All Outputs (7)

The GAPS programme at TNG XL. A puffy and warm Neptune-sized planet and an outer Neptune-mass candidate orbiting the solar-type star TOI-1422 (2022)
Journal Article
Hellier. (2022). The GAPS programme at TNG XL. A puffy and warm Neptune-sized planet and an outer Neptune-mass candidate orbiting the solar-type star TOI-1422. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202244079

Context. Neptunes represent one of the main types of exoplanets and have chemical-physical characteristics halfway between rocky and gas giant planets. Therefore, their characterization is important for understanding and constraining both the formati... Read More about The GAPS programme at TNG XL. A puffy and warm Neptune-sized planet and an outer Neptune-mass candidate orbiting the solar-type star TOI-1422.

GJ 3090 b: one of the most favourable mini-Neptune for atmospheric characterisation (2022)
Journal Article
Hellier. (2022). GJ 3090 b: one of the most favourable mini-Neptune for atmospheric characterisation. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202243975

We report the detection of GJ 3090 b (TOI-177.01), a mini-Neptune on a 2.9-day orbit transiting a bright (K = 7.3 mag) M2 dwarf located at 22 pc. The planet was identified by the Transiting Exoplanet Survey Satellite and was confirmed with the High A... Read More about GJ 3090 b: one of the most favourable mini-Neptune for atmospheric characterisation.

The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc (2022)
Journal Article
Hellier. (2022). The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc. Astronomy & Astrophysics, 1 - 23. https://doi.org/10.1051/0004-6361/202243834

We report the discovery of a multiplanetary system transiting the M0 V dwarf HD 260655 (GJ 239, TOI-4599). The system consists of at least two transiting planets, namely HD 260655 b, with a period of 2.77 d, a radius of Rb = 1.240 ± 0.023 R?, a mass... Read More about The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc.

TOI-712: A System of Adolescent Mini-Neptunes Extending to the Habitable Zone (2022)
Journal Article
Hellier. (2022). TOI-712: A System of Adolescent Mini-Neptunes Extending to the Habitable Zone. Astronomical Journal, https://doi.org/10.3847/1538-3881/ac7954

As an all-sky survey, NASA's Transiting Exoplanet Survey Satellite (TESS) mission is able to detect the brightest and rarest types of transiting planetary systems, including young planets that enable study of the evolutionary processes that occur wit... Read More about TOI-712: A System of Adolescent Mini-Neptunes Extending to the Habitable Zone.

A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system (2022)
Journal Article
Hellier. (2022). A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system. Nature Astronomy, https://doi.org/10.1038/s41550-022-01641-y

It is commonly accepted that exoplanets with orbital periods shorter than one day, also known as ultra-short-period (USP) planets, formed further out within their natal protoplanetary disks before migrating to their current-day orbits via dynamical i... Read More about A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system.

The young HD 73583 (TOI-560) planetary system: two 10-M-circle plus mini-Neptunes transiting a 500-Myr-old, bright, and active K dwarf (2022)
Journal Article
Hellier. (2022). The young HD 73583 (TOI-560) planetary system: two 10-M-circle plus mini-Neptunes transiting a 500-Myr-old, bright, and active K dwarf. Monthly Notices of the Royal Astronomical Society, 1606 - 1627. https://doi.org/10.1093/mnras/stac638

We present the discovery and characterization of two transiting planets observed by TESS in the light curves of the young and bright (V = 9.67) star HD73583 (TOI-560). We perform an intensive spectroscopic and photometric space- and ground-based foll... Read More about The young HD 73583 (TOI-560) planetary system: two 10-M-circle plus mini-Neptunes transiting a 500-Myr-old, bright, and active K dwarf.

BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities (2022)
Journal Article
Maxted, & Hellier. (2022). BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities. Monthly Notices of the Royal Astronomical Society, 3571 - 3583. https://doi.org/10.1093/mnras/stac113

BEBOP is a radial-velocity survey that monitors a sample of single-lined eclipsing binaries, in search of circumbinary planets by using high-resolution spectrographs. Here, we describe and test the methods we use to identify planetary signals within... Read More about BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities.