Combined directional and spectral analysis of solar neutrinos from Carbon-Nitrogen-Oxygen fusion cycle with Borexino Experiment

Borexino, placed at LNGS in Italy, was a 280-ton liquid scintillator detector that took data from May 2007 to October 2021. Thanks to its unprecedented radio-purity, the real time spectroscopic measurement of solar neutrinos from both the pp-chain and Carbon-Nitrogen-Oxygen (CNO) fusion cycle of the Sun has been performed. Borexino also reported the first directional measurement of sub-MeV7Be solar neutrinos with the Phase-I period (May 2007-May 2010) using a novel technique called Correlated and Integrated Directionality (CID), exploiting the sub-dominant and directional Cherenkov photons detected at early times. For the first time, we provide the CNO solar neutrinos measurement without using an independent constraint on210Bi background rate by exploiting the CID technique on the complete Borexino detector live time dataset. This article presents the complete analysis strategy and the latest results on CNO solar neutrinos obtained by using the CID technique in Borexino. In addition, we also present the most precise CNO measurement obtained by Borexino using a spectral fit on the Phase-III dataset as used in 2022 analysis, where the novel CID result is now applied as an additional constraint.