NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-20 T05:18:10 PDT
Help | Comment | NED Home

For refcode 2003ApJ...591..827P:
Retrieve 79 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2003ApJ...591..827P Spatial Analysis of the H{alpha} Emission in the Local Star-forming UCM Galaxies Pablo G. Perez-Gonzalez, Jaime Zamorano, Jesus Gallego, Alfonso Aragon-Salamanca, and Armando Gil de Paz Abstract. We present a photometric study of the H{alpha} emission in the Universidad Complutense de Madrid (UCM) Survey galaxies. This work complements our previously published spectroscopic data. We study the location of the star-forming knots, their intensity and concentration, and the relationship of these properties with those of the host galaxy. We also estimate that the amount of H{alpha} emission that arises from the diffuse ionized gas is about 15% -- 30% of the total H{alpha} flux for a typical UCM galaxy. This percentage seems to be independent of the Hubble type. Conversely, we find that an "average" UCM galaxy harbors a star formation event with 30% of its H{alpha} luminosity arising from a nuclear component. The implications of these results for higher redshift studies are discussed, including the effects of galaxy size and the depth of the observations. A correlation between the star formation rate and the Balmer decrement is observed, but such correlation breaks down for large values of the extinction. Finally, we recalculate the H{alpha} luminosity function and star formation rate density of the local universe using the new imaging data. Our results point out that, on average, spectroscopic observations detected about one-third of the total emission-line flux of a typical UCM galaxy. The new values obtained for the H{alpha} luminosity density and the star formation rate density of the local universe are 10^39.3+/-0.2^ ergs s^-1^ Mpc^-3^ and {rho}_SFR_=0.016^+0.007^_-0.004_ M_sun_ yr^-1^ Mpc^-3^ (H_0_=50 km s^-1^ Mpc^-1^, {OMEGA}_M_=1.0, {LAMBDA}=0). The corresponding values for the "concordance cosmology" (H_0_=70 km s^-1^ Mpc^-1^, {OMEGA}_M_=0.3, {LAMBDA}=0.7) are 10^39.5+/-0.2^ ergs s^-1^ Mpc^-3^ and {rho}_SFR_=0.029^+0.008^_-0.005_ M_sun_ yr^-1^ Mpc^-3^. Keywords: Galaxies: Dwarf, Galaxies: Evolution, Galaxies: Starburst, Stars: Formation
Retrieve 79 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home