Star formation at the epoch of reionization with CANUCS : the ages of stellar populations in MACS1149-JD1

Bradač, Maruša (author), Harshan Thevalil, Anishya (author), Martis, Nicholas S. (author), Rihtaršič, Gregor (author)

We present measurements of stellar populations properties of a $z$ = 9.1 gravitationally lensed galaxy MACS1149-JD1 using deep James Webb Space Telescope NIRISS slitless spectroscopy as well as NIRISS and NIRCam imaging from the CAnadian NIRISS Unbiased Cluster Survey (CANUCS). The galaxy is split into four components. Three magnified ($μ$ ∼ 11) star-forming components are unresolved, giving intrinsic sizes of < 25 pc. In addition, the underlying extended component contains the bulk of the stellar mass, formed the majority of its stars ∼50 Myr earlier than the other three components, and is not the site of the most active star formation currently. The NIRISS and NIRCam resolved photometry does not confirm a strong Balmer break previously seen in Spitzer. The NIRISS grism spectrum has been extracted for the entire galaxy and shows a clear continuum and Lyman break, with no Ly$α$ detected.

• Language: English
• Keywords: high-redshift galaxies, gravitational lensing, reionization
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 7 str.
• Numbering: Vol. 961, no. 1, art. L21
• PID: 20.500.12556/RUL-154284-1f236e93-9dfd-5d69-a6bf-a99570f17eb4
• UDC: 524.8
• ISSN on article: 2041-8213
• DOI: 10.3847/2041-8213/ad0e73
• COBISS.SI-ID: 182919427
• Publication date in RUL: 05.02.2024

Record is a part of a journal

• Title: The Astrophysical journal. Letters
• Shortened title: Astrophys. J. Lett.
• Publisher: American Astronomical Society
• ISSN: 2041-8213
• COBISS.SI-ID: 367233

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.