M. G. K. Menon (1928-2016).

M ambillikalathil Govind Kumar Menon (MGK or Goku to friends) passed away peacefully on 22 November 2016 at his residence in New Delhi, India. He was 88 years old. Menon made pioneering contributions to particle physics and successfully implemented a grand vision for the scientific and technological growth of India. Born in Mangalore, India, Menon received a B.S. degree from Jaswant College, Jodhpur, in 1946. After being inspired by Sir Chandrasekhara Venkata Raman, an Indian physicist and Nobel laureate, Menon studied physics under the tutelage of spectroscopist Nanasaheb Ramji Tawde at the Royal Institute of Science Bombay, where he earned his M.Sc. degree. For his doctoral work, he joined the laboratory of Cecil F. Powell, soon-to-be Nobel laureate, at the University of Bristol, England, in 1949. By the time Menon arrived in Bristol, the existence of the pion, the subatomic particle mediating nuclear forces, had been clearly established by Powell. Menon’s first important contribution was to establish the bosonic character of the pion through a study of fragments emerging from pion capture by light nuclei in nuclear emulsions. The capture events he recorded also allowed a study of nuclear evaporation models that explain the emission of lighter fragments by nuclei at a high excitation energy of ~140 MeV. Menon then focused his attention on the emerging field of K-meson physics. With his colleagues at Bristol, notably Peter Fowler, Cecil Powell, and Cormac O’Ceallaigh, he discovered that kaons decay into either two or three pions. This puzzling observation generated much discussion and debate and led to the discovery of parity nonconservation in weak interactions. Menon continued his work and built up a sizeable collection of events showing the “associated production” of kaons and hyperons. In 1955, Menon was invited to join the Tata Institute of Fundamental Research (TIFR) in Mumbai, India, by its founding director and nuclear physicist Homi J. Bhabha. Menon seamlessly integrated into the programs related to cosmic rays and helped to enhance the capabilities of scientific ballooning, in which large plastic balloons carry instruments to stratospheric heights to observe extraterrestrial radiation. This suborbital program not only led to rapid progress in cosmic-ray physics but also served as the pre-