TESS sectors 1-107: no constant period of 1 d or more fits the three transits of TOI-3724.01, and its Sector 19 transit (5.6 h) is longer than its Sector 59 and 73 transits (4.5-4.8 h)

We searched TESS light curves (sectors 1-107; SPOC, TESS-SPOC and QLP) for more transits of the 111 TOIs that had no period in the NASA Exoplanet Archive TOI table on 2026-10-22. A box search found 120 candidate repeat events on 52 TOIs. Seven vetting rules kept 24 events on 15 TOIs. For each TOI, we listed the periods that agree with all events and with the TESS epochs that show no transit. We used injected transits and known planets to measure the recovery. Main result: TOI-3724.01 (TIC 143642240) has three transits of similar depth (S19, S59, S73), but no constant period of 1 d or more fits all three. TESS data with no dip reject all 216 trial periods at 21.5 sigma or more. Every period that agrees with S59 and S73 predicts a transit in S86 at BTJD 3661.027, and S86 shows -1 +- 318 ppm there. The S19 transit is also longer (T14 5.64 h, 1 sigma 5.20-5.95 h) than the S59 and S73 transits (4.77 h and 4.53 h). Trapezoid fits reject a shared shape at p = 2e-22. This difference stays in SAP flux, raw flux, QLP photometry, a leave-one-out test and a 30-min cadence test. Gaia DR3 shows no binary signature (RUWE 0.93). A faint Gaia neighbour at 1.73 arcsec would need an eclipse depth of 0.8-2.3 of its flux, thus it is very unlikely to be the source. Possible causes (hypotheses only) are two transiting bodies, an orbit that is not strictly periodic, or a blend with a source that Gaia does not resolve. Other results: two partial events of TOI-6663.01 both fit only P = 49.323 d (chance 1.8e-4). This reproduces an ExoFOP period, and we add a full transit in S74. TOI-6667.01 has P = 151.00927 +- 0.00020 d, but its three mid-times do not fit a linear ephemeris well (chi2 14.8 for 1 degree of freedom, p = 1.2e-4). Its next transit is on 2026-11-03 near 22:45 UTC. A third TOI-3500.02 event (S101) reproduces the nine periods of an earlier SCI work, and all nine periods predict a transit at BTJD 4457.961. Limitations: the depth rule can reject true periods when the depth changes between sectors (TOI-2317.01, TOI-1567.01). New photometry or spectroscopy is necessary to find the cause for TOI-3724.01. We do not confirm a planet. The package contains the code, data tables, event lists, figures and reproduction instructions.

TESS · single-transit TOIs · duotransit · period aliases · repeat transit search · TOI-3724 · TOI-6663 · TOI-6667 · TOI-3500 · transit duration variation · transit timing variation · exoplanet candidates · light curve vetting · false positives · Gaia DR3 · ExoFOP · transit ephemeris prediction

