Search log: WASP-12 residual screen

Campaign: tess-wasp12-residual-01 Run date: 2026-09-24 UTC (runtime date) Outcome: bounded null; no candidate dossier. No external submission.

Falsifiable test#

For TIC 86396382 (WASP-12), screen two checksum-verified TESS SPOC 120-s light curves (Sectors 20 and 43) for negative flux excursions at least 5 robust-MAD sigmas below local median baselines, lasting at least two consecutive cadences, and outside a conservative ±0.08 orbital-phase window around the known WASP-12 b transit. The result would be a lead only if repeated by reasonable baseline scales/reductions and not explained by quality flags or known transits. The -5 MAD threshold is a descriptive screen, not a calibrated false-alarm probability.

Access and provenance#

• Archive: MAST public product downloads; source URLs and product dataURIs are in docs/tier1_pack/MASTER_MANIFEST.csv; transfer used the existing scoped [private Drive store] Drive location, one file at a time with rclone copyto (not sync). Scratch is [private path] and is disposable; no originals altered.
• Sector 20 product tess2019357164649-s0020-0000000086396382-0165-s_lc.fits: 1,926,720 bytes; manifest SHA-256 bf74a16f6e0c40b693a66de922e142d446cb44cee5bb7f26843062e436957f63; recomputed local SHA-256 matched.
• Sector 43 product tess2021258175143-s0043-0000000086396382-0214-s_lc.fits: 1,811,520 bytes; manifest SHA-256 e3d5c6f76884014ec1dec1eb60f04eaf734330a7abd8eef99141f49df03b2493; recomputed local SHA-256 matched.
• Both files are TESS SPOC light-curve FITS products (120 s in manifest). Sector 20 primary header: PROCVER=spoc-5.0.96-20230729, DATA_REL=73; Sector 43: PROCVER=spoc-5.0.45-20211006, DATA_REL=62. Header object TIC 86396382; header RA/Dec 97.6366528°, +29.6722962° (frame realization not independently verified). FITS table records TIMESYS=TDB, BJDREFI=2457000, BJDREFF=0; stored TIME is BJD−2457000 days, not a UTC date.
• Sector 20 UTC header dates: 2019-12-25 to 2020-01-20; usable stored TIME 1842.509510–1868.827130 (BJD-like 2458842.509510–2458868.827130). Sector 43 UTC dates: 2021-09-16 to 2021-10-11; TIME 2474.171742–2498.125471 (BJD-like 2459474.171742–2459498.125471).
• Runtime: Python 3.13.3; NumPy 2.5.3, SciPy 1.18.1, Astropy 8.0.1. Random seed 20260924 is declared in YAML; no stochastic computation was used.

Catalog and literature gate#

• NASA Exoplanet Archive live pscomppars snapshot queried 2026-09-24 for WASP-12 (format=json; no separately versioned release identifier was exposed in this query): select pl_name,pl_orbper,pl_tranmid,pl_trandur,disc_refname from pscomppars where hostname='WASP-12'. Returned WASP-12 b, period 1.09141890100 d, transit midpoint 2457607.51930500, duration 3.001 h, reference Hebb et al. 2009. Source URL: <https://exoplanetarchive.ipac.caltech.edu/TAP/sync?query=select%20pl_name,pl_orbper,pl_tranmid,pl_trandur,disc_refname%20from%20pscomppars%20where%20hostname%3D%27WASP-12%27&format=json>;.
• The transit phase is calculated from that archive period/midpoint, but may not model long-baseline transit timing/period evolution. ±0.08 phase was deliberately broad (±2.1 h), not a precision ephemeris fit.
• Web-search requests on 2026-09-24: WASP-12b transit ephemeris period 1.0914 TESS Sector 20 2019 and WASP-12 TESS Sector 20 unusual transit event light curve 2019 paper. Configured generic search service returned HTTP 402 (insufficient balance); these searches did not return results. No ADS, ExoFOP, VSX, or other literature/watchlist query succeeded in this run; those checks are not tested, not passed. The target is already a known transiting-planet host, so no novelty claim is in scope.

