Posts Tagged ‘Smyth Report’


Los Alamos and the Smyth Report

Wednesday, August 15th, 2012

Everyone has spent a lot of time talking about the 67th anniversaries of Hiroshima and Nagasaki. But last Sunday (August 12) was also another anniversary: the 67th anniversary of the release of the Smyth Report.

Richard Tolman, advisor to General Groves and one of the security editors of the Smyth Report, and Henry DeWolf Smyth, in 1945

The Smyth Report is one of the great documents of the nuclear age. Written by the Princeton physicist Henry DeWolf Smyth, it was an official history of the Manhattan Project that was released to the public only days after the bombing of Nagasaki. From the very beginning of the document you can tell it is playing a very delicate game with regards to openness and secrecy. Let us juxtapose the Introduction, written by Smyth, with the Foreword, written by General Groves:

SmythThe ultimate responsibility for our nation's policy rests on its citizens and they can discharge such responsibilities wisely only if they are informed. The average citizen cannot be expected to understand clearly how an atomic bomb is constructed or how it works but there is in this country a substantial group of engineers and scientists who can understand such things and who can explain the potentialities of atomic bombs to their fellow citizens.

Groves: All pertinent scientific information which can be released to the public at this time without violating the needs of national security is contained in this volume. No requests for additional information should be made to private persons or organizations associated directly or indirectly with the project. Persons disclosing or securing additional information by any means whatsoever without authorization are subject to severe penalties under the Espionage Act.

What a fun game, eh? "Here is some important information, because it is necessary for democracy and sound policy. Also, if you go even an inch beyond what is written in here, we'll put you in jail forever."

Even the title of the report reflects this push and pull of secrecy. On the face of it, it's got a dull, boring, bureaucratic title (which matches tone of the report itself, which is no great read):

"A General Account of the Development of Methods of Using Atomic Energy For Military Purposes Under the Auspices of the United States Government, 1940-1945." It doesn't exactly roll off the tongue, does it? You can see why in the Princeton University Press edition, they dubbed it Atomic Energy for Military Purposes (still a dull title), and everyone just calls it the Smyth Report. (Note: it's pronounced Smythe but spelled Smyth.)

But here's a little-known fact: that long, awful title wasn't meant to be the title. It was supposed to be the sub-title — the actual title was so sensitive that it was going to be stamped on at the last moment before distribution. In the hubbub before its release, the stamp was essentially never used, and the sub-title became the title.

So what was the original title? Recently I found a rare copy in the Manuscripts Division of the Library of Congress that contains the original title with the original stamp:

The original title was ATOMIC BOMBS, to be applied in a bright red stamp. Now how cool is that? In a way, this is Manhattan Project trivia, but really it points towards a deeper truth about the Smyth Report: every single aspect of it — even its title! — was shaped by the question of secrecy. The story of the Smyth Report is a fascinating one, and I spend the good part of a chapter in my forthcoming book talking about it.1 The idea of its creation, the process of its creation, and the debate over whether it should be released at all, much less the consequences of that release, are all completely vital stories in their own right for making sense of secrecy and publicity in the immediate postwar period.

I want to focus on just one little part of that, though: what Smyth did, and didn't, write about Los Alamos, the most secret site in a system of secret sites.

On February 1, 1945, Smyth sent the first draft of the history of Los Alamos to none other than J. Robert Oppenheimer.2 (As if Oppenheimer didn't have enough to do.)

"I am at last ready to send you the first draft of what I have written about the project at Y," Smyth explained. (Project Y was the official code name for the Los Alamos lab.) In the habit of all academics, then and now, he apologized for being a bit tardy. He explained that it would be swell if Oppenheimer could have Richard Feynman take a look at the draft. He also noted that:

You will notice that I have omitted nearly all numerical values for constants. This is a departure from my original intention, but I do not see that their inclusion would really add much to the usefulness of this document and it might necessitate a complete revision before publication.

This is interesting: Smyth's "original intention" was to write the entire report without any regard for secrecy. Later, after everyone agreed the draft was more or less correct, he'd cut out all of the secret stuff, once it was decided what the secret stuff would be. In this case, though Smyth has pre-censored himself on numerical constants — but still written it as if he hadn't. A weird genre of writing, no?

Nobody got back to Smyth on this letter; they were too busy. Smyth wrote Oppenheimer again in April 1945, sending another draft.3

He had heard from Groves and James Conant that Oppenheimer "did not like the chapter as a whole" but "were unable to give any report of specific criticisms." Smyth asked for any that Oppenheimer had, and noted that: "I have not found the writing or this report an easy assignment."

Smyth also explained some of the major omissions that had been made from the previous draft:

As I anticipated, the critical comment on the choice of the site will be deleted. I may say that I inserted this comment and similar comment in other chapters with the expectation that they would be removed before publication but with the feeling that it was desirable to record the existence of such opinions in the original draft.

All discussion of ordnance work is also to be removed. There is no objection to including the general statement of the ordnance problem and all the other parts of the problem, but the approaches to solution that have been made will be omitted. On the other hand, the feeling is that there is no objection to including the nuclear physics.

The General believes that the metallurgical work and a considerable amount of the chemistry work should be excluded on the ground that it would be extremely difficult for the average scientist to carry out any of this work without supplies and material which would not be available to him. I am not entirely clear how this criterion should be applied, but it probably means the elimination of the metallurgical work on plutonium and at least of some of the chemistry. I shall simply have to write a revised version and discuss it in detail with General Groves and Dr. Conant.

One other general comment which they made is that more names should be included. While this comment applies more forcibly to some other chapters than to that on Y, it is a point to be borne in mind in criticizing what I have written.

