Now showing items 1-20 of 64

    • A 1.9 Earth Radius Rocky Planet and the Discovery of a Non-Transiting Planet in the Kepler-20 System 

      Buchhave, Lars A.; Dressing, Courtney D.; Dumusque, Xavier; Rice, Ken; Vanderburg, Andrew Michael; Mortier, Annelies; Lopez-Morales, Mercedes; Lopez, Eric; Lundkvist, Mia S.; Kjeldsen, Hans; Affer, Laura; Bonomo, Aldo S.; Charbonneau, David; Cameron, Andrew Collier; Cosentino, Rosario; Figueira, Pedro; Fiorenzano, Aldo F. M.; Harutyunyan, Avet; Haywood, Raphaelle D.; Johnson, John Asher; Latham, David Winslow; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Molinari, Emilio; Motalebi, Fatemeh; Nascimbeni, Valerio; Pepe, Francesco; Phillips, David F.; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Sasselov, Dimitar D.; Ségransan, Damien; Sozzetti, Alessandro; Udry, Stéphane; Watson, Chris (American Astronomical Society, 2016)
      Kepler-20 is a solar-type star (V = 12.5) hosting a compact system of five transiting planets, all packed within the orbital distance of Mercury in our own solar system. A transition from rocky to gaseous planets with a ...
    • The 4.5 µm full-orbit phase curve of the hot Jupiter HD 209458B 

      Zellem, Robert T.; Lewis, Nikole K.; Knutson, Heather A.; Griffith, Caitlin A.; Showman, Adam P.; Fortney, Jonathan J.; Cowan, Nicolas B.; Agol, Eric; Burrows, Adam; Charbonneau, David; Deming, Drake; Laughlin, Gregory; Langton, Jonathan (IOP Publishing, 2014)
      The hot Jupiter HD 209458b is particularly amenable to detailed study as it is among the brightest transiting exoplanet systems currently known (V-mag = 7.65; K-mag = 6.308) and has a large planet-to-star contrast ratio. ...
    • Absolute Properties of the Low-Mass Eclipsing Binary CM Draconis 

      Morales, Juan Carlos; Ribas, Ignasi; Jordi, Carme; Torres, Guillermo; Gallardo, Jose; Guinan, Edward F.; Charbonneau, David; Wolf, Marek; Latham, David W.; Anglada-Escude, Guillem; Bradstreet, David H.; Everett, Mark E.; O'Donovan, Francis T.; Mandushev, Georgi; Mathieu, Robert D. (Institute of Physics, 2009)
      Spectroscopic and eclipsing binary systems offer the best means for determining accurate physical properties of stars, including their masses and radii. The data available for low-mass stars have yielded firm evidence that ...
    • An Activity-Rotation Relationship and Kinematic Analysis of Nearby Mid-to-Late-Type M Dwarfs 

      West, Andrew A.; Weisenburger, Kolby L.; Irwin, Jonathan; Berta-Thompson, Zachory K.; Charbonneau, David; Dittmann, Jason Adam; Pineda, J. Sebastian (IOP Publishing, 2015)
      Using spectroscopic observations and photometric light curves of 238 nearby M dwarfs from the MEarth exoplanet transit survey, we examine the relationships between magnetic activity (quantified by Hα emission), rotation ...
    • Alien Maps of an Ocean-Bearing World 

      Cowan, Nicolas B.; Agol, Eric; Meadows, Victoria S.; Robinson, Tyler; Livengood, Timothy A.; Deming, Drake; Lisse, Carey M.; A'Hearn, Michael F.; Wellnitz, Dennis D.; Seager, Sara; Charbonneau, David (Institute of Physics, 2009)
      When Earth-mass extrasolar planets first become detectable, one challenge will be to determine which of these worlds harbor liquid water, a widely used criterion for habitability. Some of the first observations of these ...
    • An astro-comb calibrated solar telescope to search for the radial velocity signature of Venus 

      Phillips, David F.; Glenday, Alex; Dumusque, Xavier; Buchschacher, Nicolas; Cameron, Andrew Collier; Cecconi, Massimo; Charbonneau, David; Cosentino, Rosario; Ghedina, Adriano; Haywood, Raphaelle D.; Latham, David Winslow; Li, Chih-Hao; Lodi, Marcello; Lovis, Christophe; Molinari, Emilio; Pepe, Francesco; Sasselov, Dimitar D.; Szentgyorgyi, Andrew H.; Udry, Stephane; Walsworth, Ronald Lee (2016)
      We recently demonstrated sub-m/s sensitivity in measuring the radial velocity (RV) between the Earth and Sun using a simple solar telescope feeding the HARPS-N spectrograph at the Italian National Telescope, which is ...
    • Atmospheric Characterization of 5 Hot Jupiters with Wide Field Camera 3 on the Hubble Space Telescope 

