Showing papers by "A. Gil de Paz published in 1999"
TL;DR: In this paper, Johnson B CCD photometry for the whole sample of galaxies of the UCM Survey Lists I and II was presented, and the new colour information was combined to search for clues on the properties of the galaxies, mainly by comparing our sample with other surveys.
Abstract: We present Johnson B CCD photometry for the whole sample of galaxies of the Universidad Complutense de Madrid (UCM) Survey Lists I and II. They constitute a well-defined and complete sample of galaxies in the Local Universe with active star formation. The data refer to 191 S0 to Irr galaxies at an averaged redshift of 0.027, and complement the already published Gunn r, J and K photometries. In this paper the observational and reduction features are discussed in detail, and the new colour information is combined to search for clues on the properties of the galaxies, mainly by comparing our sample with other surveys.
19 citations
TL;DR: In this paper, the velocity field of the blue compact dwarf galaxy Mrk 86 (NGC 2537) was studied using 14 long-slit optical spectra obtained in 10 different orientations and positions.
Abstract: We have studied the velocity field of the blue compact dwarf galaxy Mrk 86 (NGC 2537) using data provided by 14 long-slit optical spectra obtained in 10 different orientations and positions. This kinematical information is complemented with narrow-band ([O III]5007 A and Hα) and broad-band (B, V, Gunn r and K) imaging. The analysis of the galaxy global velocity field suggests that the ionized gas could be distributed in a rotating inclined disc, with projected central angular velocity of Ω=34 km s^−1 kpc^−1. The comparison between the stellar, H I and modelled dark matter density profile indicates that the total mass within its optical radius is dominated by the stellar component. Peculiarities observed in its velocity field can be explained by irregularities in the ionized gas distribution or local motions induced by star formation.
Kinematical evidences for two expanding bubbles, Mrk 86-B and Mrk 86-C, are given. They show expanding velocities of 34 and 17 km s^−1, Hα luminosities of 3×10^38 and 1.7×10^39 erg s^−1, and physical radii of 374 and 120 pc, respectively. The change in the [S II]/Hα, [N II]/Hα, [O II]/[O III] and [O III]/Hβ line ratios with the distance to the bubble precursor suggests a diminution in the ionization parameter and, in the case of Mrk 86-B, an enhancement of the shock-excited gas emission. The optical-near-infrared colours of the bubble precursors are characteristic of low-metallicity star-forming regions (∼0.2 Z_⊙) with burst strengths of about 1 per cent in mass.
12 citations
TL;DR: In this paper, the velocity field of the Blue Compact Dwarf galaxy Mrk86 (NGC2537) was studied using 14 long-slit optical spectra and the analysis of the global velocity field suggests that the ionized gas could be distributed in a rotating inclined disk, with projected central angular velocity of Omega=34 km/s/kpc.
Abstract: We have studied the velocity field of the Blue Compact Dwarf galaxy Mrk86 (NGC2537) using data provided by 14 long-slit optical spectra. This kinematical information is complemented with narrow-band ([OIII]5007A and Halpha) and broad-band (B, V, Gunn-r and K) imaging. The analysis of the galaxy global velocity field suggests that the ionized gas could be distributed in a rotating inclined disk, with projected central angular velocity of Omega=34 km/s/kpc. The comparison between the stellar, HI and modeled dark matter density profile, indicates that the total mass within its optical radius is dominated by the stellar component. Peculiarities observed in its velocity field can be explained by irregularities in the ionized gas distribution or local motions induced by star formation. Kinematical evidences for two expanding bubbles, Mrk86-B and Mrk86-C, are given. They show expanding velocities of 34 km/s and 17 km/s, Halpha luminosities of 3x10^38 erg/s and 1.7x10^39 erg/s, and physical radii of 374 and 120 pc, respectively. The change in the [SII]/Halpha, [NII]/Halpha, [OII]/[OIII] and [OIII]/Hbeta line ratios with the distance to the bubble precursor suggests a diminution in the ionization parameter and, in the case of Mrk86-B, an enhancement of the shock-excited gas emission. The optical-near-infrared colours of the bubble precursors are characteristic of low metallicity star forming regions (0.2 Zsun) with burst strengths of about 1 per cent in mass.
10 citations