rational elliptic curve: torsion subgroup defined over abelian extensions

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I'm thinking about a question, that is if E is a rational elliptic curve, K is a cyclotomic field, how can I find the minimal subfield of K such that the torsion subgroup over K can also be defined over this subfield? I have found some papers for classification of torsion subgroups over Q^ab, quadratic fields, I wonder if there is connection between them? Thanks a lot.