Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis

Details Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis

2011-10-10

arxiv.org/abs/1110.2026v2

Physics

High Energy Physics

High Energy Physics - Phenomenology

Results now given for both FOPT and CIPT. A few additional comments have been added

Scientific paper

Experimental data on the total cross section of $e^+ e^-$ annihilation into hadrons are confronted with QCD and the operator product expansion using finite energy sum rules. Specifically, the power corrections in the operator product expansion, i.e. the vacuum condensates, of dimension $d = 2$, 4 and 6 are determined using recent isospin $I=0+1$ data sets. Reasonably stable results are obtained which are compatible within errors with values from $\tau$-decay. However, the rather large data uncertainties, together with the current value of the strong coupling constant, lead to very large errors in the condensates. It also appears that the separation into isovector and isoscalar pieces introduces additional uncertainties and errors. In contrast, the high precision $\tau$-decay data of the ALEPH collaboration in the vector channel allows for a more precise determination of the condensates. This is in spite of QCD asymptotics not quite been reached at the end of the $\tau$ spectrum. We point out that isospin violation is negligible in the integrated cross sections, unlike the case of individual channels.

Affiliated with

Also associated with

No associations

Rating

Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis 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 Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Confronting electron-positron annihilation into hadrons with QCD: an operator product expansion analysis will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-147153