Inside Hiroshima University's largest research partnership: The University of Tokyo

Behind Hiroshima University's research output sits a defining relationship: 1,308 co-authored works with The University of Tokyo (Japan) in the five years to 2025, the university's single largest collaboration.

It anchors an unusually connected research base: 1,067 collaborating institutions across 76 countries, producing 23,151 joint works over the window, with international co-authors on 27% of output.

The collaborative work travels: its field-weighted citation impact stands at 2.0, where the world average is 1.0.

The Research Collaboration Index, the first global account of how universities actually collaborate, publishes its first full edition on Tuesday 15 September at 09:00 UK.

Every figure derives from the open global research record and is checkable at source.