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  The discovery thrilled physicists around the world, not least Marie Curie, to whose deathbed the Joliots brought a test tube of the first artificially produced radioelement. “I can still see her taking [it] between her fingers, burnt and scarred by radium,” Joliot recounted later. “I shall never forget the intense expression of joy which seized her.”

  The Rad Lab received the news from Ernest Lawrence, who came “roaring into the lab . . . waving a copy of Comptes Rendus over his head,” as Livingston remembered the moment. The staff did not greet the Joliots’ achievement as joyously as Madame Curie, for the discovery was another reproach to their slapdash methodology. No laboratory in the world was as well equipped as theirs to discover artificial radioactivity, for none was as capable of such sustained bombardment. No lab had less excuse for overlooking a phenomenon that indeed had been in front of the scientists’ eyes for months. They had bombarded dozens of elements with deuterons and assiduously tracked emissions of alpha particles during the bombardments; but the continued emission of electrons or positrons after the bombardments ended had escaped their notice.

  It only added to their shame that they were able to reproduce the Joliots’ findings almost immediately with the cyclotron. The Joliots had hypothesized that the same radioactivity they had induced in boron with alpha particles would be produced by deuterons acting on carbon. Deuterons being the Rad Lab’s stock in trade, Lawrence commanded, “Let’s try it out.” It took only minutes for Livingston and Malcolm Henderson to discover the explanation for the lab’s failure to detect what the Joliots had found: the same switch operated the cyclotron’s oscillator and its Geiger counter, so that turning off the cyclotron also turned off the detection apparatus. Livingston and Henderson rewired the switch and trained the deuteron beam on a carbon target for a quarter of an hour. Then they activated the counter. “There it was: click, click, click, click, click, click,” Livingston recalled. They had transmuted carbon into radioactive nitrogen. “It was there waiting for us. In less than half an hour from the time Lawrence brought the news, we were observing it.”

  Lawrence camouflaged his frustration by ordering up a lab-wide effort to expand the Joliots’ findings beyond aluminum, magnesium, and boron to heavier elements. But he communicated his true feelings to his closest colleagues through a series of confessional letters. “We have had these radio active [sic] substances in our midst now for more than half a year,” he lamented to Joe Boyce at Princeton. “We have been kicking ourselves that we haven’t had the sense to notice.”

  Given the claims emanating from Berkeley about the superiority of the cyclotron for all varieties of nuclear research, the oversight demanded a deeper explanation than simply a miswired switch. One excuse Lawrence cited frequently was that induced radioactivity was so unexpected a phenomenon that the Rad Lab could not be blamed for missing it—every other physics lab in the world had missed it too, until the Joliots came upon it by accident. But this was not quite true. As early as the 1920s, Rutherford had started searching for induced radioactivity in targets blasted with alpha rays. He failed because his detection apparatus was not capable of sensing neutrons and positrons—that was an understandable oversight, for neither particle yet had been discovered. The unfortunate wiring of the cyclotron was hardly an excuse for the lab’s peculiar failure to search for evidence of a phenomenon that Rutherford had determined to be within bounds of theoretical possibility some fifteen years earlier.

  Lawrence remained defensive about the oversight as late as 1940, when he rationalized it as the consequence of the Rad Lab’s singular devotion to improving the cyclotron at the expense of unimportant short-term discoveries. The Joliots’ findings, he told the Rockefeller Foundation’s Warren Weaver, “would always be a matter of little more than academic interest as long as means were not available to produce these radioactive substances in enormously greater amounts.” Luckily for mankind, he suggested, the cyclotron had been painstakingly developed to the point that it could perform that service.

  The whole Rad Lab felt the disappointment keenly. “I always felt sorry we didn’t find artificial radioactivity for Ernest,” Henderson lamented years later. “It was in our hands. All I had to do was put the Geiger counter in and put it on target and I’d have had it.” Jack Livingood put Lawrence’s lament to Boyce in graphic terms that his mentor never would have used: “We felt like kicking each other’s butts.” The real culprit was the culture of the lab, as dictated by Lawrence. His preoccupation with improving the cyclotron condoned sloppy and inattentive experimental work.

