"赞美诗研究" can be translated into English as "Hymnology" or "Research on Hymns".
Hymnology is a more specialized and technical term, referring to the academic study of hymns, including their history, theology, music, and literary aspects.
Research on Hymns is a more straightforward and descriptive translation, emphasizing the research aspect of studying hymns.
Both translations are acceptable, depending on the context and the level of formality required.