Search results for "measurement theory"
showing 10 items of 18 documents
First measurement of the W-boson mass in run II of the Tevatron.
2007
7 pages, 4 figures.-- PACS nrs.: 14.70.Fm; 13.38.Be; 13.85.Qk.-- ISI Article Identifier: 000250140600014.-- ArXiv pre-print available at: http://arxiv.org/abs/0707.0085.-- et al.
3/4-efficient Bell measurement with passive linear optics and unentangled ancillae
2014
It is well known that an unambiguous discrimination of the four optically encoded Bell states is possible with a probability of $50\%$ at best, when using static, passive linear optics and arbitrarily many vacuum mode ancillae. By adding unentangled single-photon ancillae, we are able to surpass this limit and reach a success probability of at least $75\%$. We discuss the error robustness of the proposed scheme and a generalization to reach a success probability arbitrarily close to $100\%$.
Discrete-mathematical approach to formal description of measurement procedure
1996
The discrete-mathematical model of measurement procedure is developed for facilitating the description of measurements in both quantitative and qualitative scales. On the basis of this model the Measurement Problem is formulated. It is shown that the problem can be considered, in the general case, as one of the discrete optimization problems. The suggested approach brings closer the concepts of a computing algorithm and measurement procedure so that it permits the application of similar tools for the analysis and development of both of them.
A PC-based wattmeter for high accuracy power measurements
2010
This paper proposes the use of a commercial data acquisition board (DAQ) connected to a common personal computer for high accuracy power measurements. In the paper the set up of the PC-based wattmeter is described and an experimental evaluation of its metrological performances is made by means of the comparison with a simultaneous coherent digital sampling wattmeter realized with two high-precision DMMs Hewlett Packard Model 3458 A. In both cases the power source is a Fluke 6100A/E electrical power standard. © 2010 IEEE.
Development of a high-accuracy PC-based wattmeter with commercial data acquisition boards
2011
This paper presents the development of a high accuracy sampling wattmeter, which makes use of two commercial data acquisition boards (DAQs) connected to a common personal computer. Commercial software is also used for data processing and implementation of the virtual instrument. The set up of the PC-based wattmeter is described and a preliminary evaluation of its metrological performances is made by means of two series of experimental tests, which were carried out with an electric power standard and a high performance multifunction calibrator. © 2011 IEEE.
Cross-country comparisons of trends in adolescent psychosomatic symptoms : a Rasch analysis of HBSC data from four Nordic countries
2018
BACKGROUND: To analyse the psychometric properties of the HBSC Symptom Checklist (HBSC-SCL) on psychosomatic symptoms with a focus on the operating characteristics of the items, and on the impacts of measurement distortions on the comparisons of person measures across time and between countries.METHODS: Data were collected in 1993/94, 1997/98, 2001/02, 2005/06, 2008/09, 2013/14 in Denmark, Finland, Norway and Sweden as part of the Health Behaviour in School-aged Children (HBSC) study. Data comprised 116,531 students 11, 13 and 15 years old. Rasch analysis was conducted of the HBSC-SCL consisting of eight items with a focus on Differential Item Functioning (DIF) and item threshold ordering. …
Some structural properties of a formal model of measurement procedure
1996
Three kinds of a model structure for a measurement procedure are analyzed, i.e. one-cyclic, tree-like and multicyclic. For a multicyclic structure a method of the choice of the optimal strategy for partitioning the uncertainty interval is constructed. An example of a measurement procedure using the suggested strategy is given. Some specific cases of the strategies under different initial conditions are discussed.
Observation and Mass Measurement of the BaryonΞb−
2007
We report the observation and measurement of the mass of the bottom, strange baryon $\Xi^-_b$ through the decay chain $\Xi^-_b \to J/\psi \Xi^-$, where $J/\psi \to \mu^+ \mu^-$, $\Xi^- \to \Lambda \pi^-$, and $\Lambda \to p \pi^-$. Evidence for observation is based on a signal whose probability of arising from the estimated background is 6.6 x 10^{-15}, or 7.7 Gaussian standard deviations. The $\Xi^-_b$ mass is measured to be $5792.9\pm 2.5$ (stat.) $\pm 1.7$ (syst.) MeV/$c^2$.
Interference Effects in Photodetachment of F- in a Strong Circularly Polarized Laser Pulse
2007
A numerical simulation of photodetachment of F{sup -} by a circularly polarized laser pulse has been accomplished by using a Keldysh-type approach. The numerical results are in agreement with measurements of photoelectron energy spectra recently reported in the literature. The features exhibited by the spectra are traced back to quantum interference effects, in the same spirit as in a double-slit experiment in the time doma0008.
Interaction-free evolution in the presence of time-dependent Hamiltonians
2015
The generalization of the concept of interaction-free evolutions (IFE) [A. Napoli, {\it et al.}, Phys. Rev. A {\bf 89}, 062104 (2014)] to the case of time-dependent Hamiltonians is discussed. It turns out that the time-dependent case allows for much more rich structures of interaction-free states and interaction-free subspaces. The general condition for the occurrence of IFE is found and exploited to analyze specific situations. Several examples are presented, each one associated to a class of Hamiltonians with specific features.