The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections

Details The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections

1997-02-13

arxiv.org/abs/hep-ph/9702331v1

Phys.Rev. D57 (1998) 1615-1632

Physics

High Energy Physics

High Energy Physics - Phenomenology

26 pages, latex, five ps figures included

Scientific paper

10.1103/PhysRevD.57.1615

The QED vacuum polarization function is calculated to O(alpha^2) (next-to-leading order) accuracy in the threshold regime by using the concept of effective field theories to resum diagrams with the instantaneous Coulomb exchange of longitudinally polarized photons. It is shown that the O(alpha^2) contributions are of order alpha^2 in size rather than alpha^2/Pi^2. The vacuum polarization contributions to the O(alpha^6) hyperfine splitting of the positronium ground state are recalculated and differences with an older calculation are pointed out. The results are used to determine O(C_F^2 alpha_s^2) (next-to-next-to-leading order) Darwin corrections to heavy quark-antiquark bound state l=0 wave functions at the origin and to the heavy quark-antiquark production cross section in e^+e^- collisions in the threshold region. The absolute value of the corrections amounts to 10%-20% and 17%-34% in the modulus squared of the ground state wave functions at the origin for the $b\bar b$ and $c\bar c$ systems, respectively. In the case of the $t\bar t$ production cross section in the threshold region the absolute value of the corrections is between 2% and 6% around the 1S peak and between 1% and 2% for higher energies. A critical comment on recent QCD sum rule calculations for the $\Upsilon$ system is made.

Affiliated with

Also associated with

No associations

Rating

The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Vacuum Polarization Function to O(alpha^2) Accuracy Near Threshold and Darwin Corrections will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-100362