TY - JOUR
T1 - Padé theory applied to the vacuum polarization of a heavy quark
AU - Masjuan, P.
AU - Peris, S.
PY - 2010/3/29
Y1 - 2010/3/29
N2 - The vacuum polarization of a quark, when considered in terms of the external momentum q2, is a function of the Stieltjes type. Consequently, the mathematical theory of Padé approximants assures that the full function, at any finite value of q2 away from the physical cut, can be reconstructed from its low-energy power expansion around q2 = 0. We illustrate this point by applying this theory to the vacuum polarization of a heavy quark and obtain the value of the constant K(2) governing the threshold expansion at order O (αs2). © 2010 Elsevier B.V. All rights reserved.
AB - The vacuum polarization of a quark, when considered in terms of the external momentum q2, is a function of the Stieltjes type. Consequently, the mathematical theory of Padé approximants assures that the full function, at any finite value of q2 away from the physical cut, can be reconstructed from its low-energy power expansion around q2 = 0. We illustrate this point by applying this theory to the vacuum polarization of a heavy quark and obtain the value of the constant K(2) governing the threshold expansion at order O (αs2). © 2010 Elsevier B.V. All rights reserved.
KW - Heavy quark physics
KW - Padé approximants
U2 - 10.1016/j.physletb.2010.02.069
DO - 10.1016/j.physletb.2010.02.069
M3 - Article
SN - 0370-2693
VL - 686
SP - 307
EP - 312
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
IS - 4-5
ER -