We have conducted an extremely deep spectroscopic survey of the NGC 1333 young star cluster using NIRISS on the JWST to identify and characterize the lowest-mass free-floating objects in its midst. Our observations cover 19 known brown dwarfs, for most of which we confirm previously assigned spectral types. We discover six new candidates with L-dwarf spectral types that are plausible...
A successful theory of star formation should predict the number of objects as a function of their mass produced through star-forming events. Previous studies in star-forming regions and the solar neighborhood have identified a mass function increasing from the hydrogen-burning limit down to about 10 MJ. Theory predicts a limit to the fragmentation process, providing a natural turnover in the...
Age-benchmark brown dwarfs' and planetary-mass objects' spectroscopy is key to characterize substellar evolution. In this paper we present the JHK medium resolution (R$\sim$3000) spectra of 25 7-76 $\mathrm{M_{Jup}}$ (spectral types L3.0-M6.0) brown dwarfs and planetary-mass objects in the Orion Nebula Cluster obtained with MOSFIRE installed at the W. M. Keck\,I telescope. We obtained the...
We present a new generation of ATMO2020 atmosphere models which is appropriate for application to studies low mass stars, brown dwarfs and rogue planetary-mass objects. The models compute temperature–pressure profiles and emergent spectra for atmospheres in both radiative–convective equilibrium and non-equilibrium chemistry, covering effective temperatures and surface gravities within the...
