A team of physicists using an extremely sensitive particle physics detector, called the Alpha Magnetic Spectrometer (AMS), just might have discovered something which has eluded scientists ever since they were first theorized to exist: dark matter particles. On September 18, the findings of the team were published in the journal Physical Review Letters. Also, the scientists presented their data and other findings during a meeting of the European Organization for Nuclear Research, or CERN.
The International Space Station (ISS) is where the very sensitive spectrometer, the AMS, is located. The AMS has, so far, detected a vast number of space particles, 41 billion of them. The information that the AMS has collected has given physicists knowledge about what sorts of particles cosmic rays beyond Earth are composed of and the AMS just might have detected positrons within these cosmic rays.
Positrons which have been exposed to high energy levels, according to an article at the Chinatopix site, are dark matter’s equivalent to electrons in atoms. Positrons, as their name suggests, have a positive charge, while electrons have negative charges. Positrons and electrons have the same mass. There have been far fewer positrons discovered within these cosmic rays at very high energy levels of 275 gigaelectronvolts.
Some scientists believe that positrons might have their origins in pulsars, or other extremely dense stars. Also, it is possible that positrons, in some cases, originate from collisions of antimatter, according to a report in Tech Times. The AMS aboard the ISS just might help physicists explain more about the origins of positrons and antimatter.
Because it is a fact that gravity has an influence on visible matter, CERN suggests, according to the Chinatopix article, that the presence of positrons at high energy levels could lead to proving that dark matter exists. Something is exerting gravity on the matter that is visible, and this effect has been noted by scientists. This “something,” is, according to many physicists, dark energy, dark matter and antimatter.
According to assistant professor of physics at MIT Paolo Zuccon, the information that has been collected using the AMS has shown “that a new source of positrons is active in the galaxy.” Zuccon added that “measurements are underway by AMS,” which might lead to a clearer determination of where the “new source” of positrons is coming from, pulsars or possibly from the collision of dark matter.
For something which scientists believe might possibly make up around 85 percent of the universe, dark matter, there is very little that is known about it. Dark matter and antimatter have never actually been seen by scientists. Rather, scientists have observed how antimatter appears to effect the universe and they have developed theories about what it is like based on this knowledge. Using the AMS, scientists might be able to discover more about the origins of antimatter and dark matter and other information about these mysterious substances.
Zuccon has unequivocally stated that “Dark matter is there.” It is just that it has never been seen before. However, the new data collected by the AMS, a project that cost $2 billion, is one of several pieces of evidence scientists have been accumulating that indicates that dark matter exists.
Dark matter has not ever been seen and does not emit radiation. It also absorbs light, making it very difficult to detect. According to Samuel Ting, who is the AMS team’s project leader as well as being a Nobel Laureate from MIT, despite the fact that dark matter has never been seen, the data that the AMS has collected will likely prove useful to scientists in learning more about the substance. The data that AMS collects over the next decade, scientists hope, will provide further evidence that cosmic rays at higher energy levels contain the type of positrons in dark matter.
According to a report by Q13 Fox, “only about 4%” of the universe is composed of “the kind of matter and energy we can perceive.” From that minute amount of matter that scientists have been able to observe, they have developed several theories about the rest of the universe that exists, including theories about the existence of antimatter, dark energy and dark matter.
Many physicists believe that over 70 percent of the universe is composed of dark energy, while dark matter likely makes up over 20 percent. Dark energy and dark matter have been theorized to exist, in part, because of the data gathered about the effect of the gravity they exert upon visible matter.
Being able to examine positrons in detail, with the help of the AMS aboard the ISS, might provide physicists with the information they need to prove that dark matter exists. For the first time in 50 years of researching cosmic rays, thanks to data gathered by the AMS, a peak in the fluctuation of positrons in cosmic rays has been observed and measured, according to the report by Q13 Fox.
More research and study of the positrons that have been measured within the cosmic rays is needed, according to CERN, but the particles that the AMS has discovered appear to be “consistent with dark matter particles.” If the particles are proven to be dark matter, possibly scientists will slowly begin to reveal information about the 96 percent of the universe that has remained, thus far, elusive and invisible to them.
Written By Douglas Cobb