# # Program information file # PROGRAM_ID 2021A060 PROGRAM_TITLE Discovering the youngest free-floating planets: spectroscopic confirmation of candidate young brown dwarfs and planetary mass objects from a transformative survey of Sigma Orionis with the novel W-band filter PROGRAM_INV1 Belinda Damian PROGRAM_INV2 Jessy Jose PROGRAM_INV3 Beth Biller PROGRAM_INV4 Loic Albert PROGRAM_INV5 Katelyn Allers PROGRAM_SCICAT stellar PROGRAM_ABSTRACT_BEG Low-mass brown dwarfs and free-floating planets in star-forming regions are vital tracers of the low mass end of the star-formation and are key analogues to exoplanets around stars. The detection of these objects in star-forming regions allows physical studies of such objects in the mass range of extra-solar planets. The complete census of a star-forming cloud, to masses well below the deuterium-burning limit, will also constrain the very low-mass end of the IMF, a key test of theories for star and brown dwarf formation. We propose for spectroscopic confirmation of 5 candidate brown dwarf and planetary mass members [J<17 mag,20-50 MJup] of the 3 Myr Sigma Orionis star-forming region located at a distance of 300-350pc. This cluster serves as an excellent natural laboratory to study the formation and early evolution of stars and protoplanetary disks across the entire range of stellar masses, ranging from massive stars to low-mass objects such as brown dwarfs and free-floating planets. These targets were chosen from our deep [J~21mag, ~5 MJup] CFHT J,H,W-band observations and selected based on our robust W-band selection method. They also agree with the WISE color criteria for low-mass young objects. IRTF SpeX is the best instrument for these candidates, allowing high S/N low-resolution spectroscopy with only a modest amount of telescope time per candidate. Brown dwarf spectra at infrared wavelengths can be strongly affected by telluric water absorption, thus, these spectra must be taken at an extremely dry site such as Mauna Kea. Spectroscopic confirmation of these targets will provide the most complete sample of low-mass objects and also the strongest constraints to date on the planetary-mass IMF in the Sigma Orionis cluster. PROGRAM_ABSTRACT_END