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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

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Tennessee State University

2016

Planetary systems

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Three Temperate Neptunes Orbiting Nearby Stars, Benjamin J. Fulton, Andrew W. Howard, Lauren M. Weiss, Evan Sinukoff, Erik A. Petigura, Howard Isaacson, Lea A. Hirsch, Geoffrey W. Marcy, Gregory W. Henry, Samuel K. Grunblatt, Daniel Huber, Kaspar Von Braun, Tabetha S. Boyajian, Stephen R. Kane, Justin Wittrock, Elliott P. Horch, David R. Ciardi, Steve B. Howell, Jason T. Wright, Eric B. Ford Oct 2016

Three Temperate Neptunes Orbiting Nearby Stars, Benjamin J. Fulton, Andrew W. Howard, Lauren M. Weiss, Evan Sinukoff, Erik A. Petigura, Howard Isaacson, Lea A. Hirsch, Geoffrey W. Marcy, Gregory W. Henry, Samuel K. Grunblatt, Daniel Huber, Kaspar Von Braun, Tabetha S. Boyajian, Stephen R. Kane, Justin Wittrock, Elliott P. Horch, David R. Ciardi, Steve B. Howell, Jason T. Wright, Eric B. Ford

Information Systems and Engineering Management Research Publications

We present the discovery of three modestly irradiated, roughly Neptune-mass planets orbiting three nearby Solar-type stars. HD 42618 b has a minimum mass of 15.4 ± 2.4 ${M}_{\oplus }$, a semimajor axis of 0.55 au, an equilibrium temperature of 337 K, and is the first planet discovered to orbit the solar analogue host star, HD 42618. We also discover new planets orbiting the known exoplanet host stars HD 164922 and HD 143761 (ρ CrB). The new planet orbiting HD 164922 has a minimum mass of 12.9 ± 1.6 ${M}_{\oplus }$ and orbits interior to the previously known Jovian mass planet …


Very Low-Mass Stellar And Substellar Companions To Solar-Like Stars From Marvels. Vi. A Giant Planet And A Brown Dwarf Candidate In A Close Binary System Hd 87646, Bo Ma, Jian Ge, Alex Wolszczan, Matthew W. Muterspaugh, Brian Lee, Gregory W. Henry, Donald P. Schneider, Eduardo L. Martín, Andrzej Niedzielski, Jiwei Xie, Scott W. Fleming, Neil Thomas, Michael Williamson, Zhaohuan Zhu, Eric Agol, Dmitry Bizyaev, Luiz Nicolaci Da Costa, Peng Jiang, Aldo Fabricio Martinez Fiorenzano, Jonay I. González Hernández, Pengcheng Guo, Nolan Grieves, Rui Li, Jane Liu, Suvrath Mahadevan, Tsevi Mazeh, Duy Cuong Nguyen, Martin Paegert, Sirinrat Sithajan, Keivan Stassun, Sivarani Thirupathi, Julian C. Van Eyken, Xiaoke Wan, Ji Wang, John P. Wisniewski, Bo Zhao, Shay Zucker Oct 2016

Very Low-Mass Stellar And Substellar Companions To Solar-Like Stars From Marvels. Vi. A Giant Planet And A Brown Dwarf Candidate In A Close Binary System Hd 87646, Bo Ma, Jian Ge, Alex Wolszczan, Matthew W. Muterspaugh, Brian Lee, Gregory W. Henry, Donald P. Schneider, Eduardo L. Martín, Andrzej Niedzielski, Jiwei Xie, Scott W. Fleming, Neil Thomas, Michael Williamson, Zhaohuan Zhu, Eric Agol, Dmitry Bizyaev, Luiz Nicolaci Da Costa, Peng Jiang, Aldo Fabricio Martinez Fiorenzano, Jonay I. González Hernández, Pengcheng Guo, Nolan Grieves, Rui Li, Jane Liu, Suvrath Mahadevan, Tsevi Mazeh, Duy Cuong Nguyen, Martin Paegert, Sirinrat Sithajan, Keivan Stassun, Sivarani Thirupathi, Julian C. Van Eyken, Xiaoke Wan, Ji Wang, John P. Wisniewski, Bo Zhao, Shay Zucker

Information Systems and Engineering Management Research Publications

We report the detections of a giant planet (MARVELS-7b) and a brown dwarf (BD) candidate (MARVELS-7c) around the primary star in the close binary system, HD 87646. To the best of our knowledge, it is the first close binary system with more than one substellar circumprimary companion that has been discovered. The detection of this giant planet was accomplished using the first multi-object Doppler instrument (KeckET) at the Sloan Digital Sky Survey (SDSS) telescope. Subsequent radial velocity observations using the Exoplanet Tracker at the Kitt Peak National Observatory, the High Resolution Spectrograph at the Hobby Eberley telescope, the "Classic" spectrograph …


Hst Hot-Jupiter Transmission Spectral Survey: Clear Skies For Cool Saturn Wasp-39b, Patrick D. Fischer, Heather Knutson, David K. Sing, Gregory W. Henry, Michael H. Williamson, Jonathan J. Fortney, Adam S. Burrows, Tiffany Kataria, Nikolay Nikolov, Adam P. Showman, Gilda E. Ballester, Jean-Michel Désert, Suzanne Aigrain, Drake Deming, Alain Lecavelier Des Etangs, Alfred Vidal-Madjar Aug 2016

