New limits for the Violation of Equivalence Principle (VEP) are obtained considering the mass-flavor mixing hypothesis. This analysis includes observations of solar and reactor neutrinos and has obtained a limit for the VEP parameter $|Delta gamma|$ contributing to the $ u_e$ and $bar{ u}_e$ disappearance channels of the order $|Delta gamma|<10^{-14}$, when it is assumed that neutrinos are mainly affected by the gravitational potential $varphiapprox 10^{-5}$ due to the Great Attractor.
The oscillation of neutrino flavors, due to its interferometry nature, is extremely sensitive to the phase differences developing during the propagation of neutrinos. In this paper we investigate the effect of the Violation of Equivalence Principle (VEP) on the flavor oscillation probabilities of atmospheric and cosmic neutrinos observed at neutrino telescopes such as IceCube. Assuming a general parameterization of VEP, dubbed extended parameter space, we show that the synergy between the collected data of high energy atmospheric and cosmic neutrinos severely constrains the VEP parameters. Also, the projected sensitivity of IceCube-Gen2 to VEP parameters is discussed.
The recent high-statistics high-energy atmospheric neutrino data collected by IceCube open a new window to probe new physics scenarios that are suppressed in lower energy neutrino experiments. In this paper we analyze the IceCube atmospheric neutrino data to constrain the Violation of Equivalence Principle (VEP) in the framework of three neutrinos with non-universal gravitational couplings. In this scenario the effect of VEP on neutrino oscillation probabilities can be parametrized by two parameters $Delta gamma_{21}equiv gamma_2-gamma_1$ and $Deltagamma_{31}equiv gamma_3-gamma_1$, where $gamma_i$s denote the coupling of neutrino mass eigenstates to gravitational field. By analyzing the latest muon-tracks data sets of IceCube-40 and IceCube-79, besides providing the 2D allowed regions in $(phiDeltagamma_{21},phiDeltagamma_{31})$ plane, we obtain the upper limits $|phiDeltagamma_{21}| < 9.1times 10^{-27}$ (at 90% C.L.) which improves the previous limit by $sim4$ orders of magnitude and $|phiDeltagamma_{31}| lesssim 6times 10^{-27}$ (at 90% C.L.) which improves the current limit by $sim1$ order of magnitude. Also we discuss in detail and analytically the effect of VEP on neutrino oscillation probabilities.
I review the calculation of the next-to-leading order behavior of high-energy amplitudes in N=4 SYM and QCD using the operator expansion in Wilson lines.
An analytic coordinate-space expression for the next-to-leading order photon impact factor for small-$x$ deep inelastic scattering is calculated using the operator expansion in Wilson lines.
We report a calculation of the perturbative matching coefficients for the transverse-momentum-dependent parton distribution functions for quark at the next-to-next-to-next-to-leading order in QCD, which involves calculation of non-standard Feynman integrals with rapidity divergence. We introduce a set of generalized Integration-By-Parts equations, which allows an algorithmic evaluation of such integrals using the machinery of modern Feynman integral calculation.
G. A. Valdiviesso
,M. M. Guzzo
,P. C. Holanda
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(2013)
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"Probing New Limits for the Violation of the Equivalence Principle in the solar-reactor neutrino sector as a next to leading order effect"
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Gustavo Valdiviesso
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