I don't know what the "critical comment on the choice of site" refers to — except maybe to the fact that Los Alamos is in the middle of nowhere, which has its disadvantages as well as its advantages — but the rest is pretty straightforward. Ordnance — the actual work to design the atomic bomb, esp. relating to implosion — was out. Metallurgy and chemistry? Out and out.4 Basic nuclear physics? In!

So let's get this straight: out of all of the work done at Los Alamos, all that gets past the censor is basic nuclear physics. And the implications of removing metallurgy and chemistry here probably means almost nothing will be written about Hanford, either. The final report has exactly two paragraphs on Hanford, despite it consuming a fifth of the Project resources. Which also meant cutting out the legions of chemists, engineers, and metallurgists who worked on the project in that capacity.

And so one suddenly sees that there is more missing from the Smyth Report than there is revealed in it.

Oh, but also: add more names of people. Why? Because Groves was afraid that scientists (and contractors) would seek credit after the war ended if they didn't feel it was properly given to them — and in the act of seeking credit, they might give away secrets.

The Smyth Report as published by Princeton University Press.

Oppenheimer finally did write back to Smyth about this draft, apologizing for never writing back to his first letter, in April 1945.5 Oppenheimer wasn't particularly pleased with it. What's interesting about his objections and corrections to it are that they are almost completely concerned with things which were cut from the final draft for security reasons anyway. There's a lot about implosion (what prompted it, who came up with it, etc.), for example, and implosion was completely omitted from the final Smyth Report.

If you're interested in Los Alamos project history, you might find Oppenheimer's comments interesting — Oppenheimer's history of implosion is from a rather unique vantage point, since they hadn't actually even tested the bomb yet ("In the past months I think we have had the fundamentals of implosion licked, and the future in this field looks bright"). Oppenheimer's list of corrections has a lot of interesting bomb arcana in it; a selection here to give a flavor for it, along with some of the more interesting corrections:

Page 2, line 9. "December" should be "October."
Page 3, line 11 (from bottom). "January" should be "November." [...]
Page 9, line 10. "Mass" should be "radius."
Page 12. This is the point I have discussed above. The history of implosion is roughly thus:

It was proposed by Neddermeyer at the April conference, and some arguments were given by him to show that it would give a faster assembly than the gun; work was carried out on exploratory basis which gave misleadingly hopeful looking results. The matter was considered again by von Neumann in the Fall of 1943; he expressed the opinion that the implosion would work better with high charge to mass ratio, and might avoid the necessity for extreme purification of plutonium, at least or very small gadgets, because it would give such a rapid assembly. The compression on the material resulting from high velocities was then pointed out by Teller and investigated by Bethe. After much struggle and argument the implosion project was adopted with over-riding priority in late 1943. The later history I have outlined above. [...]

Page 25, line 15. I would use the word "surprise" rather than "setback," but that is a matter of judgment. [...]
Page 32, par. 3, line 1. The 3000 ft/sec figure always referred to 49. The 25 velocity was not set until firm limits on the spontaneous fission of the isotopes enabled us to take 1000 ft/sec. This occurred early in 1944. [...]
Page 42 line 10. The theoretical behavior is well known, but we are not sure that the theories are right.

The final version of the chapter on Los Alamos, "The Work on the Atomic Bomb," is comparatively barren, when compared to the nitty-gritty that Oppenheimer went into above. It has a nice, but brief administrative history (why the lab was created, why the site was chosen — no critical comments, who was in charge of it), the world's most basic discussion of basic bomb design issues (critical mass, tamper, efficiency, and an extremely vague statement on the gun-type design), and then more or less doesn't advance the timeline beyond April 1943.

Like so many things, it's clear that Smyth, Oppenheimer, and even Feynman spent a lot of time trying to ferret out all of the facts about Los Alamos — only to see them almost completely, and silently, cut from the final publication.

  1. I should also note here that there is an in-depth study of the Smyth Report which I've benefited a lot from: Rebecca Press Schwartz, "The Making of the History of the Atomic Bomb: Henry DeWolf Smyth and the Historiography of the Manhattan Project," (Ph.D. diss., Princeton University, September 2008). Rebecca has actually looked at the original drafts of the Smyth Report, which are kept in the archives of the American Philosophical Society. []
  2. Henry D. Smyth to J. Robert Oppenheimer (1 February 1945),  Nuclear Testing Archive, Las Vegas, NV, document NV0125251. []
  3. Henry D. Smyth to J. Robert Oppenheimer (6 April 1945), Nuclear Testing Archive, Las Vegas, NV, document NV0125250. []
  4. Rebecca Press Schwartz' dissertation, cited above, notes that for many years Smyth received angry letters from chemists and metallurgists in particular complaining that they had been cut out of the official history! []
  5. J. Robert Oppenheimer to Henry D. Smyth (14 April 1945), Nuclear Testing Archive, Las Vegas, NV, document NV0125249. []

The Week of the Atom Bomb

Friday, August 10th, 2012

This week is, as you all no doubt know, the 67th anniversary of the bombings of Hiroshima and Nagasaki. These anniversaries happen to fall on the same days of the week as the original ones. So the bombing of Hiroshima on August, 6, 1945, was a Monday -- just as with August 6, 2012. The bombing of Nagasaki, August 9, was a Thursday. The Smyth Report would be released on August 12, a Sunday. Hirohito's "surrender" message would come on August 15, the next Wednesday.

For some reason, conceptualizing all of this as happening within a few weeks makes it seem awfully short in time. What a week that would have been.

Headline for the New York Times, August 7, 1945.

One of the things I really enjoy doing as an historian is looking through old newspaper front pages. You find so much out about past societies that way -- the juxtaposition of related and unrelated articles provides a fascinating kaleidoscope of the day in question. Put a bunch of different newspaper headlines together, from different parts of the country, and you get an even more interesting portrait of a specific time and place.

