We report an improved geo-neutrino measurement with Borexino from 2056 days of data taking. The present exposure is (5.5±0.3)×1031 proton×yr. Assuming a chondritic Th/U mass ratio of 3.9, we obtain 23.7+6.5−5.7(stat)+0.9−0.6(sys) geo-neutrino events. The null observation of geo-neutrinos with Borexino alone has a probability of 3.6×10−9 (5.9σ). A geo-neutrino signal from the mantle is obtained at 98\% C.L. The radiogenic heat production for U and Th from the present best-fit result is restricted to the range 23-36 TW, taking into account the uncertainty on the distribution of heat producing elements inside the Earth.
Spectroscopy of geoneutrinos from 2056 days of Borexino data / Agostini, M.; Suvorov, Yury; Et, Al.. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - 92:3(2015). [10.1103/PhysRevD.92.031101]
Spectroscopy of geoneutrinos from 2056 days of Borexino data
SUVOROV, YURY;
2015
Abstract
We report an improved geo-neutrino measurement with Borexino from 2056 days of data taking. The present exposure is (5.5±0.3)×1031 proton×yr. Assuming a chondritic Th/U mass ratio of 3.9, we obtain 23.7+6.5−5.7(stat)+0.9−0.6(sys) geo-neutrino events. The null observation of geo-neutrinos with Borexino alone has a probability of 3.6×10−9 (5.9σ). A geo-neutrino signal from the mantle is obtained at 98\% C.L. The radiogenic heat production for U and Th from the present best-fit result is restricted to the range 23-36 TW, taking into account the uncertainty on the distribution of heat producing elements inside the Earth.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
