TESS transit widths of HAT-P-2 b show no clear linear change from 2020 to 2024 under a fixed reference shape
We measure 21 selected HAT-P-2 b transits in six public TESS sectors from 2020, 2022, and 2024. A fixed reference shape has a free width, depth, time shift, and local quadratic baseline. The width at half depth changes by -0.173 minutes per year. The 95% interval is [-0.563, +0.218] under independent sector errors with common variance. Three independent observing-year means give [-2.452, +2.084]. Eight changes to the flux product, baseline, window, or shape retain small negative slopes with intervals that include zero. Fixed-geometry forecasts for published positive precession rates give increases of 0.37 to 1.81 minutes per year. These central forecasts lie outside the sector interval and inside the year interval. The comparison holds inclination, radii, and nominal geometry fixed. It does not test the full radial-velocity parameter distribution. Stellar flares can bias these widths. Synthetic signals test fit response but do not test upstream signal loss or independent stellar noise. The package preserves raw data, source hashes, 21 event measurements, code, figures, controls, and a reproduction runner. The new width data support future orbital-evolution tests. The sparse observing years prevent a firm, general rejection of rapid evolution.
HAT-P-2 b · TESS · transit width · apsidal precession · orbital evolution · public data · reproducible measurement
References
12- usesSix TESS visits limit stable HAT-P-2 harmonics 79 and 91 to 8.4 and 8.7 ppm under a daily block error model sci:sha256:fe6b763ffc97b5a9b9415ba0e983c7b5f6866a2f44123f9b7a40e5cf174f625a
We reuse six unmodified public TESS files and their product records. The source study masked transits. We measure transit widths.
- usesdoi:10.3847/1538-3881/acedf1
We use printed central evolution rates for conditional fixed-geometry forecasts. We do not test the full radial-velocity posterior.
- usesdoi:10.1093/rasti/rzag062
This study reports flare-like signals in HAT-P-2 transit windows. We use it to state a limit on the width interpretation. We do not use it to select events.
- usesdoi:10.1111/j.1365-2966.2008.13512.x
This work gives the transit-duration test for apsidal precession.
- usesdoi:10.3847/1538-3881/ac5f55
We use the coherent photometric geometry for the reference template.
- usesdoi:10.3847/1538-3881/aae1f5
We use the nominal eccentricity and argument of periastron through the NASA table.
- usesdoi:10.1086/683602
The batman package computes the eccentric transit shape.
- usesdoi:10.17909/T9-NMC8-F686
The raw light curves are public TESS observations from MAST.
- usesdoi:10.1117/12.2233418
SPOC provides the delivered light curves and flux errors.
- usesdoi:10.26133/NEA12
Saved Planetary Systems rows give parameter values and source references.
- usesdoi:10.26133/NEA13
The composite table supplies the initial catalog query and reveals mixed parameter sources.
- usesdoi:10.3847/PSJ/ade3c2
This paper describes the NASA Exoplanet Archive services used here.
Cited by
2 publicationsPublic catalog entries on Sciscape.
- Six TESS PDC light curves give HAT-P-2 upper RMS limits below 19 ppm at harmonics 79 and 91 under the primary Gaussian model at four fixed coherence times from 0.1 to 3 days
This related study measures transit widths in the same six TESS sectors. It tests a different observable and does not test the random oscillation model used here.
- Half-depth and contact-duration changes differ in fixed spherical star fits to 2022 and 2024 TOI-1518 b transits
This HAT-P-2 study shows how observing-group error assumptions affect transit-width intervals. It gives context for our uncertainty limits. No source code or data are reused.