Gary A. Wegner

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Observational parameters which can be used for redshift–independent distance determination using the Tully–Fisher (TF) technique are given for 782 spiral galaxies in the fields of 24 clusters or groups. I band photometry for the full sample was either obtained by us or compiled from published literature. Rotational velocities are derived either from 21 cm(More)
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(More)
Infrared I band photometry and velocity widths for galaxies in 24 clusters, with radial velocities between 1,000 and 10,000 km s−1 , are used to construct a template Tully–Fisher (TF) relation. The sources of scatter in the TF diagram are analyzed in detail; it is shown that the common practice of referring to a single figure of TF scatter is incorrect and(More)
The use of the Tully–Fisher (TF) relation for the determination of H◦ relies on the availability of an adequate template TF relation and of reliable primary distances. Here we use a TF template relation with the best available kinematical zero–point, obtained from a sample of 24 clusters of galaxies extending to cz ∼ 9, 000 km s , and the most recent set of(More)
Optical photometry is presented for the quadruple gravitational lens PG1115+080. A preliminary reduction of data taken from November 1995 to June 1996 gives component “C” leading component “B” by 23.7± 3.4 days and Department of Physics, Massachusetts Institute of Technology, Cambridge MA 02138 Department of Astronomy, Yale University, New Haven CT(More)
We use the recently completed redshift-distance survey of nearby early-type galaxies (ENEAR) to measure the dipole component of the peculiar velocity field to a depth of cz ∼ 6000 kms. The sample consists of 1145 galaxies brighter than mB = 14.5 and cz ≤ 7000 kms, uniformly distributed over the whole sky, and 129 fainter cluster galaxies within the same(More)
The Tully–Fisher (Tully & Fisher 1977; TF) relation is applied to obtain peculiar velocities of field spirals galaxies and to calculate dipoles of the peculiar velocity field to cz ' 8000 km s−1 . The field galaxy sample is spatially co–extensive with and completely independent on a cluster sample, for which dipole characteristics are given in a separate(More)
This is the second in a series of papers dedicated to unveil the mass structure and orbital content of a sample of flattened early-type galaxies in the Coma cluster. The ability of our orbit libraries to reconstruct internal stellar motions and the mass composition of a typical elliptical in the sample is investigated by means of Monte-Carlo simulations of(More)
Recently, peculiar velocity measurements became available for a new sample of galaxy clusters, hereafter the SCI sample. From an accurately calibrated Tully–Fisher relation for spiral galaxies, we compute the rms peculiar velocity, Vrms, and compare it to the linear theory predictions of COBE–normalized low–density and open CDM models (ΛCDM and OCDM,(More)
We present spectroscopic linestrength data for 4097 red-sequence galaxies in 93 low-redshift galaxy clusters, and use these to investigate variations in average stellar populations as a function of galaxy mass. Our analysis includes an improved treatment of nebular emission contamination, which affects ∼ 10% of the sample galaxies. Using the stellar(More)