“How much does that thing weigh?” Zak called.
“Plenty.” These were the strongest fields one could get and they were barely moving the object.
She trimmed the upper fields slightly. The sphere bobbed into the space between the permanent magnet’s poles—and stopped.
She carefully let her breath out, as if the slightest breeze might upset things. “Okay, I think we’ve got it.”
“Think this’ll hold?” Zak wore a worried frown.
“That’s a half Tesla field between the poles. It can hold plenty.”
The sphere hung still between the poles when Zak delicately raised the hoist. Slowly he lifted it to the ceiling. Alicia came over to the control panel.
“Careful now,” she said, taking over. She couldn’t leave the tricky part to him. If anything went wrong, it should be on her shoulders.
Servos whined as the hoist pulled back, running on rail lines back into the recesses of the big concrete walls. It carried the U-shaped magnet into the shadows.
Zak nodded. “Neat idea, getting it out of the way like that. Where in hell did that thing come from? Some part of the mechanical assembly?”
She realized that he thought the sphere was simply a big, shiny ball bearing. “I dunno. Best to get it out of the way of the crew, so they can seal the beam line.”
“Hope we can get back online soon.”
“Zak, the Core Element is beyond hope.”
“I know, I know, but the other detectors…”
His voice trailed off. He was still dazed. Had it been cruel to hustle him into action, set him to wheeling out the permanent magnet? No—she was sure the best way to absorb a shocking disappointment like this was to work on through it.
She clapped him on the shoulder. “There’ll be plenty of data from the rest of BRAHMS.”
“Think so? The midrapidity spectrometer—”
“Sho ‘nuff.” Her fake Southern accent always made him smile, like a private joke between them. “Let’s roll.”
By the time the work crew came back from lunch, she had a makeshift pressure patch on the beam line. This they didn’t like; repairs were their province. Alicia had counted on that to direct their attention away from the tarp she had thrown over the permanent magnet, stuck back into the wall recesses.
Maybe Zak was right, the thing was just some oddly blown bubble—but she didn’t think so. Her gut instinct was that the shiny ball was something utterly unexpected. Until she had a chance to study it, best not get the staff involved in the riddle.
So what could it be? An accident, but of what kind? Something in the experiment had made a metal sphere form? Blow up a panel or something, like a balloon? Not likely. Who said it was metal? A conductor, sure, or the magnetic fields couldn’t hold it. Shiny, yes—but the fizzing light was a powerful clue that something else was at work here.
From the trash heap of theoretical physics she knew plenty of hypothetical particles. Some were too bizarre to decay into everyday particles, so they might hang around—but as shiny bowling balls?
7
That night she lay awake and wondered why she had done it.
The sphere was plainly connected to the vacuum failure. When the crew had returned, there had been plenty of cleanup, and a lot of worried BRAHMS physicists turned up to survey the damage. She had hovered nervously, worrying that someone would spot the tarp and say, “Hey, what’s that?” But no one did. There was plenty of scenic wreckage to catch the eye.
Her snap diagnosis had proved right. The UC–Irvine Core Element had absorbed the momentum of the splintering beam pipe. Designed especially to look at uranium by-products, its layers of silicon were riddled with steel fragments. Gray shards like sharp sand lay everywhere. Building a second one from scratch would take many tedious months. And money. At least they had ample backup silicon sheets, so the cost would not be huge.
Nobody had any plausible ideas about what caused the explosion. Typical vacuum failures came from tiny cracks or badly fitted seals. Even a complete collapse sucked components inward, not out. Yet the interior beam pipe was bare of steel slivers.
The sphere had to be the answer. And she was concealing it.
Well, she thought grimly, it was her detector that had paid the price.
And her guest user contract covered data about microscopic particles, not macroscopic ones.
And… She grimaced in the dark and abruptly laughed at herself. “Face it, girl, you wanted the damn thing,” she told the darkness.
If this was a mere oddity, fine. If it was something fundamental, then she wanted to know what it was first. In her gut she knew it was that burning curiosity, not the ambition stuff.
There were four basic reasons why physicists did experiments, her thesis professor had once told her, and the list had remained chiseled in her memory.
First came I want to know. Her driver now. Prying into Mother Nature’s secrets. Well, the old Mother had made it hard to ignore.
Next came Theory predicts. The committees who approved beamtime applications liked that one. Experimenters awed by theorists felt it was the best reason of all. Alicia wasn’t one of those.
Among the older experimenters there was a lot of This is what I do. Habit, often rather mindless. More deeply, it meant This is who I am.
And another, one that had drawn her into using uranium: A sweet experiment. Maybe the best of all reasons. If uranium worked out, it could give them a key to the early universe. She liked the weird symmetry of using the element that had ushered in nuclear destruction to open the central mysteries of Creation itself.
The sphere might turn out to be sweet, too. She itched to find out. Alicia sighed and banished her doubts. She had acted on impulse, tucked it away—so be it.
Knowing that, what next?
The BRAHMS group was small in comparison with the big PHENIX machine, over which several hundred Ph.D. physicists labored. Still, “small” in the congested sociology of particle/nuclear physics meant that even BRAHMS had over thirty physicists contributing, from Strasbourg, New York University, