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Nobel 1990

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Deep Inelastic Scattering: Comparisons with the Quark Model

Deep Inelastic Scattering: Experiments on the Proton and the Observation of Scaling

Deep Inelastic Scattering: The Early Years

"for their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics"

Jerome I. Friedman	Henry W. Kendall	Richard E. Taylor

1/3 of the prize	1/3 of the prize	1/3 of the prize
USA	USA	Canada
Massachusetts Institute of Technology (MIT) Cambridge, MA, USA	Massachusetts Institute of Technology (MIT) Cambridge, MA, USA	Stanford University Stanford, CA, USA
b. 1930	b. 1926 d. 1999	b. 1929

Autobiography: Jerome I. Friedman

I was born in Chicago, Illinois on March 28, 1930, the second of two children of Selig and Lillian Friedman, nee Warsaw, who were immigrants from Russia. My father came to the United States in 1913 and later served in the U.S. Army Artillery Corps in World War I. After the war he was employed by the Singer Sewing Machine Co. and later established his own business, repairing and selling used commercial and home sewing machines. My mother arrived in the United States in 1914 on one of the last voyages of the Lusitania. She supported herself until she was married by working in a garment factory. My parents had little formal education, except for courses in English after they arrived in the United States, but were self taught and had wide ranging interests. My father was an avid reader, having interests in science and political history, and our home was filled with books. My mother, who had a lovely singing voice, loved music and, in particular, opera. The education of my brother and myself was of paramount importance to my parents, and in addition to their strong encouragement, they were prepared to make any sacrifice to further our intellectual development. When there were financial difficulties they still managed to provide us with music and art lessons. They greatly respected scholarship in itself, but they also impressed upon us that there were great opportunities available for those who were well educated. I received my primary and secondary education in Chicago. As I very much liked to draw and paint as a child, I entered a special art program in high school, which was very much like being in an art school imbedded in a regular high school curriculum. While I always had some interest in science, I developed a strong interest in physics when I was in high school as a result of reading a short book entitled Relativity, by Einstein. It opened a new vista for me and deepened my curiosity about the physical world. Instead of accepting a scholarship to the Art Institute of Chicago Museum School and against the strong advice of my art teacher, I decided to continue my formal education and sought admission to the University of Chicago because of its excellent reputation and because Enrico Fermi taught there. I was fortunate to have been accepted with a full scholarship. As my parents had limited means, my university training would not have been possible without such help. After finishing my requirements in an highly innovative and intellectually stimulating liberal arts program (established by Robert M. Hutchins who was then President of the University), I entered the Physics Department in 1950, receiving a Master's degree in 1953 and a Ph.D. in 1956. It is difficult to convey the sense of excitement that pervaded the Department at that time. Fermi's brilliance, his stimulating, crystal clear lectures that he gave in numerous seminars and courses, the outstanding faculty in the Department, the many notable physicists who frequently came to visit Fermi, and the pioneering investigations of pion proton scattering at the newly constructed cyclotron all combined to create an especially lively atmosphere. I was indeed fortunate to have seen the practice of physics carried out at its "very best" at such an early stage in my development. I also had the great privilege of being supervised by Fermi, and I can remember being overwhelmed with a sense of my good fortune to have been given the opportunity to work for this great man. It was a remarkably stimulating experience that shaped the way I think about physics. My thesis project was an investigation in nuclear emulsion of proton polarization produced in scattering from nuclei at cyclotron energies. The objective was to determine whether the polarization resulted from elastic or inelastic scattering. Professor Fermi tragically died in 1954 after a short illness. What an immense loss it was to all of us. My thesis work was not yet completed, and John Marshall kindly took over my supervision and signed my thesis. After I received my Ph.D., I continued working as a post-doc at the University of Chicago nuclear emulsion laboratory, which was then led by Valentine Telegdi. That year Val Telegdi and I did an emulsion experiment in which we searched for parity violation in muon decay. We were one of the first groups to observe this surprising effect which had been suggested by T.D. Lee and C.N. Yang. Val was not only an excellent mentor but he was instrumental in getting me my first real job with Robert Hofstadter.