      Ranjan, Sukrit; Charbonneau, David; Désert, Jean-Michel; Madhusudhan, Nikku; Deming, Drake; Wilkins, Ashlee; Mandell, Avi M. (IOP Publishing, 2014)
      We probe the structure and composition of the atmospheres of five hot Jupiter exoplanets using the Hubble Space Telescope Wide Field Camera 3 (WFC3) instrument. We use the G141 grism (1.1-1.7 μm) to study TrES-2b, TrES-4b, ...
    • Calibration of the MEarth Photometric System: Optical Magnitudes and Photometric Metallicity Estimates for 1802 Nearby M-dwarfs 

      Dittmann, Jason Adam; Irwin, Jonathan; Charbonneau, David; Newton, Elisabeth R (American Astronomical Society, 2016)
      The MEarth Project is a photometric survey systematically searching the smallest stars nearest to the Sun for transiting rocky planets. Since 2008, MEarth has taken approximately two million images of 1844 stars suspected ...
    • Characterization of the HD 17156 Planetary System 

      Barbieri, M.; Alonso, R.; Desidera, S.; Sozzetti, A.; Martinez Fiorenzano, A.F.; Almenara, J.M.; Cecconi, M.; Claudi, R.U.; Endl, M.; Granata, V.; Gratton, R.; Laughlin, G.; Loeillet, B.; Charbonneau, David (EDP Sciences, 2009)
      Aims. We present data to improve the known parameters of the HD 17156 system (peculiar due to the eccentricity and long orbital period of its transiting planet) and constrain the presence of stellar companions. Methods. ...
    • Characterizing K2 Planet Discoveries: A Super-Earth Transiting the Bright K Dwarf Hip 116454 

      Vanderburg, Andrew Michael; Montet, Benjamin T.; Johnson, John Asher; Buchhave, Lars A.; Zeng, Li; Pepe, Francesco; Cameron, Andrew Collier; Latham, David Winslow; Molinari, Emilio; Udry, Stéphane; Lovis, Christophe; Matthews, Jaymie M.; Cameron, Chris; Law, Nicholas; Bowler, Brendan P.; Angus, Ruth; Baranec, Christoph; Bieryla, Allyson; Boschin, Walter; Charbonneau, David; Cosentino, Rosario; Dumusque, Xavier; Figueira, Pedro; Guenther, David B.; Harutyunyan, Avet; Hellier, Coel; Kuschnig, Rainer; Lopez-Morales, Mercedes; Mayor, Michel; Micela, Giusi; Moffat, Anthony F. J.; Pedani, Marco; Phillips, David F.; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Riddle, Reed; Rowe, Jason F.; Rucinski, Slavek M.; Sasselov, Dimitar D.; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew H.; Watson, Chris; Weiss, Werner W. (IOP Publishing, 2015)
      We report the first planet discovery from the two-wheeled Kepler (K2) mission: HIP 116454 b. The host star HIP 116454 is a bright (V = 10.1, K = 8.0) K1 dwarf with high proper motion and a parallax-based distance of 55.2 ...
    • Constraints on Planet Occurrence Around Nearby Mid-to-Late M Dwarfs From the Mearth Project 

      Berta, Zachory; Irwin, Jonathan; Charbonneau, David (IOP Publishing, 2013)
      The MEarth Project is a ground-based photometric survey intended to find planets transiting the closest and smallest main-sequence stars. In its first four years, MEarth discovered one transiting exoplanet, the 2.7 R⊕ ...
    • A Disintegrating Minor Planet Transiting a White Dwarf 

      Vanderburg, Andrew Michael; Johnson, John Asher; Rappaport, Saul; Bieryla, Allyson; Irwin, Jonathan; Lewis, John Arban; Kipping, David; Brown, Warren R.; Dufour, Patrick; Ciardi, David R.; Angus, Ruth; Schaefer, Laura Kay; Latham, David Winslow; Charbonneau, David; Beichman, Charles; Eastman, Jason D.; McCrady, Nate; Wittenmyer, Robert A.; Wright, Jason T. (Springer Nature, 2015)
      White dwarfs are the end state of most stars, including the Sun, after they exhaust their nuclear fuel. Between 1/4 and 1/2 of white dwarfs have elements heavier than helium in their atmospheres1,2, even though these ...
    • Distances, Masses, Radii, and Metallicities of the Small Stars in the Solar Neighborhood 

