The Rotation Velocity - Density Relation
نویسندگان
چکیده
We have assembled 21-cm linewidths for 376 of the 732 galaxies in a magnitudelimited redshift survey of the Perseus-Pisces region. We analyze a distance limited subset of 271 galaxies (131 widths) to examine the relationship between linewidth and local density. The sample indicates that galaxies with linewidths ∼> 480 km/s are absent from regions where the galaxy density is ∼< 0.03 galaxies Mpc−3 (MB(0) < −18.3). This effect is in the direction predicted by standard CDM models. Galaxies with linewidths ∼< 480 km/s appear throughout the sample. The observational constraints could be susbtantially improved with a larger sample, IR photometry, and more uniform 21-cm data.
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تاریخ انتشار 1996