948 research outputs found
High Rate Neutrino Detectors for Neutrino Factories
Three types of high rate neutrino detectors for neutrino interaction physics
at neutrino factories are discussed. High performance general-purpose detectors
might collect event samples on the order of a billion events or more. This
could greatly improve on existing analyses of neutrino interactions and also
lead to new and important analysis topics including, for example, precise
determinations of the CKM matrix elements |Vub| and |Vcb|. The potential of
such general purpose detectors is illustrated with reference to a detector,
presented previously in reference hep-ex/9907033, that is structured around a
novel and compact vertexing and tracking neutrino target comprising a stack of
CCD pixel devices. Design ideas and prospects are also discussed for two types
of specialized detectors: (i) polarized targets filled with polarized solid
protium-deuterium (HD), for unique and powerful studies of the nucleon's spin
structure, and (ii) Fully active liquid tracking targets with masses of several
tonnes for precise determinations of the weak mixing angle, from the total
cross-section for neutrino-electron scattering. All three detector types pose
severe technical challenges but their utilization could add significantly to
the physics motivation for neutrino factories.Comment: 12 pages, 1 figure. Submitted to Proc. ICFA/ECFA Workshop "Neutrino
Factories based on Muon Storage Rings" (nuFACT'99), Lyon, France, 5--9 July,
199
Employee Use of the Internet and Acceptable Use Policies in the Academic Workplace: Controlling Abuse while Creating Culture.
The use of the Internet has grown substantially, especially since the late 1990s. Businesses are relying increasingly on the Internet and intranet as tools to promote productivity. Use of the Internet has several implications for institutions of higher education. Some of the issues institutions are faced with include legal liability for defamatory postings and sexually explicit materials, monitoring versus privacy, motivations to abuse Internet privileges, and use of the Internet to create a corporate culture. Institutions of higher education need to consider how the Internet is being used and how it should be used when acceptable use policies are being formulated.
The purpose of this quantitative study was to gain an understanding of perceptions about acceptable use of the Internet by employees at work, attitudes about personal use of the Internet during working hours, and the knowledge and effectiveness of an acceptable use policy within the context of institutions of higher education. The data gathered could be used as a foundation for an effective, progressive acceptable use policy for higher education.
The data for the research were gathered from December, 2005 through January of 2006. Six 4-year institutions were surveyed. The study revealed older employees responded that the use of the Internet at work as not acceptable, while younger employees, faculty members and respondents with more Internet experience or more hours of overtime indicated that personal use was acceptable. The study identified significant differences in self-reported use of the Internet, both at home and at work. Additionally, a general lack of knowledge existed regarding an institutional Internet acceptable use policy. The results of the study were applicable to the formulation of policy for institutions of higher education
Dynamics of manganese, cadmium, and lead in experimental power plant ponds
This study was designed to determine the effect of heated power plant cooling water on the compartmentalization of manganese, lead and cadmium in experimental ponds. Caged channel catfish and green sunfish were kept in an experimental pond and a control pond. Periodically, whole fishes, gill, heart, kidney, liver and musculature were analyzed for the three metals. Concentrations of the three metals in fishes were not affected by the temperature differential maintained during the study. There was no correlation in concentrations of cadmium and lead with age (weight and length) of fishes but manganese concentrations declined slightly with age. The water component of the system contained the lowest concentration of the metals with sediments acting as a characteristic sink. Concentrations of the three metals in water and sediments of the ponds were unaffected by heat inasmuch as concentration differences between ponds were not significant at the .05 level. Aquatic organisms such as snails, fingernail clams, leeches, tubificid annelids and dragonfly nymphs exhibited concentrations of cadmium higher than sediments while snails and duckweed more closely reflected concentrations of manganese in sediments. Tubificid worms and leeches more closely reflected lead concentrations in sediments while fingernail clams and snails exhibited higher concentrations.U.S. Department of the InteriorU.S. Geological SurveyOpe
Epistemic and social scripts in computer-supported collaborative learning
Collaborative learning in computer-supported learning environments typically means that learners work on tasks together, discussing their individual perspectives via text-based media or videoconferencing, and consequently acquire knowledge. Collaborative learning, however, is often sub-optimal with respect to how learners work on the concepts that are supposed to be learned and how learners interact with each other. One possibility to improve collaborative learning environments is to conceptualize epistemic scripts, which specify how learners work on a given task, and social scripts, which structure how learners interact with each other. In this contribution, two studies will be reported that investigated the effects of epistemic and social scripts in a text-based computer-supported learning environment and in a videoconferencing learning environment in order to foster the individual acquisition of knowledge. In each study the factors ‘epistemic script’ and ‘social script’ have been independently varied in a 2×2-factorial design. 182 university students of Educational Science participated in these two studies. Results of both studies show that social scripts can be substantially beneficial with respect to the individual acquisition of knowledge, whereas epistemic scripts apparently do not to lead to the expected effects
Nuclear Structure Functions in the Large x Large Q^2 Kinematic Region in Neutrino Deep Inelastic Scattering
Data from the CCFR E770 Neutrino Deep Inelastic Scattering (DIS) experiment
at Fermilab contain events with large Bjorken x (x>0.7) and high momentum
transfer (Q^2>50 (GeV/c)^2). A comparison of the data with a model based on no
nuclear effects at large x, shows a significant excess of events in the data.
