906 research outputs found
Total Photonic and Hadronic Cross-sections
We discuss total cross-sections within the context of the QCD calculable
mini-jet model, highlighting its successes and failures. In particular we show
its description of and compare it with OPAL and L3
data. We extrapolate this result to total cross-sections and propose
a phenomenological ans\"atz for virtual photon cross-sections. We point out
that the good agreement with data obtained with the Eikonal Minijet Model
should not hide the many uncertainties buried in the impact parameter
distribution. A model obtained from Soft Gluon Summation is briefly discussed
and its application to hadronic cross-sections is shown.Comment: 10 pages, 5 figures, LaTeX, uses aipproc.sty. To appear in the
proceedings of Photon 2000, Ambelside, U.K., Aug 2000. The title, the number
of pages and the number of figures in the announcement were corrected to
correspond to the submitted pape
Total Cross Sections
A unified approach to total cross-sections, based on the QCD contribution to
the rise with energy, is presented for the processes , , . For proton processes, a discussion of
the role played by soft gluon summation in taming the fast rise due to
mini-jets is presented. For photon-photon processes, a comparison with other
models indicates the need for precision measurements in both the low and high
energy region, likely only with measurements at future Linear Colliders.Comment: 15 pages, 9 figures, LaTeX, uses hsproc.sty and art10.sty. Talk given
by G. Pancheri at 'International Hadron Structure-2000', October 1-6,
Staralesn
Lab-frame observables for probing the top-Higgs interaction
We investigate methods to explore the CP nature of the coupling
at the LHC, focusing on associated production of the Higgs with a
pair. We first discuss the constraints implied by low-energy observables and by
the Higgs-rate information from available LHC data, emphasizing that they
cannot provide conclusive evidence on the nature of this coupling. We then
investigate kinematic observables that could probe the coupling
directly, in particular quantities that can be constructed out of just
lab-frame kinematics. We define one such observable by exploiting the fact that
spin correlations do also carry information about the CP-nature of
the coupling. Finally, we introduce a CP-odd quantity and a
related asymmetry, able to probe CP violation in the coupling and
likewise constructed out of lab-frame momenta only.Comment: 32 pages, updated with latest data from ATLAS and references adde
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Exploring Afghani Culture Through Literature
This lesson explores how literature written by an Afghani author offers insight into Afghani culture leading up to 9/11. Students should be familiar with the effects of the Middle Eastern colonial experience—and the subsequent challenges of the postcolonial era. They should consider religious, generational, and cultural conflicts, effects of modernization, political struggle, and other themes common to many literary works. In order to enrich their understanding, students should investigate the historical background for the selected works. The set of questions below applies to both books, although each books highlights unique facets of Afghani life (i.e. A Thousand Splendid Suns specifically explores the role of women; The Kite Runner studies socioeconomic issues). The books, then, can either serve as an in-depth author study and be read in sequence, or serve as stand-alone units. Most of the questions are taken from the Core Curriculum Maps so to ensure relevance in your classroom
Azimuthal Angle Probe of Anomalous HWW Couplings at the LHeC
A high energy ep collider, such as the proposed LHeC, possesses the unique
facility of permitting direct measurement of the HWW coupling without
contamination from the HZZ coupling. At such a machine, the fusion of two W
bosons through the HWW vertex would give rise to typical charged current (CC)
events accompanied by a Higgs boson. We demonstrate that azimuthal angle
correlations between the observable CC final states could then be a sensitive
probe of the nature of the HWW vertex and hence of the CP properties of the
Higgs boson.Comment: Revised version to appear in Physical Review Letters, some typos and
mis-labellings corrected, references reorganised and update
Survey of vector-like fermion extensions of the Standard Model and their phenomenological implications
With the renewed interest in vector-like fermion extensions of the Standard
Model, we present here a study of multiple vector-like theories and their
phenomenological implications. Our focus is mostly on minimal flavor conserving
theories that couple the vector-like fermions to the SM gauge fields and mix
only weakly with SM fermions so as to avoid flavor problems. We present
calculations for precision electroweak and vector-like state decays, which are
needed to investigate compatibility with currently known data. We investigate
the impact of vector-like fermions on Higgs boson production and decay,
including loop contributions, in a wide variety of vector-like extensions and
their parameter spaces.Comment: 43 pages, 17 figures; v2: text modified to improve readability,
references added, journal versio
Jet substructure and probes of CP violation in Vh production
We analyse the hVV (V = W, Z) vertex in a model independent way using Vh
production. To that end, we consider possible corrections to the Standard Model
Higgs Lagrangian, in the form of higher dimensional operators which parametrise
the effects of new physics. In our analysis, we pay special attention to linear
observables that can be used to probe CP violation in the same. By considering
the associated production of a Higgs boson with a vector boson (W or Z), we use
jet substructure methods to define angular observables which are sensitive to
new physics effects, including an asymmetry which is linearly sensitive to the
presence of CP odd effects. We demonstrate how to use these observables to
place bounds on the presence of higher dimensional operators, and quantify
these statements using a log likelihood analysis. Our approach allows one to
probe separately the hZZ and hWW vertices, involving arbitrary combinations of
BSM operators, at the Large Hadron Collider.Comment: 37 pages, 17 figures; v3 matches published versio
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Does Revolution Work? Evidence from Nepal’s People’s War
In 2015, after a decade-long conflict and nine years of negotiation, Nepal promulgated a constitution that replaced its 240-year-old monarchy by a federal republic. The subsequent 2017 local elections ushered more than 30,000 first-time politicians into office. Using a census of 3.68 million Nepalis (2.56 million of whom are of voting age) covering eleven districts, party nomination lists and party candidate selection committee surveys, electoral data and information on conflict incidence, we document that castes that were historically excluded from political representation achieved representation without a significant representation-ability trade-off: improved social representation among politicians is accompanied by positive selection on education and income. Triangulating across multiple data sources, we show that the entry of the revolutionary Maoist group as a post-conflict mainstream party played an important role. Finally, political representation of non-elite castes improved their policy inclusion as measured by individual access to earthquake reconstruction transfers. These gains, however, vary with the extent of social connections to the elected mayor and point to a continuing need to balance power by supporting institutions that provide all citizens political voice
Use of information technology in healthcare sector for improving outcomes
With revolutionary success of internet and mobile usage in India, use of information technology for healthcare promotion by pharmaceutical industry and other healthcare sectors is increasing. Information technology provides an unlimited opportunity for promoting correct healthcare practices for prevention of certain diseases, providing information for maintaining health and other suitable information to the expected target audience. Information technology provides numerous advantages including extended reach, quick dissemination of facts, providing unlimited amount of information and also eliminates the need of large number of manual resources. There is enormous potential for improving the awareness about healthcare through digital media and information technology. However, with its increasing usage, there are some challenges, responsibilities and precautions which need to be considered while using information technology as a resource for healthcare promotion. This article discusses the use of information technology in healthcare promotion along with the challenges in its usage
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