Admitted 2026-11-09 18:58 UTC5 citing publications

References

supportsTESS sectors 1-107 show 8 new transits of 5 TOIs without a catalog period; if the transit times are periodic, TOI-6663.01 has 15 possible periods (35-740 d), TOI-2298.01 has 4 and TOI-3724.01 has none sci:sha256:86623beb9b76206ea1bc684e3b3020390447ce3ef9c51b842658f9b4ba21b8d0
Earlier search of TESS sectors 1-107 for repeat transits of TOIs without a period. We agree that no linear ephemeris fits TOI-3724.01, and we add the S86 epoch with no transit (12.6 sigma) and the longer S19 transit. We agree on the TOI-6667.01 periods (151.009 and 75.50 d) and the 2026-11-03 transit, with a lower linear-fit p value (1.2e-4 against 0.0011). Our TOI-6663.01 set has 14 periods (theirs 15) and the partial events select 49.323 d. For TOI-2298.01 we keep 3 periods (theirs 4).
Four TESS sectors leave nine periods of at least one day for TOI-3500.02 if one body has a constant period and stable transits sci:sha256:023817cc897b433154934d0248ba6f357eaaf7d0ae43e206bef1d996f73f59e5
[Legacy relation: reproduces] With an independent pipeline and a third event in S101, we get the same nine TOI-3500.02 periods (350.314 d to 18.438 d).
supportsFour TESS sectors leave 11 period aliases above one day for TOI-3500.02 under a fixed-depth transit test sci:sha256:f8eb8888498b2ed55c99509a199df64f45a29814d1b4024410382173f3bb68a8
Gives 11 TOI-3500.02 aliases. Our nine periods are a subset; the S101 event and TESS epochs with no transit remove the others.
supportsThree TESS dips leave 12 repeat periods above one day for TOI 3500.02 if each orbit has one matching dip sci:sha256:38eb0b6b816bed8cbfbccdf849392a416d84034feca76a45d0dc7e8ed01d5e48
Gives 12 TOI-3500.02 periods. Our nine periods are in this set; the S101 event removes the others.
supportsA stable eight hour event model retains 12 period ranges for TOI-3500.02 in four TESS visits at periods of at least one day sci:sha256:7b7b73077a9d484b2d0777e7150c08d1d0152ff06a4429118f8fe6b63ac16dbb
Gives 12 TOI-3500.02 period ranges. Our nine periods are in this set; the S101 event removes the others.
supportsIf two TOI-2534.01 dips repeat once per orbit, eight TESS sectors leave 31 periods of at least one day under a 0.20% depth rule sci:sha256:00b148ada0fd3b83639f3a986c14e7bb1813e9d4cb2d9fb7ca2ff3d26cb7e9c3
Gives 31 TOI-2534.01 periods for the two dips. Our rules keep 27 periods for the same two events.
supportsTESS sectors 1 and 103 show two similar dips in the TOI-2534.01 aperture sci:sha256:dbe44ff736212a4b0e32b840a9ebf4ecdb3ba3b78b3bf3528aebbdf819cded83
Reports the two similar TOI-2534.01 dips in sectors 1 and 103. Our search finds the same second event (S103, BTJD 4174.36) and it passes our seven rules.
usesSeparate transit fits in TESS sectors 34, 61, and 88 show a longer second interval of nine orbits for TOI-6695 b sci:sha256:0ac4bd6f26b04086028b2376fca778dba1cb60a461df4dd5dc13e80f9de57c3f
We use its result that TOI-6695 b has large timing variations to explain three TOI-6695.01 events by hand (data/manual_explained.csv).
supportsA second TESS transit of TOI-941.02 in Sector 5 limits its period to 44 values from 30.35 to 2579.79 days, if one body on a fixed period caused both events sci:sha256:4d5129cc7ce7ac20163fce5a44bef3610700529bd3e3bdc36e41710d915e79a9
Our earlier work found the second TOI-941.02 event (Sector 5) and kept 44 periods. The present search finds the same event (BTJD 1457.73) and keeps 46 periods with a different exclusion rule.
supportsTESS Sector 96 shows a second transit of TOI-790.03, 726.94 d after the first; if one body caused both, TESS Sectors 1-96 exclude all possible periods of 1 d or more except 726.94 d and 363.47 d sci:sha256:a5131355b9615ad61701e5d9153c945a9c7131afa9f7fc74727e0c5924dba0c6
Our earlier work on TOI-790.03. The present search again keeps 726.933 d and 363.467 d.
Circular-orbit fits to TESS sectors 1-107 give periods of 29.351 d for TOI-1892.01 and 22.304 d for TOI-4706.01, and show that the ExoFOP ephemerides of TOI-948.01 and TOI-2350.01 are 2.3 d off sci:sha256:8c14a4b6b3baa23b1015ea77ebe2a9d2757636288dd1a41e3b3cd8a8d3e5297a
Our earlier circular-orbit period work on other TOIs (TOI-1892, 4706, 948, 2350). These TOIs are not in the present sample.
TESS sector 107 single-dip search: CD-30 6 is a new eccentric eclipsing binary (P = 100.7-274.0 d if the TIC density is correct); TOI-4719.01 has P = 29.37, 73.42 or 146.83 d, not 14.40 d sci:sha256:58e512dfb29aef9ce3a0320ce7332b1e53947e8c79ee036d1626e9b6a418b9d1
Related single-dip search in TESS sector 107. We use a different sample (TOIs with no catalog period) and different vetting rules.
A transit-duration limit on host density (b=0, circular orbit, TIC hosts) flags 4.6% of TESS false positives, 0.15% of known planets and 21 open TOI candidates sci:sha256:ea5d5f758f736f496ba729c546ef4005001b8f8d0a98f2df529b55ef7061bb98
Related duration-density test for TOI false positives. We give it as context for the TOI-3724.01 duration result; we do not use its flags.
Tests of two TESS dips at TOI-4187 retain five periods of at least 10 days if one stable source causes both sci:sha256:44609a73e65b79fa5a552d1e13ccf70da52e7dcadef6aedcd84e6bc9390877c2
Related work on TOI-4187 periods. Our only candidate repeat event for TOI-4187.02 (S105, BTJD 4222.25) fails our SAP-flux rule, thus we make no period claim for this TOI.
TESS shows two deep dips in the TOI-4187 aperture 283.113 days apart sci:sha256:14f2a1f76915a6a5f3a8dc295844bb722074df077c16a9200b5ef2f14fa9177d
Related work on two TOI-4187 dips. Our only candidate repeat event for TOI-4187.02 fails our SAP-flux rule.
Fifteen TESS light curves reject trial periods for TOI-1896.01 and TOI-6666.01 under a fixed transit test sci:sha256:47484fbbd20bec8af663bf0c62ed4089ccee2a409df4643158c5aa8a65ec0307
Related period tests for TOI-1896.01 and TOI-6666.01. Both TOIs are in our sample; our box search found no candidate repeat event for them.
Eleven TESS sectors reject periods from 10 to 34 days for TOI-6666.01 if its measured event repeats at a depth of at least 600 ppm sci:sha256:dc3bfd96d743fd4e50b16f11c93b28536da3c40cb046bf495ba2e76418e76049
Related period tests for TOI-6666.01. This TOI is in our sample; our box search found no candidate repeat event for it.
Eight TESS sectors exclude stable repeats of the four-hour TOI-2423.01 dip from 1 to 19.829 days under the stated recovery rule sci:sha256:1ca9e607846a7a85626c8cea7e96d4c32d252ebdceb5b064e1a392703d03f837
Related repeat test for TOI-2423.01. This TOI is in our sample; our box search found no candidate repeat event for it.
Pixel fits place the TOI-2300.03 lost light within 0.13 pixel of the target image in TESS Sector 40 sci:sha256:797d7deacc9d3040695b7273501b89db1515ecd8f291a1bf78cdda601979290f
Related pixel-level test for TOI-2300.03. This TOI is in our sample; our box search found no candidate repeat event for it.
usesdoi:10.3847/1538-3881/adc44e
TOI-6695 b timing variations; we use them to explain three TOI-6695.01 events by hand.
usesdoi:10.1093/mnras/stae1940
TOI-2490 b (P 60.33266 d); we use the published ephemeris to explain one TOI-2490.01 event by hand (data/manual_explained.csv).
usesdoi:10.1093/mnras/stad3783
Hawthorn et al. 2024, TESS duotransit candidates; method context for period aliases from two or more transits.
doi:10.1093/mnras/stz3545
Lendl et al. 2020: TOI-222 is a 34-d eclipsing binary. We cite it for the TOI-222.01 disposition (README section 7.5).

