TESS sector 82 shows a second transit of the Kepler single-transit candidate KIC 10284575; Kepler and TESS data permit only six periods from 712 to 4983 days
Many long-period planet candidates in Kepler data have only one transit, so their period is not known. TESS observed the Kepler field again in 2019-2024 (sectors 14-83). We searched TESS light curves (SPOC, TESS-SPOC, QLP and own TESScut photometry for 364 slots without a pipeline light curve) of 80 Kepler stars with single-transit or double-transit candidates from four catalogues (Kawahara & Masuda 2019; Foreman-Mackey et al. 2016; Uehara et al. 2016; Herman et al. 2019). We used Kepler-fitted trapezoid templates, a noise-calibrated matched filter, a Gaia-based dilution model and 4524 injections. KIC 10284575 (KOI-3210, Tmag 11.6) shows a second transit on 2024-09-03 with the same depth (0.50-0.58%) and duration (25.7 +- 0.7 h) as its Kepler event of 2011-01-12. Aperture, sky, comparison-star and difference-image tests put the flux loss on the target, and the Kepler centroid puts the source within about 1 arcsec. Kepler and TESS coverage reject all periods 4983.43/n except n = 1-5 and 7 (4983, 2492, 1661, 1246, 997 and 712 d). The companion radius is 1.07 R_Jup; it can be a temperate giant planet, a brown dwarf or a low-mass star. TESS also shows no transit at the epoch that the published 494.44-d period of Kepler-1704 b predicts (9.4 sigma), in agreement with its 988.88-d RV period. Over all single-transit candidates, TESS had SNR >= 10 sensitivity to the Kepler depth for only 3 of 51 stars. The published period estimates predict 0.19 (KM19), 0.49 (H19), 0.14 (FM16) and 0.00 (U16) TESS detections; we found 1 (KIC 10284575, a KM19 entry). This agrees with the estimates but has low power. Limitations: the TESS event occurs during scattered light at the end of a sector and only QLP and own photometry cover it; the companion mass is unknown; the dilution model is approximate.
Kepler · TESS · single transit · long-period planet · KIC 10284575 · KOI-3210 · Kepler-1704 b · period aliases · injection-recovery · cold giant planets
References
6- uses, reviewshttps://arxiv.org/abs/1904.04980
Kawahara & Masuda 2019 single/double-transit catalogue and period estimates; TESS rejects their 494.44-d period for KOI-375.01 and finds a second transit of KIC 10284575.
- uses, reviewshttps://arxiv.org/abs/1607.08237
Foreman-Mackey et al. 2016 single-transit candidates and period posteriors.
- uses, reviewshttps://arxiv.org/abs/1602.07848
Uehara et al. 2016 single-transit events (source of the KIC 10284575 event).
- uses, reviewshttps://arxiv.org/abs/1901.01974
Herman et al. 2019 long-period candidates and period estimates.
- supportshttps://ui.adsabs.harvard.edu/abs/2021AJ....162..154D/abstract
Dalba et al. 2021 RV period of Kepler-1704 b (988.88 d); TESS data reject the half period.
- useshttps://ui.adsabs.harvard.edu/abs/2019AJ....158..138S/abstract
TIC v8 stellar parameters and TESS magnitude relation.
Cited by
2 publicationsPublic catalog entries on Sciscape.
- TESS data from 2018 to 2026 show repeat events for 36 of 164 K2 single-transit candidates, give one period for 6 systems, and limit TOI-5560.01 (EPIC 211924561) to 70.25 or 140.49 days
Related campaign study of Kepler single transits with TESS.
- TESS data to sector 107 show repeat transits for six single-transit TOIs with no published period and limit the periods of 58 other single-transit TOIs
A prior campaign publication found a TESS second transit of one Kepler single-transit candidate; we apply a similar idea to all period-zero TOIs.