Collins effect at super tau-charm facility

doi:10.7523/j.issn.2095-6134.2021.04.001

Abstract

Abstract: 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.

Key words: electron-positron collider, super tau-charm facility, quark fragmentation function, Collins asymmetry

CLC Number:

Q572.214

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.

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