'Doubly magic' form of oxygen may challenge a fundamental law of physics

For the first time, scientists have created oxygen-28, a rare oxygen isotope that has 12 more neutrons than oxygen-16, the most common form of oxygen on the planet. This newly created "heavy" oxygen isotope has the highest number of neutrons ever seen in an oxygen atom and was expected to be ultrastable and last virtually forever. Instead, however, it degraded incredibly quickly — a finding that challenges our understanding of the strong force, which binds the fundamental particles of matter, such as protons and neutrons, to form larger particles in an atom's nucleus.

In a separate case, scientists in 2009 showed that an oxygen-24 isotope behaved as though it were doubly magic, even though it did not have a magic number of protons and neutrons.  See also:

Super-heavy oxygen hints at problem with the laws of physics