Bose-Einstein and colour interference in W-pair decays

We study effects on the W mass measurements at LEP2 from non-perturbative interference effects in the fully hadronic decay channel. Based on a model for Bose-Einstein interference, which is in agreement with LEP1 data, we argue that there are no Bose-Einstein correlations between bosons coming from the different W's. For small reconnection probabilities we rule out the possible experimental signal of colour interference at LEP2, suggested in [1]. The conclusions from this paper are that the theoretical uncertainties in the W mass determination should be smaller than the experimental statistical error.

The precise measurement of mass is one of the more challenging measurement requirements that materials scientists must deal with. The use of electronic balances has become so widespread and routine that the accurate measurement of mass is often taken for granted. While government institutions such as the National Institutes of Standards and Technology (NIST) and state metrology offices enforce controls in the industrial and legal sectors, no such rigors generally affect the research laboratory. The process of peer review seldom makes assessments of the accuracy of an underlying measurement involved unless an egregious problem is brought to the surface by the reported results. In order to ensure reproducibility, any measurement process in a laboratory should be subjected to a rigorous and frequent calibration routine. This article will describe the options available to the investigator for establishing and executing such a routine; it will define the underlying terms, conditions, and standards, and will suggest appropriate reporting and documenting practices. The measurement of mass, which is a fundamental measurement of the amount of material present, will constitute the bulk of the discussion. However, the measurement of derived properties, particularly density, will also be discussed, as well as some indirect techniques used particularly by materials scientists in the determination of mass and density, such as the quartz crystal microbalance for mass measurement and the analysis of diffraction data for density determination.

An interferometric study of the anhydrous nuclear mass of exfoliated cells from experimental cervical cancer

After several decades of a dramatic development Penning-trap mass spectrometry now demonstrates unprecedented precision and sensitivity in measurements of the masses of a broad range of nuclides for various aspects of fundamental physics. This article reviews one facet of such mass measurements—a contribution of Penning-trap mass spectrometry to experiments on studies of neutrinos. These studies encompass the determination of the neutrino mass, the search for sterile and relic neutrinos and the search for neutrinoless double electron capture in order to determine the type of neutrinos as well as to check the conservation law of the total lepton number.

Low energy SUSY confronted with new measurements of W-boson mass and muon [formula omitted

We analyze the result of precise measurement of the Casimir force between bodies covered with gold. The values of the parameters used to extrapolate the gold dielectric function to low frequencies are very important and discussed in detail. The finite temperature effect is shown to exceed considerably the experimental errors. The upper limit on the force is found which is smaller than the measured force. Many experimental and theoretical uncertainties were excluded with gold covering and we conclude that, possibly, a new force has been detected at small separations between bodies.

Principles for determining moisture content and mass of individual peanut kernels by microwave resonator measurements are discussed, and data are presented showing the application of these principles. By measuring the shift in the resonant frequency and the change in the cavity transmission characteristics when a peanut is inserted into the cavity, it is possible to obtain the moisture content of the kernel independent of its mass and apparently independent of peanut type, as far as Runner and Virginia market types are concerned. It is also possible to determine the kernel mass independent of kernel shape simultaneously with the moisture determination. Moisture contents in the range from 4 to 14%, wet basis, were determined with an uncertainty of 0.9% moisture, and the uncertainty in the mass determination was less than 0.05 g.

Previous work by Castor, Abbott, and Klein (1975) presented a self-consistent model of a steady-state stellar wind. They also showed qualitatively that for O stars at least a static atmosphere could not exist. This paper extends that result by calculating in detail the minimum luminosity as a function of effective temperature required for the line radiation force to exceed gravity. Within the observational and theoretical uncertainty there is a one-to-one correspondence between a star's calculated ability to self-initiate a stellar wind by radiation pressure alone and the observed presence of outflowing material in the UV resonance lines.

The experimental determination of average mass by mass spectrometry is limited for large molecules due to the negative bias introduced by the natural distribution of isotopic abundances. This results in the measurement of the top-of-centroid (ToC) as opposed to the true centroid. We have developed a practical correction factor that is applied to the ToC measurement to largely remove the systematic bias introduced by nature. The correction factor is calculated easily using the average molecular mass (<100 kDa) of the analyte molecule and the full-width half maximum resolving power (<3,500) of the measurement. In addition, an approach to calculating resolving power is described that accurately predicts resolving power achievable for Fourier transform ion cyclotron resonance (FT-ICR) mass analysis of large molecules. A combination of internal calibration with a dual-electrospray source and application of the correction factor to average mass measurements improved the mass error from 192.5 to -35.0 ppm for a 44 kDa PCR amplicon.

