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MICADAS: ROUTINE AND HIGH-PRECISION RADIOCARBONDATING carbon for relics found at archaeological sites.
 * The prototype of the mini carbon dating machine that is present in Zurich, Germany shows the routine operation of analyzing
 * This machine gives us the capability to detect an accurate reading on how old a relic or a group of remains is.

Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method of determining the age of an object containing organic material by using the properties of radiocarbon (14 C), a radioactive isotope of carbon. The method was invented by Willard Libby in the late 1940s and soon became a standard tool for archaeologists. Libby received the Nobel Prize 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 resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire 14 C by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and from that point onwards the amount of 14 C it contains begins to reduce as the 14 C undergoes radioactive decay. Measuring the amount of 14 C in a sample from a dead plant or animal such as 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 14 C there is to be detected, and because the half-life of 14 C (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 radiocarbon dating are around 50,000 years ago, although special preparation methods occasionally permit dating of older samples.

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 14 C in the atmosphere has been over the past fifty-thousand years. The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age. Other corrections must be made to account for the proportion of 14 C in different types of organisms (fractionation), and the varying levels of 14 C throughout the biosphere (reservoir effects). Additional complications come from the burning of fossil fuels such as coal and oil, and from the above-ground nuclear tests done in the 1950s and 1960s. Fossil fuels contain little detectable 14 C, and as a result there was a noticeable drop in the proportion of 14 C in the atmosphere beginning in the late 19th century. Conversely, nuclear testing increased the amount of 14 C in the atmosphere, to a maximum (reached in 1963) of almost twice what it had been before the testing began.

Measurement of radiocarbon was originally done by beta-counting devices, which counted the amount of beta radiation emitted by decaying 14 C atoms in a sample. Samples were converted to solid carbon for the earliest devices, but it was quickly discovered that converting them to gas or liquid form gave more accurate results. More recently, accelerator mass spectrometry has become the method of choice; it can be used with much smaller samples (as small as individual plant seeds), and gives results much more quickly. Dates are often reported in years "before present", or BP; this actually refers to a baseline of 1950 AD, so that a date of 500 BP means 1450 AD.

The development of radiocarbon dating has had a profound impact on archaeology. In addition to permitting more accurate dating within archaeological sites than did previous methods, it allows comparison of dates of events across great distances. Histories of archaeology often refer to its impact as the "radiocarbon revolution". Occasionally, the method is used for items of popular interest such as the Shroud of Turin, which is claimed to show an image of the body of Jesus Christ. A sample of linen from the shroud was tested in 1988 and found to date from the 13th or 14th century, casting doubt on its authenticity.[1]