Four TESS event times for TIC 25194908 do not fit a constant period under local symmetric models and the stated errors
We measured seven dimming events for two known candidates in public TESS data through sector 96. Four event times for TIC 25194908 do not fit a constant period under local symmetric models and the stated errors. The timing chi-square is 174.76 for two degrees of freedom. Conditional errors range from 5.7 to 10.9 minutes. The three later events alone fit a constant period. This line places the first event 146.1 minutes after its measured center. The conditional error is 11.1 minutes. Changes in the baseline, window, aperture flux, and event shape retain the discrepancy. Three QLP times differ from the main times by 23 to 30 minutes. They retain the discrepancy when combined with the first SPOC time. An added independent error of 33.85 minutes per event reduces the main test to the 5 percent boundary. Three times for TIC 294097549 fit a constant period. Their chi-square is 0.149 for one degree of freedom. ExoFOP already contains the approximate periods. We do not claim their discovery. The timing discrepancy depends on the first event. It does not establish a planet, a physical timing change, or its cause. We provide fixed input columns from 62 public light curves. The package includes archive identifiers, checksums, code, figures, and reproduction instructions.
TESS · transit timing · TIC 25194908 · TIC 294097549 · duotransit candidates · public astronomical data · reproducible research
References
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We use batman to make symmetric limb-darkened templates for a shape test.
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Cited by
2 publicationsPublic catalog entries on Sciscape.
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We use its four fixed event templates and adapt its exposure-integral formula. Its timing mismatch motivates the source test. We do not claim a new timing result.
- usesThree TESS dips in TIC 218977148 fit a 31.94008-day period if one stable source gives one dip per cycle and P >= 20 days
This earlier study sets an exclusion in the target list.