Title

The First Post-Kepler Brightness Dips of KIC 8462852

Authors

Tabetha S. Boyajian, Louisiana State University
Roi Alonso, Instituto Astrofisico de Canarias
Alex Ammerman, University of Notre Dame
David Armstrong, University of Warwick
A. Asensio Ramos, Instituto Astrofisico de Canarias
K. Barkaoui, Université de Liège
Thomas G. Beatty, Pennsylvania State University
Z. Benkhaldoun, Université Cadi Ayyad
Paul Benni, American Association of Variable Star Observers
Rory O. Bentley, Louisiana State University
Andrei Berdyugin, Tuorlan observatorio
Svetlana Berdyugina, Kiepenheuer-Institut für Sonnenphysik
Serge Bergeron, American Association of Variable Star Observers
Allyson Bieryla, Harvard-Smithsonian Center for Astrophysics
Michaela G. Blain, Calvin University
Alicia Capetillo Blanco, American Association of Variable Star Observers
Eva H.L. Bodman, School of Earth and Space Exploration
Anne Boucher, Institut de Recherche sur les Exoplanètes
Mark Bradley, American Association of Variable Star Observers
Stephen M. Brincat, American Association of Variable Star Observers
Thomas G. Brink, University of California, Berkeley
John Briol, American Association of Variable Star Observers
David J.A. Brown, University of Warwick
J. Budaj, Astronomical Institute Slovak Academy of Sciences
A. Burdanov, Université de Liège
B. Cale, George Mason University
Miguel Aznar Carbo, American Association of Variable Star Observers
R. Castillo Garcia, American Association of Variable Star Observers
Wendy J. Clark, American Association of Variable Star Observers
Geoffrey C. Clayton, Louisiana State University
James L. Clem, Grove City College
Phillip H. Coker, American Association of Variable Star Observers
Evan M. Cook, Calvin University

Document Type

Article

Publication Date

1-20-2018

Abstract

We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in 2015 October, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1%-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor," which persist on timescales from several days to weeks. Our main results so far are as follows: (i) there are no apparent changes of the stellar spectrum or polarization during the dips and (ii) the multiband photometry of the dips shows differential reddening favoring non-gray extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale ≪1 μm, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process.

Publication Source (Journal or Book title)

Astrophysical Journal Letters

This document is currently not available here.

Share

COinS