Star Formation under a Cosmic Microscope: Highly Magnified <i>z</i> = 11 Galaxy behind the Bullet Cluster
Abstract We present measurements of stellar population properties of a newly discovered, spectroscopically confirmed, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>z</mml:mi> <mml:mo>=</mml:mo> <mml:mn>11.1</mml:mn> <mml:msubsup> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.26</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.11</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> , gravitationally lensed galaxy, using JWST NIRSpec PRISM spectroscopy and NIRCam imaging. The arc is highly magnified by the Bullet Cluster (magnification factor <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> <mml:mo>=</mml:mo> <mml:mn>14</mml:mn> <mml:mo>.</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.3</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>6.2</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> ). It contains three star-forming components of which one is barely resolved and two are unresolved, giving intrinsic sizes of ≲10 pc. The clumps also contain ∼50% of the total stellar mass. The galaxy formed the majority of its stars ∼150 Myr ago (by z ∼ 14). The spectrum shows a pronounced damping wing, typical for galaxies deep in the reionization era and indicating a neutral intergalactic medium at this line of sight. The intrinsic luminosity of the galaxy is <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>0.08</mml:mn> <mml:msubsup> <mml:mrow> <mml:mn>6</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.030</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.008</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em"/> <mml:msup> <mml:mrow> <mml:mi>L</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>*</mml:mo> </mml:mrow> </mml:msup> </mml:math> (with L * being the characteristic luminosity for this redshift), making it the lowest-luminosity spectroscopically confirmed galaxy at z > 10 discovered to date.
Authors
- Gaël Noirot
- Anishya Harshan (ORCID: https://orcid.org/0000-0001-9414-6382)
- C. Jones (ORCID: https://orcid.org/0000-0003-2206-4243)
- Maruša Bradač (ORCID: https://orcid.org/0000-0001-5984-0395)
- Andrew Robertson (ORCID: https://orcid.org/0000-0002-0086-0524)
- Vladan Markov (ORCID: https://orcid.org/0000-0002-5694-6124)
- G. Desprez (ORCID: https://orcid.org/0000-0001-8325-1742)
- T. Schrabback (ORCID: https://orcid.org/0000-0002-6987-7834)
- Chris J. Willott (ORCID: https://orcid.org/0000-0002-4201-7367)
- Ghassan T. E. Sarrouh (ORCID: https://orcid.org/0000-0001-8830-2166)
- Yoshihisa Asada (ORCID: https://orcid.org/0000-0003-3983-5438)
- Roberta Tripodi (ORCID: https://orcid.org/0000-0002-9909-3491)
- Marcin Sawicki (ORCID: https://orcid.org/0000-0002-7712-7857)
- Maxim Markevitch (ORCID: https://orcid.org/0000-0003-0144-4052)
- Nicholas S. Martis (ORCID: https://orcid.org/0000-0003-3243-9969)
- Annika H. G. Peter (ORCID: https://orcid.org/0000-0002-8040-6785)
- Lamiya Mowla (ORCID: https://orcid.org/0000-0002-8530-9765)
- Douglas Clowe (ORCID: https://orcid.org/0000-0003-2416-1557)
- Anthony H. Gonzalez (ORCID: https://orcid.org/0000-0002-0933-8601)
- Gregor Rihtaršič (ORCID: https://orcid.org/0009-0009-4388-898X)
- B. C. Lemaux (ORCID: https://orcid.org/0000-0002-1428-7036)
- Jon Judež (ORCID: https://orcid.org/0009-0000-2101-1938)
- Giordano Felicioni (ORCID: https://orcid.org/0009-0001-0778-9038)
Institutions
- Herzberg Institute of Astrophysics (CA)
- Space Telescope Science Institute (US)
- Goddard Space Flight Center (US)
- University of Ljubljana (SI)
- University of Groningen (NL)
- Wellesley College (US)
- Universität Innsbruck (AT)
- York University (CA)
- Astronomical Observatory of Rome (IT)
- University of Florida (US)
- Gemini North Observatory (US)
- Ohio University (US)
- Université Bourgogne Franche-Comté (FR)
- Center for Astrophysics Harvard & Smithsonian (US)
- Carnegie Observatories (US)
- Institute for Fundamental Physics of the Universe (IT)
- The Ohio State University (US)
- Saint Mary's University (CA)
- University of California, Davis (US)
Publication Details
- Journal
- The Astrophysical Journal Letters
- Published
- 2025-12-19
- DOI
- https://doi.org/10.3847/2041-8213/ae27d2
- Primary Topic
- Galaxies: Formation, Evolution, Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.00