In 1957, I joined Hofstadter's group at the High Energy Physics Laboratory at Stanford University as a Research Associate. This was where I learned counter physics and the techniques of electron scattering. While there I did a number of experiments studying elastic and inelastic electrondeuteron scattering. In an experiment to measure a weighted sum-rule for inelastic electron deuteron scattering which was related to the n-p interaction I had to confront the problem of making radiative corrections to inelastic spectra, and I developed a technique which proved to be valuable in my later work. Henry Kendall independently developed a similar technique and later we combined efforts to develop a radiative corrections program for our deep inelastic scattering work at SLAC. It was in Hofstadter's group that I began my long collaboration with Henry Kendall who was also a member of the group. During this period I became acquainted with Richard Taylor, who was just finishing his thesis in another group, and with other future collaborators in the deep inelastic program at SLAC, Dave Coward and Hobey DeStacbler. One of the highlights of this period was attending the wonderfully informal and informative high energy physics seminars in the home of W.K.H. Panofsky, who was Director of the Laboratory.

In 1960, I was hired as a faculty member in the Physics Department of the Massachusetts Institute of Technology. When I arrived I joined David Ritson's research group. A short time later he accepted a position at Stanford University and I inherited a small group. With these resources I soon began working on collaborative effort to measure muon pair production at the Cambridge Electron Accelerator (CEA) in order to test the validity of Quantum Electro-Dynamics. Henry Kendall joined my group in 1961 and we have been collaborators at MIT since that time. The last measurement we did at the CEA was a measurement of the deuteron form factor at the highest momentum transfers that could be reached at that accelerator to get some limits on the size of relativistic effects and meson currents.

In 1963, Henry Kendall and I started a collaboration with W.K.H. Panofsky, Richard Taylor and other physicists from the Stanford Linear Accelerator Center and the California Institute of Technology to develop electron scattering facilities for a physics program at the Stanford Linear Accelerator, a 20 GeV electron linac that was being constructed under the leadership of Panofsky. This required that we both travel between MIT and SLAC on a regular basis. The MIT Physics Department gave us special support by reducing our teaching responsibilities. We soon set up a small MIT group at SLAC and for extended periods of time one of us was always there. We had a rare opportunity. We were part of a group of physicists who were provided a new accelerator, given the support to design and construct optimal experimental facilities, and had the opportunity to participate in the exploration of a new energy range with electrons. From 1967 to about 1975 the MIT and SLAC groups carried out a series of measurements of inelastic electron scattering from the proton and neutron which provided the first direct evidence of the quark sub-structure of the nucleon. It was a very exciting time for all of us. This program is described in detail in the adjoining Physics Nobel Lectures.

As the program at SLAC was nearing completion we joined a collaborative effort at Fermilab involving a number of institutions to build a beam line and a single-arm spectrometer in the Meson Laboratory. During the latter half of the 1970's this collaboration carried out a series of experiments to investigate elastic scattering, Feynman scaling and production mechanisms in inclusive hadron scattering. When this work was completed, our group joined another collaboration to build a large neutrino detector at Fermilab. The objective of this program was to study the weak neutral currents in measurements of inclusive neutrino and anti-neutrino nucleon scattering, which were done in the first half of the 1980's. These investigations confirmed the predictions of the Standard Model.

In 1980, I became Director of the Laboratory for Nuclear Science at MIT and then served as Head of the Physics Department from 1983 to 1988. During the time I was in these administrative positions I managed to maintain a foothold in research, which greatly eased my transition back to full-time teaching and research in 1988. While it was a very interesting period in my life, I was happy to get back to more direct contact with students in the classroom and in my research projects. Currently, our MIT group is participating in the construction of a large detector to study electron-positron annihilations at the Stanford Linear Collider and has also been engaged in design work for a detector for the Superconducting Super Collider, which is now under construction.

Over the years I have served on a number of program and scientific policy advisory committees at various accelerators. I also was a member of the Board of the University Research Association for six years, serving as Vice President for three years. I am currently a member of the High Energy Advisory Panel for the Department of Energy and also Chairman of the Scientific Policy Committee of the Superconducting Super Collider Laboratory.

Experimental high energy physics research is a group effort. I have been very fortunate to have had outstanding students and colleagues who have made invaluable contributions to the research with which I have been associated. I thank them not only for their contributions, but also for their friendship.

My life has been enhanced by my marriage to Tania Letetsky-Baranovsky who has broadened my horizons and has been an unfaltering source of support. She has endured with cheerful resignation my many absences when I have had to travel to distant particle accelerators. There are four grown children in our family, Ellena, Joel, Martin, and Sandra who pursue their activities in various parts of the country.

