scholarly journals Internal Cumulants for Femtoscopy with Fixed Charged Multiplicity

2013 ◽  
Vol 2013 ◽  
pp. 1-22
Author(s):  
H. C. Eggers ◽  
B. Buschbeck
Keyword(s):  
Multiplicity Distribution ◽  
Reference Sample ◽  
Higher Order ◽  
Correction Factors ◽  
Charged Multiplicity ◽  
Detailed Understanding ◽  
Null Result ◽  
Careful Specification ◽  
Multiplicity Distributions ◽  
Reference Samples

A detailed understanding of all effects and influences on higher-order correlations is essential. At low charged multiplicity, the effect of a non-Poissonian multiplicity distribution can significantly distort correlations. Evidently, the reference samples with respect to which correlations are measured should yield a null result in the absence of correlations. We show how the careful specification of desired properties necessarily leads to an average-of-multinomials reference sample. The resulting internal cumulants and their averaging over several multiplicities fulfill all requirements of correctly taking into account non-Poissonian multiplicity distributions as well as yielding a null result for uncorrelated fixed-Nsamples. Various correction factors are shown to be approximations at best. Careful rederivation of statistical variances and covariances within the frequentist approach yields errors for cumulants that differ from those used so far. We finally briefly discuss the implementation of the analysis through a multiple event buffer algorithm.

CHARGED MULTIPLICITY DISTRIBUTION IN RELATIVISTIC HEAVY-ION COLLISIONS

2009 ◽  
Vol 18 (09) ◽  
pp. 1929-1944 ◽  
Author(s):  
SHAFIQ AHMAD ◽  
M. AYAZ AHMAD ◽  
M. TARIQ ◽  
M. ZAFAR
Keyword(s):  
Heavy Ion Collisions ◽  
Nuclear Emulsion ◽  
Multiplicity Distribution ◽  
Heavy Ion ◽  
Universal Function ◽  
Relativistic Heavy Ion Collisions ◽  
Medium Energy ◽  
Charged Multiplicity ◽  
Ion Collisions ◽  
Multiplicity Distributions

The experimental results of multiplicity distributions of grey and relativistic shower particles emitted in the interactions of 28 Si and 12 C ions at 4.5 A GeV /c with nuclear emulsion are reported. The study of the multiplicity distributions of relativistic shower particles and medium energy target-associated protons produced in heavy-ion collisions seems to observe the semi-inclusive KNO scaling. A simplified universal function has been used to represent the experimental data.

Multiplicity distributions in proton–neutron interactions at 400 GeV/c

1983 ◽  
Vol 61 (4) ◽  
pp. 523-531 ◽  
Author(s):  
D. K. Bhattacharjee ◽  
S. K. Ray ◽  
P. Sarkar ◽  
T. Roy
Keyword(s):  
Multiplicity Distribution ◽  
Bubble Chamber ◽  
Hydrogen Bubble ◽  
Double Scattering ◽  
Hydrogen Bubble Chamber ◽  
Charged Multiplicity ◽  
Distinctive Features ◽  
Distribution Parameters ◽  
Average Fraction ◽  
Multiplicity Distributions

We present a study on the charged multiplicity distribution in proton–neutron (pn) interactions at 400 GeV/c from the data on an exposure of a Fermilab 30-in. deuterium bubble chamber to 400 GeV/c protons. The pn and pp distributions were extracted through an empirical model to correct for double scattering in deuterium. The overall average fraction of the double scattered event is 0.128 ± 0.011. The resulting pn and pp multiplicity distributions give average multiplicities of 8.48 ± 0.10 and 8.99 ± 0.12 respectively. The fraction of pd events which occur off the neutron is 0.52 ± 0.02. The extracted pp distribution parameters are compared with those from the hydrogen bubble chamber (HBC) experiments. Distinctive features of extracted pn distribution are discussed.

scholarly journals A verified genomic reference sample for assessing performance of cancer panels detecting small variants of low allele frequency

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Wendell Jones ◽  
Binsheng Gong ◽  
Natalia Novoradovskaya ◽  
Dan Li ◽  
Rebecca Kusko ◽  
...  
Keyword(s):  
Quality Control ◽  
Allele Frequency ◽  
Liquid Biopsy ◽  
Limit Of Detection ◽  
Reference Sample ◽  
Digital Pcr ◽  
Detection Sensitivity ◽  
Analytical Accuracy ◽  
And Performance ◽  
Reference Samples

