Volume-limited Galaxy Sample Research Articles

A ROSAT study of the cores of clusters of galaxies -- I. Cooling flows in an X-ray flux-limited sample

This is the first part of a study of the detailed X-ray properties of the cores of nearby clusters. We have used the flux-limited sample of 55 clusters of Edge et al. (1990) and archival and proprietary data from the {\it ROSAT} observatory. In this paper an X-ray spatial analysis based on the surface-brightness-deprojection technique is applied to the clusters in the sample with the aim of studying their cooling flow properties. We determine the fraction of cooling flows in this sample to be 70-90 percent and estimate the contribution of the flow region to the cluster X-ray luminosity. We show that the luminosity within a strong cooling flow can account for up to 70 percent of a cluster X-ray bolometric luminosity. Our analysis indicates that about 40 percent of the clusters in the sample have flows depositing more than 100 \Msunpyr throughout the cooling region and that these possibly have been undisturbed for many Gyr, confirming that cooling flows are the natural state of cluster cores. New cooling flows in the sample are presented and previously ambiguous ones are clarified. We have constructed a catalogue of some intracluster medium properties for the clusters in this sample. The profiles of the mass deposited from cooling flows are analyzed and evidence presented for the existence of breaks in some of the profiles. Comparison is made to recent optical and radio data. We cross-correlate our sample with the Green Bank, NVSS and FIRST surveys and to the volume-limited sample of brightest cluster galaxies presented by Lauer and Postman (1994). Although weak trends exist, no strong correlation between optical magnitude or radio power of the brightest cluster galaxy and the strength of the flow is found.

A volume-limited sample of IRAS galaxies to 4000 km/s, 3: CCD photometry from Palomar and Tololo observatories

view Abstract Citations (17) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Volume-Limited Sample of IRAS Galaxies to 4000 km/s. III. CCD Photometry From Palomar and Tololo Observatories Roth, Joshua Abstract An all-sky, quasi-volume-limited sample of 251 spiral galaxies within 4000 km s^-1^ has been extracted from the redshift survey of IRAS galaxies by Strauss et al. [ApJS, 83, 29 (1992)]. Distance moduli for these objects estimated via the Tully-Fisher (TF) method allow the peculiar velocity field and the cosmological density parameter to be constrained within this volume. The TF relation we exploit relates deprojected neutral hydrogen line width to near-infrared luminosity. Herein we present I and V band photometry for 159 members of this sample obtained with CCD cameras at Palomar and Tololo observatories. Image processing and photometric calibration procedures are described. Twenty seven objects with multiple calibrated observations suggest that isophotal I band magnitudes are reproduced to <~ 0.05 mag precision at {SIGMA}_I_ = 23.5 mag arcsec^-2^, and that systematic run-to-run offsets are limited to <~ 0.05 I mag. Publication: The Astronomical Journal Pub Date: September 1994 DOI: 10.1086/117118 Bibcode: 1994AJ....108..862R Keywords: Astronomical Photometry; Charge Coupled Devices; Galaxies; Hydrogen; Infrared Astronomy; Infrared Astronomy Satellite; Infrared Photometry; Line Spectra; Near Infrared Radiation; Red Shift; Sky Surveys (Astronomy); Calibrating; Distance; Image Processing; Infrared Imagery; Luminosity; Mass; Samples; Tables (Data); Velocity; Astronomy; GALAXIES: SPIRAL; DISTANCE SCALES; COSMOLOGY: OBSERVATIONS full text sources ADS | data products NED (158) SIMBAD (153) Related Materials (2) Part 1: 1991AJ....102.1303R Part 2: 1994AJ....108..851R

A volume-limited sample of IRAS galaxies to 4000 km/s, 2: Neutral hydrogen observations from the Parkes telescope

A volume-limited sample of IRAS galaxies to 4000 km/s, 2: Neutral hydrogen observations from the Parkes telescope

A volume-limited sample of IRAS galaxies to 4000 km/s. I - Neutral hydrogen observations from Jodrell Bank

view Abstract Citations (15) References (24) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A volume-limited sample of IRAS galaxies to 4000 kms-1 . I. Neutral hydrogen observations from Jodrell Bank. Roth, Joshua ; Mould, Jeremy R. ; Davies, Rodney D. Abstract A volume-limited catalog is constructed of normal spiral galaxies within the redshift interval 0-4000 km/s and brighter than 1.9 Jy at 60 microns to study relationships between fundamental galaxy properties and to map to the peculiar velocity field. Observations of 57 galazies are reported from this sample at Jodrell Bank, 42 of which resulted in detections, and study relationships between far-IR and neutral hydrogen properties. Gas and dynamical or halo mass are well correlated with each other and moderately so with far IR luminosity. A decrease in dynamical mass with increasing far-color temperature suggests that less massive, later-type systems enjoy higher specific star-formation rates. Publication: The Astronomical Journal Pub Date: October 1991 DOI: 10.1086/115956 Bibcode: 1991AJ....102.1303R Keywords: Galaxies; H Lines; Infrared Astronomy Satellite; Red Shift; Spiral Galaxies; Star Formation; Astrophysics full text sources ADS | data products SIMBAD (57) NED (57) Related Materials (2) Part 2: 1994AJ....108..851R Part 3: 1994AJ....108..862R