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The Astrophysical Journal | 2013

Planet Hunters: A Transiting Circumbinary Planet in a Quadruple Star System

Megan E. Schwamb; Jerome A. Orosz; Joshua A. Carter; William F. Welsh; Debra A. Fischer; Guillermo Torres; Andrew W. Howard; Justin R. Crepp; William C. Keel; Chris J. Lintott; Nathan A. Kaib; Dirk Terrell; Robert Gagliano; Kian J. Jek; Michael Parrish; Arfon M. Smith; Stuart Lynn; Robert J. Simpson; Matthew J. Giguere; Kevin Schawinski

We report the discovery and confirmation of a transiting circumbinary planet (PH1b) around KIC 4862625, an eclipsing binary in the Kepler field. The planet was discovered by volunteers searching the first six Quarters of publicly available Kepler data as part of the Planet Hunters citizen science project. Transits of the planet across the larger and brighter of the eclipsing stars are detectable by visual inspection every ~137 days, with seven transits identified in Quarters 1-11. The physical and orbital parameters of both the host stars and planet were obtained via a photometric-dynamical model, simultaneously fitting both the measured radial velocities and the Kepler light curve of KIC 4862625. The 6.18 ± 0.17 R_⊕ planet orbits outside the 20 day orbit of an eclipsing binary consisting of an F dwarf (1.734 ± 0.044 R_☉, 1.528 ± 0.087 M_☉) and M dwarf (0.378 ± 0.023 R_☉, 0.408 ± 0.024 M_☉). For the planet, we find an upper mass limit of 169 M_⊕ (0.531 Jupiter masses) at the 99.7% confidence level. With a radius and mass less than that of Jupiter, PH1b is well within the planetary regime. Outside the planets orbit, at ~1000 AU, a previously unknown visual binary has been identified that is likely bound to the planetary system, making this the first known case of a quadruple star system with a transiting planet.


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.


Monthly Notices of the Royal Astronomical Society | 2014

Galaxy Zoo: CANDELS barred discs and bar fractions

Brooke Simmons; Thomas Melvin; Chris J. Lintott; Karen L. Masters; Kyle W. Willett; William C. Keel; Rebecca J. Smethurst; Edmond Cheung; Robert C. Nichol; Kevin Schawinski; Michael J. Rutkowski; J. Kartaltepe; Eric F. Bell; Kevin R. V. Casteels; Christopher J. Conselice; Omar Almaini; Henry C. Ferguson; L. Fortson; William G. Hartley; Dale D. Kocevski; Anton M. Koekemoer; Daniel H. McIntosh; Alice Mortlock; Jeffrey A. Newman; Jamie R. Ownsworth; Steven P. Bamford; Tomas Dahlen; Sandra M. Faber; Steven L. Finkelstein; A. Fontana

The formation of bars in disk galaxies is a tracer of the dynamical maturity of thepopulation. Previous studies have found that the incidence of bars in disks decreasesfrom the local Universe to z ∼ 1, and by z > 1 simulations predict that bar featuresin dynamically mature disks should be extremely rare. Here we report the discoveryof strong barred structures in massive disk galaxies at z ∼ 1.5 in deep rest-frameoptical images from CANDELS. From within a sample of 876 disk galaxies identifiedby visual classification in Galaxy Zoo, we identify 123 barred galaxies. Selecting a sub-sample within the same region of the evolving galaxy luminosity function (brighterthan L), we find that the bar fraction across the redshift range 0.5 ≤ z ≤ 2 (fbar =10.7+6.3−3.5% after correcting for incompleteness) does not significantly evolve.We discussthe implications of this discovery in the context of existing simulations and our currentunderstanding of the way disk galaxies have evolved over the last 11 billion years.


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 Astrophysical Journal | 2014

Planet Hunters. VII. Discovery of a New Low-mass, Low-density Planet (PH3 C) Orbiting Kepler-289 with Mass Measurements of Two Additional Planets (PH3 B and D)

Joseph R. Schmitt; Eric Agol; Katherine M. Deck; Leslie A. Rogers; J. Zachary Gazak; Debra A. Fischer; Ji Wang; Matthew J. Holman; Kian J. Jek; Charles Margossian; Mark R. Omohundro; Troy Winarski; John M. Brewer; Matthew J. Giguere; Chris J. Lintott; Stuart Lynn; Michael Parrish; Kevin Schawinski; Megan E. Schwamb; Robert Simpson; Arfon M. Smith

We report the discovery of one newly confirmed planet (P = 66.06 days, R_P = 2.68 ± 0.17 R_⊕) and mass determinations of two previously validated Kepler planets, Kepler-289 b (P = 34.55 days, R_P = 2.15 ± 0.10 R_⊕) and Kepler-289-c (P = 125.85 days, R_P = 11.59 ± 0.10 R_⊕), through their transit timing variations (TTVs). We also exclude the possibility that these three planets reside in a 1:2:4 Laplace resonance. The outer planet has very deep (~1.3%), high signal-to-noise transits, which puts extremely tight constraints on its host stars stellar properties via Keplers Third Law. The star PH3 is a young (~1 Gyr as determined by isochrones and gyrochronology), Sun-like star with M_* = 1.08 ± 0.02 M_☉, R_* = 1.00 ± 0.02 R_☉, and T_(eff) = 5990 ± 38 K. The middle planets large TTV amplitude (~5 hr) resulted either in non-detections or inaccurate detections in previous searches. A strong chopping signal, a shorter period sinusoid in the TTVs, allows us to break the mass-eccentricity degeneracy and uniquely determine the masses of the inner, middle, and outer planets to be M = 7.3 ± 6.8 M_⊕, 4.0 ± 0.9 M_⊕, and M = 132 ± 17 M_⊕, which we designate PH3 b, c, and d, respectively. Furthermore, the middle planet, PH3 c, has a relatively low density, ρ = 1.2 ± 0.3 g cm^(–3) for a planet of its mass, requiring a substantial H/He atmosphere of 2.1^(+0.8)_(-0.3)% by mass, and joins a growing population of low-mass, low-density planets.


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


The Astronomical Journal | 2013

PLANET HUNTERS: NEW KEPLER PLANET CANDIDATES FROM ANALYSIS OF QUARTER 2

Chris J. Lintott; Megan E. Schwamb; Charlie Sharzer; Debra A. Fischer; John M. Brewer; Matthew J. Giguere; Stuart Lynn; Michael Parrish; Natalie M. Batalha; Steve Bryson; Jon M. Jenkins; Darin Ragozzine; Jason F. Rowe; Kevin Schwainski; Robert Gagliano; Joe Gilardi; Kian J. Jek; Jari-Pekka Pääkkönen; Tjapko Smits

\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.


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

We present new planet candidates identified in NASA Kepler Quarter 2 public release data by volunteers engaged in the Planet Hunters citizen science project. The two candidates presented here survive checks for false positives, including examination of the pixel offset to constrain the possibility of a background eclipsing binary. The orbital periods of the planet candidates are 97.46 days (KIC 4552729) and 284.03 (KIC 10005758) days and the modeled planet radii are 5.3 and 3.8 R ⊕. The latter star has an additional known planet candidate with a radius of 5.05 R ⊕ and a period of 134.49 days, which was detected by the Kepler pipeline. The discovery of these candidates illustrates the value of massively distributed volunteer review of the Kepler database to recover candidates which were otherwise uncataloged.

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Ji Wang

California Institute of Technology

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