相关论文: Cloudless atmospheres for L/T dwarfs and extra-sol…

We present infrared spectra of brown dwarfs with spectral types from mid-L to T. The 0.9-2.5 $\mu$m spectra of three dwarfs found by the Sloan Digital Sky Survey contain absorption bands of both methane and carbon monoxide and bridge the…

The formation of clouds affects brown dwarf and planetary atmospheres of nearly all effective temperatures. Iron and silicate condense in L dwarf atmospheres and dissipate at the L/T transition. Minor species such as sulfides and salts…

We examine the hypothesis that the red near-infrared colors of some L dwarfs could be explained by a "dust haze" of small particles in their upper atmospheres. This dust haze would exist in conjunction with the clouds found in dwarfs with…

We examine the thermal evolution of a sequence of compact objects containing low-mass hadronic and high-mass quark-hadronic stars constructed from a microscopically motivated equation of state. The dependence of the cooling tracks in the…

Heterogeneous clouds or temperature perturbations in rotating brown dwarfs produce variability in the observed flux. We report time-resolved simultaneous observations of the variable T6.5 brown dwarf 2MASSJ22282889-431026 over the…

We show that the total habitable volume in the atmospheres of cool brown dwarfs with effective temperatures of $\sim 250$-$350$ K is possibly larger by two orders of magnitude than that of Earth-like planets. We also study the role of…

The coldest Y spectral type brown dwarfs are similar in mass and temperature to cool and warm ($\sim$200 -- 400 K) giant exoplanets. We can therefore use their atmospheres as proxies for planetary atmospheres, testing our understanding of…

Upper atmospheres of Hot Jupiters are subject to extreme radiation conditions that can result in rapid atmospheric escape. The composition and structure of the upper atmospheres of these planets are affected by the high-energy spectrum of…

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…

Although transit spectroscopy is a powerful method for studying the composition, thermal properties and dynamics of exoplanet atmospheres, only a few transiting terrestrial exoplanets will be close enough to allow significant transit…

A chemical evolution model following the evolution of the abundances of H, He, C, N, O and Fe for dwarf irregular and blue compact galaxies is presented. This model takes into account detailed nucleosynthesis and computes in detail the…

The observed masses and radii of sub-Neptunes are typically explained by the gas dwarf and the water world scenarios. While their evolutionary history on a population level has been proposed as a method to distinguish between these…

Giant planets and brown dwarfs are thought to form via a combination of pathways, including bottom-up mechanisms in which gas is accreted onto a solid core and top-down mechanisms in which gas collapses directly into a gravitationally-bound…

Characterizing the atmospheres of exoplanets and brown dwarfs is crucial for understanding their atmospheric physics and chemistry, searching for biosignatures, and investigating their formation histories. Recent advances in observational…

The James Webb Space Telescope (JWST) offers exceptional spectral resolution and wavelength coverage, which are essential for studying the coldest brown dwarfs, particularly Y dwarfs. These objects are at the cold end of the sub-stellar…

Observations of variability can provide valuable information about the processes of cloud formation and dissipation in brown dwarf atmospheres. Here we report the results of an independent analysis of archival data from the Brown dwarf…

We review recent theoretical progress aimed at understanding the formation and the early stages of evolution of giant planets, low-mass stars and brown dwarfs. Calculations coupling giant planet formation, within a modern version of the…

The atmospheres of brown dwarfs orbiting in close proximity to their parent white dwarf represent some of the most extreme irradiated environments known. Understanding their complex dynamical mechanisms pushes the limits of theoretical and…

The recent detections of temperate terrestrial planets orbiting nearby stars and the promise of characterizing their atmospheres motivates a need to understand how the diversity of possible planetary parameters affects the climate of…

Super-puffs are a class of low-mass, large-radius planets that have challenged planet formation and evolution models. Their high inferred H/He mass fractions, required to explain their physical sizes, would lead to rapid atmospheric escape,…