Screening and exclusions#

Excluded cadences include nonzero QUALITY and/or nonfinite/zero flux/time; exact per-reason breakdown was not performed. For each product, flux measured by SAP and PDCSAP separately at centered 1-, 2-, and 3-day running-median scales. Event snippets recur only in the broad known-transit phase window; no threshold crossing survived outside it in any of the six reduction/scale combinations. Counts are not independent events, not trials-corrected, and not detections. No individual excursion is retained as a lead.

Off-transit same-light-curve control (phase between 0.08 and 0.92; phase computed from archive ephemeris) contained 13,926 Sector-20 and 13,071 Sector-43 cadences. Robust fractional scatter (SAP, PDCSAP): S20 0.002145, 0.001957; S43 0.001935, 0.001911. These are descriptive noise controls; they are not a calibrated null distribution.

Artifact checks and omissions#

• Performed: quality-zero cadence selection; parallel SAP/PDCSAP and three baseline-window comparison; centroid columns MOM_CENTR1/2 were present and their values retained with screen rows; two temporally separated sectors; known transit phase veto.
• Not tested: cadence-level centroid/event correlation (centroid columns only retained, no correlation statistic); pixel-level localization, background/scattered light, pointing systematics, cosmic rays/hot pixels, nearby blends/background eclipsing binaries, independent pipeline/reduction or instrument, injection–recovery, calibrated correlated-noise false-alarm rates, current ADS/literature and ExoFOP/watchlist sweep.

Rejections and null results#

1. All -5 MAD snippets were rejected from lead status because they lay inside the deliberately broad phase window for cataloged WASP-12 b transits. This is not evidence for additional objects. Any transit-shape or timing claim would require current transit timing, pixel/centroid auditing, and independent reduction.
2. The proposed target/hypothesis is retained only as a documented bounded null: no out-of-window excursion met the declared threshold in these two SPOC sectors. Other sectors, cadences, targets, filters, and all other phenomena were not searched.

Reproduction#

From repository root with the recorded scratch files and Python environment:

[private path] tools\analyze_tess_residual.py [private path] --out reports\tess-wasp12-residual-01\sector20
[private path] tools\analyze_tess_residual.py [private path] --out reports\tess-wasp12-residual-01\sector43

The script enforces exact product basenames, byte lengths, and SHA-256 before reading FITS. Both selected products were successfully processed, producing screen.json and normalized_series.csv in each derived-output directory. Offline project regression test run from the worktree: python -m pytest -q -m 'not network' → 132 passed, 2 deselected (these are general project tests, not a calibration validation of this real-product screen). Source data remain only in scratch and may be deleted; downloaded source products are not checked into the repository.

Addendum (2026-09-24, later): runner re-run, calibration, catalogue cross-match#

• Re-run: python -m cygnus.campaign run campaigns/tess-wasp12-residual-01.yaml with the project venv (Python 3.13.3, NumPy 2.5.3, SciPy 1.18.1, Astropy 8.0.1). The spec now carries the exact ephemeris used (P = 1.09141890100 d, T0 = 2457607.51930500 BJD_TDB; the earlier spec's rounded 1.0914 d was never used by the code). Ledger runs #31 (fetch, checksums re-verified), #32 (screen), #33 (calibration), #34 (catalogue cross-match), all completed.
• Screen outputs reproduced exactly (byte-identical normalized series; identical 835/464 entries, 0 outside the window).
• Calibration (sign-flip null and injection–recovery; parameters in the spec; seed 20260924): results in sector*/calibration.json and the report addendum.
• Catalogue cross-match queries (ADQL, verbatim) and dated results are in the ledger prior_art table under target:WASP-12 and in runner/prior_art.json.
• Still not tested: centroid correlation, pixel-level background/blend, cosmic-ray/hot-pixel, independent reduction or instrument, ADS literature.