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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Iii. The Stellar Population Gradients, D. Mehlert, D. Thomas, R. P. Saglia, R. Bender, G Wegner
Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Iii. The Stellar Population Gradients, D. Mehlert, D. Thomas, R. P. Saglia, R. Bender, G Wegner
Dartmouth Scholarship
Based on Paper I of this series (Mehlert et al. 2000), we derive central values and logarithmic gradients for the Hβ, Mg and Fe indices of 35 early-type galaxies in the Coma cluster. We find that pure elliptical galaxies have on average slightly higher velocity dispersions, lower Hβ, and higher metallic line-strengths than galaxies with disks (S0). The latter form two families, one comparable to the ellipticals and a second one with significantly higher Hβ, and weaker metallic lines. Our measured logarithmic gradients within the effective radius are ⟨△Mg b⟩ ≈ −0.037, ⟨△⟨Fe⟩⟩ ≈ −0.029, ⟨△Hβ⟩ ≈ +0.017 and ⟨△σ⟩ …
Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Ii. The Minor Axis Dataset, G. Wegner, E. M. Corsini, R. P. Saglia, R. Bender
Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Ii. The Minor Axis Dataset, G. Wegner, E. M. Corsini, R. P. Saglia, R. Bender
Dartmouth Scholarship
We present minor axis, offset major axis and one diagonal long slit spectra for 10 E and S0 galaxies of the Coma cluster drawn from a magnitude-limited sample studied before. We derive rotation curves, velocity dispersion profiles and the H3 and H4 coefficients of the Hermite decomposition of the line of sight velocity distribution. Moreover, we derive the line index profiles of Mg, Fe and Hβ line indices and assess their errors. The data will be used to construct dynamical models of the galaxies and study their stellar populations.
Spatially Resolved Spectroscopy Of Coma Cluster Early–Type Galaxies, D. Mehlert, R. P. Saglia, R. Bender, G. Wegner
Spatially Resolved Spectroscopy Of Coma Cluster Early–Type Galaxies, D. Mehlert, R. P. Saglia, R. Bender, G. Wegner
Dartmouth Scholarship
We present long slit spectra for a magnitude limited sample of 35 E and S0 galaxies of the Coma cluster. The high quality of the data allowed us to derive spatially resolved spectra for a substantial sample of Coma galaxies for the first time. From these spectra we obtained rota- tion curves, the velocity dispersion profiles and the H3 and H4 coefficients of the Hermite decomposition of the line of sight velocity distribution. Moreover, we derive the radial line index profiles of Mg, Fe and Hβ line indices out to R ≈ 1re − 3re with high signal-to-noise ratio. We …
Fundamental Plane Distances To Early-Type Field Galaxies In The South Equatorial Strip. I. The Spectroscopic Data, K. R. Müller, G. Wegner, S. Raychaudhury, W. Freudling
Fundamental Plane Distances To Early-Type Field Galaxies In The South Equatorial Strip. I. The Spectroscopic Data, K. R. Müller, G. Wegner, S. Raychaudhury, W. Freudling
Dartmouth Scholarship
Radial velocities and central velocity dispersions are derived for 238 E/S0 galaxies from medium-resolution spectroscopy. New spectroscopic data have been obtained as part of a study of the Fundamental Plane distances and peculiar motions of early-type galaxies in three selected directions of the South Equatorial Strip, undertaken in order to investigate the reality of large-scale streaming motion; results of this study have been reported in M\"uller $et$ $al.$ (1998). The new APM South Equatorial Strip Catalog (−17.5 < δ < +2.5) was used to select the sample of field galaxies in three directions: (1) 15h10 – 16h10; (2) 20h30 – 21h50; (3) 00h10 – 01h30. The spectra obtained have a median S/N per ̊A of 23, an in- strumental resolution (FWHM) of ∼ 4 ̊A, and the spectro- graph resolution (dispersion) is ∼ 100 km s−1. The Fourier cross-correlation method was used to derive the radial ve- locities and velocity dispersions. The velocity dispersions have been corrected for the size of the aperture and for the galaxy effective radius. Comparisons of the derived radial velocities with data from the literature show that our values are accurate to 40 km s−1. A comparison with results from Jørgensen et al. (1995) shows that the derived central velocity dispersion have an rms scatter of 0.036 in log σ. There is no offset relative to the velocity dispersions of Davies et al. (1987).