Fits to twelve TESS sectors give weak evidence for wider Kepler-13 Ab transits from 2019 to 2024
We test whether later TESS data retain the known increase in the transit width of Kepler-13 Ab. We use twelve public SPOC light curves with 120 s samples from 2019 to 2024. Fixed coverage rules select 150 of 180 predicted transits. We fit a common spline profile with a free center, depth, and time scale for each transit. The measured width is the full width at half depth. It is not a physical contact duration. The primary PDC fit gives a width slope of 0.323 minutes per year. Its 95% interval is 0.023 to 0.614 minutes per year when we resample whole events within each sector and hold the common profile fixed. The SAP flux fit gives 0.179 minutes per year, with an interval of -0.132 to 0.487. Separate sector profiles give 0.252 minutes per year, with an interval of -0.061 to 0.536. Detector offsets and observing-year means also give intervals that include zero. The data permit a slow width increase, but the evidence depends on the model and error assumptions. A physical precession rate requires a model of the rotating star. We preserve the source files, their hashes, event and sector tables, source code, figures, and instructions for a new run.
Kepler-13 Ab · TESS · transit width · transit duration variation · orbital precession · public data · reproducible photometry
References
6- doi:10.1093/mnrasl/slz177
This study tests later TESS data for the direction of the width change reported with Kepler and 2019 TESS data.
- usesdoi:10.1093/mnras/stab701
Table 2 supplies the ephemeris that defines approximate event windows. Every selected event has a free fitted center.
- usesdoi:10.17909/t9-nmc8-f686
TESS 2-minute light curves for TIC 158324245, sectors 14, 15, 26, 40, 41, 53, 54, 55, 74, 75, 80, and 82. Exact product versions and hashes are in the supporting ZIP.
- doi:10.1093/mnras/staf334
Related work joins Kepler and K2 transit times with TESS data. This publication measures transit width.
- usesdoi:10.1117/1.JATIS.1.1.014003
The TESS mission supplies the public photometry used here.
- usesdoi:10.1117/12.2233418
The SPOC pipeline supplies the SAP and PDC light curves used here.
Cited by
8 publicationsPublic catalog entries on Sciscape.
- A shared circular model gives longer TOI-1518 b transits in late 2024 than in 2022
Related SCI work measures Kepler-13 Ab transit widths with event resampling and data controls. Our target, model, and code differ.
- usesTests of three fixed Kepler-13A periods in twelve TESS sectors depend on flux and noise assumptions
We reuse and check the twelve original TESS FITS files and their source provenance. Our analysis tests light signals outside eclipse at three fixed periods. The source publication measured transit width.
- usesFive TESS sectors give no clear linear increase in KELT-21 b transit width from 2021 to 2024
Its empirical width workflow and error controls helped define this test. We use new code and separate source data.
- A fixed Q2 profile reduced timing scatter across 30 averaging origins in 385 Kepler-13 b transits from Q7 to Q17
Related SCI work studies transit width in later TESS data for the same target.
- Local fits to six TESS sectors show smaller KELT-9 b transit widths from 2019 to 2024
This related empirical width study gives context for sensitivity to transit profile and detector choices.
- usesA fixed profile test gives a Kepler-13 Ab asymmetry slope interval that includes zero for 2019–2024
Verified source of original FITS files, fixed event selection, fixed empirical reference profiles, and reused normalization and spline code.
- Local fits to two-minute TESS light curves show wider TOI-1518 b transits in 2024 than in 2022
This related study measures TESS transit widths for Kepler-13 Ab and resamples whole events. The present study uses a different target and separate local profile fits. No code is reused.
- usesLocal TESS eclipse fits give a Kepler-13 Ab depth slope interval that includes zero for 2019–2024
We reuse its verified original FITS files, raw source hashes, sector metadata, and transit-depth fits for a new secondary eclipse test.