https://doi.org/10.1140/epjp/s13360-019-00083-2
Regular Article
The effect of the earth matter on three neutrino oscillations and sensitivity to CP phase parameter
Centre for High Energy Physics, Punjab University, Lahore, 54590, Pakistan
* e-mail: bshafaq.chep@pu.edu.pk
Received:
28
August
2019
Accepted:
27
December
2019
Published online:
23
January
2020
We find an analytical expression of neutrino evolution operator in the Earth matter using perturbative approach in the context of three neutrino oscillations. We find our analytical expression highly accurate, by comparing its results with the numerical solutions of neutrino evolution equation at energy scales relevant for solar, reactor, atmospheric, and accelerator neutrinos. By applying two different models of Earth density, we find that 2-neutrino approximation provide systematic errors similar or larger to the one given by the uncertainty in the Earth Model. We also study how the Earth matter effect can change the sensitivity to CP phase parameter 
. Through nadir angle averaged conversion probabilities of neutrino and anti-neutrino, we find that the sensitivity to is maximum in the energy range 0.2–1 GeV and through energy averaged conversion probabilities, we find that the sensitivity is maximum about nadir angle 
for neutrinos oscillating in the Earth matter.
© Società Italiana di Fisica (SIF) and Springer-Verlag GmbH Germany, part of Springer Nature, 2020
