A Transient Transit Signature Associated with the Young Star RIK-210

Abstract

We find transient, transit-like dimming events within the K2 time series photometry of the young star RIK-210 in the Upper Scorpius OB association. These dimming events are variable in depth, duration, and morphology. High spatial resolution imaging revealed the star is single, and radial velocity monitoring indicated that the dimming events can not be due to an eclipsing stellar or brown dwarf companion. Archival and follow-up photometry suggest the dimming events are transient in nature. The variable morphology of the dimming events suggests they are not due to a single, spherical body. The ingress of each dimming event is always shallower than egress, as one would expect for an orbiting body with a leading tail. The dimming events are periodic and synchronous with the stellar rotation. However, we argue it is unlikely the dimming events could be attributed to anything on the stellar surface based on the observed depths and durations. Variable obscuration by a protoplanetary disk is unlikely on the basis that the star is not actively accreting and lacks the infrared excess associated with an inner disk. Rather, we explore the possibilities that the dimming events are due to magnetospheric clouds, a transiting protoplanet surrounded by circumplanetary dust and debris, eccentric orbiting bodies undergoing periodic tidal disruption, or an extended field of dust or debris near the corotation radius.

accepted to ApJ, 25 pages, 19 figures, 4 tables

References in corpus (20)

• The K2 Mission: Characterization and Early results
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Optical Images of an Exosolar Planet 25 Light Years from Earth
• Improving PARSEC models for very low mass stars
• The Magnetic Fields of Classical T Tauri Stars
• Search for exoplanets with the radial-velocity technique: quantitative diagnostics of stellar activity
• Results of the ROTOR-program. II. The long-term photometric variability of weak-line T Tauri stars
• Influence of Stellar Multiplicity On Planet Formation. II. Planets Are Less Common in Multiple-Star Systems with Separations Smaller than 1500 AU
• CSI 2264: Characterizing Young Stars in NGC 2264 with Short-Duration, Periodic Flux Dips in their Light Curves
• New Pre-main-Sequence Stars in the Upper Scorpius Subgroup of Sco-Cen
• Detection of Stars within $\sim$0.8 arcseconds of Kepler Objects of Interest
• A Young Planet Search in Visible and IR Light: DN Tau, V836 Tau, and V827 Tau
• Stellar activity as noise in exoplanet detection II. Application to M dwarfs
• Resolving the planet-hosting inner regions of the LkCa 15 disk
• Magnetospheric Gap and Accumulation of Giant Planets Close to the Star
• Formation of starspots in self-consistent global dynamo models: Polar spots on cool stars
• On Sunspot and Starspot Lifetimes
• The Relation between the Transit Depths of KIC 12557548b & the Stellar Rotation Period
• Star Spot Induced Radial Velocity Variability in LkCa 19
• XMM-Newton observations of the complex spin pulse of the intermediate polar PQ~Geminorum

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• More Rapidly Rotating PMS M Dwarfs with Light Curves Suggestive of Orbiting Clouds of Material
• On the Detection of Exomoons Transiting Isolated Planetary-Mass Objects
• Ohmic heating of asteroids around magnetic stars
• Highly structured inner planetary system debris around the intermediate age Sun-like star TYC 8830 410 1
• Evidence for Centrifugal Breakout around the Young M Dwarf TIC 234284556
• Evidence for planetary hypothesis for PTFO 8-8695b with five-year optical/infrared monitoring observations
• Clumpy dust rings around non-accreting young stars
• PTFO 8-8695: Two Stars, Two Signals, No Planet
• Pleiades or Not? Resolving the Status of the Lithium Rich M Dwarfs HHJ339 and HHJ430
• YETI follow-up observations of the T Tauri star CVSO30 with transit-like dips