In closing out the 67th anniversary of the Week of the Atom Bomb, I want to share a number of newspaper front pages with you. I'm limited in what I can conjure up, but I've managed to collect some 38 different front pages from newspapers in different parts of the country for the work week of August 6th through August 10th, each of which I thought was interesting or revealing in some way. Some of these newspapers will be immediately familiar to you -- the New York Times, the Washington Post -- some will be quite obscure -- the Big Spring Daily Herald, from Big Spring, Texas, for example. Some represent quite specific markets: the Atlanta Constitution, for example, is an African-American newspaper in the age of segregation, and there are interesting differences between how they cover the issue versus the big city newspapers or the small town newspapers.

One additional point: the headlines are different, but the stories are almost exactly the same. This is because in the first week of the bomb, all of the stories were essentially written by William L. Laurence of the New York Times and released to the press by the Army. Not until the Smyth Report was released, on August 12th, do you start to see much independent reporting. The content of the "official" stories is interesting, but today I just want to focus on the headlines.

In an effort to keep this post from sprawling out forever, I've arranged all of the images in a little gallery below. If you are reading this on an RSS feed or an aggregator, you may have to visit the main site to view these.

August 6, 1945: Big Spring Daily Herald, Big Spring, Texas.

Picture 1 of 32

"Five Cities Hit, One By New Bomb": I find it interesting here that they've explicitly lumped the firebombed cities in with the atomic bombing of Hiroshima. The subheadline, "Atoms Harnessed for Destruction," is more vivid. But note that far more space is given to the firebombing than the atomic bomb -- likely because they had only just received word of the atomic bomb and had to fit it in later. There is an interesting ambivalence in describing the "helpless Japs" in the headline about the firebombs.

There are two images from the set that I'd really like to draw your attention to. The first is from the August 9, 1945, edition of the Indiana Evening Gazette, from Indiana, Pennsylvania. (A bit confusing, that.) It appears to have been used in a lot of newspapers that day in different parts of the country, so it probably originates on the AP wire service. Anyway, here's the image:

"DEATH KNOCKS AT EVERY JAP'S DOOR," the main announcement reads. The caption is completely insane:

The utter desolation facing the Japanese, unless they surrender, as result of development of the atomic bomb is illustrated on the map above. Scientists say that if 1000 of the new weapons were exploded within each of the five circled areas, they would destroy virtually all life and property in the enemy homeland.

It's not every day that you see small-town American newspapers cheerfully contemplating genocide, is it?

The second detail is a little illustration from the Kingsport Times, in Kingsport, Tennessee, published on August 9, 1945. It attempts, in visual form, to make sense of the force of an atomic bomb as described by President Truman (" ...Ruin from the Air, The Like of Which Has Never Been Seen On Earth"):

On the left, a colorful illustration of an atomic bomb going off under the Empire State building: "The atomic bomb is the most terrible engine of destruction every conceived. One pound of U-235 could blast a great city, like New York, off the face of the map."

In the middle, a train being blasted to oblivion: "To get a comparable explosion from TNT, you would have to set off 15,000 tons, or 300 carloads of 50 tons each. If U-235 exploded at TNT's speed, pressure would be 1,000,000 times as great." I don't really know what they mean by the last line, there, but going from "trainloads of TNT' to "an exploding train" is somewhat imaginative.

On the right, a dead fleet — presaging Operation Crossroads. "Exploded amid a great fleet at sea, an atomic bomb would sink most of the ships, send a great tidal wave shoreward. Most tightly compartmented ship would be crushed by air pressure." Some original typos, there, but you get the picture.

As I've mentioned previously, there was a tremendous mixing of exaltation and  anxiety that first week of the bomb. It wasn't just one thing or the other; it wasn't all positive. Looking at these front pages, you see a real mixture of expressions, and a real diversity of types of coverage, even given the limitations imposed by secrecy. For some, the story is the secrecy itself — for others, the bomb gets mixed into an existing narrative about firebombingOut of the mixture of these narratives, our "standard narrative" of the history of bomb is derived. But it's all too easy to turn that into a condensed, one-size-fits-all assessment of how Americans thought about the atomic bombs, when there was quite a diversity of opinion and expression, even from the start.


What Bohr told Beria

Wednesday, August 1st, 2012

In June 1945, Niels Bohr left the United States to return to Copenhagen. He had spent the end of World War II at Los Alamos, mostly as a "father confessor" to the physicists there, but also giving some substantial help on the work of the bomb (he was the one who arbitrated a dispute over which neutron initiator should be used in the implosion bomb).

Rare color photograph of Niels Bohr and his wife Margrethe. Courtesy of the Emilio Segre Visual Archives, from the Dodge Collection.

Ever since he was whisked out of Denmark, Bohr had also been trying to advocate for a postwar international control scheme for nuclear weapons. He tried to convince Winston Churchill, to no effect, and was somewhat successful in convincing Roosevelt on the soundness of such a scheme.

He had a much greater influence on the Los Alamos scientists, like Robert Oppenheimer, and Bohr's line of thinking can be seen very plainly in the Acheson-Lilienthal Report that Oppenheimer would later contribute to. At the heart of Bohr's approach was the free exchange of scientific information and scientists — an end of secrecy, he argued, would make it impossible to have a secret nuclear arms race. (This was the same opinion that Vannevar Bush and James Conant had independently come to, as remarked previously on this blog.)