  As it happened, the Joliots’ discovery of artificial radioactivity came at the moment when Lawrence was fighting his final rearguard action in defense of his deuteron theory. The dual embarrassments would have the mutually reinforcing effect of reorienting Ernest and his laboratory toward much more careful research. This happened just in time, for frustration over the lab’s focus on engineering was again on the rise. Franz Kurie, who had come to Berkeley from Yale as a National Research Council fellow, felt the Rad Lab’s experimental procedures were too slipshod to foster serious research on the cyclotron. At Berkeley, he told his Yale labmate Don Cooksey, “the field is getting messy . . . Ernest and Malcolm [Henderson] are too excited to go slowly. Their targets are dirty, and they refuse to take long counts.”

  An imaginative experimentalist who had been skeptical of Lawrence’s deuteron theory, Kurie proposed to Cooksey that they goad Yale into building a cyclotron to rival Berkeley’s—and to do better work. “I’m thoroughly sold on the cyclotron as the perfect high-voltage source,” he wrote, asserting that building one in New Haven would put Yale “on the map in nuclear physics” as a lab “probably second only to Ernest’s.” He added, with characteristic Eli hubris, that Lawrence himself would benefit from Yale’s implicit endorsement of his machine: at the moment, he advised Cooksey, “no one really believes his cyclotron works” due to the low quality of physics coming out of Berkeley. In the end, Cooksey chose the opposite course. A friend of Ernest’s since their days as graduate students together, he left Yale to join the Rad Lab, where he would play out his long career as Lawrence’s right-hand man.

  Despite Kurie’s doubts, signs already had emerged that tinkering was yielding to serious science in the Rad Lab. The deuteron was achieving its moment of glory, for the double-barreled particle proved much more useful than the proton in inducing radioactivity in light targets, as was discovered by lab members rushing to replicate the Joliots’ results at Lawrence’s command.

  The Rad Lab’s first report on its findings reached the Physical Review dated February 27—a crucial two days earlier than a letter from Lawrence’s Caltech rival, C. C. Lauritsen, documenting his own experiments. The communications, which appeared on adjoining pages of the Review’s March 15 issue, were notable for their divergent approaches to this important scientific effort. Lawrence’s brusque four-paragraph letter reported deuteron-induced radioactivity in fourteen light elements and speculated brashly that “in these nuclear reactions new radioactive isotopes of many of the elements might be formed.” By contrast, Lauritsen and his Caltech colleagues soberly devoted two full pages to a meticulous accounting of every step they had taken to validate the French findings on carbon and boron alone. They provided precise ionization data, spelled out their theory on how positrons emitted by the bombarded atoms transmuted into gamma rays, and carefully avoided any speculation about the significance of the new phenomenon. The difference was telling. Scientists seeking a step-by-step guide to the novel science of artificial radioactivity needed to study Lauritsen; those seeking a foreshadowing of the new science’s possible harvest consulted Lawrence.

  For all its audacity, Lawrence’s conjecture about the potential to create new radioisotopes was correct. The cyclotron started turning out these new products with amazing regularity. “To our surprise,” Lawrence reported to his old friend Joe Boyce, “we found that everything we bombarded with deuterons (about 12 of the elements) is rendered
radio active.” The cyclotron was about to secure an international reputation as an indispensable tool of nuclear science. Radioisotopes would be the currency of a new physics, chemistry, and biology, and Lawrence’s cyclotron would be the world’s preeminent mint. Within months, the deuteron fiasco would be forgotten, and universities across the nation and in Europe and Asia would be clamoring for their own machines.

  • • •

  One other discovery by a European laboratory would help to establish the cyclotron as a must-have apparatus for physics research. In March, Enrico Fermi demonstrated that neutrons were the most effective inducers of radioactivity in elements heavier than phosphorus. The finding enhanced the Italian physicist’s fame as that rare scientist equally adept at theory and experimentation, for it validated his own hypothesis that the chargeless neutron could penetrate heavy nuclei that repelled deuterons and other heavy, but charged, projectiles. His discovery also underscored the cyclotron’s utility as a prodigious manufacturer of protons, deuterons, and neutrons (which were generated by training the deuteron beam on a neutron emitter such as beryllium).

