149 research outputs found
The Power Spectrum of the PSC Redshift Survey
We measure the redshift-space power spectrum P(k) for the recently completed
IRAS Point Source Catalogue (PSC) redshift survey, which contains 14500
galaxies over 84% of the sky with 60 micron flux >= 0.6 Jansky. Comparison with
simulations shows that our estimated errors on P(k) are realistic, and that
systematic errors due to the finite survey volume are small for wavenumbers k
>~ 0.03 h Mpc^-1. At large scales our power spectrum is intermediate between
those of the earlier QDOT and 1.2 Jansky surveys, but with considerably smaller
error bars; it falls slightly more steeply to smaller scales. We have fitted
families of CDM-like models using the Peacock-Dodds formula for non-linear
evolution; the results are somewhat sensitive to the assumed small-scale
velocity dispersion \sigma_V. Assuming a realistic \sigma_V \approx 300 km/s
yields a shape parameter \Gamma ~ 0.25 and normalisation b \sigma_8 ~ 0.75; if
\sigma_V is as high as 600 km/s then \Gamma = 0.5 is only marginally excluded.
There is little evidence for any `preferred scale' in the power spectrum or
non-Gaussian behaviour in the distribution of large-scale power.Comment: Latex, uses mn.sty, 14 pages including 11 Postscript figures.
Accepted by MNRA
Density and Velocity Fields from the PSCz Survey
We present the results for the predicted density and peculiar velocity fields
and the dipole from the PSCz survey of 15,000 IRAS galaxies over 84% of the
sky. We find a significant component to the dipole arising between 6000 and
15,000 km/s, but no significant component from greater distances. The
misalignment with the CMB is 20 degrees. The most remarkable feature of the
PSCz model velocity field is a coherent large-scale flow along the baseline
connecting Perseus-Pisces, the Local Supercluster, Great Attractor and the
Shapley Concentration. We have measured the parameter beta using the amplitude
of the dipole, bulk flow and point by point comparisons between the individual
velocities of galaxies in the MarkIII and SFI datasets, and the large-scale
clustering distortion in redshift space.All our results are consistent with
beta = 0.6 +- 0.1.Comment: 8 pages, 8 figures. To appear in 'Towards an Understanding of Cosmic
Flows', Victoria, July 1999, eds Courteau,S., Strauss,M., Willick,J. PAS
CERNBox: Storage gateway for CERN and beyond
The CERN IT Storage group ensures the coherent design, development, operation and evolution of storage and data management services at CERN for all aspects of physics, user and project data and general needs of the Laboratory. CERNBox is one of the services that actively contributes to this objective.
CERNBox is a cloud collaboration platform providing storage space (18PB) to users (37K accounts), projects (1.1K) and to LHC experiments (ATLAS, CMS, LHCb, ALICE) and other smaller experiments (33). We present the evolution of the platform from its humble origins 10 years ago and how the HEP landscape has influenced the expansion of the service to continue satisfying the ever growing demand of our users. We describe the challenges and opportunities presented by integrating a sync and share solution (ownCloud) with CERNâs custodial storage solution (EOS) and how this stack boosted a coherent integration with analysis farms (LXBATCH), Linux (LXPLUS) and Windows (TS) interactive clusters and Web analysis facilities (SWAN). We then turn to the part CERNBox has played in consolidation efforts in the IT department (DFS, AFS) and in providing end-users with a portfolio of applications (ROOT, CAD, MS365) while guaranteeing a maximum level of privacy.
We conclude by presenting the future of the service with its heterogeneous storage federation capabilities (EOSHOMEs, EOSPROJECTs, EOSATLAS, CEPHFS) and WLCG transfer mechanisms (WebDAV TPC)
Changing home and workplace in Victorian London : the life of Henry Jaques shirtmaker.
The paper uses unusually rich evidence from a manuscript life history written in 1901 from personal diaries to explore the changing relationship between home and workplace in Victorian London. The life history of Henry Jaques demonstrates the way in which decisions about employment and residence were related both to each other and to stages of the family life course. The uncertainty of work, lack of income to support a growing family, rising aspirations, the constant threat of illness, the ease of moving between rented property, close ties between home and workplace, the stresses produced by home working, and the attractions of suburbanization all interacted to shape the residential and employment history of Jaques and his family. The themes exemplified by this detailed life history were also relevant to many other people. Evidence collected from a large-scale project on lifetime residential histories is used to place the experiences of Henry Jaques in a broader context, and to show how they related to the changing social and economic structure of Victorian London
Changes in the number of new takeaway food outlets associated with adoption of management zones around schools: A natural experimental evaluation in England
© 2024 The Author(s). Published by Elsevier Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/By the end of 2017, 35 local authorities (LAs) across England had adopted takeaway management zones (or âexclusion zonesâ) around schools as a means to curb proliferation of new takeaways. In this nationwide, natural experimental study, we evaluated the impact of management zones on takeaway retail, including unintended displacement of takeaways to areas immediately beyond management zones, and impacts on chain fast-food outlets. We used uncontrolled interrupted time series analyses to estimate changes from up to six years pre- and post-adoption of takeaway management zones around schools. We evaluated three outcomes: mean number of new takeaways within management zones (and by three identified sub-types: full management, town centre exempt and time management zones); mean number on the periphery of management zones (i.e. within an additional 100 m of the edge of zones); and presence of new chain fast-food outlets within management zones. For 26 LAs, we observed an overall decrease in the number of new takeaways opening within management zones. Six years post-intervention, we observed 0.83 (95% CI -0.30, â1.03) fewer new outlets opening per LA than would have been expected in absence of the intervention, equivalent to an 81.0% (95% CI -29.1, â100) reduction in the number of new outlets. Cumulatively, 12 (54%) fewer new takeaways opened than would have been expected over the six-year post-intervention period. When stratified by policy type, effects were most prominent for full management zones and town centre exempt zones. Estimates of intervention effects on numbers of new takeaways on the periphery of management zones, and on the presence of new chain fast-food outlets within management zones, did not meet statistical significance. Our findings suggest that management zone policies were able to demonstrably curb the proliferation of new takeaways. Modelling studies are required to measure the possible population health impacts associated with this change.Peer reviewe
Galaxy and Cluster Biasing from Local Group Dynamics
Comparing the gravitational acceleration induced on the Local Group of
galaxies by different tracers of the underline density field we estimate,
within the linear gravitational instability theory and the linear biasing
ansatz, their relative bias factors. Using optical SSRS2 galaxies, IRAS (PSCz)
galaxies and Abell/ACO clusters, we find b_{O,I} ~ 1.21 +- 0.06 and b_{C,I} ~
4.3 +- 0.8, in agreement with other recent studies. Finally, there is an
excellent one-to-one correspondence of the PSCz and Abell/ACO cluster dipole
profiles, once the latter is rescaled by b_{C,I}, out to at least ~150 h^{-1}
Mpc.Comment: 7 pages, 5 figures, accepted for publication in MNRA
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