The northern census of M dwarfs within 100 pc, and its potential for exoplanet surveys

Lépine, Sébastien; Gaidos, Eric

doi:10.1002/asna.201211769

Cited by 9 publications

(11 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, none of these M dwarfs has metallicities below Fe/H = −1.0 dex and none is classified as a subdwarf from low-resolution optical spectroscopy (Alonso-Floriano et al 2015), placing an upper limit of 0.3% of M subdwarfs in the CARMENES sample. Similarly, only one source within 20 pc (Gl 809) is classified as a subdwarf among the 1564 bright (J ≤9 mag) M dwarfs in the catalogue of Lépine & Gaidos (2013), resulting in a ratio of 0.064% broadly consistent with the proportion of late-type subdwarfs to solar-metallicity stars from a photometric sample of ∼100 sources with spectroscopic follow-up (∼0. 02% Lodieu et al 201202% Lodieu et al , 2017.…”

Section: Density Of Metal-poor Brown Dwarfsmentioning

confidence: 82%

Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5−101002.3

Lodieu

Osorio

Martín

et al. 2022

A&A

View full text Add to dashboard Cite

Aims. Our goal is to characterise the physical properties of the metal-poor brown dwarf population. In particular, we focus on the recently discovered peculiar dwarf WISE1810055−1010023. Methods. We collected optical iz and near-infrared J-band imaging on multiple occasions over 1.5 years to derive accurate trigonometric parallax and proper motion of the metal-depleted ultra-cool dwarf candidate WISE J1810055−1010023. We also acquired low-resolution optical spectroscopy (0.6−1.0 µm) and new infrared (0.9−1.3 µm) spectra of WISE J1810055−1010023 that were combined with our photometry, other existing data from the literature and our trigonometric distance to determine the object's luminosity from the integration of the observed spectral energy distribution covering from 0.6 through 16 µm. We compared the full optical and infrared spectrum with state-of-the-art atmosphere models to further constrain its effective temperature, surface gravity and metallicity. Results. WISE J1810055−1010023 is detected in the iz bands with AB magnitudes of i = 23.871±0.104 and z = 20.147±0.083 mag in the Panoramic Survey Telescope and Rapid Response System (PanSTARRS) system. It does not show any obvious photometric variability beyond 0.1−0.2 mag in any of the z-and J-band filters. The very red z − J ≈ 2.9 mag colour is compatible with an ultra-cool dwarf nature. Fitting for parallax and proper motion, we measure a trigonometric parallax of 112.5 +8.1 −8.0 mas for WISE J1810055−1010023, placing the object at only 8.9 +0.7 −0.6 pc, about three times closer than previously thought. We employed Monte Carlo methods to estimate the error on the parallax and proper motion. The object's luminosity was determined at log L/L = −5.78 ± 0.11 dex. From the comparison to atmospheric models, we infer a likely metallicity of [Fe/H] ≈ −1.5 and an effective temperature cooler than 1000 K. The estimated luminosity and temperature of this object are below the known substellar limit. Despite its apparent low metallicity, we derive space motions that are more typical of the old disc than the halo of the Milky Way. We confirm that WISE J1810055−1010023 has an ultra-cool temperature and belongs to a new class of objects with no known spectral counterparts among field L-and T-type dwarfs. Conclusions. WISE J1810055−1010023 is a very special substellar object and represents a new addition to the 10 pc sample. The optical to near-infrared spectra show strong features due to water vapour and H 2 collision induced absorption. Our trigonometric distance has strong implications on the density of metal-poor brown dwarfs in the solar vicinity, which may be higher than that of metal-poor stars.

show abstract

Section: Density Of Metal-poor Brown Dwarfsmentioning

confidence: 82%

Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5−101002.3

Lodieu

Osorio

Martín

et al. 2022

A&A

View full text Add to dashboard Cite

show abstract

“…For the complete sample within 100 pc, our TRILEGALbased estimates of the total numbers of M dwarfs (∼190,000) are lower than those of both Sozzetti et al (2014;∼415,000), and those implied by the northern 100 pc M dwarf census of Lépine & Gaidos (2013), from which we infer a fullsky estimate of ∼270,000 (including a contribution of 30% due to incompleteness). Our corresponding numbers of planet detections at >3σ fov are also somewhat less than those estimated by Sozzetti et al (635 compared to 2600): while Sozzetti et al (2014) predicted ∼40 transiting systems, we find essentially none (1.1 ± 1.1).…”

