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Full-Text Articles in Astrophysics and Astronomy

The Hst Pancet Program: Hints Of Na I And Evidence Of A Cloudy Atmosphere For The Inflated Hot Jupiter Wasp-52b, Munazza K. Alam, Nikolay Nikolov, Mercedes López-Morales, David K. Sing, Jayesh M. Goyal, Gregory W. Henry, Jorge Sanz-Forcada, Michael H. Williamson, Thomas M. Evans, Hannah R. Wakeford, Giovanni Bruno, Gilda E. Ballester, Kevin B. Stevenson, Nikole K. Lewis, Joanna K. Barstow, Vincent Bourrier, Lars A. Buchhave, David Ehrenreich, Antonio García Muñoz Dec 2018

The Hst Pancet Program: Hints Of Na I And Evidence Of A Cloudy Atmosphere For The Inflated Hot Jupiter Wasp-52b, Munazza K. Alam, Nikolay Nikolov, Mercedes López-Morales, David K. Sing, Jayesh M. Goyal, Gregory W. Henry, Jorge Sanz-Forcada, Michael H. Williamson, Thomas M. Evans, Hannah R. Wakeford, Giovanni Bruno, Gilda E. Ballester, Kevin B. Stevenson, Nikole K. Lewis, Joanna K. Barstow, Vincent Bourrier, Lars A. Buchhave, David Ehrenreich, Antonio García Muñoz

Information Systems and Engineering Management Research Publications

We present an optical to near-infrared transmission spectrum of the inflated hot Jupiter WASP-52b using three transit observations from the Space Telescope Imaging Spectrograph mounted on the Hubble Space Telescope, combined with Spitzer/Infrared Array Camera photometry at 3.6 and 4.5 μm. Since WASP-52 is a moderately active (log(Lx/Lbol) = −4.7) star, we correct the transit light curves for the effect of stellar activity using ground-based photometric monitoring data from the All-sky Automated Survey for Supernovae (ASAS-SN) and Tennessee State University's Automatic Imaging Telescope. We bin the data in 38 spectrophotometric light curves from 0.29 to 4.5 μm and measure the …


Covariations Of Chromospheric And Photometric Variability Of The Young Sun Analogue Hd 30495: Evidence For And Interpretation Of Mid-Term Periodicities, Willie Soon, Victor M. Velasco Herrera, Rodolfo G. Cionco, S. Qiu, Sallie Baliunas, Ricky Egeland, Gregory W. Henry, Ivanka Charvátová Dec 2018

Covariations Of Chromospheric And Photometric Variability Of The Young Sun Analogue Hd 30495: Evidence For And Interpretation Of Mid-Term Periodicities, Willie Soon, Victor M. Velasco Herrera, Rodolfo G. Cionco, S. Qiu, Sallie Baliunas, Ricky Egeland, Gregory W. Henry, Ivanka Charvátová

Information Systems and Engineering Management Research Publications

This study reports the synchronization between the chromospheric and photometric variability at time-scale of about 1.6–1.8 yr as observed for the young, rapidly rotating solar analogue HD 30495. In addition, HD 30495 may be presenting evidence of surface differential rotation at time-scales of about 11 d and 21 d, as well as the sunspot-like decadal cycles at 11–12 yr or so. We apply a new gapped wavelet method of time–frequency analysis for studying the variability in a new composite of the chromospheric S-index (1967–2018) and the longest photometric Δ(b + y)/2 index (1993–2018). We discuss and interpret our results in …


Detection Of Helium In The Atmosphere Of The Exo-Neptune Hat-P-11b, Megan Mansfield, Jacob L. Bean, Antonija Oklopčić, Laura Kreidberg, Jean-Michel Désert, Eliza M. R. Kempton, Michael R. Line, Jonathan J. Fortney, Gregory W. Henry, Matthias Mallonn, Kevin B. Stevenson, Diana Dragomir, Romain Allart, Vincent Bourrier Nov 2018

Detection Of Helium In The Atmosphere Of The Exo-Neptune Hat-P-11b, Megan Mansfield, Jacob L. Bean, Antonija Oklopčić, Laura Kreidberg, Jean-Michel Désert, Eliza M. R. Kempton, Michael R. Line, Jonathan J. Fortney, Gregory W. Henry, Matthias Mallonn, Kevin B. Stevenson, Diana Dragomir, Romain Allart, Vincent Bourrier

Information Systems and Engineering Management Research Publications

The helium absorption triplet at a wavelength of 10833 Å has been proposed as a way to probe the escaping atmospheres of exoplanets. Recently this feature was detected for the first time using Hubble Space Telescope (HST) WFC3 observations of the hot Jupiter WASP-107b. We use similar HST/WFC3 observations to detect helium in the atmosphere of the hot Neptune HAT-P-11b at the 4σ confidence level. We compare our observations to a grid of 1D models of hydrodynamic escape to constrain the thermospheric temperatures and mass loss rate. We find that our data are best fit by models with high mass …


An Optical Transmission Spectrum For The Ultra-Hot Jupiter Wasp-121b Measured With The Hubble Space Telescope, Thomas M. Evans, David K. Sing, Jayesh M. Goyal, Nikolay Nikolov, Mark S. Marley, Kevin Zahnle, Gregory W. Henry, Joanna K. Barstow, Munazza K. Alam, Jorge Sanz-Forcada, Tiffany Kataria, Nikole K. Lewis, Panayotis Lavvas, Gilda E. Ballester, Lotfi Ben-Jaffel, Sarah D. Blumenthal, Vincent Bourrier, Benjamin Drummond, Antonio García Muñoz, Mercedes López-Morales, Pascal Tremblin, David Ehrenreich, Hannah R. Wakeford, Lars A. Buchhave, Alain Lecavelier Des Etangs, Éric Hébrard, Michael H. Williamson Nov 2018

An Optical Transmission Spectrum For The Ultra-Hot Jupiter Wasp-121b Measured With The Hubble Space Telescope, Thomas M. Evans, David K. Sing, Jayesh M. Goyal, Nikolay Nikolov, Mark S. Marley, Kevin Zahnle, Gregory W. Henry, Joanna K. Barstow, Munazza K. Alam, Jorge Sanz-Forcada, Tiffany Kataria, Nikole K. Lewis, Panayotis Lavvas, Gilda E. Ballester, Lotfi Ben-Jaffel, Sarah D. Blumenthal, Vincent Bourrier, Benjamin Drummond, Antonio García Muñoz, Mercedes López-Morales, Pascal Tremblin, David Ehrenreich, Hannah R. Wakeford, Lars A. Buchhave, Alain Lecavelier Des Etangs, Éric Hébrard, Michael H. Williamson

