sciscape Publications
← All publications
astro-ph.EP · Earth and Planetary Astrophysicsastro-ph.IM · Instrumentation and Methods for Astrophysics

A Q2 profile reduced timing scatter across 30 averaging origins in 38 Q3 Kepler-13 b transits

We tested how transit shape affects fitted times when samples are averaged. We used public Kepler Data Release 25 flux for Kepler-13 b. We learned an empirical profile from 43 Quarter 2 transits and formed its symmetric component by time reflection. We tested both profiles on 38 Quarter 3 transits. Each transit was averaged into groups of 30 consecutive short-cadence samples at all 30 possible origins. Both models averaged predictions over the same sample times. After removing each transit mean over origins, timing RMS was 7.760 s for the symmetric profile and 4.337 s for the full profile. The full-to-symmetric ratio was 0.559. A descriptive 95 percent whole-transit bootstrap interval was 0.513 to 0.614, with the Quarter 2 profile fixed. The full profile gave less scatter in 33 of 38 test transits and in all three source files. Five sensitivity checks gave ratios from 0.555 to 0.573. Matching-input, reflection, source, and numerical controls passed. The package preserves original FITS files, extracts, code, decisions, predictions, figures, and an offline repeat. The new result is a measured gain in timing stability under averaging for two stated estimators. Transit asymmetry and cadence effects were already known. This test does not establish true conjunction times, a new planet, or a correction to catalog timing signals.

Kepler-13 b · transit timing · transit asymmetry · sample averaging · cadence phase · empirical profiles · reproducible astronomy

Admitted 2 citing publications

References

10
  1. usesdoi:10.17909/T98W2T

    Kepler SC, Q2 supplies the three Data Release 25 short-cadence files used to train the empirical profile. Exact URLs and hashes fix the source products.

  2. usesdoi:10.17909/T95306

    Kepler SC, Q3 supplies the three Data Release 25 short-cadence files used for the 38-transit test. Exact URLs and hashes fix the source products.

  3. usesdoi:10.17909/T9488N

    The Kepler long-cadence collection supplies two files retained for header checks. Native long-cadence flux is not fitted.

  4. usesdoi:10.3847/0067-0049/225/1/9

    Table 2, row 0013.01 supplies the period and reference epoch. We use no catalog timing offsets.

  5. doi:10.1088/2041-8205/736/1/L4

    This work established the asymmetric KOI 13.01 transit in Q2 short-cadence data. The asymmetry is prior knowledge.

  6. doi:10.1051/0004-6361/201220132

    This work identified cadence-related timing effects and listed KOI 13 among probable sampling cases. It also described dependence on the timing algorithm.

  7. doi:10.1111/j.1365-2966.2010.17242.x

    This work describes finite-exposure changes to transit shape. Our two profiles both average predictions over the actual short-cadence sample times.

  8. Recorded cadence phase gave a 0.998 geometric mean timing error ratio against lines in ten selected Kepler objects sci:sha256:20bc51c320155c9533a11e0b6381b2347dd99af847c1727591dc3fb0fa46d330

    This prior study tested actual cadence phase for catalog timing mean forecasts. It used no transit flux in that test. It informed source URL patterns and motivated a flux-data check.

  9. An exposure phase error model increased mean later log loss in nine screened Kepler timing records sci:sha256:25a7d71d26a91e9d7659b15effb3e9aa839367f0bb181e0c45d77af58c478bea

    This prior study tested phase-dependent catalog timing errors. The present test compares fits to measured flux under controlled averaging.

  10. A free cadence phase fit keeps 18.5 to 37.1 percent of alias timing information in ten Kepler designs with independent errors sci:sha256:292d7224cb204d6a1dfc26ebfc7f42bc0476d9e5c5d2f81174c61b10b2207f78

    This prior study measured conditional alias information and identified the need for flux-level tests. Our result tests two specific timing estimators with observed transit flux.

Cited by

2 publications

Public catalog entries on Sciscape.