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Related papers: Ghost in the time series: no planet for Alpha Cen …

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Early time-series photometry from NASA's Kepler spacecraft has revealed a planet transiting the star we term Kepler-4, at RA = 19h02m27.68s, Dec = +50:08:08.7. The planet has an orbital period of 3.213 days and shows transits with a…

[abridged]The aim of this work is to search for planets around evolved stars, with a special focus on stars more massive than 2\,M$_\odot$ in light of previous findings that show a drop in planet occurrence around stars above this mass. We…

Earth and Planetary Astrophysics · Physics 2023-11-22 E. Delgado Mena , J. Gomes da Silva , J. P. Faria , N. C. Santos , J. H. Martins , M. Tsantaki , A. Mortier , S. G. Sousa , C. Lovis

A radial velocity (RV) survey to detect central stars in binary systems was carried out between 2002 and 2004. De Marco et al. (2004) reported that 10 out of 11 monitored stars exhibited strong RV variability, but periods were not detected.…

Astrophysics · Physics 2007-09-12 Orsola De Marco , S. Wortel , Howard E. Bond , Dianne Harmer

We investigate the possibility of constraining the sin i degeneracy of alpha Cen B b -- with orbital period P=3.24 d; a = 0.042 AU; msini = 1.1 M_earth -- to estimate the true mass of the newly reported terrestrial exoplanet in the nearest…

Solar and Stellar Astrophysics · Physics 2015-06-11 Peter Plavchan , Xi Chen , Garrett Pohl

We report the discovery of a radial velocity signal that can be interpreted as a planetary-mass candidate orbiting the K dwarf HD26965, with an orbital period of 42.364$\pm$0.015 days, or alternatively, as the presence of residual,…

Using images from the Helioseismic and Magnetic Imager aboard the \textit{Solar Dynamics Observatory} (SDO/HMI), we extract the radial-velocity (RV) signal arising from the suppression of convective blue-shift and from bright faculae and…

We confirm the trend in the radial velocity data for Epsilon Indi A suggesting a long-period planetary companion and find significant curvature is present, sufficient to quantify Epsilon Indi Ab as a cold Jupiter with a minimum mass of…

Earth and Planetary Astrophysics · Physics 2018-03-23 Fabo Feng , Mikko Tuomi , Hugh R. A. Jones

Deneb, the prototype Alpha Cygni variable, is a bright A2 Ia supergiant which shows irregular variability with a 12-day quasi-period, presumed to be caused by pulsations. At the 2023 AAVSO Annual Meeting we discussed radial velocity and…

Solar and Stellar Astrophysics · Physics 2025-03-27 Joyce A. Guzik , Brian Kloppenborg , Noel Richardson , Jason Jackiewicz , Nancy Morrison , Tom Calderwood , Andrzej Pigulski

Earth-like planets orbiting in the habitable zone of K- to G-type stars create an RV effect in amplitude of less than 1 \si{\meter\per\second} and have orbital periods of hundreds of days. Only long-term RV surveys with sub-meter per second…

Aims: We investigate long-term radial velocity (RV) variability in the K-dwarf star GJ 1137 (HD 93083, HIP52521), a known Saturn-mass exoplanet host, and assess the role of stellar activity in shaping the observed signals. Methods: We…

CONTEXT: Most current radial velocity planet search programs have concentrated on stars of one solar mass. Our knowledge on the frequency of giant planets and brown dwarf companions to more massive stars is thus rather limited. In the case…

Earth and Planetary Astrophysics · Physics 2010-11-02 E. W. Guenther , M. Hartmann , M. Esposito , A. P. Hatzes , F. Cusano , D. Gandolfi

GJ1132 is a nearby red dwarf known to host a transiting Earth-size planet. After its initial detection, we pursued an intense follow-up with the HARPS velocimeter. We now confirm the detection of GJ1132b with radial velocities only. We…

Context. Radial velocity (RV) measurements induced by the presence of planets around late-type stars are contaminated by stellar signals that are of the order of a few meters per second in amplitude, even for the quietest stars. Those…

Solar and Stellar Astrophysics · Physics 2023-01-04 K. Al Moulla , X. Dumusque , P. Figueira , G. Lo Curto , N. C. Santos , F. Wildi

Context. The development of refined instruments and techniques for a detailed analysis of the radial velocities (RVs) of stars other than the Sun allows the presence of planetary signals of amplitude below 1 ms$^{-1}$ to be investigated.…

Strong selection effects are present in observational samples of cataclysmic variables (CVs), complicating comparisons to theoretical predictions. The selection criteria used to define most CV samples discriminate heavily against the…

Astrophysics · Physics 2009-11-13 Magaretha L. Pretorius , Christian Knigge

The interaction between Earth-like exoplanets and the magnetic field of low-mass host stars are considered to produce weak emission signals at radio frequencies. A study using LOFAR data announced the detection of radio emission from the…

We present precision radial velocity (RV) data that reveal a multiple exoplanet system orbiting the bright nearby G5V star 61 Virginis. Our 4.6 years of combined Keck/HIRES and Anglo-Australian Telescope precision RVs indicate the hitherto…

Radial velocity (RV) searches for Earth-mass exoplanets in the habitable zone around Sun-like stars are limited by the effects of stellar variability on the host star. In particular, suppression of convective blueshift and brightness…

Proxima Centauri is the closest star to the Sun. This small, low-mass, mid M dwarf is known to host an Earth-mass exoplanet with an orbital period of 11.2 days within the habitable zone, as well as a long-period planet candidate with an…