| Autor: |
Harshan, Anishya, Bradač, Maruša, Abraham, Roberto, Asada, Yoshihisa, Brammer, Gabriel, Desprez, Guillaume, Iyer, Karthiek, Martis, Nicholas S, Matharu, Jasleen, Mowla, Lamiya, Muzzin, Adam, Noirot, Gaël, Rihtaršič, Gregor, Sarrouh, Ghassan T E, Sawicki, Marcin, Strait, Victoria, Willott, Chris J |
| Předmět: |
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| Zdroj: |
Monthly Notices of the Royal Astronomical Society; 7/25/2024, Vol. 532 Issue 1, p1112-1125, 14p |
| Abstrakt: |
The epoch of reionization (EoR) progressed through the emission of ionizing photons from galaxies to their local intergalactic medium. In this work, we characterize the dwarf star-forming galaxies as candidates for the source of ionizing photons that drove EoR. We investigate the ionizing properties and star formation histories of star-forming dwarf galaxies at the last stages of EoR at |$4.8\lt z \lt 7$| using observations from the CAnadian NIRISS Unbiased Cluster Survey (CANUCS). The magnification due to gravitational lensing allows us to probe large dynamic ranges in stellar mass (|$2\times 10^{6}\le {M}_*/{\rm M}_\odot \le 5\times 10^{9}$|) and ultraviolet (UV) magnitudes (|$-22.68\le M_{\rm UV}\le =-15.95$|). We find a median UV slope |$\beta _{1500}\,$| of |$-2. 56\pm 0.23$| and the production efficiency of ionizing photons |$\log$| |$\xi _{\rm {ion}}\,$| |$=25.39\pm 0.6$| for the full sample (|$4.8\lt z \lt 7$|) with a median stellar mass of |$6.3\pm 0.5\times 10^{7} \, {\rm M}_\odot$|. We find both |$\beta _{1500}\,$| and |$\xi _{\rm {ion}}\,$| are marginally correlated with the stellar mass of the galaxy, indicating a possible greater contribution of dwarf galaxies to the reionization of the Universe. We find that on average, galaxies in our sample are experiencing a recent rise/burst of star formation which translates to a higher scatter in |$\xi _{\rm {ion}}\,$| and a large scatter in H |$\alpha$| equivalent widths (EWs). Finally, we investigate the trends of H |$\alpha$| and [O iii ] + H |$\beta$| EWs with UV magnitude and find |$M_{\rm UV}$| is correlated between H |$\alpha$| but not with [O iii ] + H |$\beta$| EWs indicating low metallicities and recent burst in the UV faint galaxies. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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