A country store and a famous rabbi
Frederick Reines was born in Paterson, New Jersey, on March 16, 1918, the youngest of four children of Israel and Gussie (Cohen) Reines. His parents were Jewish emigrants from the same small town in Russia who met and married only after arriving in New York. A relative on his father’s side was Rabbi Isaac Jacob Reines, the founder of Mizrachi, the religious Zionist movement. His father, a skilled weaver, started a silk mill after the First World War and later ran a general store in Hillburn, New York, where Fred spent much of his childhood amid Fourth of July fireworks and bandstand music.
His older siblings were serious students: his sister Paula became a doctor and his brothers David and William became lawyers, and their books filled the house. Reines traced his first spark of interest in science to a moment of boredom at religious school, when he curled his hand into a telescope, looked out at the twilight and noticed something odd about the light. It was diffraction, and it began a lifelong fascination with light. He became an Eagle Scout and built crystal radios from scratch.
A singer who chose physics
At Union Hill High School he was at first stronger in literature and history than in science, until a science teacher gave him a key to the laboratory so he could work whenever he liked. Asked by the yearbook what he wanted to become, he wrote: “To be a physicist extraordinaire.” Accepted by MIT, he chose instead the Stevens Institute of Technology in Hoboken after a chance meeting with its admissions officer. He earned an engineering degree in 1939 and a master’s in mathematical physics in 1941.
Music was nearly his career. He sang solo roles with the college chorus, including in Handel’s Messiah, and a voice coach from the Metropolitan Opera gave him lessons free of charge because he could not afford to pay. He decided against professional singing but sang all his life, later with the chorus of the Cleveland Orchestra under Robert Shaw and George Szell. In 1940 he married Sylvia Samuels; they had two children, Robert and Alisa. He completed a doctorate at New York University in 1944 with a thesis on the liquid-drop model of nuclear fission.
Los Alamos
Before he had finished his thesis, Richard Feynman recruited him to the Theoretical Division at Los Alamos, the Manhattan Project laboratory that built the first atomic bombs. Reines stayed fifteen years. He became a group leader in 1946, studied the effects of nuclear blasts, wrote a paper on blast waves with John von Neumann and in 1951 directed Operation Greenhouse, a series of nuclear tests in the Pacific. Partly because of what he saw, he became concerned about radioactive fallout from atmospheric tests and argued for testing underground. In 1958 he was a delegate to the Atoms for Peace conference in Geneva.
Catching the poltergeist
In 1930 Wolfgang Pauli had proposed an invisible, uncharged particle to explain missing energy in radioactive decay. Enrico Fermi named it the neutrino. It interacts so weakly with matter that it can pass through the whole Earth, and in 1934 Hans Bethe and Rudolf Peierls concluded there was no practical way ever to observe one. In 1951 Reines took a sabbatical to think about what physics to do next and decided to try. Why? Because, he later said, everybody said you couldn’t do it.
He teamed up with his Los Alamos colleague Clyde Cowan. Their first plan was to place a detector near an exploding atomic bomb, but they switched to a nuclear reactor, a weaker but steady source of neutrinos. They designed a signature that could be recognised: when an antineutrino from the reactor hits a proton in a tank of liquid, it creates a positron and a neutron. The positron annihilates at once in a flash of gamma rays; a few millionths of a second later, the neutron is captured by cadmium added to the liquid and gives a second flash. A delayed pair of flashes meant a neutrino.
Their first attempt, called Project Poltergeist, at the Hanford reactor in Washington State in 1953, was swamped by cosmic-ray noise. In 1955 they moved to the new Savannah River reactor in South Carolina, setting their detector 11 metres from the core and 12 metres underground. In June 1956 they sent Pauli a telegram: they had found the neutrino.
The detector was a feat of engineering for its time. The Hanford version held about 300 litres of liquid scintillator watched by 90 photomultiplier tubes. At Savannah River the reactor sent a flux of about 1.2 trillion neutrinos through every square centimetre each second, yet so weakly do neutrinos interact that only a tiny fraction were ever caught. When Hans Bethe, who had declared the neutrino unobservable, heard the news, he is said to have replied that you should not believe everything you read in the papers.
