Early Science with the Large Millimeter Telescope: Detection of Dust Emission in Multiple Images of a Normal Galaxy at z > 4 Lensed by a Frontier Fields Cluster

Authors

• Alexandra Pope, University of Massachusetts Amherst
• Alfredo Montaña, Instituto Nacional de Astrofísica
• Andrew Battisti, University of Massachusetts Amherst
• Marceau Limousin, Aix Marseille University
• Danilo Marchesini, Tufts University
• Grant W. Wilson, University of Massachusetts Amherst
• Stacy Alberts, University of Arizona
• Itziar Aretxaga, Instituto Nacional de Astrofísica
• Vladimir Avila-Reese, Universidad Nacional Autónoma de México
• José Ramón Bermejo-Climent, Universidad de La Laguna
• Gabriel Brammer, Space Telescope Science Institute
• Hector Bravo-Alfaro, Universidad de Guanajuato
• Daniela Calzetti, University of Massachusetts Amherst
• Ranga-Ram Chary, California Institute of Technology
• Ryan Cybulski, University of Massachusetts Amherst
• Mauro Giavalisco, University of Massachusetts Amherst
• David Hughes, Instituto Nacional de Astrofísica
• Erin Kado-Fong, Tufts University
• Erica Keller, National Radio Astronomy Observatory
• Allison Kirkpatrick, University of Massachusetts Amherst
• Ivo Labbe, Leiden University
• Daniel Lange-Vagle, Tufts University
• James Lowenthal, Smith CollegeFollow
• Eric Murphy, National Radio Astronomy Observatory
• Pascal Oesch, Yale University
• Daniel Rosa Gonzalez, Instituto Nacional de Astrofísica
• David Sánchez-Argüelles, Instituto Nacional de Astrofísica
• Heath Shipley, Tufts University
• Mauro Stefanon, Leiden University
• Olga Vega, Instituto Nacional de Astrofísica
• Katherine Whitaker, University of Massachusetts Amherst
• Christina C. Williams, University of Arizona
• Min Yun, University of Massachusetts Amherst
• Jorge A. Zavala, Instituto Nacional de Astrofísica
• Milagros Zeballos, Instituto Nacional de Astrofísica

Document Type

Article

Publication Date

4-1-2017

Publication Title

The Astrophysical Journal

Abstract

We directly detect dust emission in an optically detected, multiply imaged galaxy lensed by the Frontier Fields cluster MACSJ0717.5+3745. We detect two images of the same galaxy at 1.1 mm with the AzTEC camera on the Large Millimeter Telescope leaving no ambiguity in the counterpart identification. This galaxy, MACS0717_Az9, is at z > 4 and the strong lensing model (μ=7.5) allows us to calculate an intrinsic IR luminosity of 9.7 × 1010 Le and an obscured star formation rate of 14.6 ± 4.5 Me yr−1. The unobscured star formation rate from the UV is only 4.1 ± 0.3 Me yr−1, which means the total star formation rate (18.7 ± 4.5 Me yr−1) is dominated (75%–80%) by the obscured component. With an intrinsic stellar mass of only 6.9 × 109 Me, MACS0717_Az9 is one of only a handful of z > 4 galaxies at these lower masses that is detected in dust emission. This galaxy lies close to the estimated star formation sequence at this epoch. However, it does not lie on the dust obscuration relation (IRX-β) for local starburst galaxies and is instead consistent with the Small Magellanic Cloud attenuation law. This remarkable lower mass galaxy, showing signs of both low metallicity and high dust content, may challenge our picture of dust production in the early universe.

Keywords

galaxies: evolution, galaxies: high-redshift, galaxies: star formation, gravitational lensing: strong, infrared: galaxies, dust, extinction

Volume

838

Issue

137

DOI

https://doi.org/10.3847/1538-4357/aa6573

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Rights

© The Authors

Version

Version of Record

Recommended Citation

Pope, Alexandra; Montaña, Alfredo; Battisti, Andrew; et al, "Early Science with the Large Millimeter Telescope: Detection of Dust Emission in Multiple Images of a Normal Galaxy at z > 4 Lensed by a Frontier Fields Cluster" (2017). Astronomy: Faculty Publications, Smith College, Northampton, MA. https://scholarworks.smith.edu/ast_facpubs/2