Elusive tetraneutron is discovered at Japanese lab – Physics World - physicsworld.com

Nucleus-like four neutron entity exists very briefly as a “resonance”

Resonant state: the tetraneutron has been discovered at long last (Courtesy: Shutterstock/paul_june) A four-neutron particle called a tetraneutron, which forms very briefly as a resonance, has been … [+5185 chars]

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