Related Clues:

• Scintillas
• Split bit
• Tiny power source
• Physics bits
• Fermi's bits
• Itsy bits
• Elemental unit
• Symbol of the post-1945 age
• Chemistry bit
• Molecular components
• Units in physics
• Film director Egoyan
• Tiny things
• With 28-Across, particle accelerators
• Elemental building block