Information Systems and Engineering Management Research Publications

We present an atmospheric transmission spectrum for the ultra-hot Jupiter WASP-121b, measured using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. Across the 0.47–1 wavelength range, the data imply an atmospheric opacity comparable to—and in some spectroscopic channels exceeding—that previously measured at near-infrared wavelengths (1.15–1.65 ). Wavelength-dependent variations in the opacity rule out a gray cloud deck at a confidence level of 3.7σ and may instead be explained by VO spectral bands. We find a cloud-free model assuming chemical equilibrium for a temperature of 1500 K and a metal enrichment of 10–30× solar matches …


The 55 Cancri System Reassessed, Vincent Bourrier, Xavier Dumusque, Caroline Dorn, Gregory W. Henry, Nicola Astudillo-Defru, Javiera Rey, Björn Benneke, Guillaume Hébrard, Christophe Lovis, Brice-Olivier Demory, C. Moutou, David Ehrenreich Oct 2018

The 55 Cancri System Reassessed, Vincent Bourrier, Xavier Dumusque, Caroline Dorn, Gregory W. Henry, Nicola Astudillo-Defru, Javiera Rey, Björn Benneke, Guillaume Hébrard, Christophe Lovis, Brice-Olivier Demory, C. Moutou, David Ehrenreich

Information Systems and Engineering Management Research Publications

Orbiting a bright, nearby star the 55 Cnc system offers a rare opportunity to study a multiplanet system that has a wide range of planetary masses and orbital distances. Using two decades of photometry and spectroscopy data, we have measured the rotation of the host star and its solar-like magnetic cycle. Accounting for this cycle in our velocimetric analysis of the system allows us to revise the properties of the outermost giant planet and its four planetary companions. The innermost planet 55 Cnc e is an unusually close-in super-Earth, whose transits have allowed for detailed follow-up studies. Recent observations favor …


Separated Fringe Packet Observations With The Chara Array. Iii. The Very High-Eccentricity Binary Hr 7345, Chris D. Farrington, Francis C. Fekel, Gail Schaefer, Theo A. Ten Brummelaar Sep 2018

Separated Fringe Packet Observations With The Chara Array. Iii. The Very High-Eccentricity Binary Hr 7345, Chris D. Farrington, Francis C. Fekel, Gail Schaefer, Theo A. Ten Brummelaar

Information Systems and Engineering Management Research Publications

After an 11-year observing campaign, we present the combined visual–spectroscopic orbit of the formerly unremarkable bright star HR 7345 (HD 181655, HIP 94981, GJ 754.2). Using the Separated Fringe Packet method with the CHARA Array, we were able to determine a difficult-to-complete orbital period of 331.609 ± 0.004 days. The 11-month period causes the system to be hidden from interferometric view behind the Sun for three years at a time. Due to the high-eccentricity orbit of about 90% of a year, after 2018 January the periastron phase will not be observable again until late 2021. Hindered by its extremely high …


Spectroscopic Orbits For Late-Type Stars. Ii, Francis C. Fekel, Daryl W. Willmarth, Helmut A. Abt, Dimitri Pourbaix Aug 2018

Spectroscopic Orbits For Late-Type Stars. Ii, Francis C. Fekel, Daryl W. Willmarth, Helmut A. Abt, Dimitri Pourbaix

Information Systems and Engineering Management Research Publications

We have determined spectroscopic orbital elements for 13 systems—10 single-lined binaries and three double-lined binaries. For the three binaries with previously published spectroscopic orbits, we have computed improved or comparable elements. While two systems have relatively short periods between 10 and 19 days, the remaining systems have much longer periods ranging from 604 to 9669 days. One of the single-lined systems, HD 142640, shows both short-period and long-period velocity variations and so is triple. For three systems—HD 59380, HD 160933, and HD 161163—we have combined our spectroscopic results with Hipparcos astrometric observations to obtain astrometric orbits. For HD 14802 we …


The First Super-Earth Detection From The High Cadence And High Radial Velocity Precision Dharma Planet Survey, Bo Ma, Jian Ge, Matthew Muterspaugh, Michael A. Singer, Gregory W. Henry, Jonay I. González Hernández, Sirinrat Sithajan, Sarik Jeram, Michael H. Williamson, Keivan Stassun, Benjamin Kimock, Frank Varosi, Sidney Schofield, Jian Liu, Scott Powell, Anthony Cassette, Hali Jakeman, Louis Avner, Nolan Grieves, Rory Barnes, Bo Zhao, Sankalp Gilda, Jim Grantham, Greg Stafford, David Savage, Steve Bland, Brent Ealey Jul 2018

The First Super-Earth Detection From The High Cadence And High Radial Velocity Precision Dharma Planet Survey, Bo Ma, Jian Ge, Matthew Muterspaugh, Michael A. Singer, Gregory W. Henry, Jonay I. González Hernández, Sirinrat Sithajan, Sarik Jeram, Michael H. Williamson, Keivan Stassun, Benjamin Kimock, Frank Varosi, Sidney Schofield, Jian Liu, Scott Powell, Anthony Cassette, Hali Jakeman, Louis Avner, Nolan Grieves, Rory Barnes, Bo Zhao, Sankalp Gilda, Jim Grantham, Greg Stafford, David Savage, Steve Bland, Brent Ealey

Information Systems and Engineering Management Research Publications

The Dharma Planet Survey (DPS) aims to monitor about 150 nearby very bright FGKM dwarfs (within 50 pc) during 2016–2020 for low-mass planet detection and characterization using the TOU very high resolution optical spectrograph (⁠R≈100000⁠, 380–900 nm). TOU was initially mounted to the 2-m Automatic Spectroscopic Telescope at Fairborn Observatory in 2013–2015 to conduct a pilot survey, then moved to the dedicated 50-inch automatic telescope on Mt. Lemmon in 2016 to launch the survey. Here, we report the first planet detection from DPS, a super-Earth candidate orbiting a bright K dwarf star, HD 26965. It is the second brightest star …


Global Climate And Atmospheric Composition Of The Ultra-Hot Jupiter Wasp-103b From Hst And Spitzer Phase Curve Observations, Laura Kreidberg, Michael R. Line, Vivien Parmentier, Kevin B. Stevenson, Tom Louden, Mickäel Bonnefoy, Jacqueline K. Faherty, Gregory W. Henry, Michael H. Williamson, Keivan Stassun, Thomas G. Beatty, Jacob L. Bean, Jonathan J. Fortney, Adam P. Showman, Jean-Michel Désert, Jacob Arcangeli Jun 2018

