Quest for precision in hadronic cross sections at low energy: Monte Carlo tools vs. experimental data

Università di Parma Dipartimento di Fisica 43100 Parma Italy
European Physical Journal C (Impact Factor: 5.08). 12/2009; 66(3). DOI: 10.1140/epjc/s10052-010-1251-4
Source: arXiv


We present the achievements of the last years of the experimental and theoretical groups working on hadronic cross section measurements at the low energy e+e- colliders in Beijing, Frascati, Ithaca, Novosibirsk, Stanford and Tsukuba and on tau decays. We sketch the prospects in these fields for the years to come. We emphasise the status and the precision of the Monte Carlo generators used to analyse the hadronic cross section measurements obtained as well with energy scans as with radiative return, to determine luminosities and tau decays. The radiative corrections fully or approximately implemented in the various codes and the contribution of the vacuum polarisation are discussed. Comment: Report of the "Working Group on Radiative Corrections and Monte Carlo Generators for Low Energies"; 99 pages, submitted to EPJC

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Available from: Andrej B. Arbuzov
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    • "Let us stress that Helac-Phegas has been already extensively used and tested, see e.g. [19] [20] [21] [22] [23] [24]. Moreover, both libraries compute relevant contributions in a very efficient way, using off-shell recursive equations and avoiding a multiple evaluation of recurring building blocks. "
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    • "Our LO results have been generated with the Helac- Dipoles [42] package and cross checked with Helac-Phegas [43] [44], a generator for all parton level processes in the Standard Model, which has, on its own, already been extensively used and tested in phenomenological studies see e.g. [45] [46] [47] [48] [49]. The integration over the fractions x 1 and x 2 of the initial partons is optimized with the help of Parni [50]. "
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