94 research outputs found
Modeless Pointing with Low-Precision Wrist Movements
Part 1: Long and Short Papers (Continued)International audienceWrist movements are physically constrained and take place within a small range around the hand's rest position. We explore pointing techniques that deal with the physical constraints of the wrist and extend the range of its input without making use of explicit mode-switching mechanisms. Taking into account elastic properties of the human joints, we investigate designs based on rate control. In addition to pure rate control, we examine a hybrid technique that combines position and rate-control and a technique that applies non-uniform position-control mappings. Our experimental results suggest that rate control is particularly effective under low-precision input and long target distances. Hybrid and non-uniform position-control mappings, on the other hand, result in higher precision and become more effective as input precision increases
Autocorrelation analysis for the unbiased determination of power-law exponents in single-quantum-dot blinking
We present an unbiased and robust analysis method for power-law blinking
statistics in the photoluminescence of single nano-emitters, allowing us to
extract both the bright- and dark-state power-law exponents from the emitters'
intensity autocorrelation functions. As opposed to the widely-used threshold
method, our technique therefore does not require discriminating the emission
levels of bright and dark states in the experimental intensity timetraces. We
rely on the simultaneous recording of 450 emission timetraces of single
CdSe/CdS core/shell quantum dots at a frame rate of 250 Hz with single photon
sensitivity. Under these conditions, our approach can determine ON and OFF
power-law exponents with a precision of 3% from a comparison to numerical
simulations, even for shot-noise-dominated emission signals with an average
intensity below 1 photon per frame and per quantum dot. These capabilities pave
the way for the unbiased, threshold-free determination of blinking power-law
exponents at the micro-second timescale
Emulsion sheet doublets as interface trackers for the OPERA experiment
New methods for efficient and unambiguous interconnection between electronic
counters and target units based on nuclear photographic emulsion films have
been developed. The application to the OPERA experiment, that aims at detecting
oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is
reported in this paper. In order to reduce background due to latent tracks
collected before installation in the detector, on-site large-scale treatments
of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd)
packages, each made of a doublet of emulsion films, have been designed,
assembled and coupled to the OPERA target units ("ECC bricks"). A device has
been built to print X-ray spots for accurate interconnection both within the
CSd and between the CSd and the related ECC brick. Sample emulsion films have
been extensively scanned with state-of-the-art automated optical microscopes.
Efficient track-matching and powerful background rejection have been achieved
in tests with electronically tagged penetrating muons. Further improvement of
in-doublet film alignment was obtained by matching the pattern of low-energy
electron tracks. The commissioning of the overall OPERA alignment procedure is
in progress.Comment: 19 pages, 19 figure
The detection of neutrino interactions in the emulsion/lead target of the OPERA experiment
The OPERA neutrino detector in the underground Gran Sasso Laboratory (LNGS)
was designed to perform the first detection of neutrino oscillations in
appearance mode through the study of oscillations. The
apparatus consists of an emulsion/lead target complemented by electronic
detectors and it is placed in the high energy long-baseline CERN to LNGS beam
(CNGS) 730 km away from the neutrino source. Runs with CNGS neutrinos were
successfully carried out in 2007 and 2008 with the detector fully operational
with its related facilities for the emulsion handling and analysis. After a
brief description of the beam and of the experimental setup we report on the
collection, reconstruction and analysis procedures of first samples of neutrino
interaction events
Traditional and new composite endpoints in heart failure clinical trials: facilitating comprehensive efficacy assessments and improving trial efficiency
Composite endpoints are commonly used as the primary measure of efficacy in heart failure clinical trials to assess the overall treatment effect and to increase the efficiency of trials. Clinical trials still must enrol large numbers of patients to accrue a sufficient number of outcome events and have adequate power to draw conclusions about the efficacy and safety of new treatments for heart failure. Additionally, the societal and health system perspectives on heart failure have raised interest in ascertaining the effects of therapy on outcomes such as repeat hospitalization and the patient's burden of disease. Thus, novel methods for using composite endpoints in clinical trials (e.g. clinical status composite endpoints, recurrent event analyses) are being applied in current and planned trials. Endpoints that measure functional status or reflect the patient experience are important but used cautiously because heart failure treatments may improve function yet have adverse effects on mortality. This paper discusses the use of traditional and new composite endpoints, identifies qualities of robust composites, and outlines opportunities for future research
Study of the effects induced by lead on the emulsion films of the OPERA experiment
The OPERA neutrino oscillation experiment is based on the use of the Emulsion
Cloud Chamber (ECC). In the OPERA ECC, nuclear emulsion films acting as very
high precision tracking detectors are interleaved with lead plates providing a
massive target for neutrino interactions. We report on studies related to the
effects occurring from the contact between emulsion and lead. A low
radioactivity lead is required in order to minimize the number of background
tracks in emulsions and to achieve the required performance in the
reconstruction of neutrino events. It was observed that adding other chemical
elements to the lead, in order to improve the mechanical properties, may
significantly increase the level of radioactivity on the emulsions. A detailed
study was made in order to choose a lead alloy with good mechanical properties
and an appropriate packing technique so as to have a low enough effective
radioactivity.Comment: 19 pages, 11 figure
HE-LHC: The High-Energy Large Hadron Collider – Future Circular Collider Conceptual Design Report Volume 4
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries
FCC-ee: The Lepton Collider: Future Circular Collider Conceptual Design Report Volume 2
In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh), which could, successively, be installed in the same 100 km tunnel. The scientific capabilities of the integrated FCC programme would serve the worldwide community throughout the 21st century. The FCC study also investigates an LHC energy upgrade, using FCC-hh technology. This document constitutes the second volume of the FCC Conceptual Design Report, devoted to the electron-positron collider FCC-ee. After summarizing the physics discovery opportunities, it presents the accelerator design, performance reach, a staged operation scenario, the underlying technologies, civil engineering, technical infrastructure, and an implementation plan. FCC-ee can be built with today’s technology. Most of the FCC-ee infrastructure could be reused for FCC-hh. Combining concepts from past and present lepton colliders and adding a few novel elements, the FCC-ee design promises outstandingly high luminosity. This will make the FCC-ee a unique precision instrument to study the heaviest known particles (Z, W and H bosons and the top quark), offering great direct and indirect sensitivity to new physics
FCC Physics Opportunities: Future Circular Collider Conceptual Design Report Volume 1
We review the physics opportunities of the Future Circular Collider, covering its e+e-, pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and strong interactions, the top quark and flavour, as well as phenomena beyond the Standard Model. We highlight the synergy and complementarity of the different colliders, which will contribute to a uniquely coherent and ambitious research programme, providing an unmatchable combination of precision and sensitivity to new physics
- …