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Oral History Transcript — Dr. H. William Koch

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Interview with Dr. H. William Koch
By Finn Aaserud

September 16, 1986

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H. William Koch; September 16, 1986

ABSTRACT: Youth and college education in Queens, New York; graduate studies and research work with Donald Kerst at the University of Illinois, 1941; Pd.D. in nuclear fission, 1944. Contract work during World War II for NDRC, Woolwich Arsenal in England; subcontract work on photo fission threshold for the Manhattan Project (Enrico Fermi); involvement in medical betatron work (Philip Morrison). Postwar transitions at the University of Illinois. Work at National Bureau of Standards as Director for the Betatron Laboratory and, from 1962, as Director of the Radiation Physics Division after Lauriston Taylorís retirement. Work on radiation processing and food rpeservation. Directorship of Standards; his goal for AIP, its independence. Discussion of the scientific information explosions and the National Science Foundation (NSF) grant (Elmer Hutchisson) Manpower Statistics (the Bromley Report); long-range planning committees (Frederick Seitz); effects of Internal Revenue Service audit; 1977/78; classification of physics documents (Philip Morse, Thomas Lauritsen); information as a saleable commodity (Germany, England); electronic information systems (PINET and PIMAIL); translation of Russian journals. Also, major events in reorganization; move to Woodbury and that facilityís later expansion, computerization of publishing activities, relationship between governing boards and Member Societies. Attracting new societies, AIPís early (pioneer) ventures: Manpower Statistics, history and education programs, and public relations. Series ends with a brief discussion of the career of Marshak Cleveland: his work in radiation treatment, founding his own company (Radiation Dynamics), and his new venture in Colorado. Also prominently mentioned are: Alan Astin, Edward U. Condon, Michael Danos, Ugo Fano, Evans Hayward, Raymond Hayward, Wheeler Loomis, Harold Wyckoff; and the American Physical Society.

Transcript

Session I | Session II | Session III | Session IV | Session V | Session VI

Koch:

It's interesting, you know, to reflect back over one's life; you had suggested thinking about the part of my career from childhood up to the Bureau of Standards stage, and then we could at some other time take the other part. One doesn't normally, I don't think, think about his career too much in detail. However, it's been interesting for me, in the last few hours, to think about what are the basic characteristics of my own career. One of the basic characteristics is that there's been great stability in it and in the few number of jobs that I've had. In fact the consistency of the work that I've done is striking. In every job that I've done — there haven't been many changes in assignments — I've always been in charge of the group. I started out with my PhD at Illinois, and I had charge of a small group doing research with cloud chambers there. Then in my next career step at the Bureau of Standards. I was there in charge of a group that started with two people and ended up with 120 people. Then I left there to come here to AIP. So I really only have had three careers. Also, in the last few hours, when I thought about what happened before those careers — thinking about my own childhood — the thing that strikes me here is also the stability and consistency. I had a father and mother who came from Germany. Let's talk about them a little bit more in detail and about my childhood, and then talk about the careers. My father and mother were both from Germany. My father had been in the German Army. He was born in 1887, and he then came over to the United States in about 1907 and went out to Minnesota, and was what was called a homesteader. He was given property to farm and then developed this farm into quite a farm, and in the process of doing that, he learned everything! He knew how to fix machinery, he knew how to do farming, and was, generally, a jack of all trades. He volunteered for the US Army when the US got into the First World War, and was then sent over to Germany, first to France, of course, then to Germany. Because of his background and knowledge of German and French, he became a translator for the US Army overseas. He would go in as an advance guard into a town and arrange for food supplies and so on for the troops. Well, in that process in Germany, he met my mother, who was a very young girl; she was born in 1900. After the war, he went back and smuggled her out of Germany. There's quite a story there but no need to tell that here. They got back to the United States, but because he had had a home way out in Minnesota which was so far away, my mother refused to go that distance and insisted on staying in New York. Therefore, my father set up an ice cream store business on Amsterdam Avenue in Manhattan and that's where I was born — in Manhattan — in 1920. I think of myself as one of the very few Manhattaners that has come back to Manhattan once they left. He worked hard in that ice cream store, and then gave it to my mother's brother, who took it over and promptly let it run down. My father in the meantime moved his family out to Flushing and became a salesman for the products that are used in an ice cream store — the extracts, vanilla and so on. So he then toured around, in a territory within two hundred miles of New York City. And that is how it was that I grew up in Flushing, Long Island. I had no brothers and only one sister who is seven years younger than I am. She was born just about the time that we moved out to Flushing. But because of the large time span between my sister and myself, I was almost like an only child. I was encouraged by my father and mother, who of course had to work very hard in coming to a new country. They really worked extremely hard, and of course, gave all kinds of love to this son, who was the apple of their eye. I have heard stories about how the nurse who took care of me would have to take me often to the ice cream store, and I would then always get ice cream. I have a love of ice cream as a result. But then when we moved to Long Island, and because of the seven years difference between me and my sister, I was left by myself much of the time. Fortunately, I enjoyed study. I was a good student in school. I did a lot of reading.

Aaserud:

What was your parents' educational background?

Koch:

Well, not much. My father and mother, I would say, went just through elementary school. No high school, no college. Partly because his mother had had a very unhappy marriage. I guess the first man that she married was a drunkard, and somehow got killed in a barroom brawl. She remarried and therefore my father had had a number of stepsisters and stepbrothers, and then when he came over here —

Aaserud:

How old was he then?

Koch:

When he came over here, he must have been about 20 years old. He was born in 1887. I would say 1907, that's when he came over, and he went out to Minnesota, developed quite a good livelihood there, and because of that — when he was married and lived in New York — he then paid for his stepbrothers and stepsisters to come over here. So, like typical immigrants, in the process, you see, he put all of his work and all of his money, all of his resources that way. But because they had had very little education, they of course encouraged me as much as possible to obtain the formal education that they lacked. And living in Flushing, I went through Flushing High School. I had, because I was a good student, skipped grades in school. They did that in those days. I skipped two years of elementary school; so when I was 16, I guess, I graduated from high school, went one semester to City College, commuted into the city, and dreaded that. Then Queens College opened up across the highway from where we lived; so I was able, in this new school, to walk to school, and because it was a free city school, and because it was a new school, I was in the first class of only 400 students with 400 being added each semester. I was also in the first graduating class. Queens College was deliberately set up as a teaching institution. The teachers that they had there — it was not too long after the Great Depression, so they had the pick of the crop of teachers — were really excellent. And because it was such a small class, and because it was a new school, they worked very hard in trying to teach excellent courses in physics and mathematics. Those were the two subjects that I enjoyed, and I could have majored in either one. I had enjoyed mathematics because when I was in high school, I was on a math team that would go to different high schools competing. And also, when I was in college, I had an excellent math teacher, Arthur Sard, whose brother incidentally is a prominent elementary particle theorist. But Arthur Sard was an inspiring mathematician who used to be an actuary for an insurance company, and that's where I thought I would end up. I also had Banesh Hoffman, now a well-known author of a book about Einstein, as another college mathematics teacher. But the college physics courses were also excellent, and I didn't really know what I wanted to do. When I graduated from college, another graduate, Ferd Shore, and I decided almost as a lark to apply to graduate schools and see if we could get any offers. I got an offer from the University of Illinois. It paid a thousand dollars a year, and it was just such a stupendous offer that I told Ferd Shore that I thought I'd take it for a year and see if I liked it. So I took it, with that in mind, and went out to Illinois. I didn't realize what a tremendous department was being developed there. In fact, Dave Lazarus, who's the editor-in-chief of Physical Review, is a professor at Illinois. He joined the Illinois faculty a few days before I left to go to the Bureau of Standards; so he's been there quite some time. He told me last week at the AIP executive committee meeting that he has just about completed a history of the early days of the physics department. He has told me about the part that he has completed. In his going through the files and seeing how the department got established, you can now get a history of the department to learn why it became such an important department. Wheeler Loomis chaired the department there, and gathered, before the Second World War, an outstanding collection of physicists. Dave Lazarus said last week that one of the reasons possibly was that, at that time there was prejudice against Jews and Wheeler Loomis obviously had no such prejudice and was able to collect some outstanding people, some of whom might have been prevented from going elsewhere because of prejudice. Sid Dancoff, Phil Morrison, Robert Serber, Lee Haworth, John Manley, Don Kerst were all people that he had collected. Kerst came two years before I came. In fact, I wrote up a little recommendation for him to get the Robert Wilson Award. I'd like to leave it with you because it describes why I have such a high regard for Don Kerst, who was my thesis advisor. But let's get back to the story of my taking this assistantship at Illinois.

Aaserud:

If we could backtrack a little bit — when you went to high school or college, you weren't sure about whether mathematics or physics would be your field, but you were generally scientifically inclined.

Koch:

Oh yes.

Aaserud:

What kind of influence or what kind of things caused that? Is that something that came naturally, or was there some specific teacher, something in the home, some experience?

Koch:

Well, my father enjoyed mathematics, and he also was a tinkerer. Because of his life on the farm, he could repair anything. I have started reading the Feynman book, in which he described how he had fixed radios when he was a kid. Well, my father encouraged that too, to do everything in the house. We would, for example, typically repair radios. We would do housework, paint, we'd paint the house every two years. That's what my father had me do. I said I graduated very early from high school, at 16. And because I was slightly built, when I was very young — I was two years younger than most of the other kids in my class — I did not really pal around with the other kids very much, so I read. I enjoyed being on this mathematics team, in high school. But I don't know what other things, other than my father's interest in mathematics and whatever he could pick up — self-taught, in science — that influenced me.

Aaserud:

That seems to be a very general trait for the backgrounds of American physicists anyway, that tinkering approach.

Koch:

Yes.

Aaserud:

I think it contrasts with the European scene in some sense, which had a more theoretical inclination from the outset, but that's another matter. So there was no specific person or teacher or fellow student?

Koch:

Well, one of the peculiar things about me, strange thing about me is that I have very little memory going back in time. I always kid my wife that I can go to a movie and I can come out of a movie and I wipe my memory clean. I don't want to be cluttered with that stuff. And so I forget quickly about a movie. She can remember all the details of a movie. But she then kids me that I know every detail of, calculations and things that I've done over the years. So those things have stuck in my mind, but I don't remember trivial details. I don't remember the elementary school other than one particular experience — a trip to Germany. I must have been eight years old — right after my sister was born, my mother took my sister and me over to Germany to visit her parents. I was put into a German elementary school. I went to school for three months while we lived there, and I learned German so thoroughly that I forgot English. So when I came back to the United States, I could not speak to the kids on the block. I couldn't converse with them. The thing I remember — that's about the only thing I do remember about elementary school, after returning to the U.S. from Germany, was that I went into the basement of a next door neighbor who could speak German — we had then a coal stoked heating system, and we would then have shovels for removing ashes from the coal stove in the basement — the neighbor was in there taking the ashes and putting them in cans — that was typical of what we did then. I spoke German to him, and he spoke German to me — and what a thrill that was! We would get monthly report cards in elementary school, and the first month after the return from Germany I did terribly. I got Ds in many subjects. But then the next month after that I got A's again. I obviously learned my English again, and quickly.

Aaserud:

Then you forgot your German?

Koch:

I pretty much have forgotten German. Apparently my accent is reasonably good. When I'm in Germany for a while, I then start picking it up and use German. But I'm not fluent in German. I can usually understand what Germans say but not if they speak too rapidly. So, if we may, let's go then to graduate school. My first six months was as a teaching assistant teaching elementary physics. I had started in September 1941. In about December, Don Kerst came back from the General Electric Company where he had built a 20 million electron volt betatron. He came back, and wanted some help to install the machine in the power plant of the University of Illinois, because they had made room for him there. Four of us volunteered. I didn't know the difference between a cyclotron and a betatron, but I asked enough of the staff members and students, and it sounded like the betatron concept was a new interesting concept. I started work with Kerst, and that of course established the rest of my life, career-wise. [Dr. Koch has requested that the following passage "A" be moved here from the 16 September 1986 session in order to retain the chronology of events]

Aaserud:

We are back in H. William Koch's office at the AIP headquarters, on the 13th of October, 1986. We'll start by backtracking a little bit. You found this letter from Kerst to his staff at Illinois, dated the 24th of November, 1941, and it was just after you came to Illinois.

Koch:

I started in September of 1941 as a young graduate student. I had been teaching elementary physics as a teaching assistant, and it was in December that Kerst came back. Then four of us started working with him, and this letter was written in anticipation of his coming back. He was still at the General Electric Company. As you'll note from the last line of the letter, he had not yet named this new machine.

Aaserud:

"I'm still looking for a good name," he wrote.

Koch:

One of the first things he did when he came back was to see if we couldn't assist him in providing a new name. One of the names that seemed to be very popular for a while was Rheotron — that's a machine for providing flux flow. But that seemed a little bit contrived, and it ended up then being a lot simpler name, the Betatron. But in this letter, he tried to envision the various kinds of experiments that could be done with the Betatron, and as soon as the machine got running, we tried every one of them, just to see what would happen. We put something in the beam and see if you got an effect.

Aaserud:

Even before he returned?

Koch:

No, the machine parts came and he came back with it. He didn't want to stay at Schenectady anymore. He was upset by the people at Schenectady. He felt that they had not lived up to their agreement to build him a much larger machine, and he settled for the 20 MEV machine. As soon as it was done, he came back with it.

Aaserud:

The fact that he addresses his letter to the four of you, does that mean that you were formally working under him?