By November 1945, Bohr was feeling quite stressed about how the bomb was being handled. The British Ambassador to the United States, Roger Makins, reported to General Groves on November 7 that:

Bohr is disturbed over the political developments with regard to the atomic bomb. He feels the press treatment of it is creating unnecessary mystification and ill feeling. He cannot understand why so much play is being made over 'secrets' which may or may not be shared with the Soviet Union. He considers that there are no essential secrets to the Soviet Government which are not known to them already, and believes that the United States Government's sole advantage is in production and production experience.1

So in a way it is not surprising that the Soviet Union targeted Bohr as a possible intelligence asset. After all, the "let's get rid of secrecy" argument is not too far from the "let's share the bomb" argument, which is what had motivated Klaus Fuchs and Ted Hall and numerous others. It is also not surprising, then, that Bohr agreed to meet with a Soviet physicist, Yakov Terletsky, when he desired a conversation about the postwar atomic situation — Bohr was willing to talk to anyone on such a subject.

Lavrenty Beria on the cover of Time magazine, 1953. Creepy looking guy.

But Terletsky was not just a random interested party — he had been sent to Bohr by the NKVD, the organization led by Lavrenty Beria and the predecessor of the KGB. 

This week's documents pertain to the Soviet side of the Bohr-Terletsky interview. The one that I have scanned comes from the same Russian nuclear history book I discussed last week, though the copy in the book is incomplete. I have managed to scrounge up copies of these documents from various places on the web and in print and have performed a rudimentary translation on them. (As always, I am happy to have my translations corrected. The original Russian is in the footnotes.)

On the left, the letter to Stalin from Beria. On the right, an excerpt from the Bohr-Terletsky interview.

The first document is a letter from Beria to Stalin, reporting on who Niels Bohr is and what they've been up to with him. The Wilson Center has this dated in late November 1945, but it may be sometime in early December 1945 as well.2

Label: "Special files", "Top Secret." No. 1372-B
[Handwritten:] Make known to Merkulov. L. Beria. 8/X11 [8 Dec.].

Comrade STALIN I.V.

The famous physicist, Professor Niels BOHR, who was involved with the work on the atomic bomb, has returned from the USA to Denmark and started to work at the Institute for Theoretical Physics in Copenhagen.

Niels BOHR is known as a progressive-minded scholar and a staunch supporter of the international exchange of scientific achievements. This gave us grounds to send a group of workers to Denmark, under the guise of investigating equipment of Soviet scientific institutions taken away by the Germans,  to establish contact with Niels BOHR to seek information on the problem of the atomic bomb.

The comrades sent: Colonel VASILEVSKY, Candidate of Physical and Mathematical Sciences TERLETSKY, and engineer and translator ARUTYUNOV. Having found appropriate approaches, they have got in touch with BOHR and organized two meetings with him.

The meetings were held on November 14 and 16 under the pretext of TERLETSKY visiting Soviet scientists at the Institute for Theoretical Physics.

Comrade TERLETSKY said to BOHR that while in transit in Copenhagen, he felt it his duty to visit the famous scientist, and that he warmly remembered BOHR’s lectures at Moscow University.

During the interviews, Bohr was asked a series of questions prepared in advance in Moscow by Academician KURCHATOV and other scientists involved in the atomic problem.

Attached are the list of questions, BOHR’s answers, and an evaluation of the responses by Academician KURCHATOV.

Printed in three copies.
Copy No. 1 – addressee.
No. 2 – Secretary of the NKVD.
No. 3 – Section "C".
Operator Sudoplatov.
Typist Krylov.

Yakov Terletsky was a physicist from Moscow State University. In Richard Rhodes' Dark Sun, Terletsky described his meeting with Beria the first time, in 1945, in vivid detail:

He was of average height, aging, with a skull that narrowed slightly toward the top, with severe features and no shadow of warmth or a smile. Beria did not give the impression I had expected from seeing his portraits before, of a young, energetic member of the intelligentsia wearing a pince-nez. Everyone sat down at the big conference table. In the middle of the table was a large white marble ash tray in the shape of a polar bear with little ruby eyes. That was the only object on the long table... it was obvious that no one used it.3

Terletsky wasn't actually the best guy to send — he was a total novice to nuclear physics. His expertise was in statistical physics, and he had less than a week's understanding of the basics behind nuclear technology. Beria wanted him sent, though, rather than a more experienced physicist. A suspicious master of human intelligence, Beria knew that Bohr would also learn from the exchange — and he didn't want Bohr to know anything about what the Soviets did or did not know about the bomb. 

Yakov Terletsky

Terletsky asked Bohr 22 questions. I've included a few of the most interesting ones here; these come from the Wilson Center's Cold War International History Project.

1. Question: By what practical method was uranium 235 obtained in large quantities, and which method now is considered to be the most promising (diffusion, magnetic, or some other)?

Answer: The theoretical foundations for obtaining uranium 235 are well known to scientists of all countries; they were developed even before the war and present no secret. The war did not introduce anything basically new into the theory of this problem. Yet, I have to point out that the issue of the uranium reactor and the problem of plutonium resulting from this — are issues which were solved during the war, but these issues are not new in principle either. Their solution was found as the result of practical implementation. The main thing is separation of the uranium 235 isotope from the natural mixture of isotopes. If there is a sufficient amount of uranium 235, realizing an atomic bomb does not present any theoretical difficulty. ... The Americans succeeded by realizing in practice installations, basically well-known to physicists, in unimaginably big proportions. I must warn you that while in the USA I did not take part in the engineering development of the problem and that is why I am aware neither of the design features nor the size of these apparatuses, nor even of the measurements of any part of them. I did not take part in the construction of these apparatuses and, moreover, I have never seen a single installation. During my stay in the USA I did not visit a single plant. While I was there I took part in all the theoretical meetings and discussions on this problem which took place. I can assure you that the Americans use both diffusion and mass-spectrographic installations.

Bohr played his cards close to his chest, here. He told Terletsky nothing that is not already in the Smyth Report. He later explained that you could feed the material from one plant to another, which is also in the Smyth Report. (Did Bohr truly never "visit a single plant"? I'm not sure. This oral history suggests that he did briefly visit Oak Ridge in 1944, but it's the only account of that I've seen, and the interviewee may be mistaken about the timing of that. If Bohr did visit Oak Ridge, it would be an interesting thing in the context of this interview.) Bohr's line was also very conducive to the control issue — the production of fissile material, he's arguing, is not a matter of secrecy, but of technology. In this and many other exchanges, one gets the impression that Bohr is trying to convince Terletsky — and his handlers, whom Bohr could not be so naive as to not know existed — of the wisdom of international control.

 8. Question: How many neutrons are emitted from every split atom of uranium 235, uranium 238, plutonium 239 and plutonium 240?

Answer: More than 2 neutrons.

9. Question: Can you not provide exact numbers?

Answer: No, I can't, but it is very important that more than two neutrons are emitted. That is a reliable basis to believe that a chain reaction will most undoubtedly occur. The precise value of these numbers does not matter. It is important that there are more than two.

A direct technical question with an evasive answer. Did Bohr know the precise number of neutrons? Undoubtedly. Would he tell? No. Why not? Because "the precise value" actually does matter for critical mass calculations. His dismissal of the importance of this value constrains his discussion, again, almost to the level of the Smyth Report. (He may have gone a tiny bit beyond, but not in a serious way. The Smyth Report does not say the amount of neutrons released per fission, but it does say that it was known in 1940 that it was between 1 and 3. Obviously it couldn't have been less than two, though, if the reactor and bomb were going to work. So Bohr has not really said much, here.)

15. Question: Does the pile begin to slow as the result of slag formation in the course of the fission of the light isotope of uranium?

Answer: Pollution of the pile with slag as the result of the fission of a light isotope of uranium does occur. But as far as I know, Americans do not stop the process specially for purification of the pile. Cleansing of the piles takes place at the moment of exchange of the rods for removal of the obtained plutonium.

This is an odd question with a confused answer. It's a reference to so-called "Xenon-poisoning" in the first industrial-sized nuclear reactors at Hanford. Xenon-135, a fission product, builds up as the reaction commences. However, it is also a neutron absorber, so the reactions tend to slow down as more of the isotope is created. This is the "pollution" Bohr refers to. It was a major issue at Hanford. The way to fix it is to cycle through the fuel loads more often. So Bohr's answer is not very clear, though he may have just been ignorant on Hanford issues.

Xenon-poisoning was mentioned in the first edition of the Smyth Report, but deleted from subsequent re-printings by General Groves. The discrepancy was noticed by the Soviet translators — yet another case where an attempt at secrecy actually highlighted what was meant to be hidden.

19. Question: Of which substance were atomic bombs made?

Answer: I do not know of which substance the bombs dropped on Japan were made. I think no theorist will answer this question to you. Only the military can give you an answer to this question. Personally I, as a scientist, can say that these bombs were evidently made of plutonium or uranium 235.

I'm pretty sure Bohr is lying here. It seems highly unlikely that he was unaware of the differences between the gun and implosion bombs, or the fact that there were both uranium-235 and plutonium bombs used.

 20. Question: Do you know any methods of protection from atomic bombs? Does a real possibility of defense from atomic bombs exist?

Answer: I am sure that there is no real method of protection from atomic bomb. Tell me, how you can stop the fission process which has already begun in the bomb which has been dropped from a plane? It is possible, of course, to intercept the plane, thus not allowing it to approach its destination — but this is a task of a doubtful character, because planes fly very high for this purpose and besides, with the creation of jet planes, you understand yourself, the combination of these two discoveries makes the task of fighting the atomic bomb insoluble.

We need to consider the establishment of international control over all countries as the only means of defense against the atomic bomb. All mankind must understand that with the discovery of atomic energy the fates of all nations have become very closely intertwined. Only international cooperation, the exchange of scientific discoveries, and the internationalization of scientific achievements, can lead to the elimination of wars, which means the elimination of the very necessity to use the atomic bomb. This is the only correct method of defense.

I have to point out that all scientists without exception, who worked on the atomic problem, including the Americans and the English, are indignant at the fact that great discoveries become the property of a group of politicians. All scientists believe that this greatest discovery must become the property of all nations and serve for the unprecedented progress of humankind. You obviously know that as a sign of protest the famous OPPENHEIMER retired and stopped his work on this problem. And PAULI in a conversation with journalists demonstratively declared that he is a nuclear physicist, but he does not have and does not want to have anything to do with the atomic bomb. ...

We have to keep in mind that atomic energy, having been discovered, cannot remain the property of one nation, because any country which does not possess this secret can very quickly independently discover it. And what is next? Either reason will win, or a devastating war, resembling the end of mankind.

Ah, Bohr really got going here — Terletsky got him on a topic where he could pontificate very freely (notice the length at which he speaks here, compared to the technical questions).

21. Question: Is the report which has appeared about the development of a super-bomb justified?

Answer: I believe that the destructive power of the already invented bomb is already great enough to wipe whole nations from the face of the earth. But I would welcome the discovery of a super-bomb, because then mankind would probably sooner understand the need to cooperate. In fact, I believe that there is insufficient basis for these reports. What does it mean, a super-bomb? This is either a bomb of a bigger weight then the one that has already been invented, or a bomb which is made of some new substance. Well, the first is possible, but unreasonable, because, I repeat, the destructive power of the bomb is already very great, and the second — I believe — is unreal.

This is an odd question to ask, with an even odder answer. That the idea of a "superbomb" (сверхбомбы, here) was out and about by this point is something I've remarked on previously. They're basically asking Bohr what he knows about the idea of a hydrogen bomb, something that was explored during the Manhattan Project. In any case, Bohr's answer is very misleading — whether because he was being deliberately misleading or because he was just uninformed, I don't know. But his dismissal of the idea that you could optimize bomb design for a larger explosion, or that you could use other materials for nuclear explosions, is completely incorrect.

22. Question: Is the phenomenon of overcompression of the compound under the influence of the explosion used in the course of the bomb explosion?

Answer: There is no need for this. The point is that during the explosion uranium particles move at a speed equal to the speed of the neutrons' movement. If this were not so the bomb would have given a clap and disintegrated as the body broke apart. Now precisely due to this equal speed the fissile process of the uranium continues even after the explosion.

This last question is a puzzler. It's unclear exactly what was asked here (something is lost in multiple translations), but it sounds a lot like they are asking about whether compressing fissile material is necessary. Bohr doesn't really answer it — he basically says that the bomb explodes a bit after it runs its reaction (which is true, but not super relevant, I don't think), when he knows, from being at Los Alamos, that compression is used during the implosion of the bomb. But again, it's hard to make sense of either the question or the response.

Kurchatov in the 1950s. Photo credit: Ioffe Physical Technical Institute, courtesy AIP Emilio Segre Visual Archives.

Lastly, we turn towards an evaluation of Bohr's responses by Igor Kurchatov, a.k.a. "The Beard," the head scientist on the Soviet bomb program. This is dated "December 1945," which is why I am suspicious about the November dating of the Beria document above (since this was attached to it).4

Answers given by Professor Niels BOHR
on questions relating to the atomic problem

Niels Bohr was given two sets of questions:

1. Concerning the main directions of work.

2. Containing specific physical data and constants.

BOHR gave some answers to the first group of questions. BOHR gave a definitive answer to the question on the U.S. methods used for producing uranium-235, which has quite satisfied Professor [Isaak] KIKOIN, Corresponding Member of Academy of Sciences, who asked this question.

Niels BOHR made a crucial point about the effectiveness of uranium in the atomic bomb. This comment should be subjected to theoretical analysis, which should be entrusted to professors LANDAU, MIGDAL and POMERANCHUK.

December 1945.

Kurchatov's analysis is interesting. Bohr's "definitive" answer on uranium-235 production is only significant if you distrust the Smyth Report. (And it makes sense that the Soviets would distrust it.) It is really unclear to me what the "effectiveness" comment is referring to — my assumption is that it refers to question 22, which is hard to parse in any event.

What's most interesting to me about Kurchatov's analysis is how positive it is, when Kurchatov surely must have known that Bohr wasn't telling them much — either because he didn't know it, or because he didn't want to tell them.

And yet, he's still writing up the operation as a big success. My guess is that he's trying to make Beria happy about everyone who participated — Bohr, Terletsky, and so on. Bohr didn't give them much information, but it wasn't really Terletsky's fault.

Bohr and Ivan Pavlov, the famous Russian physiologist, probably in the 1920s or 1930s. One wonders what they would have discussed. Courtesy of the Emilio Segre Visual Archives.

But let's flip this around: What did Bohr learn from Terletsky? If Bohr took seriously that Terletsky was representative of the interest of Soviet physicists in the bomb, he probably would have assumed that they didn't know much. The questions Terletsky asked do not reveal very much knowledge on the subject matter, and certainly don't reveal insight from intelligence sources (number 22 might hint at it, but that's it, and even then, it's not very clear).

In a sense, Beria's decision to send Terletsky was spot-on. Bohr wasn't going to tell the Soviets anything that wasn't already publicly known. Beria couldn't have known that from the beginning, but sending someone like Terletsky would have been a good way to find out for sure — if Bohr had been indiscreet or seemed like a source to be "cultivated," more contact could have followed later. Bohr's refusal to give precise numbers on the neutron emissions was his most direct case of clearly not cooperating. They likely would have been a clear signal that Bohr either didn't know technical details, or that he wasn't interested in divulging them.

Had Beria sent someone deeper into the atomic problem (like Khariton or Zel'dovitch) the line of questioning likely would have shown Bohr that they knew much more than they were supposed to. Would someone who really knew about the bomb project be able to ask those simple questions with such a straight face?

What's wonderful about reading this in retrospect is that we know that both Bohr and the Soviets knew more than they let on. This "interview" (or "interrogation") is a tremendous dance of shadows — two people trying to get information without giving too much away. And like many such exchanges, neither side likely learned very much.

Amusing Soviet fact of the day: During World War II the Red Army's in-house counter-espionage unit — which served mostly to root out perceived enemies of the people within the Army itself — was called SMERSH (СМЕРШ), an acronym of the phrase "Death to Spies!" Stalin coined this exceptionally silly name himself.

  1. Roger Makins to Leslie R. Groves (7 November 1945), Correspondence ("Top Secret") of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Folder 11: "Correspondence with Foreign Nations," Roll 2, Target 5. []
  2. Грифы: "Особая папка", "Совершенно секретно". No. 1372-Б
    Ознакомить тов. Меркулова В. М. Л. Берия. 8-Х11

    Товарищу СТАЛИНУ И.В

    Известный физик профессор Нильс БОР, имевший отношение к работам по созданию атомной бомбы, вернулся из США в Данию и приступил к работам в своем институте теоретической физики в Копенгагене.

    Нильс БОР известен как прогрессивно настроенный ученый и убежденный сторонник международного обмена научными достижениями. Исходя из второго, нами была послана в Данию, под видом розыска увезенного немцами оборудования советских научных учреждений, группа работников для установления контакта с Нильсом БОРОМ и получения от него информации по проблеме атомной бомбы.

    Посланные товарищи: полковник ВАСИЛЕВСКИЙ, кандидат физико-математических наук ТЕРЛЕЦКИЙ и переводчик инженер АРУТЮНОВ , найдя соответствующие подходы, связались с БОРОМ и организовали с ним две встречи.

    Встречи состоялись 14 и 16 ноября с. г. под предлогом посещения советским ученым т. ТЕРЛЕЦКИМ Института теоретической физики.

