Search for modulations of the solar Be-7 flux in the next-generation neutrino observatory LENA

A next-generation liquid-scintillator detector will be able to perform high-statistics measurements of the solar neutrino flux. In LENA, solar Be-7 neutrinos are expected to cause 1.7x10^4 electron recoil events per day in a fiducial volume of 35 kilotons. Based on this signal, a search for periodic modulations on sub-percent level can be conducted, surpassing the sensitivity of current detectors by at least a factor of 20. The range of accessible periods reaches from several minutes, corresponding to modulations induced by helioseismic g-modes, to tens of years, allowing to study long-term changes in solar fusion rates.Comment: 15 pages, 9 figure

Rekonstruktion und Messung kosmogener Signale im Neutrino-Experiment Borexino

Muons, as well as the neutrons and radioisotopes they produce in nuclear spallation processes, constitute a significant background in the neutrino experiment Borexino, which is located at the Laboratori Nazionali del Gran Sasso underground site at a depth of 3800 meters of water equivalent. The work encompasses the identification, spatial reconstruction, and measurement of rates and production yields of these cosmogenic events.Myonen, sowie die Neutronen und Radioisotope die sie in Kernspallationen erzeugen, verursachen einen signifikanten Untergrund im Neutrino-Experiment Borexino. Dieses befindet sich im Laboratori Nazionali del Gran Sasso Untergrundlabor in einer Tiefe von 3800 Meter Wasseräquivalent. Die Arbeit umfasst die Identifikation, räumliche Rekonstruktion und Bestimmung der Produktionsraten dieser kosmogenen Ereignisse

Production and suppression of [sup 11]C in the solar neutrino experiment Borexino

Cosmogenic C-11 is produced in-situ by atmospheric mons and forms the main background for the measurement of solar pep- and CNO-neutrinos. However, FLUKA simulations show that the majority of C-11 is accompanied by a free neutron in the final state, thus allowing for an efficient tagging method, the so-called Three-Fold Coincidence technique. The technique and its first applications on Borexino data are presented

The next-generation liquid-scintillator neutrino observatory LENA

We propose the liquid-scintillator detector LENA (Low Energy Neutrino Astronomy) as a next-generation neutrino observatory on the scale of 50 kt. The outstanding successes of the Borexino and KamLAND experiments demonstrate the large potential of liquid-scintillator detectors in low-energy neutrino physics. LENA's physics objectives comprise the observation of astrophysical and terrestrial neutrino sources as well as the investigation of neutrino oscillations. In the GeV energy range, the search for proton decay and long-baseline neutrino oscillation experiments complement the low-energy program. Based on the considerable expertise present in European and international research groups, the technical design is sufficiently mature to allow for an early start of detector realization.Comment: Whitepaper for the LENA low-energy neutrino detector, 67 pages, 32 figure