Shape functions from B{yields}X{sub c}l{nu}{sub l}
Abstract
We study inclusive semileptonic B{yields}X{sub c}l{nu}{sub l} decay using the power counting m{sub c}{approx}{radical}({lambda}{sub QCD}m{sub b}). Assuming this scaling for the charmquark mass, the decay kinematics can be chosen to access the shapefunction region even in b{yields}c transitions. To apply effective field theory methods in this region we extend softcollinear effective theory to describe massive collinear quarks. We calculate the treelevel decay rate, including O({lambda}{sub QCD}/m{sub b}) power corrections, and show that it factorizes into a convolution of jet and shape functions. We identify a certain kinematical variable whose decay spectrum is proportional to the universal leadingorder shape function familiar from b{yields}u decay, and speculate as to whether information about this shape function can be extracted from data on b{yields}c decay.
 Authors:
 Theoretische Physik 1, Fachbereich Physik, Universitaet Siegen, D57068 Siegen (Germany)
 Publication Date:
 OSTI Identifier:
 20776695
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.73.036003; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; B MESONS; C QUARKS; CORRECTIONS; JET MODEL; NEUTRINOS; QUANTUM CHROMODYNAMICS; REST MASS; S QUARKS; SEMILEPTONIC DECAY
Citation Formats
Boos, H., Feldmann, T., Mannel, T., and Pecjak, B.D.. Shape functions from B{yields}X{sub c}l{nu}{sub l}. United States: N. p., 2006.
Web. doi:10.1103/PhysRevD.73.036003.
Boos, H., Feldmann, T., Mannel, T., & Pecjak, B.D.. Shape functions from B{yields}X{sub c}l{nu}{sub l}. United States. doi:10.1103/PhysRevD.73.036003.
Boos, H., Feldmann, T., Mannel, T., and Pecjak, B.D.. Wed .
"Shape functions from B{yields}X{sub c}l{nu}{sub l}". United States.
doi:10.1103/PhysRevD.73.036003.
@article{osti_20776695,
title = {Shape functions from B{yields}X{sub c}l{nu}{sub l}},
author = {Boos, H. and Feldmann, T. and Mannel, T. and Pecjak, B.D.},
abstractNote = {We study inclusive semileptonic B{yields}X{sub c}l{nu}{sub l} decay using the power counting m{sub c}{approx}{radical}({lambda}{sub QCD}m{sub b}). Assuming this scaling for the charmquark mass, the decay kinematics can be chosen to access the shapefunction region even in b{yields}c transitions. To apply effective field theory methods in this region we extend softcollinear effective theory to describe massive collinear quarks. We calculate the treelevel decay rate, including O({lambda}{sub QCD}/m{sub b}) power corrections, and show that it factorizes into a convolution of jet and shape functions. We identify a certain kinematical variable whose decay spectrum is proportional to the universal leadingorder shape function familiar from b{yields}u decay, and speculate as to whether information about this shape function can be extracted from data on b{yields}c decay.},
doi = {10.1103/PhysRevD.73.036003},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 73,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2006},
month = {Wed Feb 01 00:00:00 EST 2006}
}

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