    Тов. ТЕРЛЕЦКИЙ сказал БОРУ, что, находясь проездом в Копенгагене, счел своим долгом нанести визит известному ученому и что о лекциях БОРА до сих пор тепло вспоминают в Московском университете.

    В процессе бесед БОРУ был задан ряд вопросов, заранее подготовленних в Москве академиком КУРЧАТОВЫМ и другими научными работниками, занимающимися атомной проблемой.

    Перечнь вопросов, ответы на них БОРА, а также оценка этих ответов, данная академиком КУРЧАТОВЫМ, прилагаются.

    Л. БЕРИЯ
    Отпечатано в 3 экз.
    Экз. No. 1 - адрестау.
    No. 2 - Секр. НКВД СССР.
    No. 3 - Отдел "С".
    Исполнитель Судоплатов.
    Машинистка Крылова.


  3. Dark Sun, 218-219. []
    Ответов, данных профессором Нильс БОР
    на вопросы по атомной проблеме

    Нильсу БОРУ были заданы две группы вопросов:

    1. Касающиеся основных направлений работ.

    2. Содержащие конкретные физические данные и константы.

    Определенные ответы БОР дал по первой группе вопросов. БОР дал категорический ответ на вопрос о применяемых в США методах получения урана-235, что вполне удовлетворило члена-корреспондента Академии наук проф. КИКОИНА, поставившего этот вопрос.

    Нильс БОР сделал важное замечание, касающееся эффективности использования урана в атомной бомбе. Это замечание должно быть подвергнуто теоретическому анализу, который следует поручить профессорам ЛАНДАУ, MIGDAL и ПОМЕРАНЧУК.

    Академик КУРЧАТОВ.
    Декабрь 1945 года.



Atomic Editorial Cartoons (August 1945)

Friday, June 29th, 2012

The American public reaction to the first atomic bombs was a mixture of exaltation and ambivalence — a relief that science appeared to be a possible deus ex machina that would end the terrible war, an ambivalence about the question as to the morality of the weapon and its implications for what wars in the future would look like. Spencer Weart's Rise of Nuclear Fear does a great job of talking about that ambivalence, as does the work of the late Paul S. Boyer, By the Bomb's Early Light.

There are lots of ways to probe that ambivalence. One interesting way is through the genre of editorial cartoons, which can boil down popular political opinions quite succinctly. I've used ProQuest to conjure up quite a few cartoons from August 1945, looking at the holdings of the Atlanta Constitution, Chicago Tribune, Los Angeles Times, and the New York Times.

There aren't as many as you might think — just a little over twenty total for those four papers. Here are a few of the most interesting ones, in order of date.

August 7

Los Angeles Times, August 7, 1945

This was the first one I found. Not a whole lot of content here other than the obvious excitement at the idea of a weapon of such tremendous power. Interesting that the clock motif dates from so early!

August 8

Atlanta Constitution, August 8, 1945

This one is fairly well-known — it makes quite a lot of light out of killing a lot of Japanese. Again, exhaultation and exuberance.

Chicago Tribune, August 8, 1945

The Chicago Tribune produced quite a number of these cartoons, and theirs were often pretty explicitly racist. This one also goes a bit beyond the other two so far in that it's actually making an argument: the bombs were justified because of Pearl Harbor. To consider the bombs in need of justification of this sort, even at this early stage, is a nice sign of the aforementioned ambivalence.

Chicago Tribune, August 8, 1945

Another from the Chicago Tribune, this one more explicitly ambivalent about what the bomb means for the future. Gotta love the depiction of the long-haired scientist...

August 9

Chicago Tribune, August 9, 1945

Hoo-boy — a lot of cultural baggage here! It's easy to mock the "magic electron" bit, but more reflectively, it's a sign at how brand-new the scientific terminology would have been to your average journalist, much less layperson. Some information on the science of the bomb had been released to the media this point in conjunction with the publicity efforts, but this is still well before the Smyth Report was released, so some scientific illiteracy isn't too surprising.

Los Angeles Times, August 9, 1945

The only cartoon I found which makes any reference to the Soviet invasion of Manchuria, which begun on August 9 (the same day as Nagasaki).

August 10

Los Angeles Times, August 10, 1945

Another exultant — and racist — cartoon.

August 11

Chicago Tribune, August 11, 1945

Another science-themed cartoon (from the same artist as the earlier one), but this time a lot less ambivalent.

August 12, 1945

Chicago Tribune, August 12, 1945

Ah, now here's some of the hard-core ambivalence setting in. Will the crater of the first atomic bomb be the grave of "warfare" or of "civilization"? Note this is the first one with any kind of mushroom cloud, as well. The Smyth Report had been made available to the press on the evening of August 11 (for release on August 12), so it's possible that the author here had access to slightly more detailed materials on the subject than those previously.

Newark Evening News, reprinted in the New York Times, August 12, 1945

New York Times, August 12, 1945

St. Louis Post-Dispatch, reprinted in the New York Times, August 12, 1945

On August 12, the New York Times print three comics on the subject of the bomb, at least two of which were originally printed elsewhere. The first is mostly positive — the atom will end war. The second is far ambivalent — humanity is but an infant preparing to play with life and death. And the third is, in my reading anyway, hard to parse. Is the new era a good thing? I'm not really sure how to interpret a giant hand jamming a lightning bolts into the planet — a good thing? A bad thing? A very awkward metaphor?

Chicago Tribune, August 12, 1945

This one is just... very odd. I guess it is supposed to be the Japanese Army using Hirohito as its face-saving surrender, because of the bomb? Hm. Not exactly a well-executed message in my view. But check out that dove with an atom bomb strapped to it:

That's wild.

