activity
20172026
most citedAtmospheric Reconnaissance of TRAPPIST-1 b with JWST/NIRISS: Evidence for Strong Stellar Contamination in the Transmission Spectra

170 citations · 579 across the 27 of their papers we have counts for

collaborators

28 papers

astro-ph.EP2026

Radial velocity detection of the TRAPPIST-1 planetary system with SPIRou and NIRPS

Alexandrine L'Heureux, René Doyon, Charles Cadieux +57

The TRAPPIST-1 system is well-known for its seven transiting Earth-sized exoplanets. It has been extensively studied and characterized, notably with transit timing variations (TTVs…

astro-ph.EP2026

Atmospheric Reconnaissance of TRAPPIST-1 f with JWST NIRISS SOSS: No Evidence for the Transit Light Source Effect

Olivia Lim, René Doyon, Ryan J. MacDonald +25

In just over three years of operation, JWST has observed all seven planets of the TRAPPIST-1 system. The two innermost planets were found to have little to no atmosphere, barring t…

astro-ph.SR2026

A single power law for the TRAPPIST-1 flare distribution across four orders of magnitude in energy

Valeriy Vasilyev, Alexander I. Shapiro, Nadiia Kostogryz +10

TRAPPIST-1 is an ultra-cool dwarf that flares frequently. These flares shape the surrounding planets' high-energy irradiation environments, with consequences for atmospheric chemis…

astro-ph.EP2026★ 3 cited

Super-Earth masses and stellar abundances from NIRPS reveal tentative evidence for water-rich formation around M dwarfs

Drew Weisserman, Nicole Gromek, Ryan Cloutier +98

Tracing the compositional link between terrestrial super-Earths and their host stars provides clues to their dominant formation pathway. By constraining the stellar abundances of r…

astro-ph.EP2026

NIRPS tightens the mass estimate of GJ 3090 b and detects a planet near the stellar rotation period

Pierrot Lamontagne, Drew Weisserman, Charles Cadieux +148

We present an updated characterization of the planetary system orbiting the nearby M2 dwarf GJ 3090 (TOI-177; pc), based on new high-precision radial velocity (RV) observa…

astro-ph.EP2025★ 2 cited

Separating flare and secondary atmospheric signals with RADYN modeling of near-infrared JWST transmission spectroscopy observations of TRAPPIST-1

Ward S. Howard, Adam F. Kowalski, Michael Radica +10

Although TRAPPIST-1's temperate planets have the highest transmission signals of any known system, flares contaminate 50-70% of transits at the 1000 ppm level, far above 100 ppm se…

astro-ph.EP2025★ 5 cited

NIRPS and TESS reveal a peculiar system around the M dwarf TOI-756: A transiting sub-Neptune and a cold eccentric giant

Léna Parc, François Bouchy, Neil J. Cook +148

The Near InfraRed Planet Searcher (NIRPS) joined HARPS on the 3.6-m ESO telescope at La Silla Observatory in April 2023, dedicating part of its Guaranteed Time Observations (GTO) p…

astro-ph.EP2025★ 1 cited

Strict limits on potential secondary atmospheres on the temperate rocky exo-Earth TRAPPIST-1 d

Caroline Piaulet-Ghorayeb, Björn Benneke, Martin Turbet +23

The nearby TRAPPIST-1 system, with its seven small rocky planets orbiting a late-type M8 star, offers an unprecedented opportunity to search for secondary atmospheres on temperate…

astro-ph.EP2025★ 2 cited

Quantifying thermal water dissociation in the dayside photosphere of WASP-121 b using NIRPS

Luc Bazinet, Romain Allart, Björn Benneke +119

The intense stellar irradiation of ultra-hot Jupiters results in some of the most extreme atmospheric environments in the planetary regime. On their daysides, temperatures can be s…

astro-ph.EP2025

Flares on TRAPPIST-1 reveal the spectrum of magnetic features on its surface

Valeriy Vasilyev, Nadiia Kostogryz, Alexander I. Shapiro +11

TRAPPIST-1 is an M8 dwarf hosting seven known exoplanets and is currently one of the most frequently observed targets of the James Webb Space Telescope (JWST). However, it is notor…

astro-ph.EP2025★ 10 cited

Enriched volatiles and refractories but deficient titanium on the dayside atmosphere of WASP-121b revealed by JWST/NIRISS

Stefan Pelletier, Louis-Philippe Coulombe, Jared Splinter +21

With dayside temperatures elevated enough for all atmospheric constituents to be present in gas form, ultra-hot Jupiters offer a unique opportunity to probe the composition of gian…

astro-ph.IM2025★ 29 cited

NIRPS joining HARPS at ESO 3.6 m. On-sky performance and science objectives

Francois Bouchy, Rene Doyon, Francesco Pepe +131

The Near-InfraRed Planet Searcher (NIRPS) is a high-resolution, high-stability near-infrared (NIR) spectrograph equipped with an AO system. Installed on the ESO 3.6-m telescope, it…

astro-ph.EP2025★ 11 cited

Diving into the planetary system of Proxima with NIRPS -- Breaking the metre per second barrier in the infrared

