In general, if you are working for a company and the job requires research, you report the research as work (because you cannot do your job without it and in some cases your work IS research).
Presumably you and your supervisor knew this would require research elements ahead of time so this would apply to you.
In your situation, talk with your supervisor ASAP about this specific question. This is for four key reasons.
- First, if you don't report 50% of your hours, your supervisor will have no idea how much actual time it takes you to do your work, and perhaps assign you too much work. You will have a harder time the longer this goes on and your supervisor will have no idea you were working 2x or 3x your reported hours.
- Second, your supervisor might be able to help you with that process or know information which can help you in your process.
- Third, you get on the same page as your supervisor regarding what your actual work entails. Research work often has lots of time with minimal "visualized" results. You can discuss this specific question with him/her and make yourself feel better in reporting hours used for research. If you do report 90% research hours, without confirmation from your supervisor, you probably will always wonder, "should I have really reported these hours?" but asking and getting an answer from the source takes away that wonder.
- Fourth, the longer you delay this conversation, the more difficult it gets to have. If you don't report research hours for weeks or months you are setting an expectation to your boss (similar to #1) which is that you are able to do the work required for 2x the time in 1/2 the time. Whereas talking on the first pay period makes this a really easy conversation, etc.
Additionally, none of us know the details of your interaction, your contract, or the specifics of the job, so it is really difficult to definitively answer. But the person who CAN answer definitively is your supervisor.