559 citations · 8.9k across the 196 of their papers we have counts for
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Statistics on the population of distant substellar companions to nearby stars
Souleymane Ouedraogo, Étienne Artigau, Sié Zacharie Kam +5
Context. Wide substellar companions provide important benchmarks for studying the formation and evolution of brown dwarfs and giant planets. Their association with stellar primarie…
Silicate Clouds, SiO, and Molecular Trends across the L-T Sequence: A JWST/MIRI LRS Spectral Library of Brown Dwarfs
Sam Barber, Stanimir Metchev, Genaro Suárez +9
We present the results of a survey program with JWST's MIRI LRS that obtained 514 m R~100 spectra of twenty-three L0T6 dwarfs. This spectral type range spans the formation…
Magnetic field measurements in a sample of Class I and flat-spectrum protostars observed with SPIRou
L. Drouglazet, E. Alecian, A. Sousa +27
Magnetic fields play a crucial role throughout stellar evolution, regulating angular momentum, channelling accretion, and launching jets and outflows. While the magnetic properties…
Six-yr SPIRou monitoring of the young planet-host dwarf AU Mic
J. -F. Donati, P. I. Cristofari, C. Moutou +10
In this paper we revisit our spectropolarimetric and velocimetric analysis of the young M dwarf AU Mic based on data collected with SPIRou at the Canada-France-Hawaii telescope, ov…
Chemical Fingerprints of M Dwarfs: High-Resolution Spectroscopy on 31 M Dwarfs with SPIRou
Farbod Jahandar, René Doyon, Étienne Artigau +10
We extend the methodology introduced by Jahandar et al. (2024) to determine the effective temperature and chemical abundances of 31 slowly-rotating solar neighborhood M dwarfs (M1-…
New Cold Subdwarf Discoveries from Backyard Worlds and a Metallicity Classification System for T Subdwarfs
Adam J. Burgasser, Adam C. Schneider, Aaron M. Meisner +36
We report the results of a spectroscopic survey of candidate T subdwarfs identified by the Backyard Worlds: Planet 9 program. Near-infrared spectra of 31 sources with red co…
SPIRou observations of the young planet-hosting star PDS 70
J. -F. Donati, P. I. Cristofari, S. H. P. Alencar +14
This paper presents near-infrared spectropolarimetric and velocimetric observations of the young planet-hosting T Tauri star PDS 70, collected with SPIRou at the 3.6m Canada-France…
Measuring Sub-Kelvin Variations in Stellar Temperature with High-Resolution Spectroscopy
Étienne Artigau, Charles Cadieux, Neil J. Cook +11
The detection of stellar variability often relies on the measurement of selected activity indicators such as coronal emission lines and non-thermal emissions. On the flip side, the…
SPIRou spectropolarimetry of the T Tauri star TW Hydrae: magnetic fields, accretion and planets
J. -F. Donati, P. I. Cristofari, L. T. Lehmann +15
In this paper we report near-infrared observations of the classical T Tauri star TW Hya with the SPIRou high-resolution spectropolarimeter and velocimeter at the 3.6-m Canada-Franc…
The First High-Contrast Images of Near High-Mass X-Ray Binaries with Keck/NIRC2
M. Prasow-Émond, J. Hlavacek-Larrondo, K. Fogarty +10
Although the study of X-ray binaries has led to major breakthroughs in high-energy astrophysics, their circumbinary environment at scales of 100--10,000 astronomical units ha…
Long-term monitoring of large-scale magnetic fields across optical and near-infrared domains with ESPaDOnS, Narval and SPIRou. The cases of EV Lac, DS Leo, and CN Leo
S. Bellotti, J. Morin, L. T. Lehmann +18
Dynamo models of stellar magnetic fields for partly and fully convective stars are guided by observational constraints. Zeeman-Doppler imaging has revealed a variety of magnetic fi…
The classical T Tauri star CI Tau observed with SPIRou: magnetospheric accretion and planetary formation
J. -F. Donati, B. Finociety, P. I. Cristofari +15
We report new observations of the classical T~Tauri star CI~Tau with the SPIRou near-infrared spectropolarimeter and velocimeter at the Canada-France-Hawaii Telescope (CFHT) in lat…
