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Monthly Notices of the Royal Astronomical Society | 2016

Planet Hunters IX. KIC 8462852 - Where's the flux?

Tabetha S. Boyajian; Daryll LaCourse; Saul Rappaport; Daniel C. Fabrycky; Debra A. Fischer; Davide Gandolfi; Grant M. Kennedy; H. Korhonen; Michael C. Liu; A. Moór; Katalin Oláh; K. Vida; Mark C. Wyatt; William M. J. Best; John M. Brewer; F. Ciesla; B. Csak; H. J. Deeg; Trent J. Dupuy; G. Handler; Kevin Heng; Steve B. Howell; S. T. Ishikawa; József Kovács; T. Kozakis; L. Kriskovics; J. Lehtinen; Chris Lintott; Stuart Lynn; D. Nespral

TSB acknowledges support provided through NASA grant ADAP12-0172 and ADAP14-0245. MCW and GMK acknowledge the support of the European Union through ERC grant number 279973. The authors acknowledge support from the Hungarian Research Grants OTKA K-109276, OTKA K-113117, the Lendulet-2009 and Lendulet-2012 Program (LP2012-31) of the Hungarian Academy of Sciences, the Hungarian National Research, Development and Innovation Office – NKFIH K-115709, and the ESA PECS Contract No. 4000110889/14/NL/NDe. This work was supported by the Momentum grant of the MTA CSFK Lendulet Disc Research Group. GH acknowledges support by the Polish NCN grant 2011/01/B/ST9/05448. Based on observations made with the NOT, operated by the Nordic Optical Telescope Scientific Association at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. This research made use of The DASCH project; we are also grateful for partial support from NSF grants AST-0407380, AST-0909073, and AST-1313370. The research leading to these results has received funding from the European Communitys Seventh Framework Programme (FP7/2007-2013) under grant agreements no. 269194 (IRSES/ASK) and no. 312844 (SPACEINN). We thank Scott Dahm, Julie Rivera, and the Keck Observatory staff for their assistance with these observations. This research was supported in part by NSF grant AST-0909222 awarded to M. Liu. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. KS gratefully acknowledges support from Swiss National Science Foundation Grant PP00P2_138979/1. HJD and DN acknowledge support by grant AYA2012-39346-C02-02 of the Spanish Secretary of State for R&D&i (MINECO). This paper makes use of data from the first public release of the WASP data (Butters et al. 2010) as provided by the WASP consortium and services at the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, and NEOWISE, which is a project of the Jet Propulsion Laboratory/California Institute of Technology. WISE and NEOWISE are funded by the National Aeronautics and Space Administration. This research made use of the SIMBAD and VIZIER Astronomical Databases, operated at CDS, Strasbourg, France (http://cdsweb.u-strasbg.fr/), and of NASAs Astrophysics Data System.


The Astronomical Journal | 2016

Kepler Eclipsing Binary Stars. VII. The Catalog of Eclipsing Binaries Found in the Entire Kepler Data Set

Brian Kirk; Kyle E. Conroy; Andrej Prsa; Michael Abdul-Masih; Angela Kochoska; G. Matijevic; Kelly Hambleton; S. Bloemen; Tabetha S. Boyajian; Laurance R. Doyle; Benjamin J. Fulton; Abe J. Hoekstra; Kian J. Jek; Stephen R. Kane; Veselin Kostov; David W. Latham; Tsevi Mazeh; Jerome A. Orosz; Joshua Pepper; Billy Quarles; Darin Ragozzine; Avi Shporer; J. Southworth; Keivan G. Stassun; Susan E. Thompson; William F. Welsh; Eric Agol; A. Derekas; Jonathan Devor; Debra A. Fischer

The primary Kepler Mission provided nearly continuous monitoring of ~200,000 objects with unprecedented photometric precision. We present the final catalog of eclipsing binary systems within the 105 deg^2 Kepler field of view. This release incorporates the full extent of the data from the primary mission (Q0-Q17 Data Release). As a result, new systems have been added, additional false positives have been removed, ephemerides and principal parameters have been recomputed, classifications have been revised to rely on analytical models, and eclipse timing variations have been computed for each system. We identify several classes of systems including those that exhibit tertiary eclipse events, systems that show clear evidence of additional bodies, heartbeat systems, systems with changing eclipse depths, and systems exhibiting only one eclipse event over the duration of the mission. We have updated the period and galactic latitude distribution diagrams and included a catalog completeness evaluation. The total number of identified eclipsing and ellipsoidal binary systems in the Kepler field of view has increased to 2878, 1.3% of all observed Kepler targets. An online version of this catalog with downloadable content and visualization tools is maintained athttp://keplerEBs.villanova.edu.


