Measuring the Mean and Scatter of the X-ray Luminosity -- Optical Richness Relation for maxBCG Galaxy Clusters (open access)

Measuring the Mean and Scatter of the X-ray Luminosity -- Optical Richness Relation for maxBCG Galaxy Clusters

We interpret and model the statistical weak lensing measurements around 130,000 groups and clusters of galaxies in the Sloan Digital Sky Survey presented by Sheldon et al. (2007). We present non-parametric inversions of the 2D shear profiles to the mean 3D cluster density and mass profiles in bins of both optical richness and cluster i-band luminosity. Since the mean cluster density profile is proportional to the cluster-mass correlation function, the mean profile is spherically symmetric by the assumptions of large-scale homogeneity and isotropy. We correct the inferred 3D profiles for systematic effects, including non-linear shear and the fact that cluster halos are not all precisely centered on their brightest galaxies. We also model the measured cluster shear profile as a sum of contributions from the brightest central galaxy, the cluster dark matter halo, and neighboring halos. We infer the relations between mean cluster virial mass and optical richness and luminosity over two orders of magnitude in cluster mass; the virial mass at fixed richness or luminosity is determined with a precision of {approx} 13% including both statistical and systematic errors. We also constrain the halo concentration parameter and halo bias as a function of cluster mass; both are in good …
Date: October 2, 2007
Creator: Rykoff, E. S.; McKay, T. A.; Becker, M. A.; Evrard, A.; Johnston, D. E.; Koester, B. P. et al.
Object Type: Article
System: The UNT Digital Library
Acceptable Knowledge Summary Report for Mixed TRU Waste Streams: SR-W026-221F-HET-A through D (open access)

Acceptable Knowledge Summary Report for Mixed TRU Waste Streams: SR-W026-221F-HET-A through D

This document, along with referenced supporting documents provides a defensible and auditable record of acceptable knowledge for the heterogeneous debris mixed transuranic waste streams generated in the FB-Line after January 25, 1990 and before March 20, 1997.
Date: October 2, 2001
Creator: Lunsford, G.F.
Object Type: Report
System: The UNT Digital Library
Proceedings of the 23rd Seismic Research Symposium: Worldwide Monitoring of Nuclear Explosions (open access)

Proceedings of the 23rd Seismic Research Symposium: Worldwide Monitoring of Nuclear Explosions

These proceedings contain papers prepared for the 23rd Seismic Research Review: Worldwide Monitoring of Nuclear Explosions, held 2-5 October, 2001 in Jackson Hole, Wyoming. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Technical Applications Center (AFTAC), the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: October 2, 2001
Creator: Warren, N. Jill & Chavez, Francesca C.
Object Type: Article
System: The UNT Digital Library