Koch:

Oh yes. Lyle Phillips was the only one who was the staff member there, so he was the senior person in the group that joined Kerst, but then there were also Gail Adams, Bob Clark and myself, who were the research assistants. George Baldwin worked for Kerst while Kerst was at GE and continued after he returned only long enough to obtain his Ph.D. Bob Clark had difficulties. I don't know whether he ever did get his Ph.D., but he tried his examinations time and time again to see if he could pass them. There was just something about Bob Clark that didn't permit him to pass the examinations. So he did not continue on, and in fact he was then replaced, after the war, by Clark Robinson. That left Clark Robinson and Gail Adams and I. Lyle Phillips, in fact, dropped off, and then there were some others who subsequently joined us as bigger and bigger machines got running, and made possible better and better research.

Aaserud:

Just a small question. It says at the end of paragraph two here, "In this way neighboring masses can be determined from some mass which Jordan may be able to supply to us." Who was Jordan?

Koch:

Ed Jordan was a staff member at Illinois who was a very famous mass spectroscopist. He had developed many fine large DC magnets that could be used for separating masses. He was quite well known. In fact, he was also one of those super lecturers. I had him for electricity and magnetism, and he was a very painstaking teacher. In fact, Jordan had been a graduate student of Bainbridge at Harvard, and Jordan-Bainbridge magnets and mass spectrometers at the time were very famous.

Aaserud:

It's good just to have him identified. It's a very neat combination here of the physical side of it and the medical side of it. The numbered parts of the letter are physical and then Kerst adds that also the medical people will have use for this.

Koch:

Oh yes. Then of course, it got to be a very good medical tool, so good that Allis Chalmers Company in Milwaukee, Wisconsin, manufactured betatrons, and one of the graduate students, a man by the name of Dane Skagg, went to work for Allis Chalmers to build these machines and market them to hospitals. The Sloan-Kettering Cancer Research Hospital here in New York City, and the Michael Reese Hospital in Chicago were two hospitals that had Allis Chalmers betatrons.

Aaserud:

How soon after was that?

Koch:

Well, it must have been in the late forties that they got into the manufacturing of them. They sold them also of course for industrial radiography, for example to the Watertown Arsenal in New York State, which had a betatron program in industrial radiography for investigating the shadow pictures of large slabs of steel.

Aaserud:

To what extent were you involved in that kind of transfer?

Koch:

Well, we all got involved in all the different programs. There were not many of us, and it was a really exciting period.

Aaserud:

Kerst has a hand written PS to the letter telling you to talk to Professor Serber if there are any questions, so Serber was also closely into this.

Koch:

Oh yes. I think I mentioned earlier that Kerst was a student of Ray Herb, a Van de Graaff expert at the University of Wisconsin. Kerst had gotten his PhD under Herb, and then it was after that that he worked for the GE Company in Chicago, in the X-ray department. Then he was able to make a 2.3 million volt betatron work. That was before, I believe, he came to the University of Illinois. That immediately brought him into prominence, and he was recognized by Wheeler Loomis as potentially someone who would go far. So Wheeler Loomis hired him, and Serber, as you saw from that scrapbook picture, was one of the people that Illinois had been able to hire — Wheeler Loomis had hired him — and Serber and Kerst then developed the theoretical aspects of betatrons. The whole question of space charge limitation, for example, to the magnitude of the electron beam current that you could contain, in the betatron. That was one of the calculations that Serber had helped with.

Aaserud:

Serber was instrumental in making the betatron work in practice?

Koch:

Well, Kerst had taken what Wideroe had originally developed in Germany — Wideroe never got a machine working before that. Kerst was careful of things like space charges and where space charges would build up on the inside of the doughnut shaped vacuum tube. Kerst was very sensitive to this. He thought very much like an electron, and he would think, "What kinds of things would influence me if I were an electron floating around in there?" He was really very clever, and was good theoretically and experimentally as well. In some respects it was a difficult field because — I think I said this earlier — up until about that time, one always worked with positive ions that did not get very relativistic. Betatrons were the first machines to really get into the relativistic region. They had to worry about whether the theory was right, and that's where Serber was very helpful. [End of Passage "A"]

Aaserud:

So you pretty quickly decided that physics was your thing.

Koch:

Oh yes. It was exciting and everything that we did was new. You have to remember the time period that was involved here, because it was the start of the forties, before the Second World War started. What had happened in physics in the 1930s was that people had made Van de Graaffs and cyclotrons for positive ions, but they had really not gotten up to very high energies. People were interested in how to get higher and higher, and Kerst came along, having studied Wideroe's work. He did the theory and then he made a small 2.3 MEV betatron before he came to Illinois. It was this large. That was one of the first machines I worked on, before the 20 MEV. I had the job of further developing the 2.3 million volt betatron, working on silver coatings on the inside of doughnuts — things like that. Then we manufactured the 4.5 MEV betatron. In the meantime, we assembled the 20 MEV betatron that Kerst had brought back.

Aaserud:

Backtracking a little bit again, how prepared if at all did you feel for starting in physics when you came to Illinois? How had the college education prepared you for that?

Koch:

It prepared me very well. As a result, I did well in my various Illinois graduate courses. My first course in graduate school — I remember this very well — was Bruce Lindsay's Mechanics. That's an excellent book, and I practically memorized that book. And I enjoyed the way Lindsay had presented it. It was a thrill — in recent years — to have met him. And then I had Sid Dancoff who was a former Oppenheimer student, and Nordsieck, who was at Illinois, and Serber — Serber and Dancoff were just super teachers. A terrible teacher was James Bartlett, who was so egocentric that he would come into class and say, "NOW, what shall we talk about today?" He would then proceed to give an impromptu, poorly-delivered lecture. In contrast you had Morrison, Serber, Dancoff, who also taught at Illinois. I kept log books and what I did was to take rough notes during the day in class, and each evening I would transcribe them into these log books. I still have them at home. Those were my textbooks, and I discussed them then with the other graduate students. I worked all the time, you know, Saturdays and Sundays, until late each evening. I enjoyed studying. I had learned how to study, so that came easy to me. And so when we worked with Kerst, Kerst was a workaholic. He worked all the time. We would once in a while have some social things. One weekend, since he was a ski enthusiast, from University of Wisconsin he said, "Why don't we go and ski up in Wisconsin?" That was about 300 miles away. So we continued to do experiments up until 6 or 7 o'clock, Friday night. Then we hopped into his two door Plymouth sedan. He had skis and sleeping bags and things like that on the luggage rack of his car roof, and we drove up to Wisconsin. I should say that he drove. He seemed to have inexhaustible energy. The rest of us slept. He drove all during the night, and we finally got up to Wisconsin. If you do 50 miles an hour, 300 miles would be six hours. So we must have arrived there early morning, and frankly we were all dog tired. We had planned to sleep in sleeping bags, which we did, but when we got up there, we couldn't curl into sleeping bags, in the morning, and go to sleep. So we decided to go skiing, and then in the afternoon, we went to a movie because it was warm in the movie. We all went to sleep in the movie. Then when it got to be dusk, and we pitched tents, in the snow, we slept in our sleeping bags that night. The next day, Sunday, we went for more skiing, and then early afternoon took off for Illinois again. That was quite a social event for us all. The Illinois department was a very friendly place. It was relatively small at the time. In fact, that's the thing that Lazarus remarked to me, again, what a family affair the whole Wheeler Loomis enterprise was, and that's the history that would be interesting for you to get. How in the middle of nowhere he could have built up such a remarkable department. It really has always been an amazing place, all because of Wheeler Loomis. So, getting back to my involvement, I started in that fall of the year, which must have been the fall of 1941, because in December, war was declared. Being in a class where we learned experimental techniques and did glass blowing, I remember having a vacuum system with these glass tubings and having a crack develop, and having the crack go all the way around, and my trying to chase it. And about that same time, I heard about war being declared. I continued in graduate school all during the war. Kerst had, through the Office of Naval Research — or rather its forerunner, the NDRC, (the National Defense Research Council) — a contract to develop this fascinating new machine that —  could produce high energy Xrays in fair quantities, that could be used for radiographing thick slabs of steel. So the military got interested in that. We also had a contract with Woolwich Arsenal in London. That contract was such that it paid for the development of glass tubes that were sealed off and used as the donutshaped accelerating tubes. We had this contract with Woolwich Arsenal, and it was a question of whether we could seal off these tubes. That was the first major development on this 2.3 million volt betatron  to make a sealed off doughnut. If we could make a sealed off doughnut, Woolwich Arsenal wanted to have us make a 4.5 million volt betatron. That was the biggest machine at the time that we could conceive of that could be porta ble. Because it was for England, it had to operate at 50 cycles, not 60 cycles. We made it so that you could operate on a 50 cycle power supply, and the electrical engineering department at Illinois had such a generator. We made the betatron so that it was dunked in oil, just like a regular transformer, and we were successful in operating it with the sealed off tube. Now, that was the rationale for my not being drafted into the military. While I worked on that project, I worked on my thesis. In the meantime, Kerst had gone to Los Alamos. He was developing the betatron, because of the bursts of radiation, as a trigger for a bomb and also as a device to study the characteristics of imploding bomb components.

Aaserud:

Yes. That was in 1943, when he went, right?

Koch:

Right. And I got my degree in 1944, so I was left pretty much to my own resources to figure out what kind of research to do for a thesis, and George Baldwin was one of the other members of this four student group that helped Kerst.

Aaserud:

Who were the others? There was Baldwin, you and ?

Koch:

Baldwin, Bob Clark, and Gail Adams were the other three students and Lyle Phillips was the faculty member. Eventually Clark Robinson came after the war. And George was the first one to do thesis research with the betatron. I worked along with him, and we did the first photonuclear experiments. And you have to again appreciate the era, because no one had ever been able to get high energy X-rays in quantities that could be used for exciting nuclei by producing gamma-n and gamma-p reactions. All the work before that had been done with neutrons generated by p-n reactions on a Van de Graaff or cyclotron, and it was all positive ion research. We were really blazing new ground. So George for his thesis did a lot of experiments where we looked for thresholds. We had the periodic chart and we would take a material, and bombard it in the betatron. Oh boy, we got a radioactivity and we would try to find out what the half-life was and what the radiation was, Then George said, didn't I want to take some of the elements and split them off? I could get my thesis on one set, and he would get it for the other. I said, no, he should use that as his thesis and I would do something else, being independent. I decided to take uranium and thorium, and do photo fission. I made my own little ion chamber, coated the plates with the uranium oxide and thorium oxide, and then looked for fission pulses on the oscilloscope — and boy, those fission pulses were huge! I took that, with a simple amplifier, put it into an oscilloscope, and we would slowly increase the energy of the betatron, and you'd see big blips occurring, massive. It was exciting.

Aaserud:

You had no problem obtaining uranium at the time?

Koch:

No. These were ordinary chemicals in the chemistry lab. Then I got my degree in 1944, and it must have been right after that that I went to England. I don't really recall it; it was in March of the year. I think it must have been right after I got my PhD in February of 1944, so I was quite young then. See, I had gone to Illinois when I was 20, four years after graduating from high school. My birthday was the end of September, so I must have been just going on 21, and then I got my degree in February so that was three years later, so I was 24.

Aaserud:

That's quick.

Koch:

And I took this betatron to England. I couldn't figure out what those people were doing that I delivered this to. They were bomb disposal people that had to inspect duds, and they would defuse them. What they wanted this betatron for was to have a portable unit that could be used to irradiate the dud and get an x-ray picture, so they could figure out how to defuse the thing. Well, I came there and I could not figure out what these people were doing, and no one would tell me, and I only realized a few weeks later. I was there for a month and got the machine running, but then I realized that they had been working all night and every night. They would come in in the morning dead tired, and I'd try to get them to work with me so I could get out of there. It was the time that the V-2 bombs were just coming over from Germany, and the first night I was there, in fact, I was told, "Look, there are bombers coming over, come downstairs beneath the basement steps." I said, "No, I'm going to stay here." And I went to sleep. Well, pretty soon the windows were blown out of my bedroom. After that I had no problem about going beneath the basement steps. The four of us, four Americans, had come on different missions. We had this Scottish housekeeper that kept house for us, so I would then commute from Wimbledon to Woolwich Arsenal, install the machine, and then got out of there. It was not too long after that Goward and Barnes converted my betatron into the world's first electron synchrotron. So it was a reasonably simple process to do. We should have done that at Illinois.

Aaserud:

So did the Woolwich arsenal people make good use of the betatron?

Koch:

No, I think they felt it was just too much trouble. They used radium sources and also just counted on their dumb luck to defuse the bombs.

Aaserud:

But that was the contract.

Koch:

Yes. Then after I came back, I was invited to come up to the Met Lab up at University of Chicago, Metallurgical Lab, and Sid Dancoff, who I had taken quantum electron dynamics from, called me one day and invited me to come up and give a lecture about my thesis work. So I went up, and the people that were in the audience were Fermi, Wigner, Seaborg, Morrison, Dancoff. After I gave my talk, Fermi said would I come with him. He always carried a slide rule with him. He said, "How did you paint your sample onto the plate?" So I told him. He said, "How thick was it?" Well, he made some estimates, using his slide rule, and he said, "Well, I think you can do it." I said, "What?" He said, "We would like you to do some experiments for us. You go over to see Glenn Seaborg, and Seaborg will describe to you how we will manufacture samples for you, and you take them down and run them on your machine." So then Seaborg gave me indoctrination about how to handle neptunium plates and plutonium plates, very powerful alpha emitters. Then they made separated isotopes for me, uranium 233, 235, 238. They asked me to determine the thresholds of these, and the thresholds were all about 4.9, 5 million volts, so our 20 MEV betatron was ideal for this, and the sensitivity was really quite good in my setup.

Aaserud:

You did that at Illinois?

