Sylvia Plath was a lifelong anti-smoker, though she did begin to smoke in the last six months or so of her life. (Ted Hughes mentions in his letters how much this surprised him).
Since Sylvia never really had time to settle in to smoking it is likely she would have smoked mild cigarettes - perhaps Embassy, Strand, or Guards.
She would not have been smoking Senior Service or Capstan.
Sylvia Plath was known to smoke Parliament brand cigarettes.
Newports
Newports.
Don't smoke, it's terrible for you.
He smoke Virginia slims or Marlboro
As of January 2014, the singer Shakira does smoke cigarettes. The name of the cigarettes are Kool 100's.
PARLIMENT
None
Baskets.
Newports.
Marlboro reds
Virginia Slims
i believe Parliaments.