I think technically yes, but it has to be played on windows or in the browser, per the jam rules. However, I high advise against it since people will likely not want to install core just to rate your game.

IMPORTANT EDIT: No. You camnot.

From the jam rules:

"Also know that linking to an external site will disqualify you from the jam. So make sure your game is uploaded to itch.io if you want to participate."

From what I know, Core is a system where you have to have an account and install it to play other games. So no, you cannot use core. However, a game jam is a great time to learn a new engine like Unity or Unreal(which Core is based on).