Andrzej Buras of the Technical University of Munich has been awarded the Max Planck Medal by the German Physical Society for his outstanding contributions to applied quantum field theory, especially in flavour physics and quantum chromodynamics.

Astroparticle physicist Nigel Smith has been appointed to a three-year extension as executive director of SNOLAB in Canada. Smith, who has been in the role since 2009, agreed to remain in position until 31 December 2022, with a search for a successor being revisited during 2020.

Luigi Radicati, one of the eminent Italian theoretical physicists of the past century, passed away on 23 August 2019 in his home in Pisa, about 50 days before his 100th birthday.

Born in Milan, Radicati received his laurea in physics from the University of Torino under the supervision of Enrico Persico in 1943, and became the assistant professor of Eligio Perucca at Torino Polytechnic in 1948. In between this, during the Second World War he was also a member of a partisan division fighting against German occupation.

The years 1951–1953, which Radicati spent as a research fellow at the University of Birmingham in the group of Rudolf Peierls, had a major impact on his training. Then, in 1953 Radicati became a professor of theoretical physics, first at the University of Naples and two years later at the University of Pisa. In 1962 Radicati was finally called to the Scuola Normale Superiore (SNS) in Pisa as one of two professors in the “Classe di scienze”, the other being the great mathematician Ennio De Giorgi. Radicati remained at SNS until 1996, acting as vice-director between 1962 and 1964, and director between 1987 and 1991.

Luigi Radicati can be remembered for two main reasons: the special role that he attributed to symmetries; and the broadness of his interests in physics, as in the relations between physics and other disciplines. His most important and well known physics results stem from the early 1960s. After working with Paolo Franzini to show evidence for SU(4) symmetry in the classification of nuclear states, introduced by Wigner in 1937, in 1964 Radicati proposed, together with Feza Gürsey, the enlargement of SU(4) to SU(6) as a useful symmetry of hadrons. Gell-Mann had introduced the SU(3) symmetry in 1962 and at the beginning of 1964 had proposed, simultaneously with George Zweig, the notion of quarks. The SU(6)-subgroup SU(3) × SU(2) puts together Gell-Mann’s SU(3) with the spin SU(2) symmetry, thus unifying in single multiplets the pseudo-scalar together with the vector mesons and the J = 1/2 together with the J = 3/2 baryons. At a deeper level, SU(6) gave momentum to view the quarks as real entities obeying peculiar statistics, preliminary to the introduction of colour.

In the latter part of the 1960s Radicati began turning his attention to astrophysics, gravity, plasma physics and statistical physics. Here it is worth mentioning the long-lasting collaboration with Emilio Picasso, which started in 1977 during a discussion in the CERN cafeteria: the use of a gravitational-wave detector consisting of a system of two radio-frequency cavities, coupled to create a two-level system with a tunable difference between their oscillation frequencies.

Radicati’s collaborations brought frequent visits of eminent physicists to Pisa, among them Freeman Dyson, Feza Gürsey, T D Lee, Louis Michel, Rudolf Peierls, David Speiser and John Wheeler. Most of all, Radicati played a prominent role in bringing from CERN to the SNS Gilberto Bernardini, who acted as SNS director from 1964 to 1977, and Emilio Picasso, who was SNS director from 1992 to 1996.

Radicati was a member of the Accademia Nazionale dei Lincei from 1966, named Chevalier de la Légion d’Honneur and Doctor Honoris Causa at the École Normale in Paris in 1994, and was awarded the honour of Cavaliere di Gran Croce of the Italian Republic in 2004. During his career, he also translated and introduced important physics books into Italy, including The Meaning of Relativity by Albert Einstein, A History of Science by William Dampier and Quantum Mechanics by Leonard Schiff.

Luigi Radicati is survived by his wife and four of his sons.

Jean-Pierre Blaser, a former director of the Swiss Institute of Nuclear Research (SIN), passed away in his home in Switzerland on 29 August 2019 at the age of 96.

In 1948 Blaser finished his physics studies at ETH Zurich, going on to participate in the development of a cyclotron at ETH built by Paul Scherrer during the Second World War. From 1952–1955 he carried out experiments with mesons at the synchrocyclotron in Pittsburgh before becoming director of the observatory in Neuchâtel from 1955–1959. In 1959 he was appointed as Scherrer’s successor and inherited from him the planning group for a new cyclotron. Originally, Scherrer wanted to copy the 88-inch cyclotron at Berkeley and use it for research in nuclear physics, but Blaser wanted something more ambitious. After receiving advice from accelerator experts at CERN, among them Pierre Lapostolle, he proposed a 500 MeV cyclotron for the production of mesons.

The key for such a meson factory was to extract the high-intensity proton beam with very low losses. The leader of Blaser’s cyclotron group, Hans Willax, realised that a conventional cyclotron would have high losses at extraction and in 1962 had the brilliant idea to break up the cyclotron magnets into separate sectors to leave space for high-voltage cavities. Blaser immediately supported the idea and pushed to get this expensive project approved by the Swiss government. Against all odds and against some strong opposition, he finally succeeded. In 1968 he founded SIN in Villigen and was its director for the next 20 years.

