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.


IPAC Authors

Chris Gelino

Associate Scientist


Davy Kirkpatrick

Senior Scientist