Global Climate And Atmospheric Composition Of The Ultra-Hot Jupiter Wasp-103b From Hst And Spitzer Phase Curve Observations, Laura Kreidberg, Michael R. Line, Vivien Parmentier, Kevin B. Stevenson, Tom Louden, Mickäel Bonnefoy, Jacqueline K. Faherty, Gregory W. Henry, Michael H. Williamson, Keivan Stassun, Thomas G. Beatty, Jacob L. Bean, Jonathan J. Fortney, Adam P. Showman, Jean-Michel Désert, Jacob Arcangeli

Information Systems and Engineering Management Research Publications

We present thermal phase curve measurements for the hot Jupiter WASP-103b observed with Hubble/WFC3 and Spitzer/IRAC. The phase curves have large amplitudes and negligible hotspot offsets, indicative of poor heat redistribution to the nightside. We fit the phase variation with a range of climate maps and find that a spherical harmonics model generally provides the best fit. The phase-resolved spectra are consistent with blackbodies in the WFC3 bandpass, with brightness temperatures ranging from 1880 ± 40 K on the nightside to 2930 ± 40 K on the dayside. The dayside spectrum has a significantly higher brightness temperature in the Spitzer …


Helium In The Eroding Atmosphere Of An Exoplanet, Jess J. Spake, David K. Sing, Tom M. Evans, Antonija Oklopčić, Vincent Bourrier, Laura Kreidberg, Benjamin V. Rackham, Jonathan Irwin, David Ehrenreich, Aurélien Wyttenbach, Hannah R. Wakeford, Yifan Zhou, Katy L. Chubb, Nikolay Nikolov, Jayesh M. Goyal, Gregory W. Henry, Michael H. Williamson, Sarah Blumenthal, David R. Anderson, Coel Hellier, David Charbonneau, Stephane Udry, Nikku Madhusudhan May 2018

Helium In The Eroding Atmosphere Of An Exoplanet, Jess J. Spake, David K. Sing, Tom M. Evans, Antonija Oklopčić, Vincent Bourrier, Laura Kreidberg, Benjamin V. Rackham, Jonathan Irwin, David Ehrenreich, Aurélien Wyttenbach, Hannah R. Wakeford, Yifan Zhou, Katy L. Chubb, Nikolay Nikolov, Jayesh M. Goyal, Gregory W. Henry, Michael H. Williamson, Sarah Blumenthal, David R. Anderson, Coel Hellier, David Charbonneau, Stephane Udry, Nikku Madhusudhan

Information Systems and Engineering Management Research Publications

Helium is the second-most abundant element in the Universe after hydrogen and is one of the main constituents of gas-giant planets in our Solar System. Early theoretical models predicted helium to be among the most readily detectable species in the atmospheres of exoplanets, especially in extended and escaping atmospheres1. Searches for helium, however, have hitherto been unsuccessful2. Here we report observations of helium on an exoplanet, at a confidence level of 4.5 standard deviations. We measured the near-infrared transmission spectrum of the warm gas giant3 WASP-107b and identified the narrow absorption feature of excited metastable helium at 10,833 angstroms. The …


Patterns Of Variation For The Sun And Sun-Like Stars, Richard R. Radick, G. Wesley Lockwood, Gregory W. Henry, Jeffrey C. Hall, Alexei A. Pevtsov Mar 2018

Patterns Of Variation For The Sun And Sun-Like Stars, Richard R. Radick, G. Wesley Lockwood, Gregory W. Henry, Jeffrey C. Hall, Alexei A. Pevtsov

Information Systems and Engineering Management Research Publications

We compare patterns of variation for the Sun and 72 Sun-like stars by combining total and spectral solar irradiance measurements between 2003 and 2017 from the SORCE satellite, Strömgren b, y stellar photometry between 1993 and 2017 from Fairborn Observatory, and solar and stellar chromospheric Ca ii H+K emission observations between 1992 and 2016 from Lowell Observatory. The new data and their analysis strengthen the relationships found previously between chromospheric and brightness variability on the decadal timescale of the solar activity cycle. Both chromospheric H+K and photometric b, y variability among Sun-like stars are related to average chromospheric activity by …


Precision Orbit Of Δ Delphini And Prospects For Astrometric Detection Of Exoplanets, Tyler Gardner, John D. Monnier, Francis C. Fekel, Michael H. Williamson, Douglas K. Duncan, Timothy R. White, Michael Ireland, Fred C. Adams, Travis Barman, Fabien Baron, Theo A. Ten Brummelaar, Xiao Che, Daniel Huber, Stefan Kraus, Rachael M. Roettenbacher, Gail Schaefer, Judit Sturmann, Laszlo Sturmann, Samuel J. Swihart, Ming Zhao Feb 2018

Precision Orbit Of Δ Delphini And Prospects For Astrometric Detection Of Exoplanets, Tyler Gardner, John D. Monnier, Francis C. Fekel, Michael H. Williamson, Douglas K. Duncan, Timothy R. White, Michael Ireland, Fred C. Adams, Travis Barman, Fabien Baron, Theo A. Ten Brummelaar, Xiao Che, Daniel Huber, Stefan Kraus, Rachael M. Roettenbacher, Gail Schaefer, Judit Sturmann, Laszlo Sturmann, Samuel J. Swihart, Ming Zhao

Information Systems and Engineering Management Research Publications

Combining visual and spectroscopic orbits of binary stars leads to a determination of the full 3D orbit, individual masses, and distance to the system. We present a full analysis of the evolved binary system δ Delphini using astrometric data from the MIRC and PAVO instruments on the CHARA long-baseline interferometer, 97 new spectra from the Fairborn Observatory, and 87 unpublished spectra from the Lick Observatory. We determine the full set of orbital elements for δ Del, along with masses of 1.78 ± 0.07 M⊙ and 1.62 ± 0.07 M⊙ for each component, and a distance of 63.61 ± 0.89 pc. …