In a last-minute decision, based on results of CERN experiments which showed that the production of pions would strongly increase with energy, the energy of the SIN cyclotron was increased from 500 to 590 MeV. Even top accelerator specialists like the late Henry Blosser had doubts that the SIN crew would reach the ambitious design goal of a 100 μA beam current. But Blaser and Willax were convinced, anticipating that the original 72 MeV injector cyclotron would be the limiting factor and eventually would have to be replaced. In January 1974 the first protons were extracted from the ring, and at the end of 1976 the design current of 100 μA was reached. More highlights followed, right up to 2009 with 2.4 mA protons at 590 MeV and a new world record of 1.4 MW in average beam power achieved – a record that still holds today. These results gave Blaser great satisfaction, even after his retirement in 1990. Before that date he initiated in 1988 the new Paul Scherrer Institute (PSI), a combination of SIN and the neighbouring reactor institute EIR.

From the start of the accelerator project, Blaser saw the potential of particle beams to irradiate tumours. The first step, for which a superconducting solenoid was constructed, was to use pions for the treatment of deep-seated tumours. In 1984 the irradiation of eye tumours started, using protons, and to date more than 7000 patients have been treated. Later, a new superconducting cyclotron was acquired and two more gantries are now in operation. Blaser strongly supported all activities in the medical application of cyclotrons, and gave his advice to a new cyclotron project in South Africa – becoming elected as a foreign associate of the Royal Society of South Africa for his efforts.

Jean-Pierre Blaser was blessed with great intuition based on a thorough knowledge of the basic laws of physics. He was open to new and unconventional ideas and he fully motivated young scientists with his trust in their abilities. In his free time he enjoyed exploring the landscapes of Switzerland either by foot or as a pilot with a light aeroplane. But his top priority was his family. He enjoyed enormously the company of his wife Frauke, their two daughters Claudine and Nicole, and their four grandchildren. In Jean-Pierre, his family and the accelerator community loses a great personality.

Badanaval Venkatasubba Sreekantan, a pioneering cosmic-ray physicist and a member of Homi Bhabha’s team of scientists, who played an important role in the development of post-colonial Indian science, died at his home in Bangalore on 27 October 2019.

Sreekantan was born on 30 June 1925 near Mysore in South India. After receiving his master’s degree in physics in 1947 with a specialisation in wireless technology from Mysore University, he joined the Indian Institute of Science at Bengaluru as a research scholar, where he heard about Bhabha and his newly formed Tata Institute of Fundamental Research (TIFR) in Mumbai. Attracted by Bhabha’s charisma, he joined TIFR in July 1948 and began a long, illustrious scientific career of almost 44 years.

In 1951 Bhabha sent Sreekantan down the deep Champion Reef Gold Mine at Kolar Gold Fields (KGF) near Bengaluru to measure the flux of cosmic-ray muons at varying depths. This pioneering initiative not only earned Sreekantan a PhD but also paved the way for setting up a deep underground laboratory. A series of follow-up experiments at KGF, carried out during the early 1960s, extended his previous measurements of muon intensity to the deepest level available; finally, after reaching a depth of 2700 m, recording no muons after two months of exposure. Sreekantan and his collaborators realised that such a deep underground site with minimal cosmic-ray muon background would be an ideal site to detect atmospheric neutrinos. A series of seven neutrino telescopes were quickly set up at a depth of 2300 m and in early 1965 they recorded the first atmospheric-neutrino event, contemporaneously with the detection from another underground neutrino experiment set up by Fred Reines in a South African mine. It was an important milestone, given how important the study of neutrinos underground would later become.

During early 1980s Sreekantan and his collaborators built two detectors, one at a depth of 2300 m and the other at 2000 m, to study the stability of the proton. These two experiments ran for more than a decade and put strong limits on the proton lifetime. He was also instrumental in starting a high-altitude cosmic-ray laboratory at Udhagamandalam (Ooty) in the State of Tamil Nadu to study the hadronic components of cosmic-ray showers.

Sreekantan quickly recognised the importance of the emerging field of X-ray astronomy for probing high-energy processes in the universe. In 1967 he started balloon-borne experiments to study cosmic X-ray sources and built a strong group that went on to develop expertise in the fabrication of highly sophisticated X-ray detectors for space-borne astronomy missions. The multi-wavelength astronomy observatory Astrosat, launched by the Indian Space Research Organisation in September 2015, is a testimony to the strength of the group. A very high-energy gamma-ray observation programme using the atmospheric Cherenkov technique, which was started by Sreekantan and his collaborators in Ooty in the 1970s, is being continued in Ladakh with a low-energy threshold.

Sreekantan became director of TIFR in 1975, and over the next 12 years steered the institute with distinction and left a rich legacy of high-quality research programmes as well as several new TIFR centres and field stations. In 1992, after a long and eventful scientific carrier at TIFR, Sreekantan moved to Bengaluru and was offered a chair at the newly created National Institute of Advance Studies. His research interest shifted from physical sciences to the philosophical aspects of science and in particular to the abstract topic of consciousness and its scientific and philosophical basis. He remained an alert and active researcher and was engaged in his academic activities with great eagerness until the very end. His death marks the end of a glorious chapter of experimental cosmic-ray research in India.