The large-angle photon veto system for the NA62 experiment at the CERN SPS
Abstract
The branching ratio (BR) for the decay K^+ \to \pi^+\nu\bar{\nu} is a sensitive probe for new physics. The NA62 experiment at the CERN SPS will measure this BR to within about 10%. To reject the background from dominant kaon decays with final state photons, the large-angle photon vetoes (LAVs) must detect photons of energy as low as 200 MeV with an inefficiency of less than 10^{-4}. The LAV detectors make use of lead glass blocks recycled from the OPAL electromagnetic calorimeter barrel. We describe the mechanical design and challenges faced during construction, the characterization of the lead glass blocks and solutions adopted for monitoring their performance, and the development of front-end electronics to allow simultaneous time and energy measurements over an extended dynamic range using the time over-threshold technique. Our results are based on test-beam data and are reproduced by a detailed Monte Carlo simulation that includes the readout chain.
Keywords
Cite
@article{arxiv.1207.6021,
title = {The large-angle photon veto system for the NA62 experiment at the CERN SPS},
author = {F. Ambrosino and B. Angelucci and A. Antonelli and F. Costantini and G. D'Agostini and D. Di Filippo and R. Fantechi and S. Gallorini and S. Giudici and E. Leonardi and I. Mannelli and P. Massarotti and M. Moulson and M. Napolitano and V. Palladino and F. Rafaelli and M. Raggi and G. Saracino and M. Serra and T. Spadaro and P. Valente and S. Venditti},
journal= {arXiv preprint arXiv:1207.6021},
year = {2015}
}
Comments
LaTeX, 7 pages, 11 attached .eps files. Prepared for the Proceedings of the XVth International Conference on Calorimetry in High Energy Physics (Calor 2012), Santa Fe, NM, 4-8 June 2012