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A data-driven approach to π^0,η and η＇ single and double Dalitz decays

Chinese Physics C 2018年第2期42卷 89-105页

作者： Rafel Escribano Sergi Gonzàlez-Solís Crup de Fisica Tebrica Departament de Fisica Universitat Autbnoma de Barcelona E-08193 Bellaterra (Barcelona) Spain Institut de Fisica d'Altes Energies (IFAE) The Barcelona Institute of Science and Technology (BIST) Campus UAB E-08193 Bellaterra (Barcelona) Spain CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

The dilepton invariant mass spectra and integrated branching ratios of the single and double Dalitz decays P→l^＋l^-γ and P→l^＋l^-l^＋l^-（P=π^0,η,η＇;l=e or μ） are predicted by means of a data-driven approach based on the use of rational approximants applied to π^0,η and η＇ transition form factor experimental data in the space-like region.

关键词： electromagnetic processes and properties phenomenological models transition form factor

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Real-time forecasts of the COVID-19 epidemic in China from February 5th to February 24th,2020

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Infectious Disease Modelling 2020年第1期5卷 256-263页

作者： K.Roosa Y.Lee R.Luo A.Kirpich R.Rothenberg J.M.Hyman P.Yan G.Chowell Department of Population Health Sciences School of Public HealthGeorgia State UniversityAtlantaGAUSA Department of Mathematics Center for Computational ScienceTulane UniversityNew OrleansLAUSA Infectious Disease Prevention and Control Branch Public Health Agency of CanadaOttawaCanada

The initial cluster of severe pneumonia cases that triggered the COVID-19 epidemic was identified inWuhan,China in December *** early cases of the disease were linked to a wet market,human-to-human transmission has driven the rapid spread of the virus throughout *** Chinese government has implemented containment strategies of city-wide lockdowns,screening at airports and train stations,and isolation of suspected patients;however,the cumulative case count keeps growing every *** ongoing outbreak presents a challenge for modelers,as limited data are available on the early growth trajectory,and the epidemiological characteristics of the novel coronavirus are yet to be fully *** use phenomenological models that have been validated during previous outbreaks to generate and assess short-term forecasts of the cumulative number of confirmed reported cases in Hubei province,the epicenter of the epidemic,and for the overall trajectory in China,excluding the province of *** collect daily reported cumulative confirmed cases for the 2019-nCoV outbreak for each Chinese province from the National Health Commission of ***,we provide 5,10,and 15 day forecasts for five consecutive days,February 5th through February 9th,with quantified uncertainty based on a generalized logistic growth model,the Richards growth model,and a sub-epidemic wave *** most recent forecasts reported here,based on data up until February 9,2020,largely agree across the three models presented and suggest an average range of 7409e7496 additional confirmed cases in Hubei and 1128e1929 additional cases in other provinces within the next five *** also predict an average total cumulative case count between 37,415 and 38,028 in Hubei and 11,588e13,499 in other provinces by February 24,*** estimates and uncertainty bounds for both Hubei and other provinces have remained relatively stable in the last three reporting dates(February 7th e 9th).We also observe that

关键词： COVID-19 Coronavirus China Real-time forecasts phenomenological models

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Estimating epidemic exponential growth rate and basic reproduction number

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Infectious Disease Modelling 2020年第1期5卷 129-141页

作者： Junling Ma Department of Mathematics and Statistics University of VictoriaVictoriaBCV8W 2Y2Canada

The initial exponential growth rate of an epidemic is an important measure of the severeness of the epidemic,and is also closely related to the basic reproduction *** the growth rate from the epidemic curve can be a challenge,because of its decays with *** fast epidemics,the estimation is subject to over-fitting due to the limited number of data points available,which also limits our choice of models for the epidemic *** discuss the estimation of the growth rate using maximum likelihood method and simple models.

关键词： Epidemic curve Exponential growth rate Maximum likelihood estimation phenomenological models

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