Possible duality violations in tau decay and their impact on the determination of alpha_s

Cata, Oscar; Golterman, Maarten; Peris, Santiago

Possible duality violations in tau decay and their impact on the determination of alpha_s

Authors

Cata, Oscar

Golterman, Maarten

Peris, Santiago

Description

We discuss the issue of duality violations in hadronic tau decay. After introducing a physically motivated ansatz for duality violations, we estimate their possible size by fitting this ansatz to the tau experimental data provided by the ALEPH collaboration. Our conclusion is that these data do not exclude significant duality violations in tau decay. This may imply an additional systematic error in the value of alpha_s(m_tau), extracted from tau decay, as large as δalpha_s(m_tau) \sim 0.003-0.010 .
20 pages, 4 figures. Minor fixes in the Appendix