Is it possible to send the same survey, but with different headers, to different groups?

Yes, you can pass the value for the header as an embedded data field and then pipe that value in

Thank you for your response! My apologies in advance if my responses are clumsy and/or ill-informed. I would describe myself as a novice when it comes to Qualtrics. If the value for the header is the title of the session, and there are approx. 50 different session titles, each one needing to go to a different group of respondents (via email), from where are the values being piped, and how could the survey be distributed to different groups depending on the session title (header)?

Sorry for the double comment, but maybe you can comment on whether what I'm thinking would work, or if there is a better way to do this. Let's say instead of distributing via email, I do so by link, since it really can be anonymous within each group. If I create a query string for the header (session title) and distribute the unique URLs to individuals in the group for that session, I could then have the header pipe in as embedded data for a block header. The data would then show which session the responses are for based on the header. Is there a better way of doing this? This works, only I would still have to create a unique URL for each session and manually send it to individuals in that group. It would be nice to have the contact info uploaded and involved somehow in the process.

I suggest you create a contact list for each session and upload into Directory. I'm assuming sessions are happening at different times and you want to send invites at different times, hence the separate contact lists.
Within that contact list you'll have a field called something like "Session Name". Make sure this field is also created in the survey Survey Flow as embedded data. That's the field you'll pipe into the header, and it'll automatically populate from your contact list.
You'll distribute via Email from Distributions tab in the survey to each contact list. It'll automatically grab the embedded data field value from contact list and populate into survey.

Thank you! I think your suggestion will work best.