Related papers: A New Method for Characterizing Very-Low-Mass Comp…

We used the Project 1640 near-infrared coronagraph and integral field spectrograph to observe 19 young solar type stars. Five of these stars are known binary stars and we detected the late-type secondaries and were able to measure their JH…

By comparing near-infrared spectra with atmosphere models, we infer the effective temperature, surface gravity, projected rotational velocity, and radial velocity for 21 very-low-mass stars and brown dwarfs. The unique sample consists of…

We present an approach to identifying and characterizing unresolved, very low mass spectral blend binaries composed of late-M, L, and T dwarfs using machine learning methodologies. We generated and evaluated a series of hierarchical random…

Constraining L dwarf properties from their spectra is challenging. Near-infrared spectra probe a limited range of pressures, while many species condense within their photospheres. Condensation creates two complexities: gas-phase species…

We present complete near-infrared (0.85-2.45 um), low-resolution (~100) spectra of a sample of 26 disk L-dwarfs with reliable optical spectral type classification. The observations have been obtained with NICS at the TNG using a prism-based…

Aims. We present simulations of the perfomances of the future SPHERE IFS instrument designed for imaging extrasolar planets in the near infrared (Y, J, and H bands). Methods. We used the IDL package code for adaptive optics simulation…

We develop a method to identify the spectroscopic signature of unresolved L-dwarf ultracool companions, which compares the spectra of candidates and their associated control stars using spectral ratio differences and residual spectra. We…

We present new 0.9-2.45 $\mu$m spectroscopy ($R \sim 1000$), and $Y$, $J$, $H$, $K_s$, $L^\prime$ photometry, obtained at Gemini North, of three low-mass brown dwarf companions on wide orbits around young stars of the Upper Scorpius OB…

In this paper, we develop a spectral differential technique with which the dynamical mass of low-mass companions can be found. This method aims at discovering close companions to late-type stars by removing the stellar spectrum through a…

Analysis of initial observations from near-infrared sky surveys has shown that the resulting photometric catalogues, combined with far-red optical data, provide an extremely effective method of finding isolated, very low-temperature objects…

We present the results of a study aiming at retrieving the fundamental parameters of M dwarfs from spectra secured with SPIRou, the near-infrared high-resolution spectropolarimeter installed at the Canada-France-Hawaii Telescope (CFHT), in…

Extrasolar planets observation and characterization by high contrast imaging instruments is set to be a very important subject in observational astronomy. Dedicated instruments are being developed to achieve this goal with very high…

Project 1640 is a high-contrast imaging instrument recently commissioned at Palomar observatory. A combination of a coronagraph with an integral field spectrograph (IFS), Project 1640 is designed to detect and characterize extrasolar…

High-contrast imaging instruments are now being equipped with integral field spectrographs (IFS) to facilitate the detection and characterization of faint substellar companions. Algorithms currently envisioned to handle IFS data, such as…

We aim at building a method that efficiently identifies young low-mass stars and brown dwarfs from low-resolution near-infrared spectra, by studying gravity-sensitive features and their evolution with age. We built a dataset composed of all…

While radial velocity surveys have demonstrated that the population of gas giants peaks around $3~\text{au}$, the most recent high-contrast imaging surveys have only been sensitive to planets beyond $\sim~10~\text{au}$. Sensitivity at small…

We present a method for measuring the physical parameters of the coldest T-type brown dwarfs using low resolution near infrared spectra. By comparing H_2O- and H_2-sensitive spectral ratios between empirical data and theoretical atmosphere…

We present near-infrared spectra for a sample of T dwarfs, including eleven new discoveries made using the Two Micron All Sky Survey. These objects are distinguished from warmer (L-type) brown dwarfs by the presence of methane absorption…

We present new observations of the low-mass companion to HD 984 taken with the Gemini Planet Imager as a part of the Gemini Planet Imager Exoplanet Survey campaign. Images of HD 984 B were obtained in the J (1.12--1.3 micron) and H…

With a uniform VLT SINFONI data set of nine targets, we have developed an empirical grid of J,H,K spectra of the atmospheres of objects estimated to have very low substellar masses of \sim5-20 MJup and young ages of \sim1-50 Myr. Most of…