Lake Baikal neutrino telescope detects neutrinos

Another Markov-style neutrino detector was built in Lake Baikal, Russia. The largest and deepest freshwater lake in the world, Lake Baikal had extremely clear and unpolluted water whose surface froze in the winter, making it an ideal environment in which to deploy a neutrino telescope.

Just after its four strings of sensors were installed, in April and May 1996, the Baikal telescope detected the first-ever “upgoing” neutrino candidates in an underwater detector—two of them! They had come through Earth and up through the detector. However, they were created by cosmic ray interactions in Earth’s atmosphere, not in extreme astrophysical environments or events.

Schematic of the Lake Baikal neutrino telescope.
Schematic of the Lake Baikal neutrino telescope. Credit: I. A. Belolaptikov et al.