Another Look at the Abell Cluster Inertial Frame Bulk Flow

Abstract

view Abstract Citations (11) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Another Look at the Abell Cluster Inertial Frame Bulk Flow Graham, Alister W. Abstract Recently, use has been made of the relationship between absolute magnitude and galaxy structure for the first-ranked galaxies in Abell clusters out to 15,000 km s 1, in a determination of a large bulk flow for this volume (see the recent work of Lauer & Postman). The technique uses the logarithmic slope of the galaxy luminosity profile, at 10 h -1 kpc, parameterized by alpha, as an indicator of the galactic structure. In examining this M-alpha relation, it is shown to be similar to a magnitude-radius relation. Fitting a de Vaucouleurs R^{114 }law profile to the Abell brightest cluster galaxy (BCG) sample of Lauer & Postman, the M-log .t'e relationship is used to test for Local Group motion with respect to the Abell cluster inertial reference frame (ACIF), defined by the BCG. A motion of 459 + 371 km s 1 toward 1 = 2030, b = 290 (l 320) is obtained when using the entire sample of 119 BCGs. This differs from the Local Group velocity inferred by the cosmic microwave background dipole, implying that the ACIF has a bulk flow of 738 + 158 km s - I toward 1 = 3300, b = +450 (l 260). Both vectors are consistent with those derived by Lauer & Postman. The BCGs studied are shown to be a very homogeneous set of objects, with their radial size corrected magnitudes having a scatter of only 0.26 mag, making them a powerful tool in measuring galaxy distances and peculiar velocities. Using accurate CCD photometry, the galaxy light profiles are seen to be well fitted by an R^{1 4 }law. The slope of the mu -log re relation, for the BCG, is found to have a value of 2.87. Furthermore, there is negligible evidence for curvature in this bright portion of the fundamental plane. It is shown that use of the M-alpha relation is preferred over the M-log re relation in this type of analysis of bulk flow motion, as it results in considerably smaller error bars. Publication: The Astrophysical Journal Pub Date: March 1996 DOI: 10.1086/176866 Bibcode: 1996ApJ...459...27G Keywords: COSMOLOGY: OBSERVATIONS; GALAXIES: DISTANCES AND REDSHIFTS; GALAXIES: FUNDAMENTAL PARAMETERS; GALAXIES: PHOTOMETRY; COSMOLOGY: LARGE-SCALE STRUCTURE OF UNIVERSE full text sources ADS | data products NED (119) SIMBAD (118)