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arXiv · astro-ph/0107258

Star Formation in a Complete Spectroscopic Survey of Galaxies

B. J. Carter·D. G. Fabricant·M. J. Geller·M. J. Kurtz
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Abstract

The 15R-North galaxy redshift survey is a uniform spectroscopic survey (S/N $\sim $10) covering the range 3650---7400Åfor 3149 galaxies with median redshift 0.05. The sample is 90% complete to $R=15.4$. The median slit covering fraction is 24% of the galaxy, apparently sufficient to minimize the effects of aperture bias on the EW(H$α$). Forty-nine percent of the galaxes in the survey have one or more emission lines detected at $\geq 2 σ$. In agreement with previous surveys, the fraction of absorption-line galaxies increases steeply with galaxy luminosity. We use H$β$, O[III], H$α$, and [N\II] to discriminate between star-forming galaxies and AGNs. We use the EW(H$α$ + [N\II]) to estimate the Scalo birthrate parameter, $b$, the ratio of the current star formation rate to the time averaged star formation rate. Finally, we examine the way galaxies of different spectroscopic type trace the large-scale galaxy distribution.

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B. J. Carter, D. G. Fabricant, M. J. Geller, M. J. Kurtz. 2001-07-14. Star Formation in a Complete Spectroscopic Survey of Galaxies. https://doi.org/10.1086/322349

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