Section: Dwarfsmentioning

confidence: 88%

ASTROMETRIC EXOPLANET DETECTION WITHGAIA

Perryman

Hartman

Bakos

et al. 2014

ApJ

335

307

View full text Add to dashboard Cite

We provide a revised assessment of the number of exoplanets that should be discovered by Gaia astrometry, extending previous studies to a broader range of spectral types, distances, and magnitudes. Our assessment is based on a large representative sample of host stars from the TRILEGAL Galaxy population synthesis model, recent estimates of the exoplanet frequency distributions as a function of stellar type, and detailed simulation of the Gaia observations using the updated instrument performance and scanning law. We use two approaches to estimate detectable planetary systems: one based on the signal-to-noise ratio of the astrometric signature per field crossing, easily reproducible and allowing comparisons with previous estimates, and a new and more robust metric based on orbit fitting to the simulated satellite data. With some plausible assumptions on planet occurrences, we find that some 21,000 (±6000) high-mass (∼1-15M J ) long-period planets should be discovered out to distances of ∼500 pc for the nominal 5 yr mission (including at least 1000-1500 around M dwarfs out to 100 pc), rising to some 70,000 (±20,000) for a 10 yr mission. We indicate some of the expected features of this exoplanet population, amongst them ∼25-50 intermediate-period (P ∼ 2-3 yr) transiting systems.

show abstract

“…The HADES RV programme has completed the 6 th semester of observations. The complete original sample is composed by 106 stars, ranging from dM0 to dM3 spectral type, selected from the (Lépine & Gaidos 2013) and Palomar/Michigan State University (PMSU, Reid et al 1995) catalogs, with the additional criterion to be part of the APACHE catalog (Sozzetti et al 2013), with a visible magnitude lower than 12 and with a high number of Gaia mission scans. The M stars are photometrically monitored also by the EXORAP program at Serra La Nave.…”

Section: The Hades Rv Programmementioning

confidence: 99%

HADES RV program with HARPS-N at the TNG GJ 3998: An early M-dwarf hosting a system of super-Earths

Affer

Micela

Damasso

et al. 2016

A&A

106

View full text Add to dashboard Cite

Context. Many efforts to detect Earth-like planets around low-mass stars are presently devoted in almost every extra-solar planet search. M dwarfs are considered ideal targets for Doppler radial velocity searches because their low masses and luminosities make low-mass planets orbiting in their habitable zones more easily detectable than those around higher mass stars. Nonetheless, the statistics of frequency of low-mass planets hosted by low mass stars remains poorly constrained. Aims. Our M-dwarf radial velocity monitoring with HARPS-N within the GAPS (Global architectures of Planetary Systems) -ICE (Institut de Ciències de l'Espai/CSIC-IEEC) -IAC (Instituto de Astrofísica de Canarias) project ⋆⋆ can provide a major contribution to the widening of the current statistics through the in-depth analysis of accurate radial velocity observations in a narrow range of spectral sub-types (79 stars, between dM0 to dM3). Spectral accuracy will enable us to reach the precision needed to detect small planets with a few earth masses. Our survey will bring a contribute to the surveys devoted to the search for planets around M-dwarfs, mainly focused on the M-dwarf population of the northern emisphere, for which we will provide an estimate of the planet occurence. Methods. We present here a long duration radial velocity monitoring of the M1 dwarf star GJ 3998 with HARPS-N to identify periodic signals in the data. Almost simultaneous photometric observations were carried out within the APACHE and EXORAP programs to characterize the stellar activity and to distinguish from the periodic signals those due to activity and to the presence of planetary companions. We run an MCMC simulation and use Bayesian model selection to determine the number of planets in this system, to estimate their orbital parameters and minimum masses and for a proper treatment of the activity noise. Results. The radial velocities have a dispersion in excess of their internal errors due to at least four superimposed signals, with periods of 30.7, 13.7, 42.5 and 2.65 days. Our data are well described by a 2-planet Keplerian (13.

show abstract

The northern census of M dwarfs within 100 pc, and its potential for exoplanet surveys

Cited by 9 publications

References 10 publications

Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5−101002.3

Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5−101002.3

ASTROMETRIC EXOPLANET DETECTION WITHGAIA

HADES RV program with HARPS-N at the TNG GJ 3998: An early M-dwarf hosting a system of super-Earths

Contact Info

Product

Resources

About