The ALMA REBELS Survey: Specific Star-Formation Rates in the Reionization Era

Autor: Michael W Topping, Daniel P Stark, Ryan Endsley, Rychard J Bouwens, Sander Schouws, Renske Smit, Mauro Stefanon, Hanae Inami, Rebecca A A Bowler, Pascal Oesch, Valentino Gonzalez, Pratika Dayal, Elisabete da Cunha, Hiddo Algera, Paul van der Werf, Andrea Pallottini, Laia Barrufet, Raffaella Schneider, Ilse De Looze, Laura Sommovigo, Lily Whitler, Luca Graziani, Yoshinobu Fudamoto, Andrea Ferrara
Přispěvatelé: Topping, M. W., Stark, D. P., Endsley, R., Bouwens, R. J., Schouws, S., Smit, R., Stefanon, M., Inami, H., Bowler, R. A. A., Oesch, P., Gonzalez, V., Dayal, P., da Cunha, E., Algera, H., van der Werf, P., Pallottini, A., Barrufet, L., Schneider, R., De Looze, I., Sommovigo, L., Whitler, L., Graziani, L., Fudamoto, Y., Ferrara, A., Astronomy
Rok vydání: 2022
Předmět:
Zdroj: Topping, M W, Stark, D P, Endsley, R, Bouwens, R J, Schouws, S, Smit, R, Stefanon, M, Inami, H, Bowler, R A A, Oesch, P, Gonzalez, V, Dayal, P, da Cunha, E, Algera, H, van Der Werf, P, Pallottini, A, Barrufet, L, Schneider, R, De Looze, I, Sommovigo, L, Whitler, L, Graziani, L, Fudamoto, Y & Ferrara, A 2022, ' The ALMA REBELS Survey : specific star formation rates in the reionization era ', Monthly Notices of the Royal Astronomical Society, vol. 516, no. 1, pp. 975-991 . https://doi.org/10.1093/mnras/stac2291
Monthly Notices of the Royal Astronomical Society, 516(1), 975-991
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Monthly Notices of the Royal Astronomical Society, 516(1), 975-991. Oxford University Press
ISSN: 0035-8711
1365-2966
DOI: 10.48550/arxiv.2203.07392
Popis: We present specific star-formation rates for 40 UV-bright galaxies at $z\sim7-8$ observed as part of the Reionization Era Bright Emission Line Survey (REBELS) ALMA large program. The sSFRs are derived using improved measures of SFR and stellar masses, made possible by measurements of far-infrared (FIR) continuum emission and [CII]-based spectroscopic redshifts. For each source in the sample, we derive stellar masses from SED fitting and total SFRs from calibrations of the UV and FIR emission. The median sSFR is $18_{-5}^{+7}$ Gyr$^{-1}$, significantly larger than literature measurements lacking constraints in the FIR. The increase in sSFR reflects the larger obscured SFRs we derive from the dust continuum relative to that implied by the UV+optical SED. We suggest that such differences may reflect spatial variations in dust across these luminous galaxies, with the component dominating the FIR distinct from that dominating the UV. We demonstrate that the inferred stellar masses (and hence sSFRs) are strongly-dependent on the assumed star formation history (SFH) in reionization-era galaxies. When large sSFR galaxies are modeled with non-parametric SFHs, the derived stellar masses can increase by an order of magnitude relative to constant star formation models, owing to the presence of a significant old stellar population that is outshined by the recent burst. The [CII] line widths in the largest sSFR systems are often very broad, suggesting dynamical masses that are easily able to accommodate the dominant old stellar population suggested by non-parametric models. Regardless of these systematic uncertainties in the derived parameters, we find that the sSFR increases rapidly toward higher redshifts for massive galaxies ($9.6
18 pages, 10 figures, submitted to MNRAS
Databáze: OpenAIRE
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