432 research outputs found
Non-perturbative effects and the resummed Higgs transverse momentum distribution at the LHC
We investigate the form of the non-perturbative parameterization in both the
impact parameter (b) space and transverse momentum (p_T) space resummation
formalisms for the transverse momentum distribution of single massive bosons
produced at hadron colliders. We propose to analyse data on Upsilon
hadroproduction as a means of studying the non-perturbative contribution in
processes with two gluons in the initial state. We also discuss the theoretical
errors on the resummed Higgs transverse momentum distribution at the LHC
arising from the non-perturbative contribution.Comment: 22 pages, 10 figure
Same-sign W pair production as a probe of double parton scattering at the LHC
We study the production of same-sign W boson pairs at the LHC in double
parton interactions. Compared with simple factorised double parton
distributions (dPDFs), we show that the recently developed dPDFs, GS09, lead to
non-trivial kinematic correlations between the W bosons. A numerical study of
the prospects for observing this process using same-sign dilepton signatures,
including same-sign WWjj, di-boson and heavy flavour backgrounds, at 14 TeV
centre-of-mass energy is then performed. It is shown that a small excess of
same-sign dilepton events from double parton scattering over a background
dominated by single scattering WZ(gamma*) production could be observed at the
LHC.Comment: 14 pages, 8 figures. Added references, slight changes in the text
Service Learning as Inquiry in an Undergraduate Science Course
To engage students in applying scientific process skills to real-world issues, we implemented a service-learning project model in our undergraduate introductory biology course for science majors. This model illustrates how we integrate inquiry inside and outside of the classroom through four steps: service, learning, classroom, and community. Out-of-class activities engaged students in serving the community (Service step) while deepening their learning experience beyond what they would learn in a classroom (Learning step). To connect the service-learning project with scientific process skills, students were asked to identify problems that our community partners were trying to solve, identify proposed solutions, and design ways to evaluate those solutions (Classroom step). Additionally, students connected their service-learning topic with core concepts in Biology. After their service, students used metrics to analyze their impact. Students then synthesized the connection between their service, learning, and classroom projects by presenting their findings to the scientific and lay communities through a poster session (Community step). Here we provide details of the model, recommendations, and examples for others to execute an inquiry-based service-learning project
Soft gluon resummation for squark and gluino pair-production at hadron colliders
We report on the study of soft gluon effects in the production of squarks and
gluinos at hadron colliders. Close to production threshold, the emission of
soft gluon results in the appearence of large logarithmic corrections in the
theoretical expressions. In order to resum these corrections at
next-to-leading-logarithmic accuracy appropriate one-loop anomalous dimensions
have to be calculated. We present the calculation of the anomalous dimensions
for all production channels of squarks and gluinos and provide numerical
predictions for the Tevatron and the LHC.Comment: 6 pages, talk given at RADCOR 2009 - 9th International Symposium on
Radiative Corrections (Applications of Quantum Field Theory to Phenomenology)
October 25-30 2009, Ascona, Switzerlan
Education for persons with special needs: Polish and Russian experience
© Author(s).The beginning of the 21st century is marked by systemic, economic and social transformations in Poland and Russia, that significantly affected the education system, including the education for persons with special needs. This paper is an attempt to present synthetically the changes relating to persons with disabilities. The current state of the education for children and youth with special needs will be considered due to the new education system, legal regulations, the school population, type of disability of pupils and the kinds of schools they attend. Compulsory education, which includes the level of primary and lower secondary schools, will be subject to a separate analysis. The article presents significant systemic changes in Polish and Russian education and the state development strategy in the sphere of social policy towards persons with disabilities. The new documents are analyzed that have led to important changes in policy direction with serious consequences in terms of the structure and curriculum of inclusive education in both countries. The paper introduces a review of the changes in policy direction with serious consequences in terms of the structure and curriculum of education for persons with special needs. A key objective of the paper will be to examine the new approaches to education of disabled persons in Russia and Poland and the subsequent changes in it
Supersymmetric top and bottom squark production at hadron colliders
The scalar partners of top and bottom quarks are expected to be the lightest
squarks in supersymmetric theories, with potentially large cross sections at
hadron colliders. We present predictions for the production of top and bottom
squarks at the Tevatron and the LHC, including next-to-leading order
corrections in supersymmetric QCD and the resummation of soft gluon emission at
next-to-leading-logarithmic accuracy. We discuss the impact of the higher-order
corrections on total cross sections and transverse-momentum distributions, and
provide an estimate of the theoretical uncertainty due to scale variation and
the parton distribution functions.Comment: 29 pages, 6 figure
Snowmass 2001: Jet Energy Flow Project
Conventional cone jet algorithms arose from heuristic considerations of LO
hard scattering coupled to independent showering. These algorithms implicitly
assume that the final states of individual events can be mapped onto a unique
set of jets that are in turn associated with a unique set of underlying hard
scattering partons. Thus each final state hadron is assigned to a unique
underlying parton. The Jet Energy Flow (JEF) analysis described here does not
make such assumptions. The final states of individual events are instead
described in terms of flow distributions of hadronic energy. Quantities of
physical interest are constructed from the energy flow distribution summed over
all events. The resulting analysis is less sensitive to higher order
perturbative corrections and the impact of showering and hadronization than the
standard cone algorithms.Comment: REVTeX4, 13 pages, 6 figures; Contribution to the P5 Working Group on
QCD and Strong Interactions at Snowmass 200
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