Probing new physics with coherent neutrino scattering off nuclei

Abstract

The possibility off measuring for the first time neutrino-nuclei coherent scattering has been recently discussed by several experimental collaborations. It is shown that such a measurement may be very sensitive to non-standard interactions of neutrinos with quarks and might set better constraints than those coming from future neutrino factory experiments. We also comment on other types of new physics tests, such as extra heavy neutral gauge bosons, where the sensitivity to some models is slightly better than the Tevatron constraint and, therefore, could give complementary bounds.

Sensitivity toZ-prime and nonstandard neutrino interactions from ultralow threshold neutrino-nucleus coherent scattering

“…Since various Z models couple distinctly to up and down quarks, differential and rational event counts in detectors with contrasting atomic and mass numbers, such as 72 Ge and 28 Si, can be very sensitive to deviations from the standard model in a manner that cancels leading systematic uncertainties. This sensitivity to the existence and mode of new Z or µ ν physics, even more so than the scale, is a key distinguishing benefit nuclear recoil detectors over other approaches [32], as will be further elaborated in the final section.…”

“…In order to compute the cumulative expected Standard Model anti-neutrino capture (cf. Ref [32]), it is necessary to integrate in the region of the E ν vs. T R plane that is above E ν > E min ν = (T R + 2M T R + T 2 R )/2, which is the minimal neutrino energy (i.e. the inversion of the expression for T max R ) required to trigger a given recoil, and SM Coherent Nuclear Scattering…”

“…Percentage In addition to the structured Z contributions to the nuclear recoil rate, it is also possible to probe for generic non-standard neutrino interaction vertices [32,50], both of the flavor-diagonal, and flavor-mixed varieties. We adopt the notation and normalization of Ref.…”

Probing nonstandard interactions with reactor neutrinos

“…We have demonstrated that neutrino coherent scattering off nuclei has a lot of potential to make precision tests of new physics, in particular, to probe NSI [1,2] that naturally appear in many extensions of the Standard Model. A new experiment would be able to test large NSI parameters and therefore may exclude new solutions to the solar neutrino data [12].…”

“…It was shown recently that coherent neutrino nuclei scattering is a very sensitive probe to NSI [1,2]. The sensitivity to some specific NSI models, such as extra heavy neutral gauge bosons, leptoquarks, supersymmetry with broken R-parity, could be better than present constraints and, * Speaker: T.I.…”