Achieving copulations with Red Admiral indoors

Hey everyone

I am raising V. atalanta (Red admirals) for a research project on butterfly migration. Therefore I am trying to keep butterflies throughout the winter, right now I have about 50 adults that I raised during summer. I am wondering what the best way forward is in order to get a new generation. I live in cold Norway so my only option is to do everything inside during the colder months.

My main questions are following:
- Do they mate by themselves if kept warm and in light, and with their host plant?
- Is hand-pairing necessary, or an option?
- Does anyone know the best way to tell apart females and males?
- What are the best environmental conditions to keep them, eg. temperature, light etc.

If anyone has previous experince with this species during winter I would love to hear what you did!

Kind regards
Peik