The Telescope in the Ice

by Mark Bowen

  * * *

  The scientific legacy of the Hawaii workshop is carried on today by numerous experiments around the world, and two Nobel Prizes have so far resulted. However, its most important legacy is probably the vast network of connections it spawned among people and nations. The Soviet presence was especially meaningful. In a concluding resolution, the conferees proclaimed their collective view of “DUMAND as a vehicle most appropriate to collaboration on the peaceful exploration of this scientific frontier by interested scientists throughout the world.”

  This in spite of the numerous “spooks” from both sides of the Iron Curtain who lurked in the background at the workshop. Since the scientists refused to take them seriously, however, their presence only added to the sense of international camaraderie. John Learned remembers an amusing vignette involving the erudite Russian theorist Veniamin Berezinsky:

  “There were some Russia-watchers, U.S. Navy people, as ever there were at those sorts of meetings, and Venya was chairman of one of the sessions. Having a Russian chairman was a big deal. He spoke quite good English and read English and read English literature and so on, was clearly much more cultured than the party apparatchik who was along. So Venya stands up to chair his first session, and he says, [fake Russian accent] ‘Okay, now you have Russian chairman, the meeting will run on time. And remember, Big Brother is watching you!’ And we all go ‘What?!’ Later we took him aside, saying, ‘Ven, where did you get that line?’ He said, ‘Oh, I read Orwell, of course.’ We said, ‘Ah, this book you can get in Russia?’ He said, ‘No. No.’ So that was great fun. And then there was clearly a KGB guy along who was taking pictures of everything and so on.”

  On the American side, they had Peter Kotzer and his friends.

  Right around the time of this meeting, Fred Reines, who had now moved from Case to the newly established Irvine campus of the University of California, offered John Learned a position as a visiting scientist in his group.

  Neutrino astronomy was off and running.

  * * *

  The friendships born in Hawaii were cemented in several more gatherings over the next few years. There were meetings at the Scripps Institution of Oceanography in La Jolla, California, and in Moscow, where the Russians expressed a strong interest in collaborating and offered “several thousand phototubes for DUMAND,” an outlay that would have cost about $10 million in the west.

  The Institute for Nuclear Research of the Soviet Academy of Sciences had been pursuing its own program of natural neutrino detection since the early sixties, and none other than Moiseĭ Markov, a senior member of the academy, had been directing it. The Russians already had two neutrino detectors running deep in a tungsten mine in the Baksan Valley in the northern Caucasus, one employing scintillation à la Cowan and Reines and the other the radiochemical method of Pontecorvo and Davis. In 1977, Markov chaired an international neutrino meeting at this laboratory, which occasioned an unauthorized and unsuccessful attempt to climb nearby Mt. Elbrus, the highest mountain in Europe, by John Learned and Dave Schramm. (We won’t go there.)

  But the most memorable of the early meetings took place in 1979 in the Russian far east, where the hosts had a location of their own in mind that had a different ambience altogether from Hawaii and combined both water and ice.

  It had been identified by Aleksandr Chudakov, yet another Russian who had realized the potential of underwater Cherenkov detection in the fifties. Shortly after returning from Hawaii, he proposed a telescope of the Markov variety in the waters of Lake Baikal, the largest, deepest, and probably oldest freshwater lake in the world.

  Baikal lies in a rift in the Eurasian tectonic plate that formed about twenty-five million years ago. It is crescent-shaped, four hundred miles long, an average of fifty miles wide, and in some places over a mile deep. Comprising about 20 percent of the Earth’s liquid freshwater, it supports one of the most diverse assortments of aquatic life of any lake in the world, including the only known freshwater seal. In 1996, the United Nations listed it as a World Heritage Site, giving it the protective status of the Grand Canyon or Australia’s Great Barrier Reef.

  Relevant to a neutrino telescope, Baikal’s waters are exceptionally clear and unpolluted, and its surface freezes in winter. It seems that Chudakov was first to realize that this seasonal covering would provide a convenient natural platform for the deployment of a neutrino telescope on the bottom of the lake. This sort of pragmatism and attention to the art has characterized the Russian branch of this business all along.

