Early Results from GLASS-JWST. XVII. Building the First Galaxies-Chapter 1. Star Formation Histories for 5 < z < 7 Galaxies
Abstract
The JWST observations of high-redshift galaxies are used to measure their star formation histories-the buildup of stellar mass in the earliest galaxies. Here we use a novel analysis program, SEDz*, to compare near-IR spectral energy distributions for galaxies with redshifts 5 < z < 7 to combinations of stellar population templates evolved from z = 12. We exploit NIRCam imaging in seven wide bands covering 1-5 μm taken in the context of the GLASS-JWST-ERS program and use SEDz* to solve for well-constrained star formation histories for 24 exemplary galaxies. In this first look, we find a variety of histories, from long, continuous star formation over 5 < z < 12 to short but intense starbursts, sometimes repeating, and, most commonly, contiguous mass buildup lasting ~0.5 Myr, possibly the seeds of today's typical M* galaxies.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2023
- DOI:
- 10.3847/2041-8213/ac9ebb
- arXiv:
- arXiv:2208.04292
- Bibcode:
- 2023ApJ...947L..27D
- Keywords:
-
- Galaxies;
- Galaxy evolution;
- High-redshift galaxies;
- 573;
- 594;
- 734;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- ApJL in press (accepted on October 30, 2022)