With regard to my non-vocational activities, in addition to getting much pleasure from various cultural activities, such as theater, music, ballet, etc., I enjoy painting and study Asian ceramics.

Autobiography: Henry W. Kendall

I was born on December 9, 1926 in Boston, Massachusetts. My parents were Henry P. Kendall, a Boston businessman, and Evelyn Way Kendall, originally from Canada.

I lived in Boston until the early 1930s when the family - there were five, for by then I had a younger brother and a younger sister - moved to a small town outside Boston, where the three of us grew up and where I still live.

I went briefly to a local grade school but was held back by a reading disability which was cured after I was moved to a school some miles distant. From age 14 to 18, most of the period of World War II, I spent at Deerfield Academy, a college preparatory school. My academic work was poor for I was more interested in non-academic matters and was bored with school work. I had developed - or had been born with - an active curiosity and an intense interest in things mechanical, chemical and electrical and do not remember when I was not fascinated with them and devoted to their exploration. Father was a great encouragement in these projects except when they involved hazards, such as the point, at about age 11, when I embarked on the culture of pathogenic bacteria. He also instilled in both me and my brother a love and respect for the outdoors, especially the mountains and the sea.

I entered the US Merchant Marine Academy in the summer of 1945. I was there, in basic training, when the first atom bombs were exploded over Japan. I was unaware of the human side of these events and only recall a feeling that some of the last secrets of nature had been penetrated and that little would be left to explore. I spent the winter of 1945-46 on a troop transport on the North Atlantic (a most interesting experience), returning to the Academy for advanced training in the spring of 1946. I resigned in October, 1946, to start as a freshman at Amherst College. Although a mathematics major at college, my interest in physics was great and I did undergraduate research and a thesis in that field. But history, English and biology were all most attractive and there was a period, early on, when any one of these might have ended up as the major subject. Non-college enterprises, in the summers particularly, absorbed considerable time. I and a Deerfield friend became interested in diving and two summers were spent in organizing and running a small diving and salvage operation. We wrote our first books after that; one on shallow water diving, another on underwater photography, with a considerable success for both. These activities, mostly self-taught, were a good introduction to two skills very helpful in later experimental work: seeing projects through to successful conclusions and doing them safely.

On the urging of Karl Compton, a family friend and then President of MIT, I applied for, and was accepted at that institution's school of physics in 1950. The years at graduate school were a continuing delight - the first sustained immersion in science at a full professional level. My thesis, carried out under the supervision of Martin Deutsch, was an attempt to measure the Lamb shift in positronium, a transient atom discovered by Deutsch a few years before. The attempt was unsuccessful but it served as a very interesting introduction to electromagnetic interactions and the power of the underlying theory.

The two years after receiving the PhD degree were spent as a National Science Foundation Postdoctoral Fellow at MIT and at Brookhaven National Laboratory, followed by a trip west to join the research group of Robert Hofstadter and the faculty of the Stanford University physics department. Hofstadter was engaged in the study of the proton and neutron structure that was later to bring him the Nobel Prize, work that even at the time was clearly of the greatest interest and importance. The principal facility used in this research was a 300 ft. linear electron accelerator, a precursor to the 2 mile machine at the Stanford Linear Accelerator Center (SLAC), later built in the hills behind the University. Here I met and worked with Jerome Friedman, got to know Richard Taylor, then a graduate student in another group and W.K.H. Panofsky, the driving force behind SLAC. Friedman, Taylor and I were later to join in the long series of measurements on deep inelastic scattering at SLAC.

As in the college years, absorbing non-physics matters claimed a portion of my leisure time: mountaineering and mountain photography. Stanford and the San Francisco Bay area offered a number of skilled climbs as well as Yosemite Valley not far away. After two years of rock and mountain climbing, I was invited on the first-of several expeditions to the Andes. Later there have been trips to the Himalayas and the Arctic, with cameras of increasing size to capture some of the astonishing beauty of those remote places. Many of the friends made during those years have remained through life.

