Highlighting the History of French Radio Astronomy. 7: The Genesis of the Institute of Astronomy at Millimeter Wavelengths (IRAM)

Radio astronomy in France and in Germany started around 1950. France was then building interferometers and Germany large single dishes, so it was not unexpected that their first projects involving millimetre radio astronomy were respectively with an interferometer and a single dish. In this paper, we explain in detail how these two projects finally merged in 1979 with the formation of the Institute of Radio Astronomy at Millimetre Wavelengths (IRAM), after a long process with many ups and downs. We also describe how Spain started radio astronomy by joining IRAM. Presently, IRAM is the most powerful facility worldwide for millimetre radio astronomy.

We wish to dedicate our paper to the memory of Émile-Jacques Blum (1923-2009), who played a major role in the construction of IRAM but died before he could participate in the writing of this paper. An interview made one month before his death was very useful in the preparation of this paper.