The First Post-Kepler Brightness Dips Of Kic 8462852, Tabetha S. Boyajian, Roi Alonso, Alex Ammerman, David Armstrong, Andrés Asensio Ramos, K. Barkaoui, Thomas G. Beatty, Zouhair Benkhaldoun, Paul Benni, Rory O. Bentley, Andrei Berdyugin, Svetlana Berdyugina, Serge Bergeron, Allyson Bieryla, Michaela G. Blain, Alicia Capetillo Blanco, Eva H. L. Bodman, Anne Boucher, Mark Bradley, Stephen M. Brincat, Thomas G. Brink, John Briol, David J. A. Brown, Jan Budaj, Artem Burdanov, Bryson Cale, Miguel Aznar Carbo, R. Castillo García, Wendy J. Clark, Geoffrey C. Clayton, James L. Clem, Phillip H. Coker, Evan M. Cook, Chris M. Copperwheat, Jason L. Curtis, Roc M. Cutri, Borbála Cseh, C. H. Cynamon, Alex J. Daniels, James R. A. Davenport, Hans J. Deeg, Roberto De Lorenzo, Thomas De Jaeger, Jean-Bruno Desrosiers, John Dolan, D. J. Dowhos, Franky Dubois, Russell Durkee, Shawn Dvorak, Lynn Easley, Nick Edwards, Tyler G. Ellis, Emery Erdelyi, Steve Ertel, Rafael G. Farfán, Jay Farihi, Alexei V. Filippenko, Emma Foxell, Davide Gandolfi, Faustino Garcia, Frank Giddens, Michaël Gillon, Juan-Luis González-Carballo, Carlos González-Fernández, Jonay I. González Hernández, Keith A. Graham, Kenton A. Greene, Joao Gregorio, Na'ama Hallakoun, Ottó Hanyecz, Gerry R. Harp, Gregory W. Henry, E. Herrero, Caleb F. Hildbold, D. Hinzel, Gonzalo Holgado, Bernadett Ignácz, Ilya Ilyin, Valentin D. Ivanov, ‪Emmanuel Jehin, Helen E. Jermak, Steve Johnston, Stella Kafka, Csilla Kalup, Emmanuel Kardasis, Shai Kaspi, Grant M. Kennedy, F. Kiefer, Collin L. Kielty, Dennis Kessler, Harri Kiiskinen, Thomas L. Killestein, Ronald A. King, Vladimír Kollar, Heidi Korhonen, C. Kotnik, Réka Könyves-Tóth, Levente Kriskovics, Nathan Krumm, Vadim Krushinsky, E. Kundra, Francois-Rene Lachapelle, Daryll Lacourse, P. Lake, Kristine Lam, Gavin P. Lamb, Dave Lane, Marie Wingyee Lau, Pablo Lewin, Chris Lintott, Carey Lisse, Ludwig Logie, Nicolas Longeard, M. Lopez Villanueva, E. Whit Ludington, Amy Mainzer, Lison Malo, Chris Maloney, Andrew Mann, A. Mantero, Massimo Marengo, Jon Marchant, María Jesús Martínez González, Joseph R. Masiero, Jon C. Mauerhan, James Mccormac, Aaron Mcneely, Huan Y. A. Meng, Mike Miller, Lawrence A. Molnar, Juan Carlos Morales, Brett M. Morris, Matthew W. Muterspaugh, David Nespra, Carrie R. Nugent, Katherine M. Nugent, A. Odasso, Derek O'Keeffe, Arto Oksanen, John M. O'Meara, András Ordasi, Hugh Osborn, John J. Ott, J. R. Parks, Diego Rodriguez Perez, Vance Petriew, Roger Pickard, András Pál, Peter Plavchan, Don Pollacco, Francisco Pozo-Nuñez, Francisco J. Pozuelos, Steve Rau, Seth Redfield, Howard Relles, Ignasi Ribas, Jon Richards, Joonas L. O. Saario, Emily J. Safron, J. Martin Sallai, Krisztián Sárneczky, Bradley E. Schaefer, Clea F. Schumer, Madison Schwartzendruber, Michael H. Siegel, Andrew P. V. Siemion, Brooke D. Simmons, Joshua D. Simon, Sergio Simón-Díaz, Michael L. Sitko, Hector Socas-Navarro, Ádám Sódor, Donn Starkey, Iain A. Steele, Geoff Stone, Klaus G. Strassmeier, Rachel A. Street, Tricia Sullivan, Jari Suomela, Jon J. Swift, Gyula M. Szabó, Róbert Szabó, Róbert Szakáts, Tamás Szalai, Angelle M. Tanner, Borja Toledo-Padrón, Tamás Tordai, Amaury H. M. J. Triaud, Jake D. Turner, Joseph H. Ulowetz, Marian Urbanik, Siegfried Vanaverbeke, Andrew Vanderburg, Krisztián Vida, Brad P. Vietje, József Vinkó, Kaspar Von Braun, Elizabeth O. Waagen, Dan Walsh, Christopher A. Watson, R. C. Weir, Klaus Wenzel, Carlos Westendorp, Michael W. Williamson, Jason T. Wright, Mark C. Wyatt, Weikang Zheng, Gabriella Zsidi Jan 2018

