From ScienceMag: “Neutron Star Provides Direct Evidence for Bizarre Type of Nuclear Matter”

At the site Science Now,

“For more than 50 years, astrophysicists have speculated that inside a superdense neutron star, nuclear matter might flow without any resistance whatsoever—much like electricity does in earthy materials known as superconductors. Now, two teams say they have direct evidence of such bizarre “superfluidity” in a neutron star, and other researchers seem convinced. ‘I think it’s a defensible claim,’ says theorist Krishna Rajagopal of the Massachusetts Institute of Technology in Cambridge. ‘The only explanation [of the observation] that I’m aware of is the one presented in papers’…

i1
Cool. The neutron star Cassiopeia A is cooling at an alarming rate, and the only way that can happen is if the matter in it is turning into a “superfluid,” two teams report.
Credit: X-ray: NASA/CXC/xx; Optical: NASA/STScI; Illustration: NAS

“Now, two teams of physicists (Dany Page, a theoretical astrophysicist and his colleagues at the National Autonomous University of Mexico in Mexico City with Andrew Steiner, a nuclear astrophysicist at Michigan State University in East Lansing; Wynn Ho of the University of Southampton in the United Kingdom and Craig Heinke of the University of Alberta in Edmonton, Canada),say they have more direct evidence for superfluidity in the heart of a neutron star. The data come from NASA’s orbiting Chandra X-ray Observatory, which between 2000 and 2009 took occasional observations of Cassiopeia A (Cas A), a neutron star 11,000 light-years from Earth. The youngest known neutron star in the Milky Way, Cas A was born in a supernova explosion that astronomers may have spotted 330 years ago. The observations show that its temperature is falling at an alarming rate: from 2.12 million K to 2.04 million K, or 4%, in 10 years….”

I hope that you will see the full article here.