Koch:

Yes. So then they told me that I would always have to have a guard with the samples. Wherever the samples were, there would be a guard. So I had my own project then. They gave me a car, and a secretary. I had one man who helped me and eventually two men. John McElhinney and Ed Gasteiger were two graduate students that I employed on my project. The remarkable thing was that all of our experimental photo fission thresholds were within .2 of an MEV of one another, and if you take the Bohr-Wheeler theory the predictions were that you'd get a spread of about a million volts. So a lot of time was spent to make sure that there wasn't something about my equipment that was misleading us. But it was really quite clear, after we did more and more experiments, that these were real results, and they then, apparently in the process of just trying to understand how a bomb works, took that information to see when gamma rays in a bomb would set off fission. So that was part of my thesis. [Dr. Koch has requested that the following passage "B" be moved here from the 10 March 1987 session in order to retain the chronology of events]

Aaserud:

We're going to conclude the interview with Dr. H. William Koch today — or we hope to anyway.

Koch:

We'll make some comments about the way some of this earlier career is fitting into what I had hope would be a new career for me, after I left Illinois here.

Aaserud:

Good.

Koch:

The first is this telegram that I received when I was at the University of Illinois. Even though the telegram is not dated, it must have occurred in the late 1944 to early 1945 period. I say that because it sounds like it was sent just at the termination, or certainly in the process, of our subcontract with the Metallurgical Laboratories. It's informing us that we're not supposed to divulge the details of the research, so let's talk a little bit about that contract. The work that I had done for my thesis was the threshold for photo-fission in uranium and thorium. The surprising thing that came from that threshold work was that the thresholds for uranium and thorium were very similar to one another. And one might say that was a defect in the experimental arrangement, that you always got the same answer. But the betatron was really an ideal tool for this, where you could take an ionization chamber with the fissionable material. It was simply a powder that I coated onto the plates of an ionization chamber and stuck into the betatron beam. When you started getting fission, you got tremendously large ionization pulses. I had built this equipment myself and I was very pleased at how dramatic it was. You would just inch up with the betatron energy — that was extremely controllable — and then all of a sudden you'd see these tremendously large pulses. You would continue to follow that on up, and you would get the number of pulses increasing in number, as you increased the betatron energy. Well, uranium and thorium showed the same threshold, and this was puzzling to people that were designing atomic bombs at the Metallurgical Laboratory and down at Los Alamos. They wanted more research done on it. So Sid Dancoff, who had been my instructor in quantum electrodynamics while he was teaching at Illinois, invited me to go to the Metallurgical Laboratory of the University of Chicago. I went up and was then asked to describe my research in a seminar. I was very young, obviously, then, and was just awed by the audience that I had, because there was Eugene Wigner, there was of course Sid Dancoff, there was Phil Morrison, there was Enrico Fermi, there was Glenn Seaborg, and, of course, AIP's friend, John Wheeler. All the names of well-known people, clustered at this Metallurgical Laboratory. After my seminar, Fermi asked me to go to his office with him. He had a little pocket slide rule, and he asked me to describe the sizes of the samples, and tell more of the details of the experiment to him — how I'd coated the samples on. He then made some very rough estimates, and he said, well, he thinks what he would like to propose is doable, and would I like to do more experiments? I said, "Oh yes, I'd like very much to do more experiments." And he said, "Well, we will supply you with samples, and they will be coated samples, and we will know very quantitatively the amount of material that's going to be put on there, and these will be separated isotopes." Well, I knew nothing about separated isotopes at the time, and he told me then how they made reference to it. "You take the atomic number, say 92, and you take the atomic weight, 238, and then you refer to that isotope as 28." He took the last digits in both numbers. He said, "We'd like to give you 25, 28, we'd like to give you 49." That was plutonium, as I remember it, and samples of neptunium. Some of them were highly alpha active, so I was then sent to Glenn Seaborg, who then asked me for the exact design of my chamber — how large would the plates have to be, etc. I gave him all that, and then he put me through a course on wearing coveralls and gas masks, and how to handle the samples, and how to transfer from the box that they were going to send them in to the other. We must have talked about this earlier, because I think I remember saying to you that they provided me with a guard, with a secretary, with an automobile. The guard would go wherever the samples would go, and the guard would always be reading comic books. He had nothing else to do but sit outside the door of the room that would contain these samples. We would variously have them either in our offices in the physics building, which was two miles or so from the betatron laboratory, and we would then transport them back and forth with this little panel truck that we had. The panel truck must have been a physics department one, because I remember the additional car which they provided me. But we did these experiments, and we found that even with the separated material, and the thresholds were clearly within a narrow range of 4.9, 5 million, 5.1 million volts — there was very little difference from one to the other. Kay Way did a lot of nuclear data table work at that time and for years after. Incidentally, she finally became a member of my division at the National Bureau of Standards. But at the time, Kay was connected with the Metallurgical Laboratory. While she was there, and also at the Bureau of Standards, she did interpretations of inverse reactions — in other words, sending in neutrons and getting out photons or getting out fissions. She had a way of interrelating the thresholds for neutron fission with our thresholds for photo fission. The Bohr-Wheeler model said that there should be something like .8 of a million volt differences in photo fission thresholds, and that would have been easily observable in our experiments. Kay Way concluded that they should be very close to one another; consistent with what we had found in our experiments. So there seemed to be a difference between our experiments and the Bohr-Wheeler theory at that time. How important these photo fission threshholds were in an understanding of how a bomb works, it's hard for me to say. It was certainly one of the additional pieces of information that they wanted to know, as they tried to understand the phenomenon of an exploding bomb. So that's the background here. Oh, the only other thing that I think I mentioned earlier was this telephone call; that was from the head of the Metallurgical Laboratory. He was at the time a quite well known astronomer who had, for the University of Chicago, assumed the role of the manager of the Metallurgical Laboratory. This man called me up, as he obviously was calling up various subcontractors, to tell them that the Italian navigator had landed, and he had found the natives very hospitable — a message like that for people who had been closer in on the classified work which I certainly was not. I had a very incidental role. But that was a mysterious message. [I learned later that it was intended to inform contractors that the first test firing of an atomic bomb at Alamogordo, New Mexico, was a success] It was after this contract was concluded, that I worked for six months at the Oak Ridge National Laboratory.

Aaserud:

But the telegram was before then. [End of Passage "B"] This [work on photo fission thresholds] was an extension of your thesis suggested by Fermi?