      Dittmann, Jason (2016-05-16)
      Data from the NASA Kepler spacecraft indicate that small planets are common around the smallest main sequence stars (M dwarfs). Rocky planets transiting M dwarfs will be the best targets for atmospheric characterization ...
    • Dynamical Masses of Young M Dwarfs: Masses and Orbital Parameters of Gj 3305 Ab, the Wide Binary Companion to the Imaged Exoplanet Host 51 Eri 

      Montet, Benjamin T.; Bowler, Brendan P.; Shkolnik, Evgenya L.; Deck, Katherine M.; Wang, Ji; Horch, Elliott P.; Liu, Michael C.; Hillenbrand, Lynne A.; Kraus, Adam L.; Charbonneau, David (IOP Publishing, 2015)
      We combine new high resolution imaging and spectroscopy from Keck/NIRC2, Discovery Channel Telescope/DSSI, and Keck/HIRES with published astrometry and radial velocities to measure individual masses and orbital elements ...
    • An Earth-sized planet with an Earth-like density 

      Pepe, Francesco; Cameron, Andrew Collier; Latham, David Winslow; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S.; Buchhave, Lars A.; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F. M.; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaelle D.; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David F.; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar D.; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew H.; Watson, Christopher A. (Springer Nature, 2013)
      Recent analyses1–4 of data from the NASA Kepler spacecraft5 have established that planets with radii within 25 per cent of Earth’s (R⊕) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like ...
    • An Empirical Calibration to Estimate Cool Dwarf Fundamental Parameters From H-Band Spectra 

      Newton, Elisabeth R; Charbonneau, David; Irwin, Jonathan; Mann, Andrew W. (IOP Publishing, 2015)
      Interferometric radius measurements provide a direct probe of the fundamental parameters of M dwarfs. However, interferometry is within reach for only a limited sample of nearby, bright stars. We use interferometrically ...
    • The Evolution of Rotation and Magnetism in Small Stars Near the Sun 

      Newton, Elisabeth R. (2016-05-19)
      Despite the prevalence of M dwarfs, the smallest and most common type of main sequence star, their sizes, compositions, and ages are not well-constrained. Empirical determination of these properties is important for gaining ...
    • Exoplanet Characterization by Proxy: A Transiting 2.15 R⊕ Planet Near the Habitable Zone of the Late K Dwarf Kepler-61 

      Ballard, Sarah; Charbonneau, David; Fressin, Francois; Torres, Guillermo; Irwin, Jonathan; Desert, Jean-Michel; Newton, Elisabeth R; Mann, Andrew W.; Ciardi, David R.; Crepp, Justin R.; Henze, Christopher E.; Bryson, Stephen T.; Howell, Steven B.; Horch, Elliott P.; Everett, Mark E.; Shporer, Avi (IOP Publishing, 2013)
      We present the validation and characterization of Kepler-61b: a 2.15 R ⊕ planet orbiting near the inner edge of the habitable zone of a low-mass star. Our characterization of the host star Kepler-61 is based upon a comparison ...
    • The False Positive Rate of Kepler and the Occurrence of Planets 

      Fressin, François; Torres, Guillermo; Charbonneau, David; Bryson, Stephen T.; Christiansen, Jessie; Dressing, Courtney; Jenkins, Jon M.; Walkowicz, Lucianne M.; Batalha, Natalie M. (IOP Publishing, 2013)
      The Kepler mission is uniquely suited to study the frequencies of extrasolar planets. This goal requires knowledge of the incidence of false positives such as eclipsing binaries in the background of the targets, or physically ...
    • HARPS-N Observes the Sun as a Star 

      Dumusque, Xavier; Glenday, Alex; Phillips, David F.; Buchschacher, Nicolas; Cameron, Andrew Collier; Cecconi, Massimo; Charbonneau, David; Cosentino, Rosario; Ghedina, Adriano; Latham, David Winslow; Li, Chih-Hao; Lodi, Marcello; Lovis, Christophe; Molinari, Emilio; Pepe, Francesco; Udry, Stéphane; Sasselov, Dimitar D.; Szentgyorgyi, Andrew H.; Walsworth, Ronald Lee (IOP Publishing, 2015)
      Radial velocity (RV) perturbations induced by stellar surface inhomogeneities including spots, plages and granules currently limit the detection of Earth-twins using Doppler spectroscopy. Such stellar noise is poorly ...