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The interpretation of observations of distant galaxy samples is limited
by our partial knowledge of the spectrophotometric properties of the
local field galaxy population. In particular, the range in properties
as a function of galaxy luminosity has not been studied systematically.
To remedy this situation, optical spectrophotometric and photometric
observations were obtained for 196 nearby galaxies that form a
representative sample of the local field population. These galaxies
span the entire Hubble sequence in morphological type, as well as a wide
range of luminosities and colors.
In this thesis, the galaxy selection, the observations and data
reduction are described, and two atlases of the primary data products
are presented: one of the images and radial profiles of surface
brightness and color, the other of the nuclear and integrated spectra.
Furthermore, the first results of a study of the spectrophotometric
properties of the sample are discussed, focusing on the use of [O
II] as a tracer of star formation and on quantitative
measurements of galaxy morphology. The spectrophotometric database is
anticipated to be useful as a benchmark for studies of galaxies at both
low and high redshifts.
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HE commissioning of a new generation of large
aperture telescopes and recent advances in instrumentation have resulted
in a flood of spectroscopic, photometric, and morphological data on
faint and distant galaxies. Where previously only the brightest objects
could be observed in detail, now distant galaxies are routinely sampled
well down the galaxy luminosity function. The purpose of this
observational drive to reach farther and fainter has been either the
derivation of the parameters of the cosmological world model, or the
detection of the formation and subsequent evolution of galaxies.
In the past decade deeper and higher
resolution observations of the intermediate and high redshift universe
have produced many surprising discoveries (see Ellis 1997 for a
comprehensive review). These include (1) the large excess of faint blue
galaxies compared to expectations (Broadhurst et al. 1988;
Colless et al.1990), (2) moderate to strong luminosity
evolution (Odewahn et al. 1996; Ellis et al. 1996;
Lilly et al. 1995) which is morphologically segregated (Hammer
et al. 1997; Driver et al. 1998), and (3) evolution of
galaxy morphologies as evident from, e.g., the decline of
barred spiral galaxies with redshift (Abraham et al. 1996), the
increased rate of galaxy mergers (Glazebrook et al. 1995;
Abraham et al. 1996; van Dokkum et al. 1999), and the
appearance of ``chain galaxies'', very compact star forming galaxies and
other apparently proto-galactic systems (Cowie, Hu & Songaila 1995;
Steidel et al. 1996). At redshifts z 3 recent observations indicate a
prevalence of small, proto-galactic, actively star forming systems
(e.g., Stern & Spinrad 1999; Franx et al. 1997;
Dey et al. 1998; Weymann et al. 1998; Spinrad et
al. 1998; Chen, Lanzetta & Pascarelle 1999; van Breugel et
al. 1999; Hu, McMahon, & Cowie 1999). The combined star
formation rate in the universe appears to peak near a redshift of one,
although the data do not exclude a constant high rate of star formation
until z~1 and a steep decline ever since (Madau et al.
1996; Madau, Pozzetti & Dickinson 1998).
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