Magellan Adaptive Optics Imaging of PDS 70: Measuring the Mass Accretion Rate of a Young Giant Planet within a Gapped Disk
Follete, Katherine B.
Close, Laird M.
AffiliationUniv Arizona, Lunar & Planetary Lab
planets and satellites: detection
planets and satellites: formation
stars: pre-main sequence
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationKevin Wagner et al 2018 ApJL 863 L8
JournalASTROPHYSICAL JOURNAL LETTERS
Rights© 2018. 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.
AbstractPDS 70b is a recently discovered and directly imaged exoplanet within the wide (greater than or similar to 40 au) cavity around PDS 70. Ongoing accretion onto the central star suggests that accretion onto PDS 70b may also be ongoing. We present the first high-contrast images at H alpha (656 nm) and nearby continuum (643 nm) of PDS 70 utilizing the MagAO system. The combination of these filters allows for the accretion rate of the young planet to be inferred, as hot infalling hydrogen gas will emit strongly at H alpha over the optical continuum. We detected a source in H alpha at the position of PDS 70b on two sequential nights in 2018 May, for which we establish a false positive probability of <0.1%. We conclude that PDS 70b is a young, actively accreting planet. We utilize the H alpha line luminosity to derive a mass accretion rate of (M) over dot = 10(-8 +/- 1) M-Jup yr(-1), where the large uncertainty is primarily due to the unknown amount of optical extinction from the circumstellar and circumplanetary disks. PDS 70b represents the second case of an accreting planet interior to a disk gap, and is among the early examples of a planet observed during its formation.
VersionFinal published version
SponsorsNASA's Science Mission Directorate; NASA Exoplanets Research Program [NNX16AD44G]; DFG priority program [SPP 1992, MU 4172/1-1]; NSF ATI ; NSF AAG program ; NASA XRP program [80NSSC18K0441]