RT Journal Article T1 The current star-formation rate of the local universe A1 Gallego Maestro, Jesús A1 Zamorano Calvo, Jaime A1 Aragón Salamanca, A. A1 Rego Fernández, Manuel AB The Universidad Complutense de Madrid (UCM) survey is a long-term project aimed at finding and analyzing star-forming galaxies detected by their Hα emission in Schmidt objective-prism plates. The instrumental setup limits the volume of the universe surveyed to a redshift z ≲ 0.045. So far we have discovered several hundred emission-line galaxies (ELGs) undergoing star formation at a wide range of levels. Analyzing a complete sample of ELGs from the UCM survey, we have computed the Hα luminosity function for the star-forming galaxies in the surveyed volume of the universe. A Schechter function provides a good fit to the H_α luminosity function with the following parameters: α = -1.3 ± 0.2, L^*(H_α) = 10^42.15±0.08 ergs s^-1, and φ^* = 10^-3.2±0.2 Mpc^3 for H_0 = 50 km s^-1 Mpc^-1. Integrating over the full range of luminosities, we obtain an H_α luminosity density of 10^39.1±0.2 ergs s^-1 Mpc^-3. Using the H_α emission as a star formation rate (SFR) estimator, this translates into a SFR density for the local universe of 0.013_−0.005^+0.007 M_☉ yr^-1 Mpc^-3 in star-forming galaxies with EW(H_α + [N_II]) > 10 Å and z lesssim 0.045 for a Scalo initial mass function. This is the first observational determination of this quantity, which will provide a direct test of current galaxy formation and evolution models. PB American Astronomical Society SN 0004-637X YR 1995 FD 1995-12-10 LK https://hdl.handle.net/20.500.14352/59816 UL https://hdl.handle.net/20.500.14352/59816 LA eng NO Aragón Salamanca, A. 1995, in ASP Conf. Ser., Fresh Views on Elliptical Galaxies, ed. A. Buzzoni, A. Renzini, & A. Serrano (San Francisco: ASP), in pressBoroson, T. A., Salzer, J. J., & Trotter, A. 1993, ApJ, 412, 524 Broadhurst, T. J., Ellis, R. S., & Glazebrook, K. 1992, Nature, 355, 55 Bruzual, G., & Charlot, S. 1993, ApJ, 405, 538Cole, S., Aragón Salamanca, A., Frenk, C. S., Navarro, J., & Zepf, E. 1994, MNRAS, 271, 781Colless, M. 1995, in Wide Field Spectroscopy and the Distant Universe, ed. S. Maddox & A. Aragón Salamanca (Singapore: World Scientific), 263Ellis, R. S., Colless, M., Broadhurst, T. J., Heyl, J., & Glazebrook, K. 1995, MNRAS, submittedGallagher, J. S., Bushouse, H., & Hunter, D. A. 1989, AJ, 97, 700 Gallagher, J. S., & Gibson, S. J. 1993, in Panchromatic View of Galaxies, ed. G. Hensler, C. Theis, & J. S. Gallagher (Gif-sur-Yvette: Editions Frontières), 207Gallego, J. 1995, PASP, 107, 708Gallego, J., Zamorano, J., Rego, M., Alonso, O., & Vitores, A. G. 1995a, A&AS, in pressGallego, J., Zamorano, J., Rego, M., & Vitores, A. G. 1995b, ApJ, submitted Huchra, J. P., & Sargent, W. L. W. 1973, ApJ, 186, 433Kauffmann, G., White, S. D. M., & Guiderdoni, B. 1993, MNRAS, 264, 201 Kennicutt, R. C. 1983, ApJ, 272, 54———. 1992, ApJ, 388, 310Koo, D. C., & Kron, R. G. 1992, ARA&A, 30, 613Lilly, S. J., Tresse, L., Hammer, F., Crampton, D., & Le Fevre, O. 1995, ApJ, 455, 108Mobasher, B., Sharples, R. M., & Ellis, R. S. 1993, MNRAS, 263, 560 Rego, M., Cordero, M., Zamorano, J., & Gallego, J. 1993, AJ, 105, 427 Rego, M., Zamorano, J., & González Riestra, R. 1989, A&AS, 79, 443 Salzer, J. J. 1989, ApJ, 347, 152Scalo, J. M. 1986, Fundam. Cosmic Phys., 11, 1Schechter, P. 1976, ApJ, 203, 297Schmidt, M. 1968, ApJ, 151, 393Songaila, A., Cowie, L. L., Hu, E. M., & Gardner, J. P. 1994, ApJS, 94, 461 Vitores, A. G. 1995, PASP, 107, 404Vitores, A. G., Zamorano, J., Rego, M., Alonso, O., & Gallego, J. 1995a, A&AS, submitted———. 1995b, A&A, submittedZamorano, J., Gallego, J., Rego, M., Vitores, A. G., & Alonso, O. 1995, ApJS, submittedZamorano, J., Gallego, J., Rego, M., Vitores, A. G., González Riestra, R., & Rodríguez Caderot, G. 1994, ApJS, 95, 387Zamorano, J., Rego, M., Gallego, J., Vitores, A. G., & González Riestra, R. 1992, AJ, 104, 1000Zamorano, J., Rego, M., González Riestra, R., & Rodríguez, G. 1990, A&AS, 170, 353 NO © 1995. The American Astronomical Society. We thank S. White, A. G. Vitores, O. Alonso, J. Gorgas, and N. Cardiel for their many valuable comments. This work was supported in part by the Spanish Programa Sectorial de Promoción del Conocimiento under grant PB93-456. A. A. S. acknowledges generous financial support from the Royal Society. NO Programa Sectorial de Promoción del Conocimiento (MEC), España NO Royal Society DS Docta Complutense RD 16 jul 2024