The silver channel at the Neutrino Factory

Abstract

We notice that looking for $\hat{I}{½}_e\to \hat{I}{½}_{\ddot{I}}„$ at the same time as $\hat{I}{½}_e\to \hat{I}{½}_{\hat{I}}¼$ oscillations could significantly help to reduce the errors in the leptonic CP-violating phase $\hat{I}´$ measurement. We show how the $\hat{I}{½}_e\to \hat{I}{½}_{\hat{I}}¼$ (``golden'') and $\hat{I}{½}_e\to \hat{I}{½}_{\ddot{I}}„$ (``silver'') transitions observed at an OPERA-like 2 Kton lead-emulsion detector at L = 732 Km, in combination with the $\hat{I}{½}_e\to \hat{I}{½}_{\hat{I}}¼$ transitions observed at a 40 Kton magnetized iron detector with a baseline of L = 3000 Km, strongly reduce the so-called $(\hat{I}{¸}_{13},\hat{I}´)$ ambiguity. We also show how a moderate increase in the OPERA-like detector mass (4 Kton instead of 2 Kton) completely eliminates the clone regions even for small values of $\hat{I}{¸}_{13}$.

Latex2e, 36 pages, using epsfig