  The 1979 Pacific Science Congress, a meeting encompassing many disciplines that had been held since the 1920s, took place in Khabarovsk, the second-largest city in eastern Russia. The DUMANDees joined everyone else there, and then shifted more than a thousand miles northwest to hold their own meeting at Baikal itself.

  Outwardly, it seemed that there could have been a serious clash of cultures. The Russians were exceedingly formal and hierarchical, and the Americans, especially this bunch, utterly egalitarian. But it seems that everyone saw past these differences and got along famously. The Russian delegation was led by Moiseĭ Markov, who was in his early seventies by this time and one of the most prominent scientists in the USSR. Aside from being a distinguished member of the Soviet Academy, he was Secretary of its Department for Nuclear Physics, which oversaw the entire Soviet effort in both accelerators and cosmic rays. Meanwhile, the Americans didn’t see any need for a leader at all until they found out that they had to have one in order to enter the country. They got together and asked Learned, who casually agreed.

  “In those days, I was wearing Levis and a Levi jacket and had a ponytail and, as usual, a beard, and looking like the revolutionary. And here’s this fine old silver-haired gentleman [Markov], who is dressed well. So I’m thinking, ‘Uh-oh, we’re probably not gonna hit it off.’ … It turns out he was the nicest, nicest gentleman, and he paid no attention to my uppity-ness.”

  John expressed his disapproval of the class separation in the Soviet system by resorting to various antics, such as riding in buses “with the people,” rather than joining Markov in his limousine, while his host responded with grace and tact and even, perhaps, quiet appreciation.

  Markov had two lieutenants in neutrino astronomy, both theorists (who, I am told, have never gotten along). One was his former student, Igor Zheleznykh, who had written the seminal doctoral thesis in the late 1950s and was a bit of a dabbler. The other was Grigorii Domogatsky, who had a longer attention span and was taking the lead on the Baikal project.

  Domogatsky seems to be the sole representative of the sciences in a well-known, highly cultured, upper-class Russian family, populated with artists of all kinds. He’s a down-to-earth, no-nonsense individual, who used to insist on keeping his desk in a busy office with the students and post-docs in his Moscow institute, so as not to lose touch with “real” physics. He met the tired western delegation when they arrived in Khabarovsk, late at night after the usual travel delays.

  “He was one of these guys who would smoke his cigarette held backwards, you know? Leather jacket and looking like a Soviet Mafioso for all the world,” says Learned. “So we meet him in the dark of the night in this hotel and he’s going around to each of us handing out stacks of rubles, because they gave you walking around money in those days; you couldn’t easily convert dollars to rubles. It was just a very strange scene, this strange Russian character handing out money to all the Americans in the dark of the night.”

  The physicists had a grand time in Khabarovsk—there was plenty of partying. And when they moved out to the lake, had a chance to have some fun at the expense of Peter Kotzer, the suspected spy, who had turned up uninvited.

  “The Russians said ‘What shall we do? We have to let him talk,’” Learned remembers. “I said, ‘Okay, fine, but I’m not going to attend.’ So they scheduled a trip out on a boat at the same time that Peter was going to talk. We all went out on the lake and drank vodka, and the crew got drunk and ran the ship up onto the
shore and smashed up the dock on the way back, and … anyway, lots of stories.”

  Another of Kotzer’s annoying habits was to add the other scientists’ names to his research proposals without telling them in advance. Eventually, he was drummed out of the corps.

  Fueled by such camaraderie and what seems to have been a good deal of alcohol, the science progressed famously. In 1979, a collaboration of institutions from the United States, Japan, Germany, and Switzerland submitted a successful proposal to the U.S. Department of Energy, and on the first day of 1980, the Hawaii DUMAND Center was established at the University of Hawaii. John Learned and Arthur Roberts moved to Honolulu to work full-time on the project, with John as technical director.