Abstract Background Oncopanel genomic testing, which identifies important somatic variants, is increasingly common in medical practice and especially in clinical trials. Currently, there is a paucity of reliable genomic reference samples having a suitably large number of pre-identified variants for properly assessing oncopanel assay analytical quality and performance. The FDA-led Sequencing and Quality Control Phase 2 (SEQC2) consortium analyze ten diverse cancer cell lines individually and their pool, termed Sample A, to develop a reference sample with suitably large numbers of coding positions with known (variant) positives and negatives for properly evaluating oncopanel analytical performance. Results In reference Sample A, we identify more than 40,000 variants down to 1% allele frequency with more than 25,000 variants having less than 20% allele frequency with 1653 variants in COSMIC-related genes. This is 5–100× more than existing commercially available samples. We also identify an unprecedented number of negative positions in coding regions, allowing statistical rigor in assessing limit-of-detection, sensitivity, and precision. Over 300 loci are randomly selected and independently verified via droplet digital PCR with 100% concordance. Agilent normal reference Sample B can be admixed with Sample A to create new samples with a similar number of known variants at much lower allele frequency than what exists in Sample A natively, including known variants having allele frequency of 0.02%, a range suitable for assessing liquid biopsy panels. Conclusion These new reference samples and their admixtures provide superior capability for performing oncopanel quality control, analytical accuracy, and validation for small to large oncopanels and liquid biopsy assays.

SOME CHARACTERISTICS OF THE COMPOUND MULTIPLICITY IN HIGH-ENERGY NUCLEUS–NUCLEUS INTERACTIONS

2011 ◽  
Vol 20 (08) ◽  
pp. 1735-1754 ◽  
Author(s):  
M. MOHERY ◽  
M. ARAFA
Keyword(s):  
Experimental Data ◽  
Impact Parameter ◽  
Mass Number ◽  
Multiplicity Distribution ◽  
High Energy ◽  
Projectile Nucleus ◽  
Target Mass ◽  
Compound Multiplicity ◽  
Multiplicity Distributions ◽  
The Impact

The present paper deals with the interactions of 22 Ne and 28 Si nuclei at (4.1–4.5)A GeV /c with emulsion. Some characteristics of the compound multiplicity nc given by the sum of the number of shower particles ns and grey particles ng have been investigated. The present experimental data are compared with the corresponding ones calculated according to modified cascade evaporation model (MCEM). The results reveal that the compound multiplicity distributions for these two reactions are consistent with the corresponding ones of MCEM data. It can also be seen that the peak of these distributions shifts towards a higher value of nc with increasing projectile mass. It may further be seen that the compound multiplicity distributions becomes broader with increasing target size and its width increases with the size of the projectile nucleus. In addition, it has been found that the MCEM can describe the compound multiplicity characteristics of the different projectile, target and the correlation between different emitted particles. The values of average compound multiplicity increase with increasing mass of the projectile. Furthermore, it is observed that while the value of 〈nc〉 depends on the mass number of the projectile Ap and the target mass number At, the value of the ratio 〈nc〉/D(nc) seems to be independent of Ap and At. The impact parameter is found to affect the shape of the compound multiplicity distribution. Finally, the dependence of the average compound multiplicity on the numbers of grey and black particles, and the sum of them, is obvious. The values of the slope have been found to be independent of the projectile nucleus.

GLOBAL PROPERTIES OF MULTIPLICITY DISTRIBUTIONS AND MULTIPLICITY CORRELATIONS IN e+e- ANNIHILATION AT LEP ENERGIES AS A MEASURE OF COHERENT DYNAMICS

1991 ◽  
Vol 06 (01) ◽  
pp. 55-60 ◽  
Author(s):  
SAUL BARSHAY
Keyword(s):  
Multiplicity Distribution ◽  
Dynamical Processes ◽  
Global Properties ◽  
Coherent Dynamics ◽  
Multiplicity Distributions

We study the possibility of the observable emergence of dynamical forward-backward multiplicity correlations among produced charge hadrons, and of a steadily broadening multiplicity distribution in e+e- annihilation at LEP. It is important to measure three related global properties. These reflect coherent dynamical processes in and among jets.

scholarly journals Composite Materials Based on Henequen Fiber as a Thermal Barrier in the Automotive Sector

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
J. M. Olivares-Ramírez ◽  
A. Dector ◽  
A. Duarte-Moller ◽  
D. Ortega Díaz ◽  
Diana Dector ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Carbon Fiber ◽  
Solar Radiation ◽  
High Performance ◽  
Natural Fiber ◽  
Reference Sample ◽  
Thermal Barrier ◽  
Transfer Mechanisms ◽  
Reference Samples

Currently, the automotive industry has made great advances in the incorporation of materials such as carbon fiber in high-performance cars. One of the main problems of these vehicles is warming, which is generated inside due to the heat transfer produced by solar radiation falling on the car, mainly on the roof. This research proposes the preparation of a composite material containing henequen natural fiber as a thermal barrier to be used as the roof of the car. In this research, 35 different laminates of 5 layers were prepared, combining carbon fiber, henequen natural fiber, fiberglass, and additives such as resin + Al2O3 or resin + Al. Reference samples were taken from stainless steel and one reference sample was extracted from the roof of the car. Considering the solar radiation and the heat transfer mechanisms, the temperature of the surface exposed to solar radiation was determined. The thermal conductivity of the 37 samples was determined, and the experimental results showed that the thermal conductivity of the steel with which the roof of the car is manufactured was 13.43 W·m−1·K−1 and that of the proposed laminate was 5.22 W·m−1·K−1, achieving a decrease in the thermal conductivity by 61.13%. Using the temperature and thermal conductivity data, the simulation (ANSYS) of the thermal system was performed. The results showed that the temperature inside the car with the carbon steel, which is currently used to manufacture high-performance cars, would be 62.34°C, whereas that inside the car with the proposed laminate would be 44.96°C, achieving a thermal barrier that allows a temperature difference of 17.38°C.

