Consistent treatment of rapidity divergence in soft-collinear effective theory

被引:0
作者
Junegone Chay
Chul Kim
机构
[1] Korea University,Department of Physics
[2] Seoul National University of Science and Technology,Institute of Convergence Fundamental Studies and School of Liberal Arts
来源
Journal of High Energy Physics | / 2021卷
关键词
Effective Field Theories; Perturbative QCD; Resummation;
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摘要
In soft-collinear effective theory, we analyze the structure of rapidity divergence due to the collinear and soft modes residing in disparate phase spaces. The idea of an effective theory is applied to a system of collinear modes with large rapidity and soft modes with small rapidity. The large-rapidity (collinear) modes are integrated out to obtain the effective theory for the small-rapidity (soft) modes. The full SCET with the collinear and soft modes should be matched onto the soft theory at the rapidity boundary, and the matching procedure becomes exactly the zero-bin subtraction. The large-rapidity region is out of reach for the soft mode, which results in the rapidity divergence. The rapidity divergence in the collinear sector comes from the zero-bin subtraction, which ensures the cancellation of the rapidity divergences from the soft and collinear sectors. In order to treat the rapidity divergence, we construct the rapidity regulators consistently for all the modes. They are generalized by assigning independent rapidity scales for different collinear directions. The soft regulator incorporates the correct directional dependence when the innate collinear directions are not back-to-back, which is discussed in the N-jet operator. As an application, we consider the Sudakov form factor for the back-to-back collinear current and the soft-collinear current, where the soft rapidity regulator for a soft quark is developed. We extend the analysis to the boosted heavy quark sector and exploit the delicacy with the presence of the heavy quark mass. We present the resummed results of large logarithms in the form factors for various currents with the light and the heavy quarks, employing the renormalization group evolution on the renormalization and the rapidity scales.
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共 63 条
[1]  
Chiu J-y(2012)undefined Phys. Rev. Lett. 108 151601-undefined
[2]  
Jain A(2012)undefined JHEP 05 084-undefined
[3]  
Neill D(2007)undefined Phys. Rev. D 76 094015-undefined
[4]  
Rothstein IZ(2012)undefined Phys. Lett. B 713 41-undefined
[5]  
Chiu J-Y(2020)undefined Nucl. Phys. B 960 115193-undefined
[6]  
Jain A(2019)undefined JHEP 04 123-undefined
[7]  
Neill D(2009)undefined Phys. Rev. D 79 053007-undefined
[8]  
Rothstein IZ(2015)undefined Phys. Rev. D 92 074035-undefined
[9]  
Idilbi A(2010)undefined JHEP 11 101-undefined
[10]  
Mehen T(2016)undefined JHEP 03 153-undefined