1,429 research outputs found
Standard model explanation of a CDF dijet excess in Wjj
We demonstrate the recent observation of a peak in the dijet invariant mass
of the Wjj signal observed by the CDF Collaboration can be explained as the
same upward fluctuation observed by CDF in single-top-quark production. In
general, both t-channel and s-channel single-top-quark production produce
kinematically induced peaks in the dijet spectrum. Since CDF used a Monte Carlo
simulation to subtract the single-top backgrounds instead of data, a peak in
the dijet spectrum is expected. The D0 Collaboration has a small upward
fluctuation in their published t-channel data; and hence we predict they would
see at most a small peak in the dijet invariant mass spectrum of Wjj if they
follow the same procedure as CDF.Comment: 3 pg., 2 figs, revtex, minor clarifications, to appear in Phys. Rev.
Angular correlations in single-top-quark and Wjj production at next-to-leading order
I demonstrate that the correlated angular distributions of final-state
particles in both single-top-quark production and the dominant Wjj backgrounds
can be reliably predicted. Using these fully-correlated angular distributions,
I propose a set of cuts that can improve the single-top-quark discovery
significance by 25%, and the signal to background ratio by a factor of 3 with
very little theoretical uncertainty. Up to a subtlety in t-channel
single-top-quark production, leading-order matrix elements are shown to be
sufficient to reproduce the next-to-leading order correlated distributions.Comment: 22 pages, 23 figs, RevTex4, fixed typos, to appear in Phys. Rev.
A White Ash (Fraxinus americana) Status Assessment and Emerald Ash Borer (Agrilus planipennis) Management Plan for the Gordon Natural Area
Facebook polls as proto-democratic instruments in the Egyptian revolution: The ‘We Are All Khaled Said’ Facebook page
A Page and Its Politics: Situating Kullinā Khālid Saʿīd in Egypt’s Ideological Landscape at the Time of Revolution
In discussions concerning the importance of social media in the 25January revolution, a central role is given to the "Kullinā Khālid Saʿīd" [We’re all Khaled Said] Facebook page. Using an advanced data collection and extraction application called Netvizz, a research team consisting of Arabists and Media studies specialists has collected and analysed all of the posts and comments exchanged through the page. This data set allows for a systematic analysis of the page. This article offers an outline of the ideological nature of "Kullinā Khālid Saʿīd", with particular emphasis on the "revolutionary" period between 1 January - 11 February 2011. It argues that the page shows no evidence of political bias in the sense of explicit favoring of a political group. Rather, the page constituted a community of users who abstained from using politically factional language. Reflecting the mood and concerns of the revolution’s grassroots masses, it clearly illustrates the disinclination to engage with formal politics
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