A Face-on Tully-Fisher Relation
We construct the first ``face-on'' Tully-Fisher (TF) relation for 24galaxies with inclinations between 16° and 41°. The enablingmeasurements are integral-field echelle spectroscopy from the WIYN 3.5 mtelescope, which yield accurate kinematic estimates of disk inclinationto ~15°. Kinematic inclinations are of sufficient accuracy that ourmeasured TF scatter of 0.42 mag is comparable to other surveys evenwithout internal absorption corrections. Three of four galaxies withsignificant kinematic and photometric asymmetries also have the largestdeviations from our TF relation, suggesting that asymmetries make animportant contribution to TF scatter. By measuring inclinations below40°, we establish a direct path to linking this scatter to theunprojected structure of disks and making nondegenerate dynamical massdecompositions of spiral galaxies.
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A Measurement of Disk Ellipticity in Nearby Spiral Galaxies
We have measured the intrinsic disk ellipticity for seven nearby, nearlyface-on spiral galaxies by combining Densepak integral-fieldspectroscopy with I-band imaging from the WIYN telescope. Initiallyassuming an axisymmetric model, we determine the kinematic inclinationsand position angles from Hα velocity fields and the photometricaxis ratios and position angles from imaging data. We interpret theobserved disparities between kinematic and photometric disk parametersin terms of an intrinsic nonzero ellipticity ɛ. The meanellipticity of our sample is 0.05. If the majority of disk galaxies havesuch intrinsic axis ratios, this would account for roughly 50% of thescatter in the Tully-Fisher relation. This result, in turn, placestighter constraints on other sources of scatter in this relation, themost astrophysically compelling of which is galaxy mass-to-light ratios.
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Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
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Groups of galaxies. III. Some empirical characteristics.
Not Available
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Preliminary results on the study of the environment of a complete sample of Seyfert galaxies:
Not Available
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Spectroscopy of Blue Compact Galaxies
Blue Compact Galaxies (BCGs) are gas--rich systems undergoing verymassive starburst events which involve the entire galaxy. We performed aspectroscopic study of 12 BCG in order to determine metallicities andhelium content. Some objects show presence of broadened emission lines,probably due to internal motion of the interstellar medium, caused byintense stellar winds and supernov explosions.
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The far-infrared properties of the CfA galaxy sample. I - The catalog
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
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Neutral hydrogen observations of galaxies in superclusters
Neutral hydrogen observations of spiral galaxies in the Uppsala GeneralCatalog were made with the 91 m telescope in Green Bank. Results of theH I observations are presented for 309 objects north of declination +38deg in the right ascension range between 10 h and 22 h and for a sampleof 46 objects just south of the equator in the region around R.A.between 0 h and 3 h. Many of these objects are outlying members ofsuperclusters and may be useful in the study of deviations from Hubbleflow on supercluster scales. Velocity widths as measured by fivedifferent algorithms are presented along with a profile quality index.
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A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
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