Founding neutrino astronomy
Reines devoted the rest of his career to the neutrino. In 1959 he became head of physics at the Case Institute of Technology in Cleveland, where his group built a detector deep in the East Rand gold mine near Johannesburg, South Africa, more than three kilometres underground. On February 23, 1965, it caught the first neutrinos made by cosmic rays striking the atmosphere. Some colleagues objected to working in apartheid South Africa; Reines said science transcended politics.
In 1966 he moved with most of his group to the new University of California, Irvine, as founding dean of physical sciences. His Irvine group helped build the IMB detector, 8,000 tons of water in a salt mine near Cleveland, designed to look for decaying protons. Reines had long hoped to catch neutrinos from an exploding star and labelled some of his detectors “Supernova Early Warning System”. On February 23, 1987, the light of supernova 1987A reached Earth, and IMB, together with Japan’s Kamiokande, recorded a burst of neutrinos from it, the first ever detected from beyond the solar system. The event is regarded as the birth of neutrino astronomy.
A wider search
Reines never stopped looking for new ways to use and test the neutrino. His Irvine group was the first to observe double beta decay, a very rare form of radioactivity, in the laboratory. He searched for the decay of the proton, which would show that ordinary matter is not perfectly stable; studied neutrinos from reactors to test their basic properties; and helped plan DUMAND, an ambitious scheme to use the deep ocean off Hawaii as a giant neutrino detector, a forerunner of today’s large underwater and under-ice neutrino telescopes. He also had ideas for measuring the gravitational constant more precisely and for exploring the brain with ultrasound.
His love of performance never faded. At Los Alamos he sang with the town chorus, appeared in Gilbert and Sullivan operettas and played the lead in Inherit the Wind with the local dramatic society, and he liked to entertain friends with Gilbert and Sullivan lyrics.
What his work gives the world
The neutrino turned out to be one of the most important particles in nature. Neutrinos carry away most of the energy of a collapsing star and stream from the Sun’s core, where nuclear fusion produces the sunlight that sustains life. Because Reines and Cowan proved neutrinos could be caught, scientists now use them to look inside the Sun and exploding stars, and to study the fundamental properties of matter.
His reactor technique also found a practical use he did not plan. The method he and Cowan invented, catching reactor antineutrinos in a liquid and looking for a positron flash followed by a neutron capture, is the basis of detectors developed to monitor nuclear reactors from outside. Because the antineutrino flow reveals a reactor’s power and how its fuel is changing, small detectors placed tens of metres away can track whether a reactor is running and, in principle, whether plutonium is being diverted. A prototype operated automatically at the San Onofre nuclear plant in California from 2003 to 2006, and such detectors are being developed as a possible tool for the International Atomic Energy Agency’s safeguards against the spread of nuclear weapons.
At Irvine, Reines also encouraged some of his students to adapt radiation detectors for medicine, including devices to measure the total dose delivered to a patient’s body during radiation therapy, and he held an appointment as professor of radiological sciences in the university’s medical school.
Jewish heritage
Reines was the American-born son of Russian Jewish immigrants and a great-nephew of one of the founders of religious Zionism. He mentioned the religious school of his childhood and his rabbinic relative in his Nobel autobiography, but he did not write about religious practice in his adult life. His story, of a store-keeper’s son from small-town New York who became a scientist through public schools, scholarships and the help of teachers, is a familiar one among the children of Jewish immigrants of his generation.
Recognition and legacy
Recognition came late. Reines received the National Medal of Science in 1985 and, in 1995, the Nobel Prize in Physics, shared with Martin Perl, for the detection of the neutrino. Clyde Cowan had died in 1974, and the Nobel Prize is not awarded posthumously. Reines remained on the Irvine faculty until the end of his life. He died after a long illness on August 26, 1998, at the university’s medical centre in Orange, California. Frederick Reines Hall, home of physics and astronomy at UC Irvine, is named for him.
His legacy runs from the deepest mines to the edge of the galaxy: a particle once thought impossible to observe is now a working tool of physics, astronomy and nuclear safety.
Sources & further reading
Frederick Reines, Biographical, NobelPrize.org · Frederick Reines, Wikipedia · Reactor monitoring and safeguards using antineutrino detectors (Bowden et al.), arXiv · Frederick Reines, Jewish Virtual Library · Researched from the sources above and checked against them. Spotted an error? Tell us.
A life of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.