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The H-alpha and Infrared Star Formation Rates for the Nearby Field Galaxy Survey

L. J. Kewley·M. J. Geller·R. A. Jansen·M. A. Dopita
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Abstract

We investigate the H-alpha and infrared star formation rate (SFR) diagnostics for galaxies in the Nearby Field Galaxy Survey (NFGS). For the 81 galaxies in our sample, we derive H-alpha fluxes (included here) from integrated spectra. There is a strong correlation between the ratio of far-infrared to optical luminosities L(FIR)/L(H-alpha) and the extinction E(B-V) measured with the Balmer decrement. Before reddening correction, the SFR(IR) and SFR(H-alpha) are related to each other by a power-law. Correction of the SFR(H-alpha) for extinction using the Balmer decrement and a classical reddening curve both reduces the scatter in the SFR(IR)-SFR(H-alpha) correlation and results in a much closer agreement (within ~10%) between the two SFR indicators. This SFR relationship spans 4 orders of magnitude and holds for all Hubble types with IRAS detections in the NFGS. A constant ratio between the SFR(IR) and SFR(H-alpha) for all Hubble types, including early types (S0-Sab), suggests that the IR emission in all of these objects results from a young stellar population.

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L. J. Kewley, M. J. Geller, R. A. Jansen, M. A. Dopita. 2002-09-14. The H-alpha and Infrared Star Formation Rates for the Nearby Field Galaxy Survey. https://doi.org/10.1086/344487

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