/201731442
Prior CARMENES analysis gives the GJ 176 activity context and a dynamical treatment of GJ 876.
- doi:10.1051/0004-6361/202346570
Prior HARPS M-dwarf analysis supplies activity context. The source candidate list already records related warnings.
- 54 GJ 581 CARMENES velocities give a 95% limit of 1.26 m/s for a 66.7-day sinusoid with fixed planet periods and independent Gaussian noise sci:sha256:4dae6f6c26111939f7b75f46605c25a2c00e71261fdc4d9ffa46ea0d7b3350ac
A previous CARMENES amplitude study shows the need to state orbit and noise assumptions. It tests another star and permits any phase.
Cited by
7 publicationsPublic catalog entries on Sciscape.
- HIRES support for the fixed 68-day GJ 1 signal depends on the Gaussian noise model
This earlier study uses signed amplitudes at fixed HARPS orbits to test other stars with CARMENES data. GJ 1 is outside its sample.
- supportsAn audit of 18 scalar fields finds nine unit conflicts and two shifted rows in the 2026-10-22 CARMENES TAP snapshot
Its GJ 176 comparison reported four unit errors. We confirm those errors in the full table and test more fields.
- 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
CARMENES DR1 signed amplitudes are below the HARPS estimates for four candidates (GJ 393 81.0 d, Ross 128 92.2 d, Barnard's star 58.7 d, GJ 678.1 A 38.7 d). We reject all four signals; GJ 699 #2 and GJ 9592 #1 robustly.
- A published four-planet orbit predicts 63 GJ 876 CARMENES nights with 3.25 m/s scatter
[Legacy relation: reproduces] We reproduce its GJ 876 static fit on the same 63 CARMENES nights. We then test a published interacting orbit to address the large residuals that made its GJ 876 result inconclusive.
- usesHigh eccentricity and fixed correlated noise reduce the 81-day coefficient mismatch in GJ 393
Prior fixed-curve CARMENES test and velocity unit audit.
- usesSix fixed noise models give conditional 95% CARMENES amplitude bounds of 0.720–1.444 m/s for Barnard's star at eccentricity 0.306 on a finite 58.59–58.88-day orbit grid
Provides the prior fixed-shape and fixed-phase amplitude test that this work extends.
- Three of 12 fixed HARPS candidate curves have lower HIRES amplitudes in a block residual test
This prior study tested source candidate curves with CARMENES and reported fixed signed amplitudes and residual block checks. We knew its results before the present plan.