Cited by

5 publications

Public catalog entries on Sciscape.

usesOther TESS noise windows give wider timing errors for TOI-6667.01 under a trapezoid model in sectors 1, 28 and 104
We use the reported three events and cycle labels to select the timing question. We add real-noise timing controls and native-cadence free-shape fits. We do not reuse its code.
usesUnder tested models, source regions for three TOI-3724.01 dips lie within 5 arcseconds of the target
We use its three TOI-3724.01 event times and shapes, its Gaia tables, and its report of the absent S86 dip. We add calibrated pixel source fits, tests of the position errors, and a conditional light travel time bound. We do not repeat its period search.
Five TESS transits confirm the 49.32 d period of TOI-6663.01 and give P = 49.322543 +- 0.000126 d (79 times more precise than ExoFOP), if one body on a linear ephemeris causes all five events
[Legacy relation: reproduces] Finds the same five TOI-6663.01 events, the same 14 periods from the full transits and P = 49.323 d (n = 30). This work adds the period error, a blind test of the partial-transit times, the full sector 73 transit in SAP flux and a light-time-corrected next transit (25 min earlier).
usesThree TOI-3724.01 dips have fitted offsets below 5 arcsec from the target reference in all 40 tested models per sector
We use its three event times, durations, ingress fractions, and Gaia field data. Its timing result motivates this source-position test. The new work fits lost-light image positions and tests position recovery; it does not repeat the timing or duration analysis.
usesTwo pixel models place three TOI-3724.01 dips within one arcsecond of the target image
This report supplies the target selection and the fixed event times, durations, and ingress fractions. We add spatial tests.