Vamsa is nothing but lineage of acharyas. Mostly this vamsa is lineage of rishis getting the upadesha ( teaching about parabramha or on any subject ) from some other rishis . In most of vamasas lineage of bramhavidya is mentioned ( yet shatpatha bramhana gives vamsa for yagniki vidya )
Another important point is that all lineages start from bramha ( some times he is also called svayabhu bramha , sometimes prajapati, )
Like all other traditions of Rigvedis (shankhayan) ,Suklayajurvedis having vamsa starting from svayambhu bramha,Krishna yajurvedis ,Samavedis having a bramhana dedicated to vamsa ( Vamsa bramhana ) .Atharvans have there vamsa too. These vamsa is mentioned in Mundaka upanishad.
Starting from Bramha to shaunak maharshi, acharyas mentioned in vamsa are enlisted below :
(1) Bramha ( viswasya karta bhuvanasya gopta )
(2) Atharva ( Eldest son of Bramha )
(4) Satyavaha bharadwaja
( shaunak mahashal )
This is lineage of seekers and seers of bramhavidya in accordance with atharvan tradition. Like all other traditions of north India ( mostly of shukla yajurvedis ), oblations are offered to all this acharyas by Atharvans on upakarma day.