Discovery of a new Y dwarf: WISE J030449.03-270508.3

October 2014 • 2014MNRAS.444.1931P

Authors • Pinfield, D. J. • Gromadzki, M. • Leggett, S. K. • Gomes, J. • Lodieu, N. • Kurtev, R. • Day-Jones, A. C. • Ruiz, M. T. • Cook, N. J. • Morley, C. V. • Marley, M. S. • Marocco, F. • Smart, R. L. • Jones, H. R. A. • Lucas, P. W. • Beletsky, Y. • Ivanov, V. D. • Burningham, B. • Jenkins, J. S. • Cardoso, C. • Frith, J. • Clarke, J. R. A. • Gálvez-Ortiz, M. C. • Zhang, Z.

Abstract • We present a new Y dwarf, WISE J030449.03-270508.3, confirmed from a candidate sample designed to pick out low-temperature objects from the Wide-field Infrared Survey Explorer (WISE) data base. The new object is typed Y0pec following a visual comparison with spectral standards, and lies at a likely distance of 10-17 pc. Its tangential velocity suggests thin disc membership, but it shows some spectral characteristics that suggest that it may be metal poor and/or older than previously identified Y0 dwarfs. Based on trends seen for warmer late-type T dwarfs, the Y-band flux peak morphology is indicative of sub-solar metallicity, and the enhanced red wing of the J-band flux peak offers evidence for high gravity and/or low metallicity (with associated model trends suggesting an age closer to ∼10 Gyr and mass in the range 0.02-0.03 M). This object may thus be extending the population parameter space of the known Y0 dwarfs.


IPAC Authors

Federico Marocco

Assistant Scientist