MagAO IMAGING OF LONG-PERIOD OBJECTS (MILO). II. A PUZZLING WHITE DWARF AROUND THE SUN-LIKE STAR HD 11112
AuthorRodigas, Timothy J.
Faherty, Jacqueline K.
Mamajek, Eric E.
Butler, R. Paul
Males, Jared R.
Close, Laird M.
Hinz, Philip M.
Jenkins, James S.
Tinney, C. G.
AffiliationUniv Arizona, Steward Observ
instrumentation: adaptive optics
stars: individual (HD 11112)
techniques: high angular resolution
techniques: radial velocities
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationMagAO IMAGING OF LONG-PERIOD OBJECTS (MILO). II. A PUZZLING WHITE DWARF AROUND THE SUN-LIKE STAR HD 11112 2016, 831 (2):177 The Astrophysical Journal
JournalThe Astrophysical Journal
Rights© 2016. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractHD 11112 is an old, Sun-like star that has a long-term radial velocity (RV) trend indicative of a massive companion on a wide orbit. Here we present direct images of the source responsible for the trend using the Magellan Adaptive Optics system. We detect the object (HD 11112B) at a separation of 2 2 (100 au) at multiple wavelengths spanning 0.6-4 mu m. and show that it is most likely a gravitationally bound cool white dwarf. Modeling its spectral energy distribution suggests that its mass is 0.9-1.1M(circle dot), which corresponds to very high eccentricity, near edge-on orbits from a. Markov chain Monte Carlo analysis of the RV and imaging data together. The total age of the white dwarf is > 2 sigma, which is discrepant with that of the primary star under most assumptions. The problem can be resolved if the white dwarf progenitor was initially a double white dwarf binary that then merged into the observed high-mass white dwarf. HD 11112B is a unique and intriguing benchmark object that can be used to calibrate atmospheric and evolutionary models of cool white dwarfs and should thus continue to be monitored by RV and direct imaging over the coming years.
VersionFinal published version
SponsorsNSERC Canada; Fund FRQ-NT (Quebec); Space Telescope Science Institute [HST-HF251366.001-A]; NASA [NAS5-26555]; National Aeronautics and Space Administration; National Science Foundation