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An ALMA Search for High-albedo Objects Among the Midsized Jupiter Trojan Population

Simpson, Anna M. and Brown, Michael E. and Schemel, Madeline J. and Butler, Bryan J. (2022) An ALMA Search for High-albedo Objects Among the Midsized Jupiter Trojan Population. Astronomical Journal, 164 (1). Art. No. 23. ISSN 0004-6256. doi:10.3847/1538-3881/ac559e.

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We use Atacama Large Millimeter Array (ALMA) measurements of 870 μm thermal emission from a sample of midsized (15–40 km diameter) Jupiter Trojan asteroids to search for high-albedo objects in this population. We calculate the diameters and albedos of each object using a thermal model which also incorporates contemporaneous Zwicky Transient Facility photometry to accurately measure the absolute magnitude at the time of the ALMA observation. We find that while many albedos are lower than reported from WISE, several small Trojans have high albedos independently measured both from ALMA and from WISE. The number of these high-albedo objects is approximately consistent with expectations of the number of objects that recently have undergone large-scale impacts, suggesting that the interiors of freshly-crated Jupiter Trojans could contain high-albedo materials such as ices.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Brown, Michael E.0000-0002-8255-0545
Butler, Bryan J.0000-0002-5344-820X
Alternate Title:An ALMA search for high albedo objects among the mid-sized Jupiter Trojan population
Additional Information:© 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 2021 September 7; revised 2022 February 1; accepted 2022 February 10; published 2022 June 28. This research is supported by the Caltech Student-Faculty Programs WAVE Fellowship funded by the Carl F. Braun Trust and by NSF Astronomy & Astrophysics Research Grant #2109212. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.1.01158.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. Based on observations obtained with the Samuel Oschin Telescope 48 inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. Major funding has been provided by the U.S. National Science Foundation under grant No. AST-1440341 and by the ZTF partner institutions: the California Institute of Technology, the Oskar Klein Centre, the Weizmann Institute of Science, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron, the University of Wisconsin- Milwaukee, and the TANGO Program of the University System of Taiwan. This work uses data obtained from the Asteroid Lightcurve Data Exchange Format (ALCDEF) database, which is supported by funding from NASA grant 80NSSC18K0851.
Group:Zwicky Transient Facility
Funding AgencyGrant Number
Caltech WAVE FellowshipUNSPECIFIED
Carl F. Braun TrustUNSPECIFIED
NSF Astronomy and Astrophysics FellowshipAST-2109212
ZTF partner institutionsUNSPECIFIED
Subject Keywords:Jupiter trojans; Asteroid surfaces
Issue or Number:1
Classification Code:Unified Astronomy Thesaurus concepts: Jupiter trojans (874); Asteroid surfaces (2209)
Record Number:CaltechAUTHORS:20220725-156423000
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Official Citation:Anna M. Simpson et al 2022 AJ 164 23
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:115822
Deposited By: George Porter
Deposited On:27 Jul 2022 17:04
Last Modified:27 Jul 2022 17:04

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