| Autor: |
Vihang Mehta, Harry I. Teplitz, Claudia Scarlata, Xin Wang, Anahita Alavi, James Colbert, Marc Rafelski, Norman Grogin, Anton Koekemoer, Laura Prichard, Rogier Windhorst, Justin M. Barber, Christopher J. Conselice, Y. Sophia Dai, Jonathan P. Gardner, Eric Gawiser, Yicheng Guo, Nimish Hathi, Pablo Arrabal Haro, Matthew Hayes, Kartheik G. Iyer, Rolf A. Jansen, Zhiyuan Ji, Peter Kurczynski, Maxwell Kuschel, Ray A. Lucas, Kameswara Mantha, Robert W. O’Connell, Swara Ravindranath, Brant E. Robertson, Michael Rutkowski, Brian Siana, L. Y. Aaron Yung |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
The Astrophysical Journal, Vol 952, Iss 2, p 133 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1538-4357 |
| DOI: |
10.3847/1538-4357/acd9cf |
| Popis: |
The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) program provides Hubble Space Telescope (HST)/UVIS F275W imaging for four CANDELS fields. We combine this UV imaging with existing HST/near-IR grism spectroscopy from 3D-HST+AGHAST to directly compare the resolved rest-frame UV and H α emission for a sample of 979 galaxies at 0.7 < z < 1.5, spanning a range in stellar mass of 10 ^8−11.5 M _⊙ . Using a stacking analysis, we perform a resolved comparison between homogenized maps of rest-UV and H α to compute the average UV-to-H α luminosity ratio (an indicator of burstiness in star formation) as a function of galactocentric radius. We find that galaxies below stellar mass of ∼10 ^9.5 M _⊙ , at all radii, have a UV-to-H α ratio higher than the equilibrium value expected from constant star formation, indicating a significant contribution from bursty star formation. Even for galaxies with stellar mass ≳10 ^9.5 M _⊙ , the UV-to-H α ratio is elevated toward their outskirts ( R / R _eff > 1.5), suggesting that bursty star formation is likely prevalent in the outskirts of even the most massive galaxies, but is likely overshadowed by their brighter cores. Furthermore, we present the UV-to-H α ratio as a function of galaxy surface brightness, a proxy for stellar mass surface density, and find that regions below ∼10 ^7.5 M _⊙ kpc ^−2 are consistent with bursty star formation, regardless of their galaxy stellar mass, potentially suggesting that local star formation is independent of global galaxy properties at the smallest scales. Last, we find galaxies at z > 1.1 to have bursty star formation, regardless of radius or surface brightness. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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