The Scientific Method

Sub Atomic non-Atomic Particles

The world of particle physics is filled with studies utilizing giant equipment to hurl atoms at each other, scientists with big egos (this stuff is filled with Einsteinian theory), and at least a few people with a sense of humor (one adjective used to describe an aspect of certain sub-atomic particles is "flavor"). Muons are one of the many particles physicists know about which are smaller than the smalles atom. The particles most commonly known are protons, neutrons, and electrons. If you ever have any doubts about their charges, just remember that neu-trons are neu-tral, and this clean joke: An atom walks into a bar and says to the bartender, "Hey Joe, I think I lost an electron." The bartender says, "Are you sure?" The atom replies, "I'm positive." i.e. electrons are negative and protons are postive. Electrons are the smalles of the three, but there are other particles which may be smaller.

Muons are smaller than protons or neutrons and are larger than electrons, even though they have the same charge. They are not usually found in atoms, but are rather a particle in a state of decay between other sub-atomic particles. When a muon is in the atom, the atom is much smaller than a normal atom, because its large mass pulls the atomic particles closer together, or they reside in a lower energy state. Muons, with their negative charge also have a counterpart with a positive charge, the antimuon.

Muons enter the Earth's atmosphere and come crashing to the ground at tremendous speed. Cosmic rays, not just a facet of science fiction, produce these and other sub-atomic particles. Muons decay from large pions, created in the upper atmosphere by these rays.

Because these particles are in a constant state of decay, i.e. are losing energy to their environment, any machine that detects them, will detect them at different rates depending on where in the atmosphere the machine is located. This is simply demonstrated by the two muon counters in Switerland. One, at Jungfraujoch, high in the Swiss Alps (often called "The Top of Europe), and another, down in Bern, are counting muons as you read this. Because of its much higher altitude, the Jungfraujoch counter intercepts more atmospheric muons than the Bern counter, by the time the muons have gotten down to Bern, more have decayed, and are no longer muons. This simple demonstration, complete with online counter and webcams is available at http://lheppc17.unibe.ch/~einstein/Einstein03.php. It's Einstein theory simplified.

posted by Thomas @ 1:56 PM