  The old guard’s natural radiation sources, the thimblefuls of radium and clumps of radium-beryllium they used to make the discoveries that transformed physics—nuclear disintegration, the neutron, and artificial radioactivity—had had their day. Radium had passed its prime as an experimental source, for in its natural form, it did not produce particles with the energies necessary for probing heavy nuclei. But the cyclotron could. Its day had arrived.

  At the Rad Lab, every researcher claimed or was assigned an element from the periodic table as an experimental target, with the most senior staffers getting the most promising substances. Martin Kamen, a postdoctoral chemistry fellow from the University of Chicago who showed up soon after the craze took hold and therefore had no seniority, scrounged among the heavy elements thallium and bismuth, which could not easily be activated even at the energies produced by the twenty-seven-inch cyclotron. But no one worked in solitude. With the team-style research encouraged by Lawrence reaching its full flower, collaboration was the order of the day. Kamen soon was drafted by the physicist Jackson Laslett to help with the chemical separation of sodium isotopes, and the chemist Glenn Seaborg was absorbed into a team working with uranium. Ernest presided happily over all this activity without bothering himself too much about the experimental results, notwithstanding the lesson of the deuteron fiasco. “We are having a merry time bombarding atoms,” he wrote Boyce. To Jesse Beams he added, “We are finding so many things happening when we bombard nuclei that we are rather bewildered.”

  The new paradigm of collaborative research pursued in the ramshackle Rad Lab surprised visitors bred in the insular working style still prevalent in academia. Among them was a graduate student from the University of Chicago named Luis Alvarez, a rail-thin, ruddy-faced young man with rust-colored hair, for his mother’s Irish genes had outdueled those of his paternal forebears from northern Spain. Luis’s fascination with the Rad Lab had been triggered by a lecture Lawrence had delivered at Chicago, and deepened when he accompanied his father, Walter, a distinguished physiologist at the Mayo Clinic, on a visit to Berkeley during the summer of 1934. Luis was disappointed by his first sight of the old wooden building with its peeling white paint; but what he discovered when he stepped over the threshold was “the most exciting place I had ever seen,” he would recall. Alvarez exploited his status as the scion of a prominent scientific family to haunt the place for several days, soaking up its unique atmosphere. Graduate students at Chicago, he observed later, “enjoyed a fine camaraderie in the halls . . . but it was considered a serious breach of etiquette for anyone to suggest how a friend’s experiment might be improved. By contrast, everyone at the Radiation Laboratory was encouraged to offer constructive criticism of the experiments his colleagues were performing.” At Chicago, the students hoarded their meager supplies of chemical reagents and worked behind closed doors. But there were no doors inside the Rad Lab. “Its central focus was the cyclotron, on which everyone worked and which belonged to everyone equally (though perhaps more than equally to Ernest) . . . Everyone was free to borrow or use everyone else’s equipment or, more commonly, to plan a joint experiment.” The team approach to physics, Alvarez judged, was “Lawrence’s greatest invention.” Alvarez was determined to become part of it as soon as he received his degree.

  What he had witnessed was the harvesting of the twenty-seven-inch cyclotron’s copious output of deuterons and neutrons. The stepped-up bombardments ordered by Lawrence coincided, fortuitously, with an improvement of the twenty-seven-inch vacuum chamber by Don Cooksey, who was filling the vacuum in the engineering staff created by the departure of Stan Livingston for a job at Cornell. (Cooksey would relocate for good the following year.) His redesigned tank nearly doubled the energies produced by the cyclotron to 6 million volts and quadrupled the current.

