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Error Estimation of Fragmentation Functions Based on Global QCD Analysis. - 摂動論的 QCD に基づいた破砕関数の誤差評価 -. Tokyo Inst. of Tech. Y. Imazu, Y. Miyachi, T. Hasegawa, Xiaorui Lu , T.-A. Shibata. 20th Sep., 2006. Contents. 1. Motivation 2. Analysis Method 3. Results 4. Summary.
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Error Estimation of Fragmentation Functions Based on Global QCD Analysis - 摂動論的QCDに基づいた破砕関数の誤差評価 - Tokyo Inst. of Tech. Y. Imazu, Y. Miyachi, T. Hasegawa,Xiaorui Lu, T.-A. Shibata 20th Sep., 2006 Contents 1. Motivation 2. Analysis Method 3. Results 4. Summary
Fragmentation Function : : Phys. Rev., D62:054001 “ ” 1. Motivation HERMES SIDIS Data with Fitted Curve at ←Determined by pQCD analysis with hadron productions in e+ e-collision How much does the error of FFs have an effect to A 1h ??
In the calculation of cross section 2. Analysis Method Parameterization of FFs at Initial Scale Totally 11 parameters for π、K each
Experimental data used in my fitting PION GeV SLAC-PEP-TPC ( 0.1 < z < 0.8 ) 11 0 0 29.0 SLAC-SLC-SLD ( 0.05 < z < 0.8 ) 27 16 16 91.2 Totally 70 KAON GeV SLAC-PEP-TPC ( 0.1 < z < 0.8 ) 10 0 0 29.0 SLAC-SLC-SLD ( 0.05 < z < 0.8 ) 25 14 14 91.2 Totally 63 s
PIONFF results : parameters and plots LO NLO up → π + charm → π + gluon → π +
KAONFF results : parameters and plots LO NLO charm → K + up → K +
h=pion h=kaon The effect of FF ambiguity to A1h (LO) Lagrange Multiplier Method :
4. Summary ・Fragmentation functions (FFs) are needed for pQCD calculation of SIDIS process. However, the errors of FFs had not been estimated. ・ By performing pQCD (LO, NLO) fit to e+ e- experimental results, We obtained the FF results, which are consistent with those of Kretzer. ・ We estimated the errors contained in the FFs. ・ The effect of FF ambiguity to SIDIS A1h calculation (LO) was evaluated with chi-square value of FF fit (Lagrange Multiplier Method) to e+ e- data. The effect turned out to be less than 1%. ・Outlook ; chi-square of SIDIS data