TY - JOUR
T1 - The MOSDEF survey
T2 - The dependence of H α-to-UV SFR ratios on SFR and size at z ∼2
AU - Fetherolf, Tara
AU - Reddy, Naveen A.
AU - Shapley, Alice E.
AU - Kriek, Mariska
AU - Siana, Brian
AU - Coil, Alison L.
AU - Mobasher, Bahram
AU - Freeman, William R.
AU - Sanders, Ryan L.
AU - Price, Sedona H.
AU - Shivaei, Irene
AU - Azadi, Mojegan
AU - de Groot, Laura
AU - Leung, Gene C.K.
AU - Zick, Tom O.
N1 - Publisher Copyright:
© 2021 The Author(s).
PY - 2021/11/1
Y1 - 2021/11/1
N2 - We perform an aperture-matched analysis of dust-corrected H α and UV star formation rates (SFRs) using 303 star-forming galaxies with spectroscopic redshifts 1.36 < zspec < 2.66 from the MOSFIRE Deep Evolution Field survey. By combining H α and H β emission line measurements with multiwaveband resolved Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey/3D-HST imaging, we directly compare dust-corrected H α and UV SFRs, inferred assuming a fixed attenuation curve shape and constant SFHs, within the spectroscopic aperture. Previous studies have found that H α and UV SFRs inferred with these assumptions generally agree for typical star-forming galaxies, but become increasingly discrepant for galaxies with higher SFRs (Z100 M⊙ yr-1), with H α-to-UV SFR ratios being larger for these galaxies. Our analysis shows that this trend persists even after carefully accounting for the apertures over which H α and UV-based SFRs (and the nebular and stellar continuum reddening) are derived. Furthermore, our results imply that H α SFRs may be higher in the centres of large galaxies (i.e. where there is coverage by the spectroscopic aperture) compared to their outskirts, which could be indicative of inside-out galaxy growth. Overall, we suggest that the persistent difference between nebular and stellar continuum reddening and high H α-to-UV SFR ratios at the centres of large galaxies may be indicative of a patchier distribution of dust in galaxies with high SFRs.
AB - We perform an aperture-matched analysis of dust-corrected H α and UV star formation rates (SFRs) using 303 star-forming galaxies with spectroscopic redshifts 1.36 < zspec < 2.66 from the MOSFIRE Deep Evolution Field survey. By combining H α and H β emission line measurements with multiwaveband resolved Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey/3D-HST imaging, we directly compare dust-corrected H α and UV SFRs, inferred assuming a fixed attenuation curve shape and constant SFHs, within the spectroscopic aperture. Previous studies have found that H α and UV SFRs inferred with these assumptions generally agree for typical star-forming galaxies, but become increasingly discrepant for galaxies with higher SFRs (Z100 M⊙ yr-1), with H α-to-UV SFR ratios being larger for these galaxies. Our analysis shows that this trend persists even after carefully accounting for the apertures over which H α and UV-based SFRs (and the nebular and stellar continuum reddening) are derived. Furthermore, our results imply that H α SFRs may be higher in the centres of large galaxies (i.e. where there is coverage by the spectroscopic aperture) compared to their outskirts, which could be indicative of inside-out galaxy growth. Overall, we suggest that the persistent difference between nebular and stellar continuum reddening and high H α-to-UV SFR ratios at the centres of large galaxies may be indicative of a patchier distribution of dust in galaxies with high SFRs.
KW - Galaxies: Evolution
KW - Galaxies: Fundamental parameters
KW - Galaxies: High-redshift
KW - Galaxies: Star formation
KW - Methods: Data analysis
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U2 - 10.1093/mnras/stab2570
DO - 10.1093/mnras/stab2570
M3 - Article
AN - SCOPUS:85118158254
SN - 0035-8711
VL - 508
SP - 1431
EP - 1445
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -