(10) trinos can thus escape from regions of space where light
and other kinds of electromagnetic radiation are blocked
by matter. Furthermore, neutrinos carry with them
information about the site and circumstances of their
production: therefore, the detection of cosmic neutrinos
(15) could provide new information about a wide variety of
cosmic phenomena and about the history of the uni-
verse.
But how can scientists detect a particle that interacts
so infrequently with other matter? Twenty-five years
(20) passed between Pauli’s hypothesis that the neutrino
existed and its actual detection: since then virtually all
research with neutrinos has been with neutrinos created
artificially in large particle accelerators and studied
under neutrino microscopes. But a neutrino telescope,
(25) capable of detecting cosmic neutrinos, is difficult to co-
nstruct. No apparatus can detect neutrinos unless it is
extremely massive, because great mass is synonymous
with huge numbers of nucleons (neutrons and protons),
and the more massive the detector, the greater the pro-
(30) bability of one of its nucleon’s reacting with a neutrino.
In addition, the apparatus must be sufficiently shielded
from the interfering effects of other particles.
Fortunately, a group of astrophysicists has proposed
a means of detecting cosmic neutrinos by harnessing the
(35) mass of the ocean. Named DUMAND, for Deep Under-
water Muon and Neutrino Detector, the project calls for
placing an array of light sensors at a depth of five kilo-
meters under the ocean surface. The detecting medium is