The First Post-Kepler Brightness Dips Of Kic 8462852, Tabetha S. Boyajian, Roi Alonso, Alex Ammerman, David Armstrong, Andrés Asensio Ramos, K. Barkaoui, Thomas G. Beatty, Zouhair Benkhaldoun, Paul Benni, Rory O. Bentley, Andrei Berdyugin, Svetlana Berdyugina, Serge Bergeron, Allyson Bieryla, Michaela G. Blain, Alicia Capetillo Blanco, Eva H. L. Bodman, Anne Boucher, Mark Bradley, Stephen M. Brincat, Thomas G. Brink, John Briol, David J. A. Brown, Jan Budaj, Artem Burdanov, Bryson Cale, Miguel Aznar Carbo, R. Castillo García, Wendy J. Clark, Geoffrey C. Clayton, James L. Clem, Phillip H. Coker, Evan M. Cook, Chris M. Copperwheat, Jason L. Curtis, Roc M. Cutri, Borbála Cseh, C. H. Cynamon, Alex J. Daniels, James R. A. Davenport, Hans J. Deeg, Roberto De Lorenzo, Thomas De Jaeger, Jean-Bruno Desrosiers, John Dolan, D. J. Dowhos, Franky Dubois, Russell Durkee, Shawn Dvorak, Lynn Easley, Nick Edwards, Tyler G. Ellis, Emery Erdelyi, Steve Ertel, Rafael G. Farfán, Jay Farihi, Alexei V. Filippenko, Emma Foxell, Davide Gandolfi, Faustino Garcia, Frank Giddens, Michaël Gillon, Juan-Luis González-Carballo, Carlos González-Fernández, Jonay I. González Hernández, Keith A. Graham, Kenton A. Greene, Joao Gregorio, Na'ama Hallakoun, Ottó Hanyecz, Gerry R. Harp, Gregory W. Henry, E. Herrero, Caleb F. Hildbold, D. Hinzel, Gonzalo Holgado, Bernadett Ignácz, Ilya Ilyin, Valentin D. Ivanov, ‪Emmanuel Jehin, Helen E. Jermak, Steve Johnston, Stella Kafka, Csilla Kalup, Emmanuel Kardasis, Shai Kaspi, Grant M. Kennedy, F. Kiefer, Collin L. Kielty, Dennis Kessler, Harri Kiiskinen, Thomas L. Killestein, Ronald A. King, Vladimír Kollar, Heidi Korhonen, C. Kotnik, Réka Könyves-Tóth, Levente Kriskovics, Nathan Krumm, Vadim Krushinsky, E. Kundra, Francois-Rene Lachapelle, Daryll Lacourse, P. Lake, Kristine Lam, Gavin P. Lamb, Dave Lane, Marie Wingyee Lau, Pablo Lewin, Chris Lintott, Carey Lisse, Ludwig Logie, Nicolas Longeard, M. Lopez Villanueva, E. Whit Ludington, Amy Mainzer, Lison Malo, Chris Maloney, Andrew Mann, A. Mantero, Massimo Marengo, Jon Marchant, María Jesús Martínez González, Joseph R. Masiero, Jon C. Mauerhan, James Mccormac, Aaron Mcneely, Huan Y. A. Meng, Mike Miller, Lawrence A. Molnar, Juan Carlos Morales, Brett M. Morris, Matthew W. Muterspaugh, David Nespra, Carrie R. Nugent, Katherine M. Nugent, A. Odasso, Derek O'Keeffe, Arto Oksanen, John M. O'Meara, András Ordasi, Hugh Osborn, John J. Ott, J. R. Parks, Diego Rodriguez Perez, Vance Petriew, Roger Pickard, András Pál, Peter Plavchan, Don Pollacco, Francisco Pozo-Nuñez, Francisco J. Pozuelos, Steve Rau, Seth Redfield, Howard Relles, Ignasi Ribas, Jon Richards, Joonas L. O. Saario, Emily J. Safron, J. Martin Sallai, Krisztián Sárneczky, Bradley E. Schaefer, Clea F. Schumer, Madison Schwartzendruber, Michael H. Siegel, Andrew P. V. Siemion, Brooke D. Simmons, Joshua D. Simon, Sergio Simón-Díaz, Michael L. Sitko, Hector Socas-Navarro, Ádám Sódor, Donn Starkey, Iain A. Steele, Geoff Stone, Klaus G. Strassmeier, Rachel A. Street, Tricia Sullivan, Jari Suomela, Jon J. Swift, Gyula M. Szabó, Róbert Szabó, Róbert Szakáts, Tamás Szalai, Angelle M. Tanner, Borja Toledo-Padrón, Tamás Tordai, Amaury H. M. J. Triaud, Jake D. Turner, Joseph H. Ulowetz, Marian Urbanik, Siegfried Vanaverbeke, Andrew Vanderburg, Krisztián Vida, Brad P. Vietje, József Vinkó, Kaspar Von Braun, Elizabeth O. Waagen, Dan Walsh, Christopher A. Watson, R. C. Weir, Klaus Wenzel, Carlos Westendorp, Michael W. Williamson, Jason T. Wright, Mark C. Wyatt, Weikang Zheng, Gabriella Zsidi

Information Systems and Engineering Management Research Publications

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 …


An Hst/Stis Optical Transmission Spectrum Of Warm Neptune Gj 436b, Joshua D. Lothringer, Björn Benneke, Ian J. M. Crossfield, Gregory W. Henry, Caroline Morley, Diana Dragomir, Travis Barman, Heather Knutson, Eliza Kempton, Jonathan J. Fortney, Peter Mccullough, Andrew W. Howard Jan 2018

An Hst/Stis Optical Transmission Spectrum Of Warm Neptune Gj 436b, Joshua D. Lothringer, Björn Benneke, Ian J. M. Crossfield, Gregory W. Henry, Caroline Morley, Diana Dragomir, Travis Barman, Heather Knutson, Eliza Kempton, Jonathan J. Fortney, Peter Mccullough, Andrew W. Howard

Information Systems and Engineering Management Research Publications

GJ 436b is a prime target for understanding warm Neptune exoplanet atmospheres and a target for multiple James Webb Space Telescope (JWST) Guaranteed Time Observation programs. Here, we report the first space-based optical transmission spectrum of the planet using two Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) transit observations from 0.53 to 1.03 μm. We find no evidence for alkali absorption features, nor evidence of a scattering slope longward of 0.53 μm. The spectrum is indicative of moderate to high metallicity (∼100–1000× solar), while moderate-metallicity scenarios (∼100× solar) require aerosol opacity. The optical spectrum also rules out some …


Differential Rotation In Magnetic Chemically Peculiar Stars, Zdeněk Mikulášek, Jiří Krtička, Ernst Paunzen, Michal Švanda, Stefan Hummerich, Klaus Bernhard, Miroslav Jagelka, Jan Janík, Gregory W. Henry, Matthew E. Shultz Jan 2018

Differential Rotation In Magnetic Chemically Peculiar Stars, Zdeněk Mikulášek, Jiří Krtička, Ernst Paunzen, Michal Švanda, Stefan Hummerich, Klaus Bernhard, Miroslav Jagelka, Jan Janík, Gregory W. Henry, Matthew E. Shultz

Information Systems and Engineering Management Research Publications

Magnetic chemically peculiar (mCP) stars constitute about 10% of upper-main-sequence stars and are characterized by strong magnetic fields and abnormal photospheric abundances of some chemical elements. Most of them exhibit strictly periodic light, magnetic, radio, and spectral variations that can be fully explained by a rigidly rotating main-sequence star with persistent surface structures and a stable global magnetic field. Long-term observations of the phase curves of these variations enable us to investigate possible surface differential rotation with unprecedented accuracy and reliability. The analysis of the phase curves in the best-observed mCP stars indicates that the location and the contrast of …


Orbital Misalignment Of The Neptune-Mass Exoplanet Gj 436b With The Spin Of Its Cool Star, Vincent Bourrier, Christophe Lovis, Hervé Beust, David Ehrenreich, Gregory W. Henry, Nicola Astudillo-Defru, Romain Allart, Xavier Bonfils, Damien Ségransan, Xavier Delfosse, Heather M. Cegla, Aurélien Wyttenbach, Kevin Heng, Baptiste Lavie, Francesco Pepe Dec 2017

Orbital Misalignment Of The Neptune-Mass Exoplanet Gj 436b With The Spin Of Its Cool Star, Vincent Bourrier, Christophe Lovis, Hervé Beust, David Ehrenreich, Gregory W. Henry, Nicola Astudillo-Defru, Romain Allart, Xavier Bonfils, Damien Ségransan, Xavier Delfosse, Heather M. Cegla, Aurélien Wyttenbach, Kevin Heng, Baptiste Lavie, Francesco Pepe

