Goran Senjanović

Who is Goran Senjanović?

Goran Senjanović is a theoretical physicist at the Abdus Salam International Centre for Theoretical Physics. He received his Ph.D. at the City College of New York in 1978, under the supervision of Rabindra Mohapatra. Before joining the ICTP in 1991, he worked as a staff member at the Brookhaven National Laboratory and as a professor of physics at the University of Zagreb. His major research interests are neutrino physics, unification of elementary particle forces, baryon and lepton number violation and supersymmetry.

Senjanović is best known for the seesaw mechanism, which he proposed together with Rabindra Mohapatra in 1979, independently of Peter Minkowski, Sheldon Lee Glashow, Murray Gell-Mann, Pierre Ramond, Richard Slansky and Tsutomu Yanagida. The seesaw mechanism is today the main scenario behind the mystery of tiny neutrino mass. According to this mechanism, the origin of neutrino mass is attributed to the existence of its heavy right-handed neutrino. In the works of Minkowski, and Mohapatra and Senjanovic, the smallness of neutrino mass is related to the maximality of parity violation in weak interactions.

Senjanović, together with Mohapatra, Jogesh Pati and Abdus Salam, is one of the proponents of the left-right symmetric theory of electroweak interactions, introduced in order to understand the origin of parity violation in nature. In this theory, the left-right symmetry is broken spontaneously, which allows for its restoration at high energies. In this context, in a paper with Wai-Yee Keung in 1983, he proposed a way to directly probe lepton number violation and test the Majorana nature of right-handed neutrinos at hadron colliders, today a paradigm for such processes at the Large Hadron Collider at CERN.