  * * *

  Synchronistically perhaps, Francis Halzen happened to visit Honolulu in the summer of 1980 to work on a problem involving quarks with fellow theorist Sandip Pakvasa. There were other Madisonians, past and present, in town, including Learned, of course, and Ugo Camerini, who was there to work on DUMAND. Joining them regularly for lunch, Francis began learning about the emerging field of neutrino astronomy. He still thought of particle physics as his “profession,” and says that no respectable particle physicist would have touched cosmic rays in those days. But he wasn’t overly concerned with that kind of respectability. He had dabbled in the field before, with Dave Cline, and now he began to move into it in a bigger way. Although he wasn’t aware of it at the time, there was a reason for this change in orientation, and he would discover the reason as a direct result, more or less, of his visit to Hawaii.

  The Hawaii physics department had figured out a creative way to fund Francis’s visit by asking him to teach what they represented as a “fake” weekly seminar. This seemed manageable, but when he showed up for the first class he found “the whole faculty … sitting there, heh, heh. So, ah, ‘What do I do now?’”

  Taking what he thought would be the path of least resistance, that is, work, he decided to review the current status of particle physics. But it turned out to be more work than he had imagined. As he proceeded to roll out the lectures, he realized that he was conducting this review at a critical moment. So many discoveries had taken place so rapidly over the previous decade that the particle physics community had not had a chance to assimilate them. “What I was about to do was to put a range of topics together which we now refer to as the standard model. It’s not like I invented the standard model—it was clear; it was obvious—but [this] had never been done.”

  When he returned to Wisconsin, Francis taught the course again mostly to faculty. Then he discovered that one of his longtime collaborators, Alan Martin from Durham, England, had taught a similar course over the same summer that he had, and done a better job of it, to his way of thinking. The two got together and collaborated on a textbook, Quarks and Leptons, which remains, thirty-five years later, the most popular introduction to graduate-level quantum mechanics in physics programs around the world. It has been translated into many languages.

  The book has never been updated, and there is a message in that. The sad fact is that it has not needed a second edition, for there have been no fundamental advances in particle physics since it was written. All the particles predicted by the standard model, except one, the Higgs boson, were discovered by the time the book was published.

  Halzen and Martin completed the final draft in Durham just before Christmas 1982. Francis then drove to Belgium, with the draft lying beside him on the passenger seat of his Volkswagen Sirocco, to spend the holiday with his family. After the holidays, he flew to Japan to start a fellowship at the University of Tokyo, and when he got off the plane he was told that Carlo Rubbia, Dave Cline, and their colleagues at CERN had discovered the W and Z weak intermediate bosons. (Halzen, Martin, and Vernon Barger had done some important phenomenological work to facilitate the discovery, and Rubbia went out of his way to acknowledge this work in his Nobel lecture.)

  The W and Z were the last undiscovered particles in the standard model, except the Higgs, and they—and the Higgs, too, for that matter—were already in the book.

  At the beginning of 1983, then, more than three decades ago, accelerator physicists realized that they were entering what they came to call “the desert”: the Higgs was the only likely discovery on the horizon, and it would require an accelerator orders of magnitude more powerful—and more expensive—than the one Rubbia had employed in winning CERN’s first Nobel Prize. An unhealthy competition developed between the U.S. and European physics communities. The former began designing the Superconducting Super Collider, which ended up as a $2 billion hole in the Texas prairie, while the latter, led by the newly beatified Rubbia, started in on the Large Hadron Collider. Rubbia’s original plan was to finish it in 1991. It went online about twenty years behind schedule.

  In the thirty-plus years since the W/Z discovery, the particle physics community has been searching desperately for experimental evidence of any kind of physics beyond the standard model. The most visible theoretical forays have been supersymmetry, which posits a heavy sister or brother for each of the particles in the model, and string theory, which makes few if any experimental predictions. Rubbia, Cline, and their friends were on the lookout for supersymmetric particles even in the early eighties as they searched for the W and the Z—indeed, they were more interested in supersymmetry than in the particles they ended up finding—but they came up empty-handed. So far, the operators of the LHC are coming up empty-handed as well. Their main hope, as it was for their predecessors more than thirty years ago, remains supersymmetry.