Hst Hot-Jupiter Transmission Spectral Survey: Clear Skies For Cool Saturn Wasp-39b, Patrick D. Fischer, Heather Knutson, David K. Sing, Gregory W. Henry, Michael H. Williamson, Jonathan J. Fortney, Adam S. Burrows, Tiffany Kataria, Nikolay Nikolov, Adam P. Showman, Gilda E. Ballester, Jean-Michel Désert, Suzanne Aigrain, Drake Deming, Alain Lecavelier Des Etangs, Alfred Vidal-Madjar

Information Systems and Engineering Management Research Publications

We present the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) optical transmission spectroscopy of the cool Saturn-mass exoplanet WASP-39b from 0.29-1.025 μm, along with complementary transit observations from Spitzer IRAC at 3.6 and 4.5 μm. The low density and large atmospheric pressure scale height of WASP-39b make it particularly amenable to atmospheric characterization using this technique. We detect a Rayleigh scattering slope as well as sodium and potassium absorption features; this is the first exoplanet in which both alkali features are clearly detected with the extended wings predicted by cloud-free atmosphere models. The full transmission spectrum is well …


A Combined Spectroscopic And Photometric Stellar Activity Study Of Epsilon Eridani, Matthew J. Giguere, Debra A. Fischer, Cyril X. Y. Zhang, Jaymie M. Matthews, Chris Cameron, Gregory W. Henry Jun 2016

A Combined Spectroscopic And Photometric Stellar Activity Study Of Epsilon Eridani, Matthew J. Giguere, Debra A. Fischer, Cyril X. Y. Zhang, Jaymie M. Matthews, Chris Cameron, Gregory W. Henry

Information Systems and Engineering Management Research Publications

We present simultaneous ground-based radial velocity (RV) measurements and space-based photometric measurements of the young and active K dwarf Epsilon Eridani. These measurements provide a data set for exploring methods of identifying and ultimately distinguishing stellar photospheric velocities from Keplerian motion. We compare three methods we have used in exploring this data set: Dalmatian, an MCMC spot modeling code that fits photometric and RV measurements simultaneously; the FF' method, which uses photometric measurements to predict the stellar activity signal in simultaneous RV measurements; and Hα analysis. We show that our Hα measurements are strongly correlated with the Microvariability and Oscillations …


Evidence For Reflected Light From The Most Eccentric Exoplanet Known, Stephen R. Kane, Robert A. Wittenmyer, Natalie R. Hinkel, Arpita Roy, Suvrath Mahadevan, Diana Dragomir, Jaymie M. Matthews, Gregory W. Henry, Abhijit Chakraborty, Tabetha S. Boyajian Apr 2016

Evidence For Reflected Light From The Most Eccentric Exoplanet Known, Stephen R. Kane, Robert A. Wittenmyer, Natalie R. Hinkel, Arpita Roy, Suvrath Mahadevan, Diana Dragomir, Jaymie M. Matthews, Gregory W. Henry, Abhijit Chakraborty, Tabetha S. Boyajian

Information Systems and Engineering Management Research Publications

Planets in highly eccentric orbits form a class of objects not seen within our solar system. The most extreme case known among these objects is the planet orbiting HD 20782, with an orbital period of 597 days and an eccentricity of 0.96. Here we present new data and analysis for this system as part of the Transit Ephemeris Refinement and Monitoring Survey. We obtained CHIRON spectra to perform an independent estimation of the fundamental stellar parameters. New radial velocities from Anglo-Australian Telescope and PARAS observations during periastron passage greatly improve our knowledge of the eccentric nature of the orbit. The …


Stellar Activity And Exclusion Of The Outer Planet In The Hd 99492 System, Stephen R. Kane, Badrinath Thirumalachari, Gregory W. Henry, Natalie R. Hinkel, Eric L. N. Jensen, Tabetha S. Boyajian, Debra A. Fischer, Andrew W. Howard, Howard Isaacson, Jason T. Wright Mar 2016

Stellar Activity And Exclusion Of The Outer Planet In The Hd 99492 System, Stephen R. Kane, Badrinath Thirumalachari, Gregory W. Henry, Natalie R. Hinkel, Eric L. N. Jensen, Tabetha S. Boyajian, Debra A. Fischer, Andrew W. Howard, Howard Isaacson, Jason T. Wright

Information Systems and Engineering Management Research Publications

A historical problem for indirect exoplanet detection has been contending with the intrinsic variability of the host star. If the variability is periodic, it can easily mimic various exoplanet signatures, such as radial velocity (RV) variations that originate with the stellar surface rather than the presence of a planet. Here we present an update for the HD 99492 planetary system, using new RV and photometric measurements from the Transit Ephemeris Refinement and Monitoring Survey. Our extended time series and subsequent analyses of the Ca ii H&K emission lines show that the host star has an activity cycle of ∼13 years. …