After five years at Stanford I moved back to MIT as a member of the faculty. Friedman had gone there a year earlier and we reestablished our collaboration. By 1964, the joint work with Taylor, by then a research group leader at SLAC, was initiated. This collaboration was surely the most enjoyable of any physics I have ever done. It was a pleasure shared by most people in the effort and well recognized at the time. All three of us have remained, up to the present, in the universities we were at then. I have been involved in research in later years, after the SLAC effort wound down in the middle 1970s, at the proton accelerator at Fermilab and since 1981, again at SLAC. The most interesting physics for me has always been the searches for new phenomena or new effects. With colleagues I have searched for limits to quantum electrodynamics, heavy electrons, parity breakdown in electron properties, and other such things. Unfortunately, the ever-growing size, scale, and duration of particle experiments, as well as the much larger collaborations, have made such programs less and less congenial to me over the years, circumstances that disturb many in the physics community.

At the start of the 1960s, troubled by the massive build-up of the superpower's nuclear arsenals, I joined a group of academic scientists advising the U.S. Defense Department. The opportunity to observe the operation of the Defense establishment from the "inside," both in the nuclear weapons area and in the counterinsurgency activities that later expanded to be the U.S. military involvement in South East Asia proved a valuable experience, helpful in later activities in the public domain. It was clear that changing unwise Government policies from inside, especially those the Government is deeply attached to, involves severe, often insurmountable, problems.

In 1969, I was one of a group founding the Union of Concerned Scientists (UCS), and have played a substantial role in its activities in the years hence. UCS is a public interest group, supported by funds raised from the general public, that presses for control of technologies which may be harmful or dangerous. The organization has had an important national role in the controversies over nuclear reactor safety, the wisdom of the US Strategic Defense Initiative, the B2 (Stealth) bomber, and the challenge posed by fossil fuel burning and possible greenhouse warming of the atmosphere, among others. I have been Chairman of the organization since 1974. The activities of the organization are part of a slowly growing interest among scientists to take more responsibility for helping society control the exceedingly powerful technologies that scientific research has spawned. It is hard to conclude that scientists are in the main responsible for the damage and risks that are now so apparent in such areas as environmental matters and nuclear armaments; these have been largely the consequence of governmental and industrial imperatives, both here and abroad. Yet it seems clear that without scientists' participation in the public debates, the chances of great injury to all humanity is much enhanced. In my view, the scientific community has not participated in this effort at a level commensurate with the need, nor with the special responsibilities that scientists ineluctably have in this area.

This expenditure of effort and the sense of responsibility to help achieve control of aberrant technologies which drives it, stems in no small measure from the example set by my Father, who, throughout his life, spent a great deal of time and no small amount of energy on quiet, pro bono work. He was not alone among his own friends - nor among his own contemporaries - in this; it has been a tradition in New England of very long standing. In continuing to pursue such objectives, my expectation is that the challenges facing both me and the Union will be made substantially easier by the award of the Nobel Prize. This is perhaps the most attractive part of having gained this exceptional honor.

Autobiography: Richard E. Taylor

Medicine Hat is a small town in Southwestern Alberta founded just over 100 years ago in a valley where the Canadian Pacific Railway crossed the South Saskatchewan River. I was born there on November 2, 1929 and raised in comfortable if somewhat Spartan circumstances. My father was the son of a Northern Irish carpenter and his Scottish wife who homesteaded on the Canadian prairies; my mother was an American, the daughter of Norwegian immigrants to the northern United States who moved to a farm in Alberta shortly after the first World War. During my early years our family of three was part of a large family clan headed by my Scottish grandmother. I attended schools named after English Generals and Royalty - Kitchener, Connaught, Alexandra.

Although I read quite a bit and found mathematics easy, I was not an outstanding student. In high school I did reasonably well in mathematics and science thanks to some talented and dedicated teachers.

I was nearly ten years old when World War II began. That conflict had a great effect on our town, and on me. In rapid succession the town found itself host to an R.A.F. flight training school, a prisoner of war camp and a military research establishment. The wartime glamor of the military, the sudden infusion of groups of sophisticated and highly-educated people, and new cultural opportunities (the first live symphonic music I ever heard was played by German prisoners of war) all transformed our town and widened the horizons of the young people there. I developed an interest in explosives and blew three fingers off my left hand just before hostilities ended in Europe. The atomic bomb that ended the war later that summer made me intensely aware of physicists and physics.

Higher education was highly prized in the society of a small prairie town and I was expected to continue on to university. After some difficulties over low grades in some high school subjects, I was admitted to the University of Alberta in Edmonton. I registered in a special program emphasizing mathematics and physics and gradually became interested in experimental physics, continuing my studies towards a Masters degree at the same institution. My thesis research was a rather primitive effort to measure double b-decay in an aging Wilson cloud chamber. Between sessions at the University, I spent two summers as a research assistant at the Defense Research Board installation near Medicine Hat working with Dr. E.J. Wiggins, who encouraged me to continue my studies either in eastern Canada or in the United States.

Those were interesting years, and during this time I met, courted and married Rita Bonneau - a partnership which has enriched my life in every way. Together we decided to try California, and I was accepted into the graduate program at Stanford, while she found work teaching in a military school in order to support us both. The first two years at Stanford were exciting beyond description - the Physics Department at Stanford included Felix Bloch, Leonard Schiff, Willis Lamb, Robert Hofstadter, and W.K.H. (Pief) Panofsky who had just arrived from Berkeley. I found that I had to work hard to keep up with my fellow students, but learning physics was great fun in those surroundings. At the end of the second year I joined the High Energy Physics Laboratory where the new linear accelerator was just beginning to do experiments. My thesis work was accomplished there under Prof. Robert F. Mozley, on a rather diffcult experiment producing polarized g-rays from the accelerator beam and then using those g-rays to study p-meson production.

In 1958 I was invited to join a group of physicists at the École Normale Supérieure in Paris who were planning experiments at an accelerator (similar to the linac at Stanford) which was under construction in Orsay. I stayed in France for about three years working on the experimental facilities for the accelerator, and then participated in some electron scattering experiments. My wife began a new career there as a librarian at the Orsay laboratory, a career which was interrupted for a while when our son, Ted, was born in 1960. We returned to the United States in 1961 but a continuing connection to French physics and physicists has been a significant element in my life since that time - including a Doctorate (Honoris Causa) very kindly conferred upon me in 1980 by the Université de Paris-Sud.

Upon our return to the United States, I joined the staff of the Lawrence Berkeley Laboratory at the University of California. After less than a year in Berkeley, I moved back to Stanford where work on the construction of Stanford Linear Accelerator Center (SLAC) was just beginning. At SLAC, I started working on the design of the experimental areas for the new accelerator. By 1963 I had joined the group considering the requirements for electron scattering apparatus in the larger of two experimental areas. I worked closely with Pief Panofsky, and with collaborators from the California Institute of Technology and the Massachusetts Institute of Technology. I spent the next decade helping to build equipment and taking part in various electron scattering experiments, a number of which are the subject of the 1990 Nobel lectures. This was a period of intense activity, but also one of intense enjoyment for me. I was surrounded by people I liked and admired, and deeply involved in experiments which generated interest in laboratories and universities all over the world. I count myself extremely fortunate to have been at SLAC at that time.

I became a member of the SLAC faculty in 1968. In 1971, I was awarded a Guggenheim fellowship and spent an interesting sabbatical year at CERN, where I was impressed by the great progress that European science had made in the decade since I had worked in France.

Well before my trip to CERN, colleagues in the group at SLAC had become interested in testing some of the invariance properties of the electromagnetic interaction, a field which would absorb our efforts for most of the 1970s. When Charles Prescott joined the group in 1970, he began a serious study of ways to test parity conservation in the interaction between an electron and a nucleon. The electroweak theories of Weinberg and Salam predicted levels of nonconservation that looked extremely hard to measure. We attempted an experiment with the existing Yale polarized source, but the measurements did not reach the desired level of sensitivity. I was not very encouraging to my colleagues who wished to pursue the experiment to higher levels of accuracy. After the theoretical work of Veltman and van't Hooft and the discovery of neutral currents at CERN (during the year I was there) and at NAL (now Fermilab), the interest in experiments on parity conservation greatly intensified. In 1975 a new method for producing polarized electrons was discovered by a group in Colorado which included E.L. Garwin of SLAC. In 1978, after building a source for the linac based on the new method, we were able to demonstrate a violation of parity in close agreement with the electroweak predictions.

After the parity experiments, our group presented two proposals for large experimental facilities at PEP, the e⁺e^- collider then being built at SLAC. Both those proposals were rejected. The group was finally successful in proposing a relatively small PEP detector, but I did not take part in that experiment.

In 1981, I received an Alexander von Humboldt award which allowed me to spend most of the 1981-82 academic year at DESY in Hamburg. In 1982 I returned to SLAC as Associate Director for Research, a post I held until 1986 when I resigned to return to research. Since that time I have spent quite a bit of time in Europe and I am presently playing a very small role in the H₁ detector preparations at HERA.