THE MOSDEF SURVEY: DISSECTING THE STAR FORMATION RATE VERSUS STELLAR MASS RELATION USING Hα AND Hβ EMISSION LINES AT z ∼ 2
- Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States)
- Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
- Astronomy Department, University of California, Berkeley, CA 94720 (United States)
- Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093 (United States)
We present results on the star formation rate (SFR) versus stellar mass (M{sub *}) relation (i.e., the “main sequence”) among star-forming galaxies at 1.37 ≤ z ≤ 2.61 using the MOSFIRE Deep Evolution Field (MOSDEF) survey. Based on a sample of 261 galaxies with Hα and Hβ spectroscopy, we have estimated robust dust-corrected instantaneous SFRs over a large range in M{sub *} (∼10{sup 9.5}–10{sup 11.5} M{sub ⊙}). We find a correlation between log(SFR(Hα)) and log(M{sub *}) with a slope of 0.65 ± 0.08 (0.58 ± 0.10) at 1.4 < z < 2.6 (2.1 < z < 2.6). We find that different assumptions for the dust correction, such as using the color excess of the stellar continuum to correct the nebular lines, sample selection biases against red star-forming galaxies, and not accounting for Balmer absorption, can yield steeper slopes of the log(SFR)–log(M{sub *}) relation. Our sample is immune from these biases as it is rest-frame optically selected, Hα and Hβ are corrected for Balmer absorption, and the Hα luminosity is dust corrected using the nebular color excess computed from the Balmer decrement. The scatter of the log(SFR(Hα))–log(M{sub *}) relation, after accounting for the measurement uncertainties, is 0.31 dex at 2.1 < z < 2.6, which is 0.05 dex larger than the scatter in log(SFR(UV))–log(M{sub *}). Based on comparisons to a simulated SFR–M{sub *} relation with some intrinsic scatter, we argue that in the absence of direct measurements of galaxy-to-galaxy variations in the attenuation/extinction curves and the initial mass function, one cannot use the difference in the scatter of the SFR(Hα)– and SFR(UV)–M{sub *} relations to constrain the stochasticity of star formation in high-redshift galaxies.
- OSTI ID:
- 22521766
- Journal Information:
- Astrophysical Journal, Vol. 815, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
The MOSFIRE Deep Evolution Field (MOSDEF) survey: Rest-frame optical spectroscopy for ∼1500 H-SELECTED GALAXIES AT 1.37⩽z⩽3.8
The MOSDEF Survey: Dynamical and baryonic masses and kinematic structures of star-forming galaxies AT 1.4 ≤ z ≤ 2.6