This $2B Cosmic Ray Detector Is Unravelling the Secrets of the Universe

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Finding the Higgs Boson particle is a revolutionary scientific discovery, sure, but CERN isn't the only scientific body rewriting our understanding of elementary physics. An international team of researchers have just announced that the massive cosmic ray detector protruding from the ISS may have at long last detected dark matter.

The cosmic ray detector is called the Alpha Magnetic Spectrometer (AMS). It is the result of a collaboration of more than 200 scientists from 16 countries led by MIT physicist and Nobel laureate Samuel Ting. The DoE sponsored the $2 billion endeavor whose development began back in 1995 with the death of the Superconducting Super Collider program. The AMS was built at ESA's European Space Research and Technology Centre (ESTEC), rigorously tested under the CERN's nuclear particle beams, and delivered to the ISS from the Kennedy Space Center aboard the Space Shuttle Endeavor in 2011. With a peak power draw of 2.5kW, launching the AMS as an independent satellite proved unfeasible, hence its installation aboard the ISS.

The AMS is designed to pick out specific unusual particles from the haze of cosmic background radiation. As of July 2012, the detector had logged more than 18 billion cosmic ray events—that's roughly a thousand cosmic ray events every second, generating more than a gigabyte of data in the same amount of time. Among those 18 billion events, the AMS also recorded some 400,000 positrons—the antimatter ying to an electron's yang—however, the energy readings of these positrons suggest that they're the result of dark matter/anti-matter pairs annihilating each other rather than being created in, say, a pulsar or Lawrence Livermore Lab.


This is huge news because, as its name implies, dark matter can only be observed indirectly even though it theoretically constitutes 80 percent of the known universe. Physicists have long speculated that this dark matter is composed of Weakly Interacting Massive Particles (WIMPs), theoretical particles that only interact using the weak force rather than electromagnetic force (which prevents them from being directly observed). Since WIMPs generally keep to themselves, they are their own antimatter particle partners and will annihilate one another on contact, resulting in an electron and the positrons discovered by the AMS.


A lot more data needs to be collected and analyzed before researchers can say for certain if the positrons are the result of WIMP interaction but this discovery is an huge step forward in our growing understanding of how the Universe was created and, more importantly, what it's made of.

[Space 1, 2 - NASA - Wikipedia - AMS - Images: NASA]