Is user Researcher same as UX researcher?
UX Research, or User Research is a structured study of users, their needs and requirements, which work in tandem with the design process. UX Researchers use a plethora of methods and techniques, to reveal issues and opportunities that can be fed back into the design. Research is a hugely broad term.
Can you do UI without UX?
It's important to understand that UX and UI do go hand-in-hand; you can't have one without the other. However, you don't need to possess UI design skills to be a UX designer, and vice versa—UX and UI constitute separate roles with separate processes and tasks!