The OPERA detector at the Gran Sasso underground laboratory (LNGS) was used to measure the cosmic ray muon charge ratio Rμ = Nμ+/Nμ− in the TeV energy region. We analyzed 403069 cosmic ray muons corresponding to 113.4 days of livetime during the 2008 CNGS run. We computed separately the muon charge ratio for single and for multiple muon events in order to select different energy regions of the primary cosmic ray spectrum and to test the Rμ dependence on the primary composition. Rμ is also shown as a function of the “vertical surface energy” Eμ cos !. A fit to a simplified model of muon production in atmosphere allowed the determination of the pion and kaon charge ratios weighted by the cosmic ray energy spectrum.
Measurements of the cosmic ray muon charge ratio with the OPERA detector / N. Mauri; M. Sioli. - STAMPA. - 1:(2010), pp. 259-261. (Intervento presentato al convegno Workshop European Strategy for Future Neutrino Physics tenutosi a CERN, Geneva, Switzerland nel 1-3 Oct 2009).
Measurements of the cosmic ray muon charge ratio with the OPERA detector
MAURI, NICOLETTA;SIOLI, MAXIMILIANO
2010
Abstract
The OPERA detector at the Gran Sasso underground laboratory (LNGS) was used to measure the cosmic ray muon charge ratio Rμ = Nμ+/Nμ− in the TeV energy region. We analyzed 403069 cosmic ray muons corresponding to 113.4 days of livetime during the 2008 CNGS run. We computed separately the muon charge ratio for single and for multiple muon events in order to select different energy regions of the primary cosmic ray spectrum and to test the Rμ dependence on the primary composition. Rμ is also shown as a function of the “vertical surface energy” Eμ cos !. A fit to a simplified model of muon production in atmosphere allowed the determination of the pion and kaon charge ratios weighted by the cosmic ray energy spectrum.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
