user: Question: What is the decay mode of the 265m Hs isotope discovered in 1984?
Columns: ['Isotope', 'Half-life', 'Decay mode', 'Discovery year', 'Reaction']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['263 Hs', '0.74 ms', 'α, SF', '2008', '208 Pb( 56 Fe,n)']
SQL:

assistant: SELECT "Decay mode" FROM "Table" WHERE "Discovery year" = '1984' AND "Isotope" = '265m Hs';