The Collapse of the Wien Tail in the Coldest Brown Dwarf? Hubble Space Telescope Near-infrared Photometry of WISE J085510.83-071442.5

June 2016 • 2016ApJ...823L..35S

Authors • Schneider, Adam C. • Cushing, Michael C. • Kirkpatrick, J. Davy • Gelino, Christopher R.

Abstract • We present Hubble Space Telescope (HST) near-infrared photometry of the coldest known brown dwarf, WISE J085510.83-071442.5 (WISE 0855-0714). WISE 0855-0714 was observed with the Wide Field Camera 3 (WFC3) on board HST using the F105W, F125W, and F160W filters, which approximate the Y, J, and H near-infrared bands. WISE 0855-0714 is undetected at F105W with a corresponding 2σ magnitude limit of ∼26.9. We marginally detect WISE 0855-0714 in the F125W images (S/N ∼ 4), with a measured magnitude of 26.41 ± 0.27, more than a magnitude fainter than the J-band magnitude reported by Faherty et al. WISE J0855-0714 is clearly detected in the F160W band, with a magnitude of 23.86 ± 0.03, the first secure detection of WISE 0855-0714 in the near-infrared. Based on these data, we find that WISE 0855-0714 has extremely red {{F}}105{{W}}-{{F}}125{{W}} and {{F}}125{{W}}-{{F}}160{{W}} colors relative to other known Y dwarfs. We find that when compared to the models of Saumon et al. and Morley et al., the {{F}}105{{W}}-{{F}}125{{W}} and {{F}}125{{W}}-{{F}}160{{W}} colors of WISE 0855-0714 cannot be accounted for simultaneously. These colors likely indicate that we are seeing the collapse of flux on the Wien tail for this extremely cold object.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2016ApJ...823L..35S
• PDF https://stacks.iop.org/2041-8205/823/L35/pdf
• PREPRINT http://arxiv.org/abs/1605.05618
• DATA https://archive.stsci.edu/mastbibref.php?bibcode=2016ApJ...823L..35S
• DATA https://hst.esac.esa.int/ehst/#/pages/search;bibcode=2016ApJ...823L..35S
• ELECTR https://doi.org/10.3847%2F2041-8205%2F823%2F2%2FL35