Development of a Liquid Scintillator and of Data ... - Borexino - Infn

1 Solar Neutrinos
1.2.3 Future Experiments
Borexino and KamLAND
BOREXINO and KamLAND [Bra00, Pie01] both aim to detect solar Be neutrinos by neutrinoelectron
scattering using liquid scintillation spectroscopy. The physics goals and the design of
BOREXINO will be described in more detail in chap. 2. The design of KamLAND is very similar
to that of BOREXINO, but with three times larger scintillator mass (1000 t). The KamLAND
detector is currently under construction in the old Kamioka site (Japan); data taking will start
in 2001. The first stage of KamLAND is primarily devoted to detecting reactor antineutrino
oscillations. At a later time, low-energy solar neutrino detection is also envisioned, but this will
require an additional improvement of radiopurity beyond the present design specifications.
LENS
The LENS project (l ¯ ow ēnergy n ¯ eutrino s ¯ pectrometer) aims for real-time spectroscopy of solar
electron neutrinos in the sub-MeV energy range [Rag97, Cri00]. It will use scintillator loaded
with Yb, Gd or In for the detection of the inverse beta decay
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Characteristic electron-gamma coincidence signatures due to isomeric states occupied in the
daughter nuclei (with lifetimes of ns) could help to achieve the required background
reduction at very low energies. Combining the measured CC-rate of Be neutrinos in LENS
with the rate measured in BOREXINO (CC + NC) could give an unambiguous proof of neutrino
oscillations.
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