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Full-Text Articles in Physical Sciences and Mathematics
The Peculiar Motions Of Early-Type Galaxies In Two Distant Rregions — Ii. The Spectroscopic Data, Gary Wegner, Matthew Colless, R. P. Saglia, Robert K. Mcmahan
The Peculiar Motions Of Early-Type Galaxies In Two Distant Rregions — Ii. The Spectroscopic Data, Gary Wegner, Matthew Colless, R. P. Saglia, Robert K. Mcmahan
Dartmouth Scholarship
We present the spectroscopic data for the galaxies studied in the EFAR project, which is designed to measure the properties and peculiar motions of early-type galaxies in two distant regions. We have obtained 1319 spectra of 714 early-type galaxies over 33 observing runs on 10 different telescopes. We describe the observations and data reductions used to measure redshifts, velocity dispersions and the Mgb and Mg2 Lick linestrength indices. Detailed simulations and intercomparison of the large number of repeat observations lead to reliable error estimates for all quantities. The measurements from different observing runs are calibrated to a common …
The I-Band Tully-Fisher Relation For Sc Galaxies: 21 Centimeter H I Line Data, Martha P. Haynes, Riccardo Giovanelli, Pierre Chamaraux, Luiz N. Da Costa, Wolfram Freudling, John J. Salzer, Gary Wegner
The I-Band Tully-Fisher Relation For Sc Galaxies: 21 Centimeter H I Line Data, Martha P. Haynes, Riccardo Giovanelli, Pierre Chamaraux, Luiz N. Da Costa, Wolfram Freudling, John J. Salzer, Gary Wegner
Dartmouth Scholarship
A compilation of 21 cm line spectral parameters specifically designed for application of the Tully-Fisher (TF) distance method is presented for 1201 spiral galaxies, primarily field Sc galaxies, for which optical I-band photometric imaging is also available. New H I line spectra have been obtained for 881 galaxies. For an additional 320 galaxies, spectra available in a digital archive have been reexamined to allow application of a single algorithm for the derivation of the TF velocity width parameter. A velocity width algorithm is used that provides a robust measurement of rotational velocity and permits an estimate of the error …
The I-Band Tully-Fisher Relation For Sc Galaxies: Optical Imaging Data, Martha P. Haynes, Riccardo Giovanelli, John J. Salzer, Gary Wegner
The I-Band Tully-Fisher Relation For Sc Galaxies: Optical Imaging Data, Martha P. Haynes, Riccardo Giovanelli, John J. Salzer, Gary Wegner
Dartmouth Scholarship
Properties derived from the analysis of photometric I-band imaging observations are presented for 1727 inclined spiral galaxies, mostly of types Sbc and Sc. The reduction, parameter extraction, and error estimation procedures are discussed in detail. The asymptotic behavior of the magnitude curve of growth and the radial variation in ellipticity and position angle are used in combination with the linearity of the surface brightness falloff to fit the disk portion of the profile. Total I-band magnitudes are calculated by extrapolating the detected surface brightness profile to a radius of eight disk scale lengths. Errors in the magnitudes, typically …
The Peculiar Motions Of Early-Type Galaxies In Two Distant Regions -- V. The Mg-- Relation, Age And Metallicity, M. Colless, D. Burstein, R. L. Davies, R. K. Mcmahan, R. P. Saglia, G. Wegner
The Peculiar Motions Of Early-Type Galaxies In Two Distant Regions -- V. The Mg-- Relation, Age And Metallicity, M. Colless, D. Burstein, R. L. Davies, R. K. Mcmahan, R. P. Saglia, G. Wegner
Dartmouth Scholarship
We have examined the Mg—σ relation for early-type galaxies in the EFAR sample and its dependence on cluster properties. A comprehensive maximum likelihood treatment of the sample selection and measurement errors gives fits to the global Mg—σ relation of Mg b′=0.131 log σ −0.131 and Mg2=0.257 log σ −0.305. The slope of these relations is 25 per cent steeper than that obtained by most other authors owing to the reduced bias of our fitting method. The intrinsic scatter in the global Mg— σ relation is estimated to be 0.016 mag in Mg b′ and 0.023 …
Stellar Kinematics Of The Double Nucleus Of M31, Thomas S. Statler, Ivan R. King, Philippe Crane, Robert I. Jedrzejewski
Stellar Kinematics Of The Double Nucleus Of M31, Thomas S. Statler, Ivan R. King, Philippe Crane, Robert I. Jedrzejewski
Dartmouth Scholarship
We report observations of the double nucleus of M31 with the f/48 long-slit spectrograph of the Hubble Space Telescope Faint Object Camera. We obtain a total exposure of 19,000 s over seven orbits, with the 0063-wide slit along the line between the two brightness peaks (P.A. 42°). Careful correction of the raw data for detector backgrounds and geometric distortion is essential. A spectrum of Jupiter obtained with the same instrument is used as a spectral template to extract rotation and velocity dispersion profiles by cross-correlation. The rotation curve is resolved and reaches a maximum amplitude of ~250 km s-1 roughly …