August 13

Chicago Tribune, August 13, 1945

One thing to note with both this and the most recent comic is their confidence that the war would be ending soon. This was still a few days before the Japanese capitulation — which was not entirely expected. One wonders how the view of the bomb would have changed if Japan hadn't surrendered and the invasion had begun as planned.

August 14

Chicago Tribune, August 14, 1945

Another justifying cartoon from the Chicago Tribune. I've gotta say — I feel a little sorry for Japan in this one. I think the cartoon unintentionally makes them look like the underdogs.

There are a few more in here that I'm skipping, just for space and because they weren't that interesting. The next one sums up the message of quite a few of them:

Atlanta Constitution, August 20, 1945

Now we've really entered into the hand-wringing, what-about-the-UN, can-we-have-atomic-peace stage of things. Clichés abound.

And thus we slide — from the exultation of the bomb towards the "what next?" phase of things. The connection between the explicit racism and the heavy exultation isn't one that I'd really noticed quite so vividly before — it's the sort of thing that might be read between the lines of written articles or editorials, but becomes quite obvious when it is being illustrated.

I want to add just one more cartoon here — one which is only tangentially related to the bomb:

Chicago Tribune, August 24, 1945

One could make the argument that this connection between pesticides and WMDs is non-coincidental (the connection between chemical warfare and pesticides is pretty clear-cut), but what I find striking about this particular cartoon is the fact that in many ways it is deeper than it intended to be. Just like the atomic bomb, DDT was initially celebrated by many (most?) — but we've now replaced that excitation with at the very least ambivalence, if not abhorrence.


The Censored Chapter (1946)

Wednesday, May 2nd, 2012

An article of mine ("A Tale of Openness and Secrecy: The Philadelphia Story") has recently been published in Physics Today. Even better, the article has been made available for free on the Physics Today website (and as a PDF), so it can be read widely.

Click to go to the article online.

The basic story is thus: in late 1945, a group of scientists at the University of Pennsylvania, led by one William E. Stephens, decided that it would be a really cool thing to write their own, heavily-technical version of the Smyth Report. They would show that a bunch of non-nuclear physicists could, from the published literature and first principles, explain in technical terms exactly how atomic bombs worked. By publishing this, they'd prove that there wasn't any "secret" to the atomic bomb at all. But what started out as a statement about the futility of scientific secrecy quickly became a test of the limits of free discourse in the nuclear age.

These scientists were the unheralded predecessors of the Howard Morlands, Chuck Hansens, Carey Sublettes, and John Coster-Mullens of the world, but their story is basically unknown today, despite having lasting effects on the way that the postwar Manhattan Project and Atomic Energy Commission thought about secrecy. Their original goal — to show that clever outsiders could guess at secret things — definitely came across to the atomic officials, even if their denunciation of secrecy did not.

The final book was published as Nuclear Fission and Atomic Energy in late 1948 (two years after it was first written), and is now completely out of copyright. It's not an interesting read, on the whole, though the forward and preface are interesting in respect to the purpose of the volume.

But the published version is missing part of the chapter on nuclear weapon design — the part that was "voluntarily" censored at the request of the Manhattan Project and AEC. The reason it was censored was because the scientists had managed to independently derive the idea of implosion. The implosion design (which was used in the Trinity "gadget" and the Fat Man bomb) was still considered secret at the time (it wasn't declassified until 1951), so this was a pretty big coup on their part.

This week's document is a true exclusive: the censored chapter from Nuclear Fission and Atomic Energy, taken from the AEC's files. Stuck into the chapter was a note by William Waymack to Robert Bacher (AEC Commissioners both) decrying how irresponsible they felt the scientists were. (It is quoted, and partially photographed, in the Physics Today article.)1

Click the image for the PDF.

Everything from section 11.6 onward was cut from the final book (as can be seen from the version of the book, linked to above). It's the only part of the volume that was so censored, but it ends the chapter quite abruptly. I've marked the point of censorship in the PDF above.

It's not a thrilling read — it is heavy on the math — except for the fact in that it actually talks about implosion (by name!) which is pretty big bananas for a bunch of scientists with no Manhattan Project connection in late 1945. The fact that they mentioned it by name was considered a particular indictment by MED and AEC officials — though they pointed out that it was a common technical term and was present in every decent dictionary.

The fateful word.

If there are any technical people reading, I'd love to know what you think about their reasoning here. I suspect it is actually not that great — that other than getting the general implosion concept, it is probably more revealing of their ignorance than their knowledge — but I'm not a technical person, so I don't really know. My feeling is that while the point that trained scientists can independent re-derive and re-discover scientific "secrets" is largely correct, you probably can't do it very well from a purely theoretical standpoint. (To their credit, the physicists admit this, especially when talking about critical mass estimates, since they could tell from the Smyth Report that so much hinged on getting very good neutron cross-section measurements.)

Some parting intrigue: the Library of Congress has a copy of this early draft as well in its main holdings... but  somebody has long since torn out the pages in question. Spooky! I suspect the FBI — they were sent around in 1948 to round up any missing copies of the book, and the AEC had been told about the copies on deposit at the LOC — but I've no hard evidence on it.

An addendum: Yesterday evening, I received an e-mail from William Stephens' son, thanking me for writing the article. He added a detail I hadn't any clue about. At one point in the story, the Pennsylvania scientists go to New York to give a press conference denouncing atomic secrecy. Stephens' son was born while he was away — on the same day. I love that detail; it adds a personal touch to a story which is otherwise composed of letters and memos. (Look for some more thoughts along those lines on Friday.)

  1. Citation: Chapter 11 from William E. Stephens, ed., Nuclear Fission and Atomic Energy (draft June 1946), copy in Records of the Atomic Energy Commission, RG 326, National Archives and Records Administration, Records of the Commissioners, Office Files of Robert F. Bacher, Subject File, 1947-1949, Box 3, Folder "Philadelphia Story." []