Galaxy Distances in the Nearby Universe: Corrections For Peculiar Motions

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24 pages including (9 eps figures and 7 tables). Figures 1,2,3,4 are available only upon request. Accepted by ApJ

Scientific paper

10.1086/306183

By correcting the redshift--dependent distances for peculiar motions through a number of peculiar velocity field models, we recover the true distances of a wide, all-sky sample of nearby galaxies (~ 6400 galaxies with velocities cz<5500 km/s), which is complete up to the blue magnitude B=14 mag. Relying on catalogs of galaxy groups, we treat ~2700 objects as members of galaxy groups and the remaining objects as field galaxies. We model the peculiar velocity field using: i) a cluster dipole reconstruction scheme; ii) a multi--attractor model fitted to the Mark II and Mark III catalogs of galaxy peculiar velocities. According to Mark III data the Great Attractor has a smaller influence on local dynamics than previously believed, whereas the Perseus-Pisces and Shapley superclusters acquire a specific dynamical role. Remarkably, the Shapley structure, which is found to account for nearly half the peculiar motion of the Local Group, is placed by Mark III data closer to the zone of avoidance with respect to its optical position. Our multi--attractor model based on Mark III data favors a cosmological density parameter Omega ~ 0.5 (irrespective of a biasing factor of order unity). Differences among distance estimates are less pronounced in the ~ 2000 - 4000 km/s distance range than at larger or smaller distances. In the last regions these differences have a serious impact on the 3D maps of the galaxy distribution and on the local galaxy density --- on small scales.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Galaxy Distances in the Nearby Universe: Corrections For Peculiar Motions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Galaxy Distances in the Nearby Universe: Corrections For Peculiar Motions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galaxy Distances in the Nearby Universe: Corrections For Peculiar Motions will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-142352

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.