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.
WANG Binlong
,
Lü Xiaorui
,
ZHENG Yangheng
. Collins effect at super tau-charm facility[J]. Journal of University of Chinese Academy of Sciences, 2021
, 38(4)
: 433
-441
.
DOI: 10.7523/j.issn.2095-6134.2021.04.001
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