Information Systems and Engineering Management Research Publications

The angle between the spin of a star and the orbital planes of its planets traces the history of the planetary system. Exoplanets orbiting close to cool stars are expected to be on circular, aligned orbits because of strong tidal interactions with the stellar convective envelope. Spin–orbit alignment can be measured when the planet transits its star, but such ground-based spectroscopic measurements are challenging for cool, slowly rotating stars. Here we report the three-dimensional characterization of the trajectory of an exoplanet around an M dwarf star, derived by mapping the spectrum of the stellar photosphere along the chord transited by …


The Discovery And Mass Measurement Of A New Ultra-Short-Period Planet: K2-131b, Fei Dai, Joshua N. Winn, Davide Gandolfi, Sharon X. Wang, Johanna K. Teske, Jennifer Burt, Simon Albrecht, Oscar Barragán, William D. Cochran, Michael Endl, Malcolm Fridlund, Artie P. Hatzes, Teruyuki Hirano, Lea A. Hirsch, Marshall C. Johnson, Anders Bo Justesen, John Livingston, Carina M. Persson, Jorge Prieto-Arranz, Andrew Vanderburg, Roi Alonso, Giuliano Antoniciello, Pamela Arriagada, R. Paul Butler, Juan Cabrera, Jeffrey D. Crane, Felice Cusano, Szilárd Csizmadia, Hans Deeg, Sergio B. Dieterich, Philipp Eigmüller, Anders Erikson, Mark E. Everett, Akihiko Fukui, Sascha Grziwa, Eike W. Guenther, Gregory W. Henry, Steve B. Howell, John Asher Johnson, Judith Korth, Masayuki Kuzuhara, Norio Narita, David Nespral, Grzegorz Nowak, Enric Palle, Martin Pätzold, Heike Rauer, Pilar Montañés Rodríguez, Stephen A. Shectman, Alexis M. S. Smith, Ian B. Thompson, Vincent Van Eylen, Michael W. Williamson, Robert A. Wittenmyer Nov 2017

The Discovery And Mass Measurement Of A New Ultra-Short-Period Planet: K2-131b, Fei Dai, Joshua N. Winn, Davide Gandolfi, Sharon X. Wang, Johanna K. Teske, Jennifer Burt, Simon Albrecht, Oscar Barragán, William D. Cochran, Michael Endl, Malcolm Fridlund, Artie P. Hatzes, Teruyuki Hirano, Lea A. Hirsch, Marshall C. Johnson, Anders Bo Justesen, John Livingston, Carina M. Persson, Jorge Prieto-Arranz, Andrew Vanderburg, Roi Alonso, Giuliano Antoniciello, Pamela Arriagada, R. Paul Butler, Juan Cabrera, Jeffrey D. Crane, Felice Cusano, Szilárd Csizmadia, Hans Deeg, Sergio B. Dieterich, Philipp Eigmüller, Anders Erikson, Mark E. Everett, Akihiko Fukui, Sascha Grziwa, Eike W. Guenther, Gregory W. Henry, Steve B. Howell, John Asher Johnson, Judith Korth, Masayuki Kuzuhara, Norio Narita, David Nespral, Grzegorz Nowak, Enric Palle, Martin Pätzold, Heike Rauer, Pilar Montañés Rodríguez, Stephen A. Shectman, Alexis M. S. Smith, Ian B. Thompson, Vincent Van Eylen, Michael W. Williamson, Robert A. Wittenmyer

Information Systems and Engineering Management Research Publications

We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet, K2-131b, was discovered in K2 Campaign 10. It has a radius of ${1.81}_{-0.12}^{+0.16}\,{R}_{\oplus }$ and orbits a G dwarf with a period of 8.9 hr. Radial velocities obtained with Magellan/PFS and TNG/HARPS-N show evidence for stellar activity along with orbital motion. We determined the planetary mass using two different methods: (1) the "floating chunk offset" method, based only on changes in velocity observed on the same night; and (2) a Gaussian …


Contemporaneous Imaging Comparisons Of The Spotted Giant Σ Geminorum Using Interferometric, Spectroscopic, And Photometric Data, Rachael M. Roettenbacher, John D. Monnier, Heidi Korhonen, Robert O. Harmon, Fabien Baron, Thomas Hackman, Gregory W. Henry, Gail H. Schaefer, Klaus G. Strassmeier, Michael Weber, Theo A. Ten Brummelaar Nov 2017

Contemporaneous Imaging Comparisons Of The Spotted Giant Σ Geminorum Using Interferometric, Spectroscopic, And Photometric Data, Rachael M. Roettenbacher, John D. Monnier, Heidi Korhonen, Robert O. Harmon, Fabien Baron, Thomas Hackman, Gregory W. Henry, Gail H. Schaefer, Klaus G. Strassmeier, Michael Weber, Theo A. Ten Brummelaar

Information Systems and Engineering Management Research Publications

Nearby active stars with relatively rapid rotation and large starspot structures offer the opportunity to compare interferometric, spectroscopic, and photometric imaging techniques. In this paper, we image a spotted star with three different methods for the first time. The giant primary star of the RS Canum Venaticorum binary σ Geminorum (σ Gem) was imaged for two epochs of interferometric, high-resolution spectroscopic, and photometric observations. The light curves from the reconstructions show good agreement with the observed light curves, supported by the longitudinally consistent spot features on the different maps. However, there is strong disagreement in the spot latitudes across the …


Hubble Pancet: An Isothermal Day-Side Atmosphere For The Bloated Gas-Giant Hat-P-32ab, Nikolay Nikolov, David K. Sing, Jayesh M. Goyal, Gregory W. Henry, Hannah R. Wakeford, Thomas M. Evans, Mercedes López-Morales, Antonio García Muñoz, Lofti Ben-Jaffel, Jorge Sanz-Forcada, Gilda E. Ballester, Tiffany Kataria, Joanna K. Barstow, Vincent Bourrier, Lars A. Buchhave, Ofer Cohen, Drake Deming, David Ehrenreich, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikole K. Lewis, Avi M. Mandell, Michael H. Williamson Nov 2017

Hubble Pancet: An Isothermal Day-Side Atmosphere For The Bloated Gas-Giant Hat-P-32ab, Nikolay Nikolov, David K. Sing, Jayesh M. Goyal, Gregory W. Henry, Hannah R. Wakeford, Thomas M. Evans, Mercedes López-Morales, Antonio García Muñoz, Lofti Ben-Jaffel, Jorge Sanz-Forcada, Gilda E. Ballester, Tiffany Kataria, Joanna K. Barstow, Vincent Bourrier, Lars A. Buchhave, Ofer Cohen, Drake Deming, David Ehrenreich, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikole K. Lewis, Avi M. Mandell, Michael H. Williamson

