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تسجيل مستخدم جديدInvariant-mass and fractional-energy dependence of inclusive production of di-hadrons in $e^+e^-$ annihilation at $sqrt{s}=$ 10.58 GeV
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The inclusive cross sections for di-hadrons of charged pions and kaons ($e^+e^- rightarrow hhX$) in electron-positron annihilation are reported. They are obtained as a function of the total fractional energy and invariant mass for any di-hadron combination in the same hemisphere as defined by the thrust event-shape variable and its axis. Since same-hemisphere di-hadrons can be assumed to originate predominantly from the same initial parton, di-hadron fragmentation functions are probed. These di-hadron fragmentation functions are needed as an unpolarized baseline in order to quantitatively understand related spin-dependent measurements in other processes and to apply them to the extraction of quark transversity distribution functions in the nucleon. The di-hadron cross sections are obtained from a $655,{rm fb}^{-1}$ data sample collected at or near the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider.
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