超级陶粲装置（STCF）是未来计划的高亮度正负电子对撞机，将是目前正在运行的北京正负电子对撞机对撞亮度的100倍。利用亮度为2.5 fb-1质心能量在7 GeV的e+e-→qq模拟样本，研究STCF实验上电子湮灭产生单举带电π介子对或带电K介子对的Collins不对称度测量的精度。在预期积分亮度为1 ab-1（预期在STCF上采集一年的数据量）的情况下，预计ππX过程的Collins不对称度测量精度为10-4量级，KKX的测量精度为10-3量级。研究发现测量的不对称度的系统误差受本底水平与K-π误鉴别影响很大，因此在未来的STCF实验上采用契伦科夫探测器提高高动量的K-π鉴别能力对提高Collins碎裂函数测量精度极为重要。
The super tau-charm facility is a future project of high luminosity electron-positron collider, which will achieve the luminosity of 100 times of the current running facility BEPCⅡ in Beijing. In this work, we present a sensitivity study on the Collins asymmetry measurement of e+e-→ππX and KKX using 2.5 fb-1 e+e-→qq Monte Carlo simulation sample generated at the center-of-mass energy of 7 GeV. Extrapolating to the integrated luminosity of 1 ab-1, the statistical sensitivities of the Collins asymmetries of charged ππ pairs are at the level of 10-4, while for the charged KK pairs, the sensitivities are in the range of 10-3. Research shows that the accuracy of the asymmetry measurement is affected to a large extent by the background level (mostly from weak processes) and K-π misidentification. So an improved particle discrimination power using Cherenkov detector is very important for this project.
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