放ほう射しゃ線せん分ぶん解かい

Meanings

1

radiolysis

Technical term in chemistry and physics for the decomposition of chemical compounds by ionizing radiation.

unravel, notes, key

放ほう射しゃ線せん
放射線 means 'radiation' itself, while 放射線分解 refers specifically to the decomposition caused by radiation.
分ぶん解かい
分解 is a general term for 'decomposition' or 'disassembly'; 放射線分解 specifies decomposition induced by radiation.

Compound of 放射線 (radiation) and 分解 (decomposition).