The Astrophysical Journal | 2013

Planet Hunters. V. A Confirmed Jupiter-size Planet in the Habitable Zone and 42 Planet Candidates from the Kepler Archive Data

Ji Wang; Debra A. Fischer; Tabetha S. Boyajian; Justin R. Crepp; Megan E. Schwamb; Chris J. Lintott; Kian J. Jek; Arfon M. Smith; Michael Parrish; Kevin Schawinski; Joseph R. Schmitt; Matthew J. Giguere; John M. Brewer; Stuart Lynn; Robert Simpson; Abe J. Hoekstra; Thomas Lee Jacobs; Daryll LaCourse; Hans Martin Schwengeler; Mike Chopin; Rafal Herszkowicz

We report the latest Planet Hunter results, including PH2 b, a Jupiter-size (R PL = 10.12 ? 0.56 R ?) planet orbiting in the habitable zone of a solar-type star. PH2 b was elevated from candidate status when a series of false-positive tests yielded a 99.9% confidence level that transit events detected around the star KIC?12735740 had a planetary origin. Planet Hunter volunteers have also discovered 42 new planet candidates in the Kepler public archive data, of which 33 have at least 3 transits recorded. Most of these transit candidates have orbital periods longer than 100?days and 20 are potentially located in the habitable zones of their host stars. Nine candidates were detected with only two transit events and the prospective periods are longer than 400?days. The photometric models suggest that these objects have radii that range between those of Neptune and Jupiter. These detections nearly double the number of gas-giant planet candidates orbiting at habitable-zone distances. We conducted spectroscopic observations for nine of the brighter targets to improve the stellar parameters and we obtained adaptive optics imaging for four of the stars to search for blended background or foreground stars that could confuse our photometric modeling. We present an iterative analysis method to derive the stellar and planet properties and uncertainties by combining the available spectroscopic parameters, stellar evolution models, and transiting light curve parameters, weighted by the measurement errors. Planet Hunters is a citizen science project that crowd sources the assessment of NASA Kepler light curves. The discovery of these 43 planet candidates demonstrates the success of citizen scientists at identifying planet candidates, even in longer period orbits with only two or three transit events.


The Astronomical Journal | 2014

Planet hunters. VI. An independent characterization of KOI-351 and several long period planet candidates from the Kepler archival data

Joseph R. Schmitt; Ji Wang; Debra A. Fischer; Kian J. Jek; John C. Moriarty; Tabetha S. Boyajian; Megan E. Schwamb; Chris J. Lintott; Stuart Lynn; Arfon M. Smith; Michael Parrish; Kevin Schawinski; Robert Simpson; Daryll LaCourse; Mark R. Omohundro; Troy Winarski; Samuel Jon Goodman; Tony Jebson; Hans Martin Schwengeler; David A. Paterson; Johann Sejpka; Ivan Terentev; Tom Jacobs; Nawar Alsaadi; Robert C. Bailey; Tony Ginman; Pete Granado; Kristoffer Vonstad Guttormsen; Franco Mallia; Alfred L. Papillon

We report the discovery of 14 new transiting planet candidates in the Kepler field from the Planet Hunters citizen science program. None of these candidates overlapped with Kepler Objects of Interest (KOIs) at the time of submission. We report the discovery of one more addition to the six planet candidate system around KOI-351, making it the only seven planet candidate system from Kepler. Additionally, KOI-351 bears some resemblance to our own solar system, with the inner five planets ranging from Earth to mini-Neptune radii and the outer planets being gas giants; however, this system is very compact, with all seven planet candidates orbiting


Monthly Notices of the Royal Astronomical Society | 2018

Likely transiting exocomets detected by Kepler

S. Rappaport; Andrew Vanderburg; Thomas Lee Jacobs; Daryll LaCourse; J. M. Jenkins; Adam L. Kraus; Aaron C. Rizzuto; D. W. Latham; Allyson Bieryla; M. Lazarevic; A. Schmitt

\lesssim 1


The Astrophysical Journal | 2013

KIC 9406652: AN UNUSUAL CATACLYSMIC VARIABLE IN THE KEPLER FIELD OF VIEW*

Douglas R. Gies; Zhao Guo; Steve B. Howell; Martin Still; Tabetha S. Boyajian; Abe J. Hoekstra; Kian J. Jek; Daryll LaCourse; Troy Winarski

AU from their host star. A Hill stability test and an orbital integration of the system shows that the system is stable. Furthermore, we significantly add to the population of long period transiting planets; periods range from 124-904 days, eight of them more than one Earth year long. Seven of these 14 candidates reside in their host stars habitable zone.


