Hundreds of new periodic signals detected in the first year of $TESS$ with the $\mathtt{weirddetector}$

Abstract

We apply the $\mathtt{weirddetector}$, a nonparametric signal detection algorithm based on phase dispersion minimization, in a search for low duty-cycle periodic signals in the Transiting Exoplanet Survey Satellite ($TESS$) photometry. Our approach, in contrast to commonly used model-based approaches specifically for flagging transits, eclipsing binaries, or other similarly periodic events, makes minimal assumptions about the shape of a periodic signal, with the goal of finding "weird" signals of unexpected or arbitrary shape. In total, 248,301 $TESS$ sources from the first-year Southern sky survey are run through the $\mathtt{weirddetector}$, of which we manually inspect the top 21,500 for periodicity. To minimize false-positives, we here only report on the upper decile in terms of signal score, a sample for which we obtain 97% recall of $TESS$ eclipsing binaries and 62% of the TOIs. In our sample, we find 377 previously unreported periodic signals, for which we make a first-pass assignment that 26 are ultra-short periods ($<0.3$ d), 313 are likely eclipsing binaries, 28 appear planet-like, and 10 are miscellaneous signals.

Accepted to MNRAS, ref. MN-20-3245-MJ.R1. Data available at https://github.com/joheenc/woi_data . 09/23/20: edited Table 1 and Section 2.1; eliminated several previously known signals from ASAS-SN and VSX catalogs