  The lab was swimming in a sea of subatomic projectiles. Fermi’s associate Franco Rasetti came away from a brief visit in 1935 astonished at the “enormous superiority” of the twenty-seven-inch cyclotron for the production of neutrons, far beyond anything available in Europe. Fermi had conducted his experiments with a 1-gram vial of radium that produced 630 millicuries of radiation, generating about 630,000 neutrons per second; Rasetti calculated that the cyclotron’s deuteron beam was throwing off 10 billion neutrons a second, or the equivalent of several pounds of radium.I Around that time, Berkeley’s publicity department (assisted by the Rad Lab’s Paul Aebersold) estimated that the cyclotron, which cost less than $100,000, had produced “radiation equal to $5,000,000 of radium.” The equation involved a certain amount of fanciful math, but there was no disputing that the cyclotron was beginning to pay its way as a producer of radioactive isotopes on an industrial scale.

  Nor was the fund-raising potential of the cyclotron lost on Lawrence. Its initial radioactive products were suited best for physics research, but that was only a start. Wealthy research foundations were especially interested in isotopes for medical research and cancer treatment. The characteristics of a useful biomedical isotope were well understood: they needed to have half-lives of several hours at least, be nontoxic to humans, and vigorously emit gamma rays to replicate, or preferably improve upon, the physiological effect of radium on cancerous tumors. The pinch of the Depression forced many research philanthropies to reduce their grants for basic science in physics and chemistry, but money still flowed abundantly for projects in biology and medicine.

  Lawrence tailored his research program and his fund-raising campaign accordingly. “We are now well on the road to the production of neutron radiation of great intensity and are approaching the biologically interesting domain,” he informed Ludwig Kast, president of the Josiah Macy Jr. Foundation, which supported health research exclusively. Artfully, he implied that artificial radioactivity, especially as induced by neutrons, had been a discovery of the Rad Lab: “In my last letter I reported the discovery of radioactivity artificially induced in many common substances by bombardment of high-speed deutons . . . During the past two weeks we have found that an analogous effect is produced by neutron rays.” This rather deliberate elision of Fermi’s role in neutron research was the prelude to a pitch for $2,250 “to increase the yield of neutron radiation tenfold or more.” He got the grant, and another $5,000 from the ever-faithful Research Corporation, to work toward the large-scale production of isotopes.

  It was not long before he found the medical radioisotope of his dreams. It was sodium-24, produced by the bombardment of ordinary rock salt by deuterons. Radio-sodium had a gratifyingly lengthy half-life of fifteen and a half hours and gamma ray energies that Ernest calculated at about 5 million electron volts. That made the substance much more potent than radium and therefore useful for physics and medical research alike. It was a solid result, which Lawrence announced promptly with a brief letter to the Physical Review, followed by a lengthy report in which he left nothing to chance, describing his me
thodology in painstaking detail and accounting for the possibility of contamination; he was determined not to repeat the deuton fiasco. “Doubtless radio-sodium will find many uses in the physical and biological sciences,” he reported, for once without exaggeration. The new isotope’s potency and the efficiency of the cyclotron in producing it surprised even experts accustomed to Lawrence’s guileless optimism. When he informed Fermi by letter that his machine had produced a millicurie of radioactive sodium, Fermi scoffed. He assumed that Lawrence, in his slapdash way with numbers, had mislaid a decimal point and meant a microcurie, a thousand times less. When he “tactfully” corrected Lawrence by return mail, Lawrence replied with a letter in which was enclosed, sure enough, a millicurie of Na-24. Only a few months earlier, such an enclosure would have been precious almost beyond measure. Now it could be dispatched by mail to silence a doubter.

  The obvious value of radio-sodium in scientific research and commercial applications led to a new dialogue between Lawrence and the patent office, more prolonged and rather less rewarding than the process that had led to the cyclotron patent. This time Lawrence launched the patent frenzy himself. A few days after the first production of radio-sodium, he mentioned the achievement to Arthur Knight, the Research Corporation’s patent lawyer, proposing that an application be prepared immediately for patents on both the isotope and its method of production. Time was of the essence, he told Howard Poillon at Research Corporation headquarters, for the application had to be filed “before the accompanying announcement appears in print, October 15, thereby keeping open the possibility of patent applications in foreign countries . . . Radio-sodium is destined to be of practical importance.”