  While the discovery of the Higgs in 2012 was a tremendous triumph, as of this writing, nothing in its behavior or in any other data from the LHC has come as a surprise. It all conforms to the standard model. As Gary Taubes, the author of Nobel Dreams, wrote in 1986, “If there is in fact no life in the desert, no new particles, then there will be no more evidence forthcoming with which to build better theories. Progress will be at an end. The standard model will remain standard for the duration.”

  As I pointed out in the first chapter of this book, only one chink has so far been discovered in the armor of the standard model, and it has to do with the behavior of the neutrino. Moreover, it was discovered not by an accelerator, but by an underground neutrino detector in the mode of Greisen and UNDINE. More on that in a moment.

  * * *

  One of Francis Halzen’s nicknames is “the fastest pen in the west.” He made his first move into neutrino astronomy in his spare time during his 1980 visit to Hawaii by contributing a theory paper to a major DUMAND symposium that John Learned organized in Honolulu that summer (see photograph 1). The paper gave estimates for the number and energy spectrum of the muons that the proposed instrument might find in high-energy cosmic rays.

  Other theorists participated, including the leading Russians. One of Learned’s aims was to build interest in the community, and theoretical work related to an experiment generally helps with that. But John believes Francis gave DUMAND an especially strong shot in the arm not only with his phenomenological work, but also by including DUMAND in the many talks he gave as he resumed his extensive travel around the world. This is a form of scientific pollination, since one picks things up on these travels as well.

  “Francis would be absolutely scandalized if I made this analogy,” says Bob Morse, “but … Francis is our new Dave Cline. Dave used to go around and visit all these flowers and take that little pollen on his legs and deposit it here and there and let us know what was going on. Francis does that now.”

  * * *

  Unfortunately, the delicate shoot of Cold War cooperation that was just taking root in 1980 was swiftly yanked from the ground. In December 1979, less than a month before DUMAND was funded, the Soviets invaded Afghanistan, and in the U.S. presidential election that took place in November 1980, Jimmy Carter was replaced by the more confrontational Ronald Reagan. Arthur Roberts observes that “the severing of the Russian link was done with elegance and taste. We w
ere told, confidentially, that while we were perfectly free to choose our collaborators as we liked, if perchance they included Russians it would be found that no funding was available for us.”

  “We kept channels open and stayed friends, but we couldn’t work together,” adds Learned.

  This may have been a blessing in disguise for the Russians.

  6. Science at Its Best

  The DUMAND collaboration started off Thinking big. Too big, most likely. The original vision called for an array comprising 1.6 cubic kilometers, three miles deep in the Pacific Ocean, nineteen miles from the nearest shore. There would have been more than 1,200 “beaded strings,” holding 18 light detectors each, adding up to more than 23,000 detectors in all. Each bead would consist of a glass sphere capable of withstanding at least 500 times atmospheric pressure, encasing a photomultiplier tube and its associated electronics, and the phototubes alone would have cost $70 million. The strings were to be anchored to the ocean floor and held taut and upright by buoys at their tops. The collaboration planned to use fiber-optic cables to carry the electrical signals to shore, even though the technology had not been invented yet. Arthur Roberts observes that “the oceanographers were amazed—this project was larger than any other peacetime ocean project by a factor of the order of 100.”

  In the end, they never managed to place a single functioning string on the ocean floor. The first was lost in 1982 when the cable lowering it into the water broke, despite being rated at twenty times the actual load. This was eventually ascribed to “snap loading”: if the string was some distance down and the deployment vessel rose rapidly with an ocean swell, the string couldn’t follow because the bulbous optical modules would resist being dragged through the water in the manner of a sea anchor. A second string was lost in 1985, “when the explosive bolts, designed to release it after a planned sojourn on the ocean floor, failed to release when fired.”