Duration and properties of the embedded phase of star formation in 37 nearby galaxies from PHANGS-JWST
Light reprocessed by dust grains emitting in the infrared enables the study of the physics at play in dusty embedded regions, where ultraviolet and optical wavelengths are attenuated. Infrared telescopes such as JWST have made it possible to study the earliest feedback phases, when stars are shielded by cocoons of gas and dust. Comprehending this phase is crucial for unravelling the effects of feedback from young stars that leads to their emergence and the dispersal of their host molecular clouds. Here we show that the transition from the embedded to the exposed phase of star formation is short (< 4 Myr) and sometimes almost absent (< 1 Myr) across a sample of 37 nearby star-forming galaxies covering a wide range of morphologies, from massive barred spirals to irregular dwarfs. The short duration of the dust-clearing timescales suggests a predominant role of pre-supernova feedback mechanisms in revealing newborn stars, confirming previous results on smaller samples and allowing, for the first time, a statistical analysis of their dependencies. We find that the timescales associated with mid-infrared emission at 21 μm, tracing a dust-embedded feedback phase, are controlled by a complex interplay between giant molecular cloud properties (masses and velocity dispersions) and galaxy morphology. We report relatively longer durations of the embedded phase of star formation in barred spiral galaxies, while this phase is significantly reduced in low-mass irregular dwarf galaxies. We discuss tentative trends with gas-phase metallicity, which may favor faster cloud dispersal at low metallicities.
Authors
- Karin M. Sandstrom (ORCID: https://orcid.org/0000-0002-4378-8534)
- Justus Neumann (ORCID: https://orcid.org/0000-0002-3289-8914)
- David A. Thilker (ORCID: https://orcid.org/0000-0002-8528-7340)
- M. Boquien (ORCID: https://orcid.org/0000-0003-0946-6176)
- Debosmita Pathak (ORCID: https://orcid.org/0000-0003-2721-487X)
- Jaeyeon Kim (ORCID: https://orcid.org/0000-0002-0432-6847)
- Francesco Belfiore (ORCID: https://orcid.org/0000-0002-2545-5752)
- Mélanie Chevance (ORCID: https://orcid.org/0000-0002-5635-5180)
- Ryan Chown (ORCID: https://orcid.org/0000-0001-8241-7704)
- Lise Ramambason (ORCID: https://orcid.org/0000-0002-9190-9986)
- J. Eduardo Méndez-Delgado (ORCID: https://orcid.org/0000-0002-6972-6411)
- Hamid Hassani (ORCID: https://orcid.org/0000-0002-8806-6308)
- Lukas Neumann (ORCID: https://orcid.org/0000-0001-9793-6400)
- J. M. Diederik Kruijssen (ORCID: https://orcid.org/0000-0002-8804-0212)
- Thomas G. Williams (ORCID: https://orcid.org/0000-0002-0012-2142)
- Sumit K. Sarbadhicary (ORCID: https://orcid.org/0000-0002-4781-7291)
- Tony D. Weinbeck (ORCID: https://orcid.org/0009-0005-8923-558X)
- Kathryn Grasha (ORCID: https://orcid.org/0000-0002-3247-5321)
- Simon C. O. Glover (ORCID: https://orcid.org/0000-0001-6708-1317)
- Eva Schinnerer (ORCID: https://orcid.org/0000-0002-3933-7677)
- Jiayi Sun (ORCID: https://orcid.org/0000-0003-0378-4667)
- Bradley C. Whitmore (ORCID: https://orcid.org/0000-0002-3784-7032)
- V. Egorov (ORCID: https://orcid.org/0000-0002-7117-904X)
- A. Amiri (ORCID: https://orcid.org/0000-0002-8553-1964)
- Jessica Sutter (ORCID: https://orcid.org/0000-0002-9183-8102)
- Adam K. Leroy (ORCID: https://orcid.org/0000-0002-2545-1700)
- Hwihyun Kim (ORCID: https://orcid.org/0000-0003-4770-688X)
- Ivan S. Gerasimov (ORCID: https://orcid.org/0000-0001-7113-8152)
- Leonardo Úbeda (ORCID: https://orcid.org/0000-0001-7130-2880)
- Kathryn Kreckel (ORCID: https://orcid.org/0000-0001-6551-3091)
- Hsi-An Pan (ORCID: https://orcid.org/0000-0002-1370-6964)
- Simthembile Dlamini (ORCID: https://orcid.org/0000-0002-2885-6172)
- Daniel A. Dale (ORCID: https://orcid.org/0000-0002-5782-9093)
- Hannah Koziol (ORCID: https://orcid.org/0009-0001-5949-1524)
- Andrea Romanelli
Institutions
- Tamkang University (TW)
- Australian National University (AU)
- University of Wyoming (US)
- Space Telescope Science Institute (US)
- Whitman College (US)
- Johns Hopkins University (US)
- University of Alberta (CA)
- University of Cape Town (ZA)
- Princeton University (US)
- Université Côte d'Azur (FR)
- Heidelberg University (DE)
- Arcetri Astrophysical Observatory (IT)
- Laboratoire AstroParticule et Cosmologie (FR)
- University of Oxford (GB)
- Kavli Institute for Particle Astrophysics and Cosmology (US)
- Gemini North Observatory (US)
- Max Planck Institute for Astronomy (DE)
- Gemini South Observatory (CL)
- Observatoire de la Côte d’Azur (FR)
- ARC Centre of Excellence for All-sky Astrophysics (AU)
- The Ohio State University (US)
- Inter-University Centre for Astronomy and Astrophysics (IN)
- University of Arkansas at Fayetteville (US)
- Universidad Nacional Autónoma de México (MX)
- Netherlands Institute for Radio Astronomy (NL)
Publication Details
- Journal
- Astronomy and Astrophysics
- Published
- 2025-12-11
- DOI
- https://doi.org/10.1051/0004-6361/202556206
- Primary Topic
- Astrophysics and Star Formation Studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00