3,708 research outputs found
Determination of the strong coupling constant at LEP
Multi-hadronic events produced in e+e- collisions provide an excellent
laboratory to study QCD, the theory of strong interactions, and in particular
to determine the strong coupling parameter alpha_s and demonstrate its
predicted behavior as a function of the energy scale. Determinations of alpha_s
at LEP will be reviewed with emphasis on event shape variables and jet rates in
3-jet and 4-jet events.Comment: Proceedings of DIS06, XIV International Workshop on Deep Inelastic
Scattering, Tsukuba, Japan, 20-24 April 2006, 4 pages, 2 figure
Forward pi^0-meson production at HERA
The production of high transverse momentum piz^0-mesons has been measured in
deep-inelastic e-p scattering events at low Bjorken- taken with the
H1 detector at HERA. The production of high p_T particles is strongly
correlated to the emission of hard partons in QCD and is therefore sensitive to
the dynamics of the strong interaction. For the first time the measurement of
single particles has been extended to the region of small angles w.r.t. the
proton remnant (forward region) and down to very low values of x ~ 5x10^-5.
This region is expected to be particularly sensitive to QCD evolution effects
in final states. Differential cross sections of inclusive pi^0-meson production
have been measured as a function of Bjorken-x and the four-momentum transfer
Q^2, and also as a function of the transverse momentum and the polar angle of
the pi^0-mesons. A recent BFKL calculation and QCD models based on the DGLAP
splitting functions are compared to the data. The best description of the data
is achieved by the BFKL calculation.Comment: 3 pages, 2 figures, talk given on behalf of the H1 collaboration at
DIS99, Zeuthe
Forward -Meson and Charged Particle Production in Deep Inelastic Scattering at low Bjorken-x
High transverse momentum pi^0 -mesons and charged particles are measured in deep inelastic e-p scattering events at low Bjorken-x taken with the H1 detector at HERA. The production of high-pt particles is strongly correlated to the emission of hard partons in QCD and is therefore sensitive to the dynamics of the strong interaction. For the first time the measurement of single particles has been extended to the region of small angles w.r.t. the proton remnant (forward region). This region is expected to be particularly sensitive to QCD evolution effects in final states. Results are presented as a function of Bjorken-x and x_i, the fraction of the incident proton's energy carried by the particle, and are compared to different QCD models
Sense-Making and the Community College Student
A qualitative pilot study is underway at Queensborough Community College - The City University of New York to explore the information behaviors of community college students in the context of an assigned research task. Two research questions are addressed: RQ1: How do community college students make sense of research assignments?; RQ2: What role does the academic library play in community college students’ sense-making processes?
This project is framed using Dervin’s Sense-Making Theory of Information Behavior (Dervin, 1998). Community college students are interviewed and asked to reconstruct their experience in the completion of a research assignment. Per Dervin’s model, the assignment is conceived as a time-space journey, and the journey is comprised of a series of student-conceptualized situations and gaps, bridges and outcomes. Data is collected using Sense-Making’s micro moment time-line interview technique (Dervin, 1983) and analyzed using a grounded theory approach (Charmaz, 2006). This study hopes to expand human information behavior and user study literature with a focus on the community college student; it will also close a methodological gap in the community college scholarship with a Sense-Making approach to data collection. Pilot findings may offer insights into the refinement of academic library sources and services, which could contribute to community college student achievement, and may be used to launch a larger mixed-methods inquiry regarding this user population. The poster will discuss research study methodology and data collection, as well as present preliminary findings and interview themes
A Low Noise Receiver for Submillimeter Astronomy
A broadband, low noise heterodyne receiver, suitable for astronomical use, has been built using a Pb alloy superconducting tunnel junction (SIS). The RF coupling is quasioptical via a bowtie antenna on a quartz lens and is accomplished without any tuning elements. In its preliminary version the double sideband receiver noise temperature rises from 205 K at 116 GHz to 815 K at 466 GHz. This is the most sensitive broadband receiver yet reported for sub-mm wavelengths. Its multi-octave sensitivity and low local oscillator power requirements make this receiver ideal for remote ground observatories or space-borne telescopes such as NASA's Large Deployable Reflector. A version of this receiver is now being built for NASA's Kuiper Airborne Observatory
A configuration system for the ATLAS trigger
The ATLAS detector at CERN's Large Hadron Collider will be exposed to
proton-proton collisions from beams crossing at 40 MHz that have to be reduced
to the few 100 Hz allowed by the storage systems. A three-level trigger system
has been designed to achieve this goal. We describe the configuration system
under construction for the ATLAS trigger chain. It provides the trigger system
with all the parameters required for decision taking and to record its history.
The same system configures the event reconstruction, Monte Carlo simulation and
data analysis, and provides tools for accessing and manipulating the
configuration data in all contexts.Comment: 4 pages, 2 figures, contribution to the Conference on Computing in
High Energy and Nuclear Physics (CHEP06), 13.-17. Feb 2006, Mumbai, Indi
Next Level Learning: Using Pedagogically-Designed Research Guides in Information Literacy Instruction
A pilot study is currently underway at Queensborough Community College which explores the impact of a pedagogically-designed research guide (PDRG) on information literacy student learning outcomes. In contrast to pathfinder guides, the PDRG seeks to engage and support students through all steps of the research assignment. Each guide tab corresponds to a stage in Kuhlthau’s Model of the Information Search Process and includes both a micro-lecture and a quiz. The poster will discuss the creation and Spring 2018 launch of the PDRG. Poster visual aids will incorporate graphic presentation of the micro-lectures and quizzes, as well as preliminary quiz results. Micro-lecture videos will be available for viewing and their production discussed
A Low Noise Receiver for Submillimeter Astronomy
A broadband, low noise heterodyne receiver, suitable for astronomical use, has been built using a Pb alloy superconducting tunnel junction (SIS). The RF coupling is quasioptical via a bowtie antenna on a quartz lens and is accomplished without any tuning elements. In its preliminary version the double sideband receiver noise temperature rises from 205 K at 116 GHz to 815 K at 466 GHz. This is the most sensitive broadband receiver yet reported for sub-mm wavelengths. Its multi-octave sensitivity and low local oscillator power requirements make this receiver ideal for remote ground observatories or space-borne telescopes such as NASA's Large Deployable Reflector. A version of this receiver is now being built for NASA's Kuiper Airborne Observatory
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