WD 1145+017 Photometric Observations During 8 Months of High Activity

Abstract

WD 1145+017 was observed from 2015 November to 2016 July for the purpose of characterizing transit behavior of the white dwarf by dust clouds thought to be produced by fragments of an asteroid in close orbit with the star. Fortuitously, most of these observations were carried out during a time when the overall `dip' activity was dramatically enhanced over that during its discovery with Kepler K2. By the end of our reported observations the dip activity had declined to a level close to its K2 discovery state. Three notable events were observed. In 2016 January a large number of dust clouds appeared that had an orbital period of 4.4912 hours, and this event also marked the end of a 3-month interval dominated by the K2 `A' period. The second event was a 2016 April 21 appearance of four dip features with drift lines in a waterfall diagram (date vs. phase) that diverged from their origin date, at a location away from the `A' asteroid, and which lasted for two weeks. The third event was the sudden appearance of a dip feature with a period of 4.6064 hours, which is essentially the same as the K2 `B' period. The evolution of dip shape, depth, and total fade amount provide constraints on dust production and loss mechanisms. Collisions can account for the sudden appearance of dust clouds, and the sudden increase in dust amount, but another mechanism for continual dust production is also required.

13 pages, 15 figures, MNRAS (2016), approved for publication

References in corpus (8)

• The K2 Mission: Characterization and Early results
• The frequency of planetary debris around young white dwarfs
• A gaseous metal disk around a white dwarf
• The Chemical Composition of an Extrasolar Minor Planet
• Formation of planetary debris discs around white dwarfs I: Tidal disruption of an extremely eccentric asteroid
• Debris Disks Around White Dwarfs: The DAZ Connection
• The frequency and infrared brightness of circumstellar discs at white dwarfs
• Variable Emission from a Gaseous Disc around a Metal-Polluted White Dwarf

Cited by in corpus (17)

• Likely Transiting Exocomets Detected by Kepler
• Numerical Simulations of Collisional Cascades at the Roche Limits of White Dwarf Stars
• Explaining the variability of WD 1145+017 with simulations of asteroid tidal disruption
• The occurrence of planets and other substellar bodies around white dwarfs using K2
• The Fate of Exomoons in White Dwarf Planetary Systems
• A dearth of small particles in the transiting material around the white dwarf WD 1145+017
• Modeling of the Variable Circumstellar Absorption Features of WD 1145+017
• Detections and Constraints on White Dwarf Variability from Time-Series GALEX Observations
• WD 1145+017: Optical Activity During 2016-2017 and Limits on the X-Ray Flux
• Binary star influence on post-main-sequence multi-planet stability
• Deep Long Asymmetric Occultation in EPIC 204376071
• Orbital relaxation and excitation of planets tidally interacting with white dwarfs
• The Random Transiter -- EPIC 249706694/HD 139139
• Shallow Ultraviolet Transits of WD 1145+017
• Magnetospherically-trapped dust and a possible model for the unusual transits at WD 1145+017
• The critical binary star separation for a planetary system origin of white dwarf pollution
• The unstable fate of the planet orbiting the A-star in the HD 131399 triple stellar system