949 research outputs found
Top Physics from Run 1 and Run 2 Prospects at CDF
We present a summary of top quark physics results from Run 1 at CDF using the
Run 1 data sample of 106 pb. In addition to the precursory measurements
of the top quark mass and \ttbar cross section, we have performed a number of
other analyses which test the consistency of the \ttbar data sample with the
standard model (SM). Deviations from SM expectations could provide hints for
new physics. We find that the data are consistent with the SM. While the Run 1
data are statistically limited, we have shown that the systematic uncertainties
are under control and thus have layed the groundwork for higher precision tests
of the SM in Run 2. This report describes the Run 1 top quark analyses and
expectations and prospects for top quark measurements in Run 2.Comment: 3 page
Upsilon Decays at CLEO
Using data collected using the CLEO III detector, we present recent results
on decays of the resonances. We report on three
analyses. They are: (1) improved measurements of the muonic branching fraction
of the , (2) precision measurements of
and photonic transitions, and (3) new
measurements of decays to charmonium final states.}]Comment: 4 pages, 5 figures. Submitted to 32nd International Conference on
High-Energy Physics (ICHEP 04), Beijing, China, 16-22 Aug 200
Measurement of the Top Quark Mass
In this paper, we report on the most recent measurements of the top quark
mass, performed by the CDF and D0 collaborations at the Fermilab Tevatron. The
CDF collaboration has performed measurements of the top quark mass in three
decay channels from which the top quark mass is measured to be 175.6 +- 6.8
GeV/c^2. The D0 collaboration combines measurements from two decay channels to
obtain a top quark mass of 172.1 +- 7.1 GeV/c^2. Combining the measurements
from the two experiments, assuming a 2 GeV/c^2 correlated systematic
uncertainty, the measurement of the top quark mass at the Tevatron is 173.9 +-
5.2 GeV/c^2. This report presents the measurements of the top quark mass from
each of the decay channels which contribute to this measurement.Comment: To be published in the 33rd proceedings of the Recontres de Moriond,
Les Arcs, France, March 21-28, 1998. 6 pages, 3 figure
Testbeam studies of pre-prototype silicon strip sensors for the LHCb UT upgrade project
The LHCb experiment is preparing for a major upgrade in 2018-2019. One of the
key components in the upgrade is a new silicon tracker situated upstream of the
analysis magnet of the experiment. The Upstream Tracker (UT) will consist of
four planes of silicon strip detectors, with each plane covering an area of
about 2 m. An important consideration of these detectors is their
performance after they have been exposed to a large radiation dose. In this
article we present test beam results of pre-prototype n-in-p and p-in-n sensors
that have been irradiated with fluences up to
cm.Comment: 25 pages, 20 figure
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires
The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of , and is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 0.02 \mbox{fb}^{-1}. The bosons are reconstructed in the decays , where denotes muon or electron, while the and quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions
LHCb upgrade software and computing : technical design report
This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis
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