Cosmological Parameters from the Comparison of the 2MASS Gravity Field with Peculiar Velocity Surveys

We compare the peculiar velocity field within 65 $h^{-1}$ Mpc predicted from 2MASS photometry and public redshift data to three independent peculiar velocity surveys based on type Ia supernovae, surface brightness fluctuations in ellipticals, and Tully-Fisher distances to spirals. The three peculiar velocity samples are each in good agreement with the predicted velocities and produce consistent results for \beta_{K}=\Omega\sbr{m}^{0.6}/b_{K}. Taken together the best fit $\beta_{K} = 0.49 \pm 0.04$. We explore the effects of morphology on the determination of $\beta$ by splitting the 2MASS sample into E+S0 and S+Irr density fields and find both samples are equally good tracers of the underlying dark matter distribution, but that early-types are more clustered by a relative factor b\sbr{E}/b\sbr{S} \sim 1.6. The density fluctuations of 2MASS galaxies in $8 h^{-1}$ Mpc spheres in the local volume is found to be \sigma\sbr{8,K} = 0.9. From this result and our value of $\beta_{K}$, we find \sigma_8 (\Omega\sbr{m}/0.3)^{0.6} = 0.91\pm0.12. This is in excellent agreement with results from the IRAS redshift surveys, as well as other cosmological probes. Combining the 2MASS and IRAS peculiar velocity results yields \sigma_8 (\Omega\sbr{m}^/0.3)^{0.6} = 0.85\pm0.05.Comment: 11 pages, ApJ accepte

A Test for Large-Scale Systematic Errors in Maps of Galactic Reddening

Accurate maps of Galactic reddening are important for a number of applications, such as mapping the peculiar velocity field in the nearby Universe. Of particular concern are systematic errors which vary slowly as a function of position on the sky, as these would induce spurious bulk flow. We have compared the reddenings of Burstein & Heiles (BH) and those of Schlegel, Finkbeiner & Davis (SFD) to independent estimates of the reddening, for Galactic latitudes |b| > 10. Our primary source of Galactic reddening estimates comes from comparing the difference between the observed B-V colors of early-type galaxies, and the predicted B-V color determined from the B-V--Mg_2 relation. We have fitted a dipole to the residuals in order to look for large-scale systematic deviations. There is marginal evidence for a dipolar residual in the comparison between the SFD maps and the observed early-type galaxy reddenings. If this is due to an error in the SFD maps, then it can be corrected with a small (13%) multiplicative dipole term. We argue, however, that this difference is more likely to be due to a small (0.01 mag.) systematic error in the measured B-V colors of the early-type galaxies. This interpretation is supported by a smaller, independent data set (globular cluster and RR Lyrae stars), which yields a result inconsistent with the early-type galaxy residual dipole. BH reddenings are found to have no significant systematic residuals, apart from the known problem in the region 230 < l < 310, -20 < b < 20.Comment: 8 pages, PASP, in press (Jan 1999

Workplaces in the cinema

Purpose – The purpose of this paper is to explore the representation of workplaces in the cinema and discuss its relevance to facilities management research. Design/methodology/approach – An analysis of representation of work and the workplace in three films is made. These are Metropolis (1927), Wall Street (1987) and Clerks (1994). Cross-case themes are then discussed. Findings – Although the three films are of different time periods and genres a number of common themes emerge. These include level of control over the work process, alienation from the product of work and social capital gained. This may have implications for how workplaces are perceived and interpreted. Analysis of representations of the workplace in popular culture may contribute to user-centred approaches to facilities management. Research limitations/implications – The study is limited to three films. A different choice might produce different results. Practical implications – Understanding representations of the workplace in popular culture may give insights into user responses to management actions. Originality/value – Although there is a research literature on the analysis of popular culture within organizational studies this has not been taken up by facilities management researchers. This paper explores the relevance of the analysis of an aspect of popular culture for facilities management

The Peculiar Velocities of Local Type Ia Supernovae and their Impact on Cosmology

We quantify the effect of supernova Type Ia peculiar velocities on the derivation of cosmological parameters. The published distant and local Ia SNe used for the Supernova Legacy Survey first-year cosmology report form the sample for this study. While previous work has assumed that the local SNe are at rest in the CMB frame (the No Flow assumption), we test this assumption by applying peculiar velocity corrections to the local SNe using three different flow models. The models are based on the IRAS PSCz galaxy redshift survey, have varying beta = Omega_m^0.6/b, and reproduce the Local Group motion in the CMB frame. These datasets are then fit for w, Omega_m, and Omega_Lambda using flatness or LambdaCDM and a BAO prior. The chi^2 statistic is used to examine the effect of the velocity corrections on the quality of the fits. The most favored model is the beta=0.5 model, which produces a fit significantly better than the No Flow assumption, consistent with previous peculiar velocity studies. By comparing the No Flow assumption with the favored models we derive the largest potential systematic error in w caused by ignoring peculiar velocities to be Delta w = +0.04. For Omega_Lambda, the potential error is Delta Omega_Lambda = -0.04 and for Omega_m, the potential error is Delta Omega_m < +0.01. The favored flow model (beta=0.5) produces the following cosmological parameters: w = -1.08 (+0.09,-0.08), Omega_m = 0.27 (+0.02,-0.02) assuming a flat cosmology, and Omega_Lambda = 0.80 (+0.08,-0.07) and Omega_m = 0.27 (+0.02,-0.02) for a w = -1 (LambdaCDM) cosmology.Comment: 4 pages, 2 figures, 1 table, accepted for publication in ApJ Letter

Aid Volatility, Policy and Development

We build on Bulir and Hamann's analysis of aid volatility (2003, 2005), showing that the conclusions reached depend on the dataset used. Their argument that the poorest countries have the highest volatility appears not to be correct. The impact of volatility on growth is negative overall, but differs between positive and negative volatility. The mix between `responsive´ components of aid, e.g. programme aid, and `proactive´ components, e.g. technical assistance, is important. Finally, we conclude that measures which increase trust between donor and recipient, and reductions in the degree of donor `oligopoly´, reduce aid volatility without obviously reducing its effectiveness

Spatial nucleation and crystal growth Final report, 1 Jun. 1964 - 30 Sep. 1967

Nucleation and growth processes in interstellar grain formatio