arXiv subjects

Xue-Yao Zhang

Publications and source records attributed to Xue-Yao Zhang.

3 recordsLinked to original sources

arXiv2017

Application of SNiPER framework to BESIII physics analysis

A fast physics analysis framework has been developed based on SNiPER to process the increasingly large data sample collected by BESIII. In this framework, a reconstructed event data model with SmartRef is designed to improve the speed of Input/Output operations, and necessary physics analysis tools are migrated from BOSS to SNiPER. A real physics analysis $e^{+}e^{-} \rightarrow π^{+}π^{-}J/ψ$ is used to test the new framework, and achieves a factor of 10.3 improvement in Input/Output speed compared to BOSS. Further tests show that the improvement is mainly attributed to the new reconstructed event data model and the lazy-loading functionality provided by SmartRef.

hep-ex↗

arXiv2016

Performance of new 8-inch photomultiplier tube used for the Tibet muon-detector array

A new hybrid experiment has been constructed to measure the chemical composition of cosmic rays around the "knee" in the wide energy range by the Tibet AS$γ$ collaboration at Tibet, China, since 2014. They consist of a high-energy air-shower-core array (YAC-II), a high-density air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD). In order to obtain the primary proton, helium and iron spectra and their "knee" positions in the energy range lower than $10^{16}$ eV, each of PMTs equipped to the MD cell is required to measure the number of photons capable of covering a wide dynamic range of 100 - $10^{6}$ photoelectrons (PEs) according to Monte Carlo simulations. In this paper, we firstly compare the characteristic features between R5912-PMT made by Japan Hamamatsu and CR365-PMT made by Beijing Hamamatsu. This is the first comparison between R5912-PMT and CR365-PMT. If there exists no serious difference, we will then add two 8-inch-in-diameter PMTs to meet our requirements in each MD cell, which are responsible for the range of 100 - 10000 PEs and 2000 - 1000000 PEs, respectively. That is, MD cell is expected to be able to measure the number of muons over 6 orders of magnitude.

physics.ins-det↗

arXiv2008

A possible signature of new physics at BES-III

The recent observations of the purely leptonic decay $\Ds \to μ^+ ν_μ$ and $τ^+ν_τ$ at CLEO-c and $B$ factory may allow a possible contribution from a charged Higgs boson. One such measurement of the decay constant $f_{D_s}$ differs from the most precise unquenched lattice QCD calculation by 4 $σ$ level. Meanwhile, the measured ratio, ${\cal BR}(\Ds \to μ^+ ν_μ)$ / ${\cal BR}(\Dp \to μ^+ ν_μ)$, is larger than the standard model prediction at 2.0$σ$ level. We discuss that the precise measurement of the ratio ${\cal BR}(\Ds \to μ^+ ν_μ)$ / ${\cal BR}(\Dp \to μ^+ ν_μ)$ at BES-III will shed light on the presence of new intermediate particles by comparing the theoretical predictions, especially, the predictions of high precise unquenched lattice QCD calculation.

hep-ex↗