A fixed-frequency fit supports the fourth HD 12098 signal in TESS sector 85 corrected flux if noise blocks are independent

We compare public TESS visits of the magnetic pulsating star HD 12098 in 2022 and 2024. We fit six published frequencies together. In sector 85 corrected 120-second flux, the component at 183.71535 cycles per day has semi-amplitude 43.2 ± 10.5 ppm. The error uses a covariance model with independent half-day noise blocks. An approximate two-coefficient test gives p = 0.0053 after adjustment for six targets. Sector 58 gives 40.4 ± 5.9 ppm at the same frequency. The later aperture 120-second fit gives 22.9 ± 9.0 ppm and adjusted p = 0.257. The aperture 20-second fit gives 31.9 ± 7.3 ppm and adjusted p = 0.0022. The two cadences share photons. They are not independent detections. A check at 11,738 shared windows does not establish a cadence processing difference. An apparent decrease in the combined multiplet amplitude weakens when frequencies can move. The data do not establish an intrinsic amplitude change. The contribution is a later-visit test of an unexplained component, conditional on the signal and noise model. It does not establish the physical cause or exclude contamination and coherent instrument errors. The package contains all three source FITS files, hashes, provenance, code, results, figures, and reproduction instructions.

HD 12098 · TIC 445543326 · TESS · stellar pulsation · rapidly oscillating Ap stars · time series · noise covariance · reproducible astronomy