0000000000024689
AUTHOR
Sabya Sachi Chatterjee
Non-Unitarity of the lepton mixing matrix at the European spallation source
If neutrinos get mass through the exchange of lepton mediators, as in seesaw schemes, the neutrino appearance probabilities in oscillation experiments are modified due to effective nonunitarity of the lepton mixing matrix. This also leads to new CP phases and an ambiguity in underpinning the ''conventional'' phase of the three-neutrino paradigm. We study the CP sensitivities of various setups based at the European spallation source neutrino super-beam (ESSnuSB) experiment in the presence of nonunitarity. We also examine its potential in constraining the associated new physics parameters. Moreover, we show how the combination of DUNE and ESSnuSB can help further improve the sensitivities on …
Resolving the atmospheric octant by an improved measurement of the reactor angle
Taking into account the current global information on neutrino oscillation parameters we forecast the capabilities of future long baseline experiments such as DUNE and T2HK in settling the atmospheric octant puzzle. We find that a good measurement of the reactor angle $\theta_{13}$ plays a key role in fixing the octant of the atmospheric angle $\theta_{23}$ with such future accelerator neutrino studies.
Cornering the revamped BMV model with neutrino oscillation data
Using the latest global determination of neutrino oscillation parameters from~\cite{deSalas:2017kay} we examine the status of the simplest revamped version of the BMV (Babu-Ma-Valle) model, proposed in~\cite{Morisi:2013qna}. The model predicts a striking correlation between the "poorly determined" atmospheric angle $\theta_{23}$ and CP phase $\delta_{CP}$, leading to either maximal CP violation or none, depending on the preferred $\theta_{23}$ octants. We determine the allowed BMV parameter regions and compare with the general three-neutrino oscillation scenario. We show that in the BMV model the higher octant is possible only at $99\%$ C.L., a stronger rejection than found in the general c…
Probing atmospheric mixing and leptonic CP violation in current and future long baseline oscillation experiments
We perform realistic simulations of the current and future long baseline experiments such as T2K, NO$\nu$A, DUNE and T2HK in order to determine their ultimate potential in probing neutrino oscillation parameters. We quantify the potential of these experiments to underpin the octant of the atmospheric angle $\theta_{23}$ as well as the value and sign of the CP phase $\delta_{CP}$.