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.

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.

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.

TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data (2021)
Journal Article
Hellier, & Maxted. (2021). TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data. Astronomical Journal, https://doi.org/10.3847/1538-3881/ac223a

We report the first discovery of a transiting circumbinary planet detected from a single sector of Transiting Exoplanet Survey Satellite (TESS) data. During Sector 21, the planet TIC 172900988b transited the primary star and then five days later it t... Read More about TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data.

Discovery and characterization of the exoplanets WASP-148b and c - A transiting system with two interacting giant planets (2020)
Journal Article
Hellier, Smalley, & Maxted. (2020). Discovery and characterization of the exoplanets WASP-148b and c - A transiting system with two interacting giant planets. Astronomy and Astrophysics, https://doi.org/10.1051/0004-6361/202038296

We present the discovery and characterization of WASP-148, a new extrasolar system that includes at least two giant planets. The host star is a slowly rotating inactive late-G dwarf with a V = 12 magnitude. The planet WASP-148b is a hot Jupiter of 0.... Read More about Discovery and characterization of the exoplanets WASP-148b and c - A transiting system with two interacting giant planets.