L-BAND SPECTROSCOPY WITH MAGELLAN-AO/Clio2: FIRST RESULTS ON YOUNG LOW-MASS COMPANIONS
AuthorStone, Jordan M.
Morzinski, Katie M.
Rodigas, Timothy J.
AffiliationUniv Arizona, Steward Observ
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationL-BAND SPECTROSCOPY WITH MAGELLAN-AO/Clio2: FIRST RESULTS ON YOUNG LOW-MASS COMPANIONS 2016, 829 (1):39 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 firstname.lastname@example.org.
AbstractL-band spectroscopy is a powerful probe of cool low-gravity atmospheres: the P, Q, and R branch fundamental transitions of methane near 3.3 mu m provide a sensitive probe of carbon chemistry; cloud thickness modifies the spectral slope across the band; and H-3(+) opacity can be used to detect aurorae. Many directly imaged gas-giant companions to nearby young stars exhibit L-band fluxes distinct from the field population of brown dwarfs at the same effective temperature. Here we describe commissioning the L-band spectroscopic mode of Clio2, the 1-5 mu m instrument behind the Magellan adaptive-optics system. We use this system to measure L-band spectra of directly imaged companions. Our spectra are generally consistent with the parameters derived from previous near-infrared spectra for these late M to early L type objects. Therefore, deviations from the field sequence are constrained to occur below 1500 K. This range includes the L-T transition for field objects and suggests that observed discrepancies are due to differences in cloud structure and CO/CH4 chemistry.
VersionFinal published version
SponsorsNASA [NNX11AK57G, NAS 5-26555]; NSF AAG grant ; state of Arizona Technology Research Initiative Fund Imaging Fellowship; National Aeronautics and Space Administration through Hubble Fellowship - Space Telescope Science Institute [HST-HF2-51349, HST-HF2-51366.001-A]; California Institute of Technology - NASA through the Sagan Fellowship