Browsing Research publications by Author "Anglada-Escude, Guillem"

Now showing items 1-11 of 11

    • Comment on "Stellar activity masquerading as planets in the habitable zone of the M dwarf Gliese 581" 

      Tuomi, Mikko; Anglada-Escude, Guillem (2015-03-06)
      Robertson et al. (Reports, 25 July 2014, p. 440) claimed that activity-induced variability is responsible for the Doppler signal of the proposed planet candidate GJ 581d. We point out that their analysis using periodograms ...

    • A dynamically-packed planetary system around GJ 667C with three super-Earths in its habitable zone 

      Anglada-Escude, Guillem; Tuomi, Mikko; Gerlach, Enrico; Barnes, Rory; Heller, Rene; Jenkins, James S.; Wende, Sebastian; Vogt, Steven S.; Butler, R. Paul; Reiners, Ansgar; Jones, H.R.A. (2013-08-07)
      Context. Since low-mass stars have low luminosities, orbits at which liquid water can exist on Earth-sized planets are relatively close-in, which produces Doppler signals that are detectable using state-of-the-art Doppler ...

    • Habitable-zone super-Earth candidate in a six-planet system around the K2.5V star HD 40307 

      Tuomi, Mikko; Anglada-Escude, Guillem; Gerlach, E.; Jones, H.R.A.; Reiners, A.; Rivera, Eugenio J.; Vogt, S.; Butler, R.P. (2013-01)
      Context. The K2.5 dwarf HD 40307 has been reported to host three super-Earths. The system lacks massive planets and is therefore a potential candidate for having additional low-mass planetary companions. Aims. We re-derive ...

    • Highly replicable, low-cost, portable, general-purpose, high-resolution spectrometer with applications in stellar studies and exoplanet science 

      Baker, Clark; Anglada-Escude, Guillem; Jones, Hugh; Martin, Bill (SPIE, 2019-09-09)
      High-resolution spectrometers have proven to be an important tool for astronomical observations and continue to have an ever expanding set of applications, such as high resolution IFS (Integral Field Spectroscopy). With ...

    • MagAO Imaging of Long-period Objects (MILO). II. A Puzzling White Dwarf around the Sun-like Star HD 11112 

      Rodigas, Timothy J.; Bergeron, P.; Simon, Amelie; Arriagada, Pamela; Faherty, Jackie; Anglada-Escude, Guillem; Mamajek, Eric E.; Weinberger, Alycia; Butler, R. Paul; Males, Jared R.; Morzinski, Katie; Close, Laird M.; Hinz, Philip M.; Bailey, Jeremy; Carter, Brad; Jenkins, James S.; Jones, Hugh; O'Toole, Simon; Tinney, C. G.; Wittenmyer, Rob; Debes, John (2016-11-10)
      HD 11112 is an old, Sun-like star that has a long-term radial velocity (RV) trend indicative of a massive companion on a wide orbit. Here we present direct images of the source responsible for the trend using the Magellan ...

    • PEXO : a global modeling framework for nanosecond timing, microsecond astrometry, and μm/s radial velocities 

      Feng, Fabo; Lisogorskyi, Maksym; Jones, Hugh R. A.; Kopeikin, Sergei M.; Butler, R. Paul; Anglada-Escude, Guillem; Boss, Alan P. (2019-10-15)
      The ability to make independent detections of the signatures of exoplanets with complementary telescopes and instruments brings a new potential for robust identification of exoplanets and precision characterization. We ...

    • A planetary system around the nearby M dwarf GJ 667C with at least one super-earth in its habitable zone 

      Anglada-Escude, Guillem; Arriagada, Pamela; Vogt, Steven S.; Rivera, Eugenio J.; Butler, R. Paul; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Minniti, Dante; Haghighipour, Nader; Carter, Brad D.; Tinney, C.G.; Wittenmyer, Robert A.; Bailey, Jeremy A.; O'Toole, Simon J.; Jones, H.R.A.; Jenkins, J.S. (2012-05-20)
      We re-analyze 4 years of HARPS spectra of the nearby M1.5 dwarf GJ 667C available through the European Southern Observatory public archive. The new radial velocity (RV) measurements were obtained using a new data analysis ...

    • Radial velocity studies of cool stars 

      Jones, H.R.A.; Barnes, J.R.; Tuomi, Mikko; Jenkins, James S.; Anglada-Escude, Guillem (2014-04-28)
      Our current view of exoplanets is one derived primarily from solar-like stars with a strong focus on understanding our Solar System. Our knowledge about the properties of exoplanets around the dominant stellar population ...

    • A terrestrial planet candidate in a temperate orbit around Proxima Centauri 

      Anglada-Escude, Guillem; Amado, Pedro J.; Barnes, John; Berdinas, Zaira M.; Butler, Paul; Coleman, Gavin A. L.; de la Cueva, Ignacio; Dreizler, Stefan; Endl, Michael; Giesers, Benjamin; Jeffers, Sandra V.; Jenkins, James S.; Jones, Hugh; Kiraga, Marcin; Kurster, Martin; Lopez-Gonzalez, Maria J.; Marvin, Christopher J.; Morales, Nicolas; Morin, Julien; Nelson, Richard P.; Ortiz, Jose L.; Ofir, Aviv; Paardekooper, Sijme-Jan; Reiners, Ansgar; Rodriguez, Eloy; Rodriguez-Lopez, Cristina; Sarmiento, Luis F.; Strachan, John P.; Tsapras, Yiannis; Tuomi, Mikko; Zechmeister, Mathias (2016-08-25)
      At a distance of 1.295 parsecs, the red dwarf Proxima Centauri (α Centauri C, GL 551, HIP 70890 or simply Proxima) is the Sun’s closest stellar neighbour and one of the best-studied low-mass stars. It has an effective ...

    • Two planets around Kapteyn's star: a cold and a temperate super-Earth orbiting the nearest halo red dwarf 

      Anglada-Escude, Guillem; Arriagada, P.; Tuomi, Mikko; Zechmeister, M.; Jenkins, J. S.; Ofir, A.; Dreizler, S.; Gerlach, E.; Marvin, C. J.; Reiners, A.; Jeffers, S. V.; Butler, R.P.; Vogt, S. S.; Amado, P. J.; Gerlach, E.; Rodríguez-López, C.; Berdiñas, Z. M.; Morin, J.; Crane, J. D.; Shectman, S. A.; Thompson, Ian B.; Diaz, M.; Rivera, E.; Sarmiento, L. F.; Jones, Hugh (2014-09-01)
      Exoplanets of a few Earth masses can be now detected around nearby low-mass stars using Doppler spectroscopy. In this Letter, we investigate the radial velocity variations of Kapteyn's star, which is both a sub-dwarf M-star ...

    • Up to four planets around the M dwarf GJ 163 : Sensitivity of Bayesian planet detection criteria to prior choice 

      Tuomi, Mikko; Anglada-Escude, Guillem (2013-08-05)
      Context. Exoplanet Doppler surveys are currently the most efficient means to detect low-mass companions to nearby stars. Among these stars, the light M dwarfs provide the highest sensitivity to detect low-mass exoplanet ...