omg, trying to get my tongue around the occupations in this section is doing my head in.
A researcher is someone who conducts research, i.e., an organized and systematic investigation into something. An investigator is a person who carries out a formal inquiry or investigation. In English I believe it would be okay, although I would generally use investigator when referring to looking into a criminal offense or something of that nature. I'm going to assume Italian has two separate words one for researcher and one for investigator. Google translate lists: investigatore(-trice), and il indagatore. https://www.google.ca/amp/s/www.collinsdictionary.com/amp/english-italian/investigator https://www.collinsdictionary.com/dictionary/english-italian/researcher Those links give sample sentences in English which show how the usage of the words is different despite their similar definitions.