The book "The Alabama and the Kearsarge" by William Marvel makes mention of a Michael [AKA Martin] Ahern who was one of several Irish recruited in Queenstown, county Cork, in contravention of the Foreign Enlistment Act. This Ahern had been a clerk in civilian life and was rated as paymaster's steward on the Kearsarge. The following is a quote from Marvel's book:

...There was, however, the matter of Michael Ahern. Ahern had been born and raised in Queenstown, where he supported himself as a writing clerk. He had been one of the recruits smuggled aboard in that port the previous November, enlisting as a landsman, but before the ship left Brest to return the "stowaways," he had found a niche as Paymaster Smith's steward, doubling as a second clerk. Ahern was the only one of the Queenstown men who did not return ashore in the pilot boat. ... six days after the battle Winslow specially commended a number of crewmen in a dispatch to Washington, among them "Michael Ahern, paymaster's steward," who later received a Medal of Honor for his conduct. ...

I believe Marvel is correct that the "Aheam" who was awarded the MoH as a paymaster's steward is the Ahern from Queenstown. Variations of the spelling as Ahern or Ahearn are common. I have also seen "Ahern" mistranscribed as "Ahem" in an index to passengers arriving at Ellis Island, but when you look at the manifest itself, it's quite clear that the indexer mistook a tightly written "rn" for an "m". I believe this is what happened in the case of this Ahern.

Where can I find original records that would document the award of the Medal of Honor to Michael Aheam [sic]?

I am not related to the Aherns of Queenstown, but I know Aherns who are. Aherns have been harbor pilots in Queenstown [now Cobh] for generations and I maintain a website about Aherns on which I would like to document the story of the Michael Ahern who was awarded the Medal of Honor for his service on the Kearsarge.

-dja