Koch:

Yes. And then the other part of the thesis had to do with depth dose distributions in water, using five, ten, fifteen, twenty MEV peak bremsstrahlung radiation to see how the depth doses would look. At the time Phil Morrison was interested in problems. Serber had worked with Kerst on betatron theory, so Morrison helped me with trying to understand the shape of bremsstrahlung spectra, which people really had very little feeling for. It was a continuum with the maximum energy determined by the kinetic energy of the electrons hitting the target. So in the betatron you accelerated to 15 million volts and you get this continuous spectrum with the peak. Well, Morrison tried to do some predictions of spectra that we would expect to see in our set-up, and it turned out that his calculations initially were wrong. I think he's always been embarrassed by the fact that they were initially wrong. He's such a good physicist, and they were at the time very difficult calculations. But then he also made some predictions of the kind of dose distributions we would expect to see. We used presswood sheets to simulate a body, and we would then take an ion chamber that I had made. We then paraded this through the depth — that's the way we made our measurements — and the radiation of those energies were sufficiently directional so that you would have the secondary products continue on pretty much along the same line as the primary radiation. So you could define a pencil of radiation within a body, and the peaks for 20 MEV X-rays were about 4 centimeters beneath the surface. So the directivity of the radiation and their secondary products, and then the fact that you got more of a dose within the body than at the surface, suggested that it would be a very nice means for cross-radiation. You could indeed burn out a cancerous spot within a patient. Well, it wasn't too long thereafter, I would say in about 1947, that a graduate student at Illinois developed a brain tumor and we had to put my experiments to a real test.

Aaserud:

Yes. I have that paper here.

Koch:

And it was such a pathetic case, because he had been operated on surgically — had portions of his brain taken out — and he had a big bulge on his head. So his wife, whom we all knew, requested us to see if we couldn't use this new machine on her husband, and so we all pitched in. It was really quite a team effort — Morrison, Dancoff, there was a young medical doctor, Henry Quastler, who was the leader of the medical team, and — Aaserud: There were 17 authors, I think.

Koch:

Yes, that's right. It was quite an effort. And so we just worked round the clock to figure out how to plan the treatment — how do we set this patient up? We made a model of his head, and then I made measurements throughout the head to see how the doses would be distributed, and we had of course x-rays of his head, and Quastler knew about the operation, so, again, there we were the first in that business. At dusk — we didn't let the word get around — as soon as it got dark, the ambulance would come from the hospital, bring the patient in, and we then would treat him over a two week period. Then we stopped, and started again, after he got radiation sick. And it wasn't too long thereafter that he died of pneumonia, and then his brain was sliced up and we could see the impact, the pictures are in the article. But it was quite an experience. So everything that we did, it was just a new field. Nothing that was done had been done before, and so, in that respect, everything came easy. You know, it was there to be done and we did it. So we did photonuclear, photo fission, we soon worked on giant resonances, and then tried to do comparisons with what had been done with Van de Graaffs and cyclotrons and so on. It was a very exciting period.

Aaserud:

And you immediately got involved in the larger implications of physics. First it was the war effort; secondly it was this medical connection.

Koch:

Yes.

Aaserud:

Generally speaking, how close was the relationship between the Illinois department, and the betatron in particular, and the medical side of it?

Koch:

Well, that was very close.

Aaserud:

Also funding-wise?

Koch:

Well, I don't know that the funding came from that. In fact, most of the funding for the Illinois project came from the state. You see, it was before ONR. ONR was established about 1949, I think. So the funding that came during the time right after the war and before ONR was established pretty much had to come from the state. The state funded Illinois for the development of this gigantic machine, you see, the 300 MEV machine. At the time it was a huge machine, and it was a 300 ton magnet. On this 300 ton magnet, Kerst did most of the design work, although we all did help him with the design work; this was a big transformer and it was built flat. We had 14/1000 of inch thick laminations, that we made the dies for and stamped out the laminated sheets right in the laboratory there. We collected it all, we did it all, and so we made this machine and wrapped the coils and then Kerst, who was a very clever guy, designed the measurements and we made the measurements and made the corrections for the magnetic field in the accelerating gap. You have to realize how unique it was, because all previous circular machines, cyclotrons, had DC magnets, where they were just chunks of steel, you know, big slabs of steel, and a permanent DC magnet. The betatron was an alternating Current magnet, so anything we stuck in the field could have eddy currents in it. In fact, that's where Wideroe failed. He didn't understand really the eddy currents that would be produced in the laminations, and what kind of fields the accelerating tube would produce on the electrons. Kerst had a great sensitivity for that, and with this big machine. We then made the doughnut for it, that was on pumps — it was not sealed off — and then eventually we removed the electron beam from the betatron.

Aaserud:

When was the big machine completed?

Koch:

That was completed four months after I came to the Bureau of Standards.

Aaserud:

Yes, of course.

Koch:

Because I started on September 19, 1949, at the Bureau of Standards, and I was invited back for a party in February of 1950. And there's one paper that I and others co-authored with Kerst, describing this 300 MEV betatron. That was a big development. So I was describing how we piled these laminations manually and clamped the thing. This was a big rig. And then we got a tractor and we poked a hole through the wall of this big room. The room must have been a 40 foot cube. And the tractor took this 300 ton magnet and set it upright. It was on rockers. It was designed to be that way. Then when it was upright, we clamped it in place and removed the rockers, and then that was our machine, and the doughnut was put in horizontally. So the magnet had to be made vertical. Because the state had supplied the money, and it was quite a bit of money — several million dollars, as I remember — to build a 300 MEV betatron, Kerst felt a tremendous commitment to the state to fulfill the job for which he got this money. He could see nothing else but to finish that job. He was committed to it. So I would say in about 1947 or so — I don't really remember, I should have looked up those dates — Lee Haworth and John Manley, with Kerst, proposed the development of the synchrotron. Haworth eventually became director of Brookhaven, and also director of the National Science Foundation and so on. Manley had been with Kerst in Los Alamos. Both of them were at Illinois, and thought that we really should interrupt the development of the betatron. Well, Kerst would have no part of that. He had committed himself to making the betatron. And he would have no part of making a synchrotron pie in the sky. We could do that later. By the time the 300 MEV betatron was running, Goward and Barnes had already done it in England with my 4.5 MEV betatron, and McMillan had built a synchrotron at Berkeley. And when you now read McMillan's account in Physics Today — McMillan is a typical and very aggressive typical Nobel Prize winner — he gives credit to few others and he gives very little credit to Kerst. But as far as I'm concerned, Kerst made all of this possible. And Kerst never really got enough credit. I think one of the reasons is that, as is typical of Nobel Prizes, the Nobel Prize Committee comes to a school of the Nobel Prize winners, and says, "Who do you recommend?" and so Nobel Prizes beget other Nobel Prizes. The Midwest had gotten no Nobel Prizes, so there was not too much support for Kerst. Many of us felt that he should have gotten a Nobel Prize.

Aaserud:

I would like to know a little bit about the war period at Illinois, and how the department was affected by that and how your work situation was affected by that. Well, when you came, the war had started already.

Koch:

It had just started.

Aaserud:

Had just started, yes, and of course that took its toll on the department.

Koch:

Oh, yes.

Aaserud:

I'm sure people started leaving almost immediately, correct?

Koch:

In fact, Ramsey came to Illinois, I think a few days before I came to Illinois as a graduate student, and Ramsey stayed at Illinois for ten days, and then was pulled away by the Radiation Lab. And that's all he spent at Illinois.