arXiv: Earth and Planetary Astrophysics | 2018

Single Transits and Eclipses Observed by K2

Daryll LaCourse; Thomas Lee Jacobs

We present the first good evidence for exocomet transits of a host star in continuum light in data from the Kepler mission. The Kepler star in question, KIC 3542116, is of spectral type F2V and is quite bright at Kp = 10. The transits have a distinct asymmetric shape with a steeper ingress and slower egress that can be ascribed to objects with a trailing dust tail passing over the stellar disk. There are three deeper transits with depths of ≃ 0.1% that last for about a day, and three that are several times more shallow and of shorter duration. The transits were found via an exhaustive visual search of the entire Kepler photometric data set, which we describe in some detail. We review the methods we use to validate the Kepler data showing the comet transits, and rule out instrumental artefacts as sources of the signals. We fit the transits with a simple dust-tail model, and find that a transverse comet speed of ∼35-50 km s-1 and a minimum amount of dust present in the tail of ∼ 1016 g are required to explain the larger transits. For a dust replenishment time of ∼10 days, and a comet lifetime of only ∼300 days, this implies a total cometary mass of ≳ 3 × 1017 g, or about the mass of Halleys comet. We also discuss the number of comets and orbital geometry that would be necessary to explain the six transits detected over the four years of Kepler prime-field observations. Finally, we also report the discovery of a single comet-shaped transit in KIC 11084727 with very similar transit and host-star properties.


The Astrophysical Journal | 2018

Occultations from an Active Accretion Disk in a 72-day Detached Post-Algol System Detected by K2

G. Zhou; S. Rappaport; L. A. Nelson; C. X. Huang; A. Senhadji; Joseph E. Rodriguez; Andrew Vanderburg; Samuel N. Quinn; Christian I. Johnson; David W. Latham; Guillermo Torres; Bruce L. Gary; T. G. Tan; Marshall C. Johnson; Jennifer Burt; Martti H. Kristiansen; Thomas Lee Jacobs; Daryll LaCourse; H. M. Schwengeler; I. Terentev; Allyson Bieryla; Gilbert A. Esquerdo; Perry L. Berlind; M. Calkins; J. Bento; William D. Cochran; M. Karjalainen; A. Hatzes; R. Karjalainen; B. Holden

KIC 9406652 is a remarkable variable star in the Kepler field of view that shows both very rapid oscillations and long term outbursts in its light curve. We present an analysis of the light curve over quarters 1-15 and new spectroscopy that indicates that the object is a cataclysmic variable with an orbital period of 6.108 hr. However, an even stronger signal appears in the light curve periodogram for a shorter period of 5.753 hr, and we argue that this corresponds to the modulation of flux from the hot spot region in a tilted, precessing disk surrounding the white dwarf star. We present a preliminary orbital solution from radial velocity measurements of features from the accretion disk and the photosphere of the companion. We use a Doppler tomography algorithm to reconstruct the disk and companion spectra, and we also consider how these components contribute to the objects spectral energy distribution from ultraviolet to infrared wavelengths. This target offers us a remarkable opportunity to investigate disk processes during the high mass transfer stage of evolution in cataclysmic variables.


The Astrophysical Journal | 2016

YOUNG “DIPPER” STARS IN UPPER SCO AND OPH OBSERVED BY K2

M. Ansdell; E. Gaidos; S. Rappaport; Thomas Lee Jacobs; Daryll LaCourse; Kian J. Jek; Andrew W. Mann; Mark C. Wyatt; Grant M. Kennedy; J. P. Williams; Tabetha S. Boyajian

Photometric survey data from the Kepler mission have been used to discover and characterize thousands of transiting exoplanet and eclipsing binary (EB) systems. These discoveries have enabled empirical studies of occurrence rates which reveal that exoplanets are ubiquitous and found in a wide variety of system architectures and physical compositions. Because the detection strategy of these missions is most sensitive to short orbital periods, the vast majority of these objects reside within 1 AU of their host star. Although other detection techniques have successfully identified exoplanets at wider orbits beyond the snow lines of their respective host stars (e.g., radial velocity, microlensing, direct imaging), occurrence rates within this population remain poorly constrained. As such, identifying long period objects (LPOs) from archival Kepler and K2 data is valuable from both a statistical and theoretical standpoint, particularly for massive gas giants which are thought to heavily influence the formation and evolution dynamics of their respective systems. Here we present a catalog of 164 single transit and eclipse candidates detected during a comprehensive survey of all currently available K2 data.


The Astrophysical Journal | 2016

ZODIACAL EXOPLANETS IN TIME (ZEIT). I. A NEPTUNE-SIZED PLANET ORBITING AN M4.5 DWARF IN THE HYADES STAR CLUSTER

Andrew W. Mann; Eric Gaidos; Gregory N. Mace; Marshall C. Johnson; Brendan P. Bowler; Daryll LaCourse; Thomas Lee Jacobs; Andrew Vanderburg; Adam L. Kraus; Kyle Kaplan; Daniel T. Jaffe

Disks in binary systems can cause exotic eclipsing events. MWC 882 (BD-22 4376, EPIC 225300403) is such a disk-eclipsing system identified from observations during Campaign 11 of the K2 mission. We propose that MWC 882 is a post-Algol system with a B7 donor star of mass

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Ji Wang

California Institute of Technology

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