Information Systems and Engineering Management Research Publications

We present a thermal emission spectrum of the bloated hot Jupiter HAT-P-32Ab from a single eclipse observation made in spatial scan mode with the Wide Field Camera 3 (WFC3) aboard the Hubble Space Telescope (HST). The spectrum covers the wavelength regime from 1.123 to 1.644 μm which is binned into 14 eclipse depths measured to an averaged precision of 104 parts-per million. The spectrum is unaffected by a dilution from the close M-dwarf companion HAT-P-32B, which was fully resolved. We complemented our spectrum with literature results and performed a comparative forward and retrieval analysis with the 1D radiative-convective ATMO model. …


The Quadruple-Lined, Doubly Eclipsing System V482 Persei, Guillermo Torres, Claud H. Sandberg Lacy, Francis C. Fekel, Marek Wolf, Matthew W. Muterspaugh Sep 2017

The Quadruple-Lined, Doubly Eclipsing System V482 Persei, Guillermo Torres, Claud H. Sandberg Lacy, Francis C. Fekel, Marek Wolf, Matthew W. Muterspaugh

Information Systems and Engineering Management Research Publications

We report spectroscopic and differential photometric observations of the A-type system V482 Per, which reveal it to be a rare hierarchical quadruple system containing two eclipsing binaries. One binary has the previously known orbital period of 2.4 days and a circular orbit, and the other a period of 6 days, a slightly eccentric orbit (e = 0.11), and shallow eclipses only 2.3% deep. The two binaries revolve around their common center of mass in a highly elongated orbit (e = 0.85) with a period of 16.67 yr. Radial velocities are measured for all components from our quadruple-lined spectra and are …


New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. X. Hd 96511, Hr 7578, And Kz Andromedae, Francis C. Fekel, Gregory W. Henry, Jocelyn Tomkin Aug 2017

New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. X. Hd 96511, Hr 7578, And Kz Andromedae, Francis C. Fekel, Gregory W. Henry, Jocelyn Tomkin

Information Systems and Engineering Management Research Publications

From an extensive number of newly acquired radial velocities we determine the orbital elements for three late-type dwarf systems, HD 96511, HR 7578, and KZ And. The orbital periods are 18.89737 ± 0.00002, 46.81610 ± 0.00006, and 3.0329113 ± 0.0000005 days, respectively, and all three systems are eccentric, although KZ And is just barely so. We have detected lines of the secondary of HD 96511 for the first time. The orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) of the binary components all have accuracies of 0.2% or better. …


An Ultrahot Gas-Giant Exoplanet With A Stratosphere, Thomas M. Evans, David K. Sing, Tiffany Kataria, Jayesh M. Goyal, Nikolay Nikolov, Hannah R. Wakeford, Drake Deming, Mark S. Marley, David S. Amundsen, Gilda E. Ballester, Joanna K. Barstow, Lofti Ben-Jaffel, Vincent Bourrier, Lars A. Buchhave, Ofer Cohen, David Ehrenreich, Antonio García Muñoz, Gregory W. Henry, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikole K. Lewis, Mercedes López-Morales, Avi M. Mandell, Jorge Sanz-Forcada, Pascal Tremblin, Roxana Lupu Aug 2017

An Ultrahot Gas-Giant Exoplanet With A Stratosphere, Thomas M. Evans, David K. Sing, Tiffany Kataria, Jayesh M. Goyal, Nikolay Nikolov, Hannah R. Wakeford, Drake Deming, Mark S. Marley, David S. Amundsen, Gilda E. Ballester, Joanna K. Barstow, Lofti Ben-Jaffel, Vincent Bourrier, Lars A. Buchhave, Ofer Cohen, David Ehrenreich, Antonio García Muñoz, Gregory W. Henry, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikole K. Lewis, Mercedes López-Morales, Avi M. Mandell, Jorge Sanz-Forcada, Pascal Tremblin, Roxana Lupu

Information Systems and Engineering Management Research Publications

Infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere. If upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum. Conversely, if there is a stratosphere—where temperature increases with altitude—these molecular features will be observed in emission. It has been suggested that stratospheres could form in highly irradiated exoplanets, but the extent to which this occurs is unresolved both theoretically and observationally. A previous claim for the presence of a stratosphere remains open to question, owing to the challenges posed by the …


Orbital Elements And Stellar Parameters Of The Active Binary Ux Arietis, Christian A. Hummel, John D. Monnier, Rachael M. Roettenbacher, Guillermo Torres, Gregory W. Henry, Heidi Korhonen, Anthony Beasley, Gail H. Schaefer, Nils H. Turner, Theo A. Ten Brummelaar, Chris D. Farrington, Judit Sturmann, Laszlo Sturmann, Frédérique Baron, Stefan Kraus Jul 2017

Orbital Elements And Stellar Parameters Of The Active Binary Ux Arietis, Christian A. Hummel, John D. Monnier, Rachael M. Roettenbacher, Guillermo Torres, Gregory W. Henry, Heidi Korhonen, Anthony Beasley, Gail H. Schaefer, Nils H. Turner, Theo A. Ten Brummelaar, Chris D. Farrington, Judit Sturmann, Laszlo Sturmann, Frédérique Baron, Stefan Kraus

Information Systems and Engineering Management Research Publications

Stellar activity observed as large surface spots, radio flares, or emission lines is often found in binary systems. UX Arietis exhibits these signs of activity, originating on the K0 subgiant primary component. Our aim is to resolve the binary, measure the orbital motion, and provide accurate stellar parameters such as masses and luminosities to aid in the interpretation of the observed phenomena. Using the CHARA six-telescope optical long-baseline array on Mount Wilson, California, we obtained amplitudes and phases of the interferometric visibility on baselines up to 330 m in length, resolving the two components of the binary. We reanalyzed archival …


Kepler Sheds New And Unprecedented Light On The Variability Of A Blue Supergiant: Gravity Waves In The O9.5iab Star Hd 188209, Conny Aerts, Sergio Símon-Díaz, Steven Bloemen, Jonas Debosscher, Péter I. Pápics, Steve Bryson, M. Still, Ehsan Moravveji, Michael H. Williamson, Frank Grundahl, Mads Fredslund Andersen, Victoria Antoci, Pere L. Pallé, Jørgen Christensen-Dalsgaard, Tamara M. Rogers May 2017

Kepler Sheds New And Unprecedented Light On The Variability Of A Blue Supergiant: Gravity Waves In The O9.5iab Star Hd 188209, Conny Aerts, Sergio Símon-Díaz, Steven Bloemen, Jonas Debosscher, Péter I. Pápics, Steve Bryson, M. Still, Ehsan Moravveji, Michael H. Williamson, Frank Grundahl, Mads Fredslund Andersen, Victoria Antoci, Pere L. Pallé, Jørgen Christensen-Dalsgaard, Tamara M. Rogers

