Joint short- and long-baseline constraints on light sterile neutrinos

Understand

Recent studies have evidenced that long-baseline (LBL) experiments are sensitive to the extra CP-phases involved with light sterile neutrinos, whose existence is suggested by several anomalous short-baseline (SBL) results.

• We show that, within the 3+1 scheme, the combination of the existing SBL data with the LBL results coming from the two currently running experiments NO$\nu$A and T2K, enables us to simultaneously constrain two active-sterile mixing angles $\theta_{14}$ and $\theta_{24}$ and two CP-phases $\delta_{13} \equiv \delta$ and $\delta_{14}$, albeit the information on the second CP-phase is still weak at the moment.
• The two mixing angles are basically determined by the SBL data, while the two CP-phases are constrained by the LBL experiments, once the information coming from the SBL setups is taken into account.
• We also assess the robustness/fragility of the estimates of the standard 3-flavor parameters in the more general 3+1 scheme.