Cosmic radiation dating
The Oh-My-God particle, the highest-energy fermionic cosmic ray detected to date, had an energy of about times more energetic than the highest-energy detected cosmic photons. His father, confronted with the undeniable facts of the theory of relativity, declares his profession outdated and throws the parts of his watch that Hon was working on out the window, urging him to instead pursue a career studying nuclear physics.Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system.They blaze at the speed of light and have been blamed for electronics problems in satellites and other machinery.The resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died.The older a sample is, the less (the period of time after which half of a given sample will have decayed) is about 5,730 years, the oldest dates that can be reliably measured by this process date to around 50,000 years ago, although special preparation methods occasionally permit accurate analysis of older samples.Through this process, some particles acquire tremendously high mass-energies.These are significantly higher than the photon energy of even the highest-energy photons detected to date.
This drawing illustrates air showers from very high energy cosmic rays.Libby received the Nobel Prize in Chemistry for his work in 1960.The radiocarbon dating method is based on the fact that radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen.The idea behind radiocarbon dating is straightforward, but years of work were required to develop the technique to the point where accurate dates could be obtained.Research has been ongoing since the 1960s to determine what the proportion of in the atmosphere has been over the past fifty thousand years.
The effects are shown to be small over the past 500 ka in most circumstances.