Soudan 1 was a particle detector located in the
Soudan Mine in Northern Minnesota, United States, which operated for a year in 1981–82. It was a 30-ton tracking calorimeter whose primary purpose was to search for
proton decay
In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron. The proton decay hypothesis was first formulated by Andrei Sakharov ...
. It set a lower limit on the lifetime of the proton of 1.6×10
30 years as well as upper limits on the density of
magnetic monopoles
In particle physics, a magnetic monopole is a hypothetical elementary particle that is an isolated magnet with only one magnetic pole (a north pole without a south pole or vice versa). A magnetic monopole would have a net north or south "magneti ...
. It also served as a prototype for the following
Soudan 2
Soudan 2 was a particle detector located in the Soudan Mine in Northern Minnesota, United States, that operated from 1989 to 2001. It was a 960-ton iron tracking calorimeter whose primary purpose was to search for proton decay, although its data ...
and
MINOS experiments.
Design and operation
Soudan 1 was installed 590 meters below the surface and brought into routine operation in August 1981 by high-energy physics research groups from the
University of Minnesota
The University of Minnesota, formally the University of Minnesota, Twin Cities, (UMN Twin Cities, the U of M, or Minnesota) is a public land-grant research university in the Twin Cities of Minneapolis and Saint Paul, Minnesota, United States. ...
and
Argonne National Laboratory. The detector was a 3×3×2m
3 block of
iron oxide-loaded concrete instrumented with 3456
gas proportional tubes. It was surrounded on five sides by a veto shield of solid
scintillator, which was completed in October 1981. This allowed events which might otherwise have looked like proton decay, but were actually caused by
cosmic rays
Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our ow ...
, to be discarded. It had a total running time of 0.97 years.
See also
*
Particle physics
Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) an ...
*
Proton decay
In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron. The proton decay hypothesis was first formulated by Andrei Sakharov ...
References
{{Proton decay experiments
Particle experiments