The A-6 Excavation Team was a Human arctic archaeology team, a group from the Earth Sciences Institute, that studied the debris from a Borg sphere found in the Arctic Circle in 2153.
During their excavation they found a pair of Borg drones frozen in the ice and still intact. Not knowing what they had found, the team allowed the Borgs' regeneration process to resuscitate the drones, and were later assimilated.
The team was suppose to check in with the Science Council, and when they didn't after three days, Starfleet was notified and investigated. (ENT: "Regeneration")
The assignment patch for the A-6 Excavation Team read only Arctic Archaeology and the three last names of the team.
Members of the A-6 Team
A forth person was seen onscreen, but wasn't named, and there were nine Human lifesigns on Arctic One when it was first encountered by Enterprise, which suggests that the team was increased from the three members listed on the assignment patch, or that the extra personal are from another organization, or that several other Borg drones were recovered before Arctic One left Earth.