Precision Estimates in Clinical Chemistry

1967 ◽  
Vol 13 (7) ◽  
pp. 595-607 ◽  
Author(s):  
G N Bowers ◽  
M L Kelley ◽  
R B McComb
Keyword(s):  
Human Serum ◽  
Clinical Chemistry ◽  
Chemical Reactivity ◽  
Reference Sample ◽  
Serum Enzyme ◽  
Electrophoretic Migration ◽  
Alkaline Denaturation ◽  
The Stability ◽  
And Control ◽  
Reference Samples

Abstract The precision of replicate analyses for alkaline phosphataseactivity measured on a survey reference sample was extremely poor. The reference sample's enzyme itself became suspect and was demonstrated to be sensitive to alkaline denaturation-in sharp contrast to the stability of the alkaline phosphatasesfound in human serum. The stability and chemical reactivity of the phosphatases present in this reference sample and in pooled frozen human serum, as well as those found in 4 partially purified nonhuman preparations and 4 commercial serum control materials, were investigated with regard to heat and alkaline denaturation, electrophoretic migration, and inhibition by phosphate, EDTA, and L-pheflylalanine. It was concluded that criteria of stability and chemical reactivity, as well as more detailed information concerning the source of enzymes utilized in reference samples and control materials, are needed. On the basis of these studies, reliance on commercial serum enzyme control materials as an enzyme "standard" cannot be endorsed.

MULTIPLICITY DISTRIBUTIONS IN LIMITED PSEUDORAPIDITY INTERVALS

1986 ◽  
Vol 01 (01) ◽  
pp. 15-21 ◽  
Author(s):  
C.S. LAM ◽  
M.S. ZAHIR
Keyword(s):  
Experimental Data ◽  
Multiplicity Distribution ◽  
Number Of Clusters ◽  
Total Multiplicity ◽  
Multiplicity Distributions

We calculate the multiplicity distributions in fixed pseudorapidity intervals |η|≤ηc for [Formula: see text] collisions at [Formula: see text] GeV from the total multiplicity distribution. Agreement with experimental data is good where expected. This calculation may be regarded as giving a relation between the number of clusters lying inside |η|≤ηc and the partition temperature Tp(N) introduced by Chou, Yang and Yen for N produced particles.

Confidence assessment and interval prediction for multi-input model via grey system theory

2018 ◽  
Vol 8 (1) ◽  
pp. 69-83 ◽  
Author(s):  
Haoliang Wang ◽  
Xiwang Dong ◽  
Qingdong Li ◽  
Zhang Ren
Keyword(s):  
Confidence Interval ◽  
Correlation Coefficient ◽  
Calculation Method ◽  
Reference Sample ◽  
Prediction Method ◽  
Calculation Methods ◽  
Content Type ◽  
Interval Prediction ◽  
Confidence Value ◽  
Reference Samples

Purpose By using small reference samples, the calculation method of confidence value and prediction method of confidence interval for multi-input system are investigated. The purpose of this paper is to offer effective assessing methods of confidence value and confidence interval for the simulation models used in establishing guidance and control systems. Design/methodology/approach In this paper, first, an improved cluster estimation method is proposed to guide the selection of the small reference samples. Then, based on analytic hierarchy process method, the new calculation method of the weight of each reference sample is derived. By using the grey relation analysis method, new calculation methods of the correlation coefficient and confidence value are presented. Moreover, the confidence interval of the sample awaiting assessment is defined. A new prediction method is derived to obtain the confidence interval of the sample awaiting assessment which has no reference sample. Subsequently, by using the prediction method and original small reference samples, Bootstrap resampling method is used to obtain more correlation coefficients for the sample to reduce the probability of abandoning the true. Findings The grey relational analysis is used in assessing the confidence value and interval prediction. The numerical simulations are presented to demonstrate the effectiveness of the theoretical results. Originality/value Based on the selected small reference samples, new calculation methods of the correlation coefficient and confidence value are presented to assess the confidence value of model awaiting assessment. The calculation methods of maximum confidence interval, expected confidence interval and other required confidence intervals are presented, which can be used in assessing the validities of controller and guidance system obtained from the model awaiting assessment.

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