Addition of Fermi gas motion of the nucleons in the nucleus to the model does
not explain the excess. Adding a higher momentum tail due to the formation of
``quasi-deuterons'' makes some improvement. An exponentially falling F_2
\propto e^-s(x-x_0) at large x, predicted by ``multi-quark clusters'' and
``few-nucleon correlations'', can describe the data. A value of s=8.3 \pm
0.7(stat.)\pm 0.7(sys.) yields the best agreement with the data.Comment: 4 pages, 4 figures, 1 table. Sibmitted to PR
The Potential for Neutrino Physics at Muon Colliders and Dedicated High Current Muon Storage Rings
Conceptual design studies are underway for muon colliders and other
high-current muon storage rings that have the potential to become the first
true ``neutrino factories''. Muon decays in long straight sections of the
storage rings would produce precisely characterized beams of electron and muon
type neutrinos of unprecedented intensity. This article reviews the prospects
for these facilities to greatly extend our capabilities for neutrino
experiments, largely emphasizing the physics of neutrino interactions.Comment: 107 pages, 16 figures, to be published in Physics Report
A Precise Measurement of the Weak Mixing Angle in Neutrino-Nucleon Scattering
We report a precise measurement of the weak mixing angle from the ratio of
neutral current to charged current inclusive cross-sections in deep-inelastic
neutrino-nucleon scattering. The data were gathered at the CCFR neutrino
detector in the Fermilab quadrupole-triplet neutrino beam, with neutrino
energies up to 600 GeV. Using the on-shell definition, , we obtain .Comment: 10 pages, Nevis Preprint #1498 (Submitted to Phys. Rev. Lett.
Towards a rhizomatic understanding of the desistance journey
Although the ‘desistance as a (zigzag) journey’ metaphor has proved useful in terms of translating theory into practice, this article makes the case that it is insufficient for conveying the truly complex, social, unpredictable and ‘messy’ process of desistance from crime. The article uses what we know about the process of desistance to discuss the utility of Deleuze and Guattari’s (2013) rhizomatic theory in recasting the desistance journey metaphor. In doing so it is suggested that the desistance journey should be understood in terms of its endless and multiplicitous nature, a symbol of metamorphosis, and it argues that our focus should be on understanding the ‘desister as nomad’. This, the article concludes, holds important ramifications for the way in which we understand and implement desistance-focused practice in the criminal justice system
Determination of the Strange Quark Content of the Nucleon from a Next-to-Leading-Order QCD Analysis of Neutrino Charm Production
We present the first next-to-leading-order QCD analysis of neutrino charm
production, using a sample of 6090 - and -induced
opposite-sign dimuon events observed in the CCFR detector at the Fermilab
Tevatron. We find that the nucleon strange quark content is suppressed with
respect to the non-strange sea quarks by a factor \kappa = 0.477 \:
^{+\:0.063}_{-\:0.053}, where the error includes statistical, systematic and
QCD scale uncertainties. In contrast to previous leading order analyses, we
find that the strange sea -dependence is similar to that of the non-strange
sea, and that the measured charm quark mass, , is larger and consistent with that determined in other processes.
Further analysis finds that the difference in -distributions between
and is small. A measurement of the Cabibbo-Kobayashi-Maskawa
matrix element is also presented.
uufile containing compressed postscript files of five Figures is appended at
the end of the LaTeX source.Comment: Nevis R#150
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