Alejandro Suárez Mascareño, Étienne Artigau, Lucile Mignon +138

We obtained 420 high-resolution spectra of Proxima, over 159 nights, using the Near Infra Red Planet Searcher (NIRPS). We derived 149 nightly binned radial velocity measurements wi…

astro-ph.EP2025★ 6 cited

NIRPS detection of delayed atmospheric escape from the warm and misaligned Saturn-mass exoplanet WASP-69b

Romain Allart, Yann Carteret, Vincent Bourrier +119

Near-infrared high-resolution echelle spectrographs unlock access to fundamental properties of exoplanets, from their atmospheric escape and composition to their orbital architectu…

astro-ph.EP2025

Blind search for activity-sensitive lines in the near-infrared using HARPS and NIRPS observations of Proxima and Gl 581

João Gomes da Silva, Elisa Delgado-Mena, Nuno C. Santos +145

Stellar activity variability is one of the main obstacles to the detection of Earth-like planets using the RV method. The aim of this work is to measure the effect of activity in t…

astro-ph.EP2025★ 8 cited

Hydride ion continuum hides absorption signatures in the NIRPS near-infrared transmission spectrum of the ultra-hot gas giant WASP-189b

Valentina Vaulato, Stefan Pelletier, David Ehrenreich +77

Ultra-hot Jupiters showcase extreme atmospheric conditions, including molecular dissociation, ionisation, and significant day-to-night temperature contrasts. Their close proximity…

astro-ph.EP2024★ 19 cited

Transmission spectroscopy of WASP-52 b with JWST NIRISS: Water and helium atmospheric absorption, alongside prominent star-spot crossings

Marylou Fournier-Tondreau, Yanbo Pan, Kim Morel +20

In the era of exoplanet studies with JWST, the transiting, hot gas giant WASP-52 b provides an excellent target for atmospheric characterization through transit spectroscopy. WASP-…

astro-ph.EP2024

Updated forecast for TRAPPIST-1 times of transit for all seven exoplanets incorporating JWST data

Eric Agol, Natalie H. Allen, Björn Benneke +12

The TRAPPIST-1 system has been extensively observed with JWST in the near-infrared with the goal of measuring atmospheric transit transmission spectra of these temperate, Earth-siz…

astro-ph.EP2024★ 1 cited

Promise and Peril: Stellar Contamination and Strict Limits on the Atmosphere Composition of TRAPPIST-1c from JWST NIRISS Transmission Spectra

Michael Radica, Caroline Piaulet-Ghorayeb, Jake Taylor +9

Attempts to probe the atmospheres of rocky planets around M dwarfs present both promise and peril. While their favorable planet-to-star radius ratios enable searches for even thin…

astro-ph.EP2024★ 2 cited

Transmission Spectroscopy of the Habitable Zone Exoplanet LHS 1140 b with JWST/NIRISS

Charles Cadieux, René Doyon, Ryan J. MacDonald +20

LHS 1140 b is the second-closest temperate transiting planet to the Earth with an equilibrium temperature low enough to support surface liquid water. At 1.7300.025 R,…

astro-ph.IM2024

NIRPS first light and early science: breaking the 1 m/s RV precision barrier at infrared wavelengths

Étienne Artigau, François Bouchy, René Doyon +111

The Near-InfraRed Planet Searcher or NIRPS is a precision radial velocity spectrograph developed through collaborative efforts among laboratories in Switzerland, Canada, Brazil, Fr…

astro-ph.EP2023

Characterizing the Near-infrared Spectra of Flares from TRAPPIST-1 During JWST Transit Spectroscopy Observations

Ward S. Howard, Adam F. Kowalski, Laura Flagg +16

We present the first analysis of JWST near-infrared spectroscopy of stellar flares from TRAPPIST-1 during transits of rocky exoplanets. Four flares were observed from 0.6--2.8 m…

astro-ph.EP2023★ 36 cited

A roadmap for the atmospheric characterization of terrestrial exoplanets with JWST

TRAPPIST-1 JWST Community Initiative, :, Julien de Wit +80

Ultra-cool dwarf stars are abundant, long-lived, and uniquely suited to enable the atmospheric study of transiting terrestrial companions with JWST. Amongst them, the most prominen…

astro-ph.EP2023★ 64 cited

Near-Infrared Transmission Spectroscopy of HAT-P-18b with NIRISS: Disentangling Planetary and Stellar Features in the Era of JWST

Marylou Fournier-Tondreau, Ryan J. MacDonald, Michael Radica +24

The JWST Early Release Observations (ERO) included a NIRISS/SOSS (0.6-2.8m) transit of the 850K Saturn-mass exoplanet HAT-P-18b. Initial analysis of these data…