* Astronomy

An experiment at the GANIL facility in France is the first to make, observe, identify, and characterize the heaviest isotope yet of hydrogen, H-7, consisting of a lone proton and 6 neutrons.
All of the lighter isotopes of hydrogen have previously been seen: H-1 (ordinary hydrogen), H-2 (deuterium), H-3 (tritium), and H-4 up to H-6. Technically speaking, the H-7 state (like H-4, H-5, and H-6) is not a fully bound nucleus. It is considered a resonance since (besides being very short lived) energy is required to force the extra neutron to adhere to the other nucleons.
In a proper nucleus energy is required to remove a neutron. In the GANIL experiment, a beam of helium-8 ions (themselves quite rare) is smashed into a carbon-12 nucleus residing in a gas of butane. In a few rare occurrences, the He-8 gives one of its protons to the C-12, producing H-7 and N-13, respectively. The H-7 flies apart almost immediately into H-3 and 4 separate neutrons.

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