北京谱仪物理分析中联合拟合的系统误差方法（英文）
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摘要
在高能物理的数据分析中,经常用联合拟合的方法从多数据样本中提取参数.联合拟合可以利用最多的信息,将不同样本之间的关联考虑进来,拟合结果是无偏的,能直接得到综合的系统误差.在联合拟合中,不同的数据样本之间的关联会直接影响拟合结果.利用北京谱仪的软件产生一个蒙特卡洛方法模拟的样本来展现如何在拟合程序中增加更多限制条件和如何计算出综合了多个样本的联合拟合结果的系统误差.
In the data analysis of high energy physics, multi-data sets are often used to extract parameters by the simultaneous fit, which makes use of the maximum information and takes the correlations into account so that the fitting results are unbiased and the combined systematic uncertainties can be got directly. In the simultaneous fit, however, the correlations among the multi-data sets will affect the final results and should be considered carefully. In this article, a Monte Carlo simulated sample is generated using a BESIII software and it is used to show how to add more constrains in the fit procedure and calculated the combined systematic uncertainties contribute to the simultaneous fit of the multi-data sets.
In the data analysis of high energy physics, multi-data sets are often used to extract parameters by the simultaneous fit, which makes use of the maximum information and takes the correlations into account so that the fitting results are unbiased and the combined systematic uncertainties can be got directly. In the simultaneous fit, however, the correlations among the multi-data sets will affect the final results and should be considered carefully. In this article, a Monte Carlo simulated sample is generated using a BESIII software and it is used to show how to add more constrains in the fit procedure and calculated the combined systematic uncertainties contribute to the simultaneous fit of the multi-data sets.
引文
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2 BESIII Collaboration.Design and construction of the BESIII detector[J].Nucl Instrum Methods Phys Res Sect A,2010,614:345-399.
3 BESIII Collaboration.Observation of e+e-→η'J/ψat center-of-mass energies between 4.189 and 4.600 GeV[J].Phys Rev D,2016,94:032009.
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7 BESIII Collaboration.Search for hadronic transitionχc J→ηCπ+π-and observation ofχc J→KKˉπππ[J].Phys Rev D,2013,87:012002.
8 BESIII Collaboration.Measurement of the e+e-→ηJ/ψcross section and search for e+e-→π0J/ψat center-ofmass energies between 3.810 and 4.600 GeV[J].Phys Rev D,2015,91:112005.