Information Systems and Engineering Management Research Publications

Stellar evolution models are most uncertain for evolved massive stars. Asteroseismology based on high-precision uninterrupted space photometry has become a new way to test the outcome of stellar evolution theory and was recently applied to a multitude of stars, but not yet to massive evolved supergiants.Our aim is to detect, analyse and interpret the photospheric and wind variability of the O9.5 Iab star HD 188209 from Kepler space photometry and long-term high-resolution spectroscopy. We used Kepler scattered-light photometry obtained by the nominal mission during 1460 d to deduce the photometric variability of this O-type supergiant. In addition, we assembled and …


General Model For Light Curves Of Chromospherically Active Binary Stars, Lauri Jetsu, Gregory W. Henry, Jyri J. Lehtinen Mar 2017

General Model For Light Curves Of Chromospherically Active Binary Stars, Lauri Jetsu, Gregory W. Henry, Jyri J. Lehtinen

Information Systems and Engineering Management Research Publications

The starspots on the surface of many chromospherically active binary stars concentrate on long-lived active longitudes separated by 180°. Shifts in activity between these two longitudes, the "flip-flop" events, have been observed in single stars like FK Comae and binary stars like σ Geminorum. Recently, interferometry has revealed that ellipticity may at least partly explain the flip-flop events in σ Geminorum. This idea was supported by the double-peaked shape of the long-term mean light curve of this star. Here we show that the long-term mean light curves of 14 chromospherically active binaries follow a general model that explains the connection …


Characterization Of The Wolf 1061 Planetary System, Stephen R. Kane, Kaspar Von Braun, Gregory W. Henry, Miranda A. Waters, Tabetha S. Boyajian, Andrew W. Mann Jan 2017

Characterization Of The Wolf 1061 Planetary System, Stephen R. Kane, Kaspar Von Braun, Gregory W. Henry, Miranda A. Waters, Tabetha S. Boyajian, Andrew W. Mann

Information Systems and Engineering Management Research Publications

A critical component of exoplanetary studies is an exhaustive characterization of the host star, from which the planetary properties are frequently derived. Of particular value are the radius, temperature, and luminosity, which are key stellar parameters for studies of transit and habitability science. Here we present the results of new observations of Wolf 1061, known to host three super-Earths. Our observations from the Center for High Angular Resolution Astronomy interferometric array provide a direct stellar radius measurement of 0.3207 ± 0.0088 R⊙, from which we calculate the effective temperature and luminosity using spectral energy distribution models. We obtained 7 yr …


Hst Pancet Program: A Cloudy Atmosphere For The Promising Jwst Target Wasp-101b, Hannah R. Wakeford, Kevin B. Stevenson, Nikole K. Lewis, David K. Sing, Mercedes López-Morales, Mark S. Marley, Tiffany Kataria, Avi M. Mandell, Gilda E. Ballester, Joanna K. Barstow, Lofti Ben-Jaffel, Vincent Bourrier, Lars A. Buchhave, David Ehrenreich, Thomas M. Evans, Antonio García Muñoz, Gregory W. Henry, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikolay Nikolov, Jorge Sanz-Forcada Jan 2017

Hst Pancet Program: A Cloudy Atmosphere For The Promising Jwst Target Wasp-101b, Hannah R. Wakeford, Kevin B. Stevenson, Nikole K. Lewis, David K. Sing, Mercedes López-Morales, Mark S. Marley, Tiffany Kataria, Avi M. Mandell, Gilda E. Ballester, Joanna K. Barstow, Lofti Ben-Jaffel, Vincent Bourrier, Lars A. Buchhave, David Ehrenreich, Thomas M. Evans, Antonio García Muñoz, Gregory W. Henry, Heather Knutson, Panayotis Lavvas, Alain Lecavelier Des Etangs, Nikolay Nikolov, Jorge Sanz-Forcada

Information Systems and Engineering Management Research Publications

We present results from the first observations of the Hubble Space Telescope (HST) Panchromatic Comparative Exoplanet Treasury program for WASP-101b, a highly inflated hot Jupiter and one of the community targets proposed for the James Webb Space Telescope (JWST) Early Release Science (ERS) program. From a single HST Wide Field Camera 3 observation, we find that the near-infrared transmission spectrum of WASP-101b contains no significant H2O absorption features and we rule out a clear atmosphere at 13σ. Therefore, WASP-101b is not an optimum target for a JWST ERS program aimed at observing strong molecular transmission features. We compare WASP-101b to …


Infrared Spectroscopy Of Symbiotic Stars. Xi. Orbits For Southern S-Type Systems: Hen 3-461, Sy Mus, Hen 3-828, And Ar Pav, Francis C. Fekel, Kenneth H. Hinkle, Richard R. Joyce, Peter R. Wood Dec 2016

Infrared Spectroscopy Of Symbiotic Stars. Xi. Orbits For Southern S-Type Systems: Hen 3-461, Sy Mus, Hen 3-828, And Ar Pav, Francis C. Fekel, Kenneth H. Hinkle, Richard R. Joyce, Peter R. Wood

Information Systems and Engineering Management Research Publications

Employing new infrared radial velocities, we have computed spectroscopic orbits of the cool giants in four southern S-type symbiotic systems. The orbits for two of the systems, Hen 3-461 and Hen 3-828, have been determined for the first time, while orbits of the other two, SY Mus and AR Pav, have previously been determined. For the latter two systems, we compare our results with those in the literature. The low mass of the secondary of SY Mus suggests that it has gone through a common envelope phase. Hen 3-461 has an orbital period of 2271 days, one of the longest …


Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell Nov 2016

Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell

Information Systems and Engineering Management Research Publications

We acquired differential UBV photoelectric photometry and radial velocities of the relatively bright, understudied, massive Algol binary ET Tau and utilized the Wilson-Devinney (WD) analysis program to obtain a simultaneous solution of these observations. To improve the orbital ephemeris, the V measurements from the ASAS program were also analyzed. Because of the very rapid rotation of the significantly more massive and hotter component (B2/3 spectral class), only radial velocities of the secondary component, which has a ∼B7 spectral class, could be measured. We derive masses of ${M}_{1}=14.34\pm 0.28\,{M}_{\odot }$ and ${M}_{2}=6.339\pm 0.117\,{M}_{\odot }$ and equal-volume radii of ${R}_{1}=6.356\pm 0.056\,{R}_{\odot }$ …


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 …