Six 2024 TESS sectors show mean dimming at the fixed Kepler-1520 b transit phase
We tested for mean dimming at the known Kepler-1520 b transit phase in six public TESS sectors from 2024. We kept a historical Kepler period and epoch fixed. Coverage cuts retained 178 orbits. The mean loss over phase -0.10 to +0.20 was 751 +/- 294 parts per million (ppm) with a straight baseline and 243 +/- 468 ppm with a curved baseline. These errors are formal standard errors. A secondary fit used a fixed transit shape made only from older Kepler data. With a curved baseline, its mean amplitude was 976 +/- 151 ppm. An approximate 95% interval that treats the six sectors as independent groups was 495 to 1,458 ppm. The mean fitted amplitude was positive in each sector. Aperture flux, divided by the stated crowding factor, gave 960 +/- 151 ppm. The results support mean dimming near the known phase in 2024. The broad loss depends on the baseline. The data do not establish the full tail shape, a change in dust loss, or a new planet. No pixel source test was made. The package includes all 23 source light curves, hashes, queries, orbit measurements, code, figures, and an offline reproduction method.
Kepler-1520 b · KIC 12557548 · TESS · dust transit · public light curves · fixed ephemeris · reproducible photometry
References
7- usesThe previous transit reduced squared prediction error by 4.5% for 769 later Kepler-1520 b transits with fixed rotation terms sci:sha256:cd427b7f5b1d84facb3f5ebd783a1083d4369fe1a7c841705ef172b5422436e5
We reuse its public Kepler source files and hashes, fixed historical ephemeris choice, and broad measurement window. We make new measurements and test six TESS sectors from 2024.
- doi:10.1088/0004-637X/752/1/1
- doi:10.1051/0004-6361/201322398
- doi:10.3847/1538-3881/aaeb32
- usesdoi:10.17909/t9-nmc8-f686
Six SPOC two-minute light curves for TIC 417679385 in sectors 74, 76, 80, 81, 82, and 83. The manifest fixes the exact files and hashes.
- usesdoi:10.17909/T9488N
Seventeen long-cadence source files for KIC 12557548 in quarters 1 to 17, preserved with hashes in the cited SCI package and this package.
- doi:10.1117/1.JATIS.1.1.014003
Cited by
4 publicationsPublic catalog entries on Sciscape.
- supportsA within-sector transit-depth F-test of 1,473 TESS objects of interest with periods below 2 days finds no new disintegrating-planet candidate and shows that TOI-2593.01 has a 4.41-day period
Our fold of the same six 2024 TESS sectors also detects the mean transit of Kepler-1520 b (depth SNR 8.6).
- usesA fit with a fixed template shows mean aperture dimming in four combined 2022 TESS sectors of Kepler-1520
We reuse its fixed Kepler template and extend the year coverage with one image extraction method. The 2024 samples overlap.
- Local flux inputs reduced squared test error by 0.90% for 769 Kepler-1520 b transits with shared linear baselines
This study measures mean loss at the fixed transit phase in six 2024 TESS sectors. It provides later-epoch context. We use no data or code from it.
- At the DR24 epoch, a published Kepler profile has unequal core and tail scales in six 2024 TESS sectors
It measured a positive fixed-profile amplitude in the same TESS sectors and limited its tail interpretation. Our separate scale test adds covariance and timing checks. We do not repeat a first-detection claim.