As a key sensor, radar plays an important role in obtaining war information. However, radar will be affected by the deteriorating electromagnetic environment on the battlefield. Therefore, it is necessary to carry out electromagnetic interference effect experiments to improve the anti-interference ability. In the electromagnetic interference experiment of the radar TR component, the signal output from the signal generator passes through the power amplifier, the transmitting antenna and the receiving antenna, and then is applied to the TR component. In the experiment, to obtain a certain size of interference signal acting on the TR component, it is often necessary to manually adjust the output signal strength of the signal generator repeatedly through human experience. The experimental process is complicated, and the experimental error is large. Therefore, it will make the experiment more convenient and accurate to achieve the desired interference signal size on the TR component by accurately predicting the output signal strength value of the signal generator, which has important practical significance. This paper proposes an IGWO-SVR based signal generator output signal strength prediction model, which includes Improved Grey Wolf Optimizer (IGWO) and Support Vector Regression (SVR) algorithms. IGWO is a new swarm optimization algorithm proposed in this paper. By improving the convergence factor a and the final position of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\omega $ </tex-math></inline-formula> wolf, IGWO solves the problems that the traditional GWO algorithm easily falls into local optimum and the convergence speed is slow. IGWO is used to optimize two hyperparameters of SVR (penalty coefficient C and kernel parameter <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula>). SVR is used to predict the output signal strength value of the signal generator. To prove the validity of the IGWO-SVR, comparison experiments are made between the IGWO-SVR and 20 other models. The real data obtained from the experiments of electromagnetic interference effect by irradiation method are selected as the experimental data. Mean Absolute Error (MAE), Mean Squared Error (MSE), and Fitting Degree R Squared <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(R^{2})$ </tex-math></inline-formula> are used to evaluate the overall performance of the models. Through comparative experiments, the MAE of the IGWO-SVR model is 1.1481, MSE is 2.6679, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$R^{2}$ </tex-math></inline-formula> is 0.9430, and its performance in various evaluation indexes is better than other models.

The stoichiometry of yeast V(1)-ATPase peripheral stalk subunits E and G was determined by two independent approaches using mass spectrometry (MS). First, the subunit ratio was inferred from measuring the molecular mass of the intact V(1)-ATPase complex and each of the individual protein components, using native electrospray ionization-MS. The major observed intact complex had a mass of 593,600 Da, with minor components displaying masses of 553,550 and 428,300 Da, respectively. Second, defined amounts of V(1)-ATPase purified from yeast grown on (14)N-containing medium were titrated with defined amounts of (15)N-labeled E and G subunits as internal standards. Following protease digestion of subunit bands, (14)N- and (15)N-containing peptide pairs were used for quantification of subunit stoichiometry using matrix-assisted laser desorption/ionization-time of flight MS. Results from both approaches are in excellent agreement and reveal that the subunit composition of yeast V(1)-ATPase is A(3)B(3)DE(3)FG(3)H.

In this paper, we propose a frequency-domain estimating and time-domain compensating tone interference (TI) cancellation algorithm for direct-sequence spread-spectrum systems. In the previous works, the interference signal is estimated and compensated in the frequency-domain and then, with IFFT (inverse fast Fourier transform), the compensated frequency-domain signal is transformed to the time-domain signal for the remaining receiver operations. Unlike the previous works, the proposed algorithm estimate the TI signals in frequency-domain and compensates the resulting estimated TI signals in time-domain and thus, does not requires IFFT. Hence, the proposed algorithm not only shows the virtually identical performance but also requires lower hardware complexity compared to the schemes proposed in the previous works.

A measurement of the electroweak couplings of up and down type quarks using final state photons in hadronic Z0 decays

The mean depth (a), the mean width (b) and the relative concentration (c) of an unknown distribution of foreign atoms in bulk material can be determined by relative x-ray yield measurements. It is shown by means of a set of case studies for rectangular distributions of foreign Cu-atoms in Ag-bulk to which extent experimental x-ray yield errors, and errors in the theoretical description of the x-ray production process and the stopping of projectiles contribute to errors in the result. The theoretical description uses the ECPSSR theory and takes experimental deviation from this theory, energy loss straggling and multiple scattering into account.

We study the theoretical uncertainties in the determination of the top-quark mass using next-to-leading-order (NLO) generators, that describe the top-quark decay at different levels of accuracy, interfaced to parton showers (PS). Specifically we consider one generator that implements NLO corrections only in the production dynamics, one that also takes them into account in the top-quark decay in the narrow width approximation (NWA) and one that implements them exactly, including finite-width and interference effects. We aim at assessing the errors in top-mass determinations of purely theoretical origin. We do so by measuring relative peak position shifts of $Wb$-jet mass distributions. Besides the theoretical errors due to the use of less accurate NLO+PS generators, we also explore uncertainties related to shower and modelling of non-perturbative effects by comparing the results obtained by interfacing our generators to both Pythia and Herwig shower Monte Carlos (SMCs).