Aaserud:

But you saw him there.

Koch:

No, I didn't know who he was. I've heard this story since. Then, of course, almost the entire department was devastated by the Radiation Lab or Los Alamos. There you had all the important players. Wheeler Loomis, for example, went to the Radiation Lab, I think in about 1942. He had induced people to come to Illinois and then when people were pulled away, he, according to Lazarus, made the comment that, "That's enough, we've contributed enough to the cause," and he said, "That's absolutely the last person that's going to leave." Then what happened a few weeks later, he turned around, after having made that statement — he left himself. I think Lazarus is going to quote him in his history of the Illinois physics department.

Aaserud:

There actually exists a short history by one of his students that relates that episode.

Koch:

Yes. And I think just about every able bodied person in the department left. Usually people got excused from the war effort because there was something medically wrong with them. In fact, I was courting my wife at the time, because I met her at Illinois. In fact, we got married on the 3rd of February, 1945, so it was a year after I had gotten my degree and a year after she got her Bachelor's degree at Illinois in home economics. So her family was very suspicious of how I could be avoiding this war effort when every young able bodied person was involved — there must be something wrong with me! And when I went to England during the war and could tell no one what that mission was all about — very secret — again they were all very suspicious of me. And it was an unusual experience for me when, at Illinois, after we had this photo fission project, and after the Alamogordo test, the head of the Met Lab in Chicago called me. Apparently this was a routine thing. When that Alamogordo shot went off, he called each of the project directors. I was a project director, of a project that had three people on it, but you know, he must have called large laboratories to tell the project directors. Well, he called me, and he said he had a message for me. I may not understand the message, but I should think about it for a while. He gave me a message, and I don't remember what it was. It was something like "The Italian navigator has landed and he finds the natives very friendly," or something like that. That was to indicate that the bomb designed by Fermi had gone off and was successful. But you asked about the department. Jerry Kruger's wife had a father who was a German general, so Kruger was suspect and therefore he was not involved in the military. He served as chairman of the department in place of Wheeler Loomis. Jerry Almy, I think, had bad eyes. There was something medically wrong with him. So Jerry Almy took Kerst's place, and he then advised me on my thesis while Kerst was gone, and then the two of them advised me pretty much, but Almy took over while Kerst was at Los Alamos. That's probably enough for the department. Not many students there.

Aaserud:

How independently did you work, on your dissertation in the first place?

Koch:

Almost completely by myself.

Aaserud:

Yes, just the four of you.

Koch:

We had a very nice machine shop in the department, and they would make everything, you know, ion chambers and so on. So between them making the parts for me, I assembled them and made my own amplifier, and did the research. We were very careful about radiation, you know, making sure that we didn't get ourselves dosed. In that respect, we really didn't take any chances.

Aaserud:

Even by today's standards, you think?

Koch:

Yes. That's right. And the four of us, none of us went into the Army. We all worked on this project. But I guess it was one of the few projects that continued during the war. And because physics, you see, had almost no women in it, the department depleted to almost nothing during the war.

Aaserud:

How many were you when you were at the smallest?

Koch:

I don't know. I wouldn't know how to guess.

Aaserud:

To what extent were you kept up on the war-related activities in physics?

Koch:

Not at all. Now, the first thing that I found exciting on that was a set of notes that Bill Stevens at the University of Pennsylvania had put together. A number of physicists took it as a challenge to see if they could figure out how a bomb worked, and what kind of information was known in the open literature, in order to see what the enemy might know about the war effort in the United States. So the Stevens effort was interesting. Then the Smyth Report came out in about 1950 or so. That gave great details about the bomb and the kind of impact a bomb would have. That was all very revealing. But before that we knew nothing.

Aaserud:

You participated but you didn't know the broader frame of things, so to speak.

Koch:

No.

Aaserud:

What about research in the department generally during those early years? Of course, it was Kerst and the betatron, but there were also other activities.

Koch:

The other major research project was Goldhaber's. Maurice Goldhaber had neutron sources. Those were neutron sources that he had gotten in the late thirties, and I remember a graduate student by the name of Stanley Klaiber. Klaiber was a student of Goldhaber's and he would set up his counters — boron trifluoride counters — and their counts were counts that were maybe a count every two hours. So they would set their equipment, go off to the movies, come back, and the rest of us would be working feverishly to get our research done, and he would saunter in, kid us about how hard we had to work. Goldhaber also had a graduate student by the name of Yalow — and I think Roz Yalow was Goldhaber's student — and she I guess was about the only person who eventually got a Nobel Prize from those early days. But she got it in biomedical research here in New York City. That's about all in the way of research in those days. It was not a large department. Its role in life was to teach engineers engineering physics. Illinois has always had a large engineering department. The engineering department always wanted to take over the engineering physics teaching, and Wheeler Loomis always resisted that. It, of course, gave the motivation for having a large number of staff people in physics at Illinois. That's why he could hire all the people he did.

Aaserud:

Yes, right. For the time the department wasn't small, of course. It was one of the major departments in physics in the country.

Koch:

That's right.

Aaserud:

While you were a graduate student you were a research assistant, correct?

Koch:

Yes.

Aaserud:

What did that involve?

Koch:

Just working for Kerst.

Aaserud:

Including your dissertation.

Koch:

Yes, and working on this NDRC project.

Aaserud:

During the war did you feel any effect of the voluntary restraint on publications? Did that affect you at all?

Koch:

No. Because of the work that we had done — depth dose and so on — none of that affected us. I did go — let's see, when was that? After the photo fission experiments — I guess it must have been before the Japanese War ended — I went down to Oak Ridge for six months to work on their reactor. I worked on the reactor modulator. It consisted of a small centrifuge top that had indium sectors on it. So you would provide this absorber and it would vary in its absorption properties because of these indium plates that would go under shield and then out from shield. It was kind of fun to figure out how to get a top like that to be operated on air blasts. But I spent six months there working with a man by name of Ernie Wollan and Alvin Weinberg. Sudak, who is in the City University I believe, was there. I've forgotten other names. It was an interesting group. I remember, outside of my window, seeing a reactor being assembled, where they took plastic cubes with uranium in them. They stacked these in a cube, a bigger and bigger cube, and then they saw the multiplication of the neutrons. But that was all, to my way of thinking, done quite casually, because I could see them working out there, stacking these things up. But no accident happened. But I was just there for that short period. Then I came back to Illinois and was a member of the team to make the 80 MEV betatron, which was the forerunner of the 300, so we built that model, the 80 MEV. The interesting thing of that time period immediately before the war and after the war was that Kerst had such resentment against the General Electric Company.

Aaserud:

Yes, he came from there, didn't he?