Measuring small-scale magnetic fields of 44 M dwarfs from SPIRou spectra with ZeeTurbo
P. I. Cristofari, J. -F. Donati, C. Moutou +11
We present the results of an analysis aimed at probing the small-scale magnetic fields of M dwarfs observed with SPIRou, the nIR high-resolution spectro-polarimeter installed at th…
Monitoring the young planet host V1298 Tau with SPIRou: planetary system and evolving large-scale magnetic field
B. Finociety, J. -F. Donati, P. I. Cristofari +15
We report results of a spectropolarimetric monitoring of the young Sun-like star V1298~Tau based on data collected with the near-infrared spectropolarimeter SPIRou at the Canada-Fr…
Comprehensive High-resolution Chemical Spectroscopy of Barnard's Star with SPIRou
Farbod Jahandar, René Doyon, Étienne Artigau +17
Determination of fundamental parameters of stars impacts all fields of astrophysics, from galaxy evolution to constraining the internal structure of exoplanets. This paper presents…
Magnetic fields & rotation periods of M dwarfs from SPIRou spectra
J. -F. Donati, L. T. Lehmann, P. I. Cristofari +17
We present near-infrared spectropolarimetric observations of a sample of 43 weakly- to moderately-active M dwarfs, carried with SPIRou at the Canada-France-Hawaii Telescope in the…
Monitoring the large-scale magnetic field of AD~Leo with SPIRou, ESPaDOnS and Narval. Toward a magnetic polarity reversal?
S. Bellotti, J. Morin, L. T. Lehmann +23
One manifestation of dynamo action on the Sun is the 22-yr magnetic cycle, exhibiting a polarity reversal and a periodic conversion between poloidal and toroidal fields. For M dwar…
The magnetic field and multiple planets of the young dwarf AU~Mic
J. -F. Donati, P. I. Cristofari, B. Finociety +25
In this paper we present an analysis of near-infrared spectropolarimetric and velocimetric data of the young M dwarf AU Mic, collected with SPIRou at the Canada-France-Hawaii teles…
Constraining atmospheric parameters and surface magnetic fields with : an application to SPIRou spectra
P. I. Cristofari, J. -F. Donati, C. P. Folsom +8
We report first results on a method aimed at simultaneously characterising atmospheric parameters and magnetic properties of M dwarfs from high-resolution nIR spectra recorded with…
Near-IR and optical radial velocities of the active M dwarf star Gl 388 (AD Leo) with SPIRou at CFHT and SOPHIE at OHP: A 2.23 day rotation period and no evidence for a corotating planet
A. Carmona, X. Delfosse, S. Bellotti +36
Context: The search for extrasolar planets around the nearest M dwarfs is a crucial step towards identifying the nearest Earth-like planets. One of the main challenges in this sear…
Optical and near-infrared stellar activity characterization of the early M dwarf Gl~205 with SOPHIE and SPIRou
P. Cortes-Zuleta, I. Boisse, B. Klein +41
The stellar activity of M dwarfs is the main limitation for discovering and characterizing exoplanets orbiting them since it induces quasi-periodic RV variations. We aim to charact…
Stable accretion and episodic outflows in the young transition disk system GM Aurigae
J. Bouvier, A. Sousa, K. Pouilly +17
We investigate the structure and dynamics of the magnetospheric accretion region and associated outflows on a scale smaller than 0.1 au around the young transitional disk system GM…
New insights on the near-infrared veiling of young stars using CFHT/SPIRou data
A. P. Sousa, J. Bouvier, S. H. P. Alencar +10
Veiling is ubiquitous at different wavelength ranges in accreting stars. However, the origin of the veiling in the IR domain is not well understood. The accretion spot alone is not…
Estimating the atmospheric properties of 44 M dwarfs from SPIRou spectra
P. I. Cristofari, J. -F. Donati, T. Masseron +8
We describe advances on a method designed to derive accurate parameters of M dwarfs. Our analysis consists in comparing high-resolution infrared spectra acquired with the near-infr…