80,838 research outputs found
Sigma pole position and errors of a once and twice subtracted dispersive analysis of pi-pi scattering data
We show how the new precise data on kaon decays together with forward
dispersion relations, sum rules and once- and twice-subtracted
Roy's equations allow for a precise determination of the sigma meson pole
position. We present a comparison and a study of the different sources of
uncertainties when using either once- or twice-subtracted Roy's equations to
analyze the data. Finally we present a preliminary determination of the sigma
pole from the constrained dispersive data analysis.Comment: 4 pages, 6 figures. Contribution to the proceedings of the QCD08 14th
International QCD Conference. 7-12th July 2008 Montpellier (France); one
reference removed, changed errors in Eqs (4), (5) and (7
Effects of substrate deformation and sip thickness on tile/sip interface stresses for shuttle thermal protection
A nonlinear analysis was used to study the effects of substrate deformation characteristics and strain isolator pad (SIP) thickness on TILE/SIP interface stresses for the space shuttle thermal protection system. The configuration analyzed consisted of a 5.08 cm thick, 15.24 cm square tile with a 12.7 cm square SIP footprint bordered by a 1.27 cm wide filler bar and was subjected to forces and moments representative of a 20.7 kPa aerodynamic shock passing over the tile. The SIP stress deflection curves were obtained after a 69 kPa proof load and 100 cycles conditioning at 55 kPa. The TILE/SIP interface stresses increase over flat substrate values for zero to peak substrate deformation amplitudes up to 0.191 cm by up to a factor of nearly five depending on deformation amplitude, half wave length, and location. Stresses for a 0.23 cm thick SIP found to be up to 60 percent greater than for a 0.41 cm thick SIP for identical loads and substrate deformation characteristics. A simplified method was developed for approximating the substrate location which produces maximum TILE/SIP interface stresses
The use of Planetary Nebulae precursors in the study of Diffuse Interstellar Bands
We present the first results of a systematic search for Diffuse Interstellar
Bands in a carefully selected sample of post-AGB stars observed with high
resolution optical spectroscopy. These stars are shown to be ideal targets to
study this old, intriguing astrophysical problem. Our results suggest that the
carrier(s) of these bands may not be present in the circumstellar environments
of these evolved stars. The implications of the results obtained on the
identification of the still unknown carrier(s) are discussed.Comment: 4 pages, 2 figures, proceedings of the conference 'Planetary Nebulae
as Astrophysical Tools', held in Gdansk, Poland (June 28 - July 2, 2005
New Experiments in Minority Voter Mobilization: Second in a Series of Reports on the California Votes Initiative
During the first phase of the California Votes Initiative, spanning elections from June 2006 to March 2007, participating community-based organizations personally contacted over 82,000 low-propensity voters, through strategies such as door-to-door outreach and phone calls, plus reached an additional 100,000 voters through less direct methods, such as voter forums and messages to congregations. This outreach inspired many to participate in the electoral process for the first time. The initiative evaluation team worked with the community organizations to imbed field experiments into their outreach efforts, comparing turnout among those targeted for contact and those assigned to control groups. This resulted in strong empirical support for a series of best practices that were detailed in a September 2007 report.1 A second phase of the initiative has continued this path-breaking research with further field experiments in the February and June 2008 elections, with more planned for November 2008. This report briefly reviews the results from the first phase of the initiative, adds findings from February 2008 and June 2008 as available,2 and outlines the follow-up studies planned for November 2008. Many findings from the first phase were confirmed, and the two rounds of experiments conducted so far this year provide valuable refinements to the list of best practices established in that earlier report. 1 Michelson, Melissa R., Lisa Garcia Bedolla and Donald P. Green. 2007. "New Experiments in Minority Voter Mobilization: A Report on the California Votes Initiative" (San Francisco, CA: The James Irvine Foundation). Available at www.irvine.org. 2 In many counties, particularly large ones such as Los Angeles, voting information is not released until several months after an election
New Experiments in Minority Voter Mobilization: Third and Final Report on the California Votes Initiative
This report offers new insights about voter mobilization strategies used in our California Votes Initiative. Launched in 2006, the initiative supported nine nonprofit organizations as they reached out to infrequent voters in low-income and ethnic communities in the San Joaquin Valley and parts of Southern California. This publication, the third and final report on the initiative, summarizes findings from the entirety of the project's experiments. It examines the long-term effects of voter mobilization and the effects of specific approaches, such as canvassing and phone calls, on voter attitudes toward politics and political engagement. Qualitative analyses explore the components of a successful get-out-the-vote campaign and identify five practices organizations of many types may use to increase turnout
New Experiments in Minority Voter Mobilization: A Report on the California Votes Initiative
Evaluates the effectiveness of efforts in California to mobilize voters in communities with significant low-income and minority populations
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