Koch:

Well, what he had done was, he was in the physics department at the University of Wisconsin, and got his PhD there, and then got a job with the GE X-Ray Corporation in Chicago. And whether he had gotten the idea immediately before that or not — I think he did — for the betatron, I think one of the reasons for going to the GE X-ray Corporation was to be permitted to work on a betatron. But I believe the result of that was that they didn't let him work on the betatron. I mean, they were commercially oriented and wanted to sell X-ray machines. So then, I think it was that that resulted in Wheeler Loomis hiring Kerst for Champaign-Urbana and I think that's where he built the 2.3 million volt betatron. When he built that, he then went to the General Electric Company to see if they would build a 100 MEV betatron. He took his 2.3 million volt betatron to Schenectady.

Aaserud:

That was before you came to Illinois?

Koch:

Oh yes, just before, I think, a year before. He went to Schenectady and designed a 100 MEV betatron with an engineer at GE called Westendorp, a top-notch engineer, and they designed this machine in great detail. Then the management at GE said, "We're not going to make that investment. That thing's not going to work." So then Kerst got very upset. They did agree to making a 20 MEV betatron, so they made the 20 MEV betatron, and then he insisted that he wanted to leave: if they weren't going to build the 100 MEV, to hell with them. So he then took the 20 MEV betatron back to Illinois, and then in December or November of that year, brought it in boxes, and then that's when I started working with it. We unpacked the boxes and assembled the machine, and that was the machine that GE had built, and it was Westendorp that had made the sealed-off betatron accelerating tube. There was also a super glass blower at GE, a man by the name of Klinger, and Klinger was just a superb glass blower and he sealed the thing off. But this resentment against GE was a very basic thing to Kerst, and I would suspect it was the thing that always made Kerst feel like he couldn't trust people. He certainly felt that the GE people had done him dirt. It was not too long thereafter that GE, after the 20 MEV betatron worked so well, built the 100 MEV betatron. Now, the 100 MEV betatron was eventually converted into a 180 MEV betatron. Now, that 180 MEV betatron was bought by me down at the Bureau of Standards.

Aaserud:

From GE?

Koch:

From GE. And Ed Condon was the director of the Bureau of Standards, and Ed Condon hired me from Illinois and was eager to get into this fascinating new field at the Bureau of Standards, so they also bought a 50 MEV betatron from GE. You know, money was no object. We bought these machines. I saw that 180 MEV betatron several weeks ago operating at the Bureau of Standards yet. It became the first large aperture synchrotron light source. It had a 33 inch radius, and the aperture was quite large, and was an ideal source of synchrotron light radiation from a very small beam — small in diameter, small source, and a continuum, and available in a vacuum, high intensity. They now have increased the energy to something like 220 MEV. It's a synchrotron and it's used for synchrotron light.

Aaserud:

The same machine as you brought there?

Koch:

Yes.

Aaserud:

To go back to Illinois again, to what extent did both theoretical work and experimental work, center around the betatron? To what extent was it the betatron that determined what was done there in physics?

Koch:

The two major sources were the cyclotron that Jerry Kruger had built, and the betatron. Those were the two major facilities. There were smaller programs, like the one that Goldhaber had. But there you see a concentration in nuclear physics at Illinois. Illinois had in the thirties developed a big reputation for acoustics. They had a pioneer by the name of Watson who retired just about 1940 as I remember. It was then the big influx of people that brought the new emphasis on accelerators and nuclear physics, that pretty much dominated the Illinois physics scene until the time that Fred Seitz came, and Seitz came, I would guess, in about 1951. He was the chairman of the department. And then of course they've been pioneers in solid state condensed matter research ever since. The emphasis on nuclear physics pretty much had to stop because I think there was an unwillingness to have a big machine built close to the department that would dominate all of their activities. They would then become slaves to that very big machine. And I think that was the point that Lazarus made about his history of the early days of Illinois.

Aaserud:

So the machines reached kind of a critical size and then —

Koch:

— that was as far as you could go. They did make some proposals on microtrons and they may have built a microtron. This is a DC magnet with a cavity and a racetrack — a racetrack microtron. The group that I established at the Bureau of Standards is just now involved in making a, I think, two billion volt microtron. But that's pretty much what limited Illinois.

Aaserud:

To what extent was there a connection or a collaboration between universities or research places in the Midwest at the time?

Koch:

There was excellent collaboration, partly because each of the departments was relatively small, and they all realized that the East Coast and the West Coast were where much of the action was, with E. O. Lawrence on the West Coast and Columbia being so strong — Princeton, Brookhaven. The University of Indiana, University of Chicago, Illinois, Iowa State, University of Wisconsin, were all within a 300 mile radius. So what you found then was department members taking their graduate students, and they'd go for a one or two day seminar at another school, and then this would rotate, so the Midwest did a lot of that kind of thing. They didn't have enough equipment, so that there was much in the way of people from one university going to another university doing research. Each tried to acquire their own equipment, and equipment was relatively small so that they could each pretty much afford to do that. It was only in later days that there was this big swing towards collaboration on very big machines, where you leave your department and go for summer periods or whatever. But Illinois being a terrible place climate-wise — summers are abominable there — people would look for ways of getting away during the summer, and you would go to Los Alamos and other laboratories.

Aaserud:

Did you have an ongoing seminar for example that rotated, things like that?

Koch:

No, each department had their journal club and their own colloquium so there were weekly colloquia where outside visitors were brought in to speak, and then people from different neighboring universities would come in those colloquia. The journal club was the thing that graduate students had to suffer through — to take a Physical Review article and then report on it in the journal club. It was amazing how, after six months of having suffered, you then gradually started to get the lingo and gradually understood what was going on. The first few lectures you went to, you couldn't understand at all what was going on.

Aaserud:

The transition from graduate student to assistant professor in 1944, how did that come about?

Koch:

There was nothing unusual about it because I was the only character there, the only one who could be given an appointment. Loomis, because the investment in the few people that were involved with Kerst, didn't want to lose any of those people, and so he would promote you and entice you, and I think he was a little bit upset when I proposed to go to the Bureau of Standards. They tried to dissuade me, but I thought it would be a good opportunity for me personally, and it's turned out to be good.

Aaserud:

Was that Condon? Was he already —

Koch:

— he was at the Bureau of Standards.

Aaserud:

So you had a personal connection with him?

Koch:

Yes, when I was appointed director here at AIP, he happened to be on the governing board of AIP, and I was introduced to the board at a meeting in a New York hotel, and Condon, after I was introduced, said he wanted everybody to know that he had discovered me, by bringing me to the Bureau of Standards, and he was now pleased that he could approve my appointment at the American Institute of Physics.

Aaserud:

How did you get to know him?

Koch:

It's interesting that the department at Illinois, as Dave Lazarus keeps on pointing out, was very much of a family affair. The Bureau of Standards was almost the same way in that it at the time was a relatively small institution. We were all on Connecticut Avenue, in Washington and I don't know if you have heard stories about Physical Society meetings where the Bureau of Standards was known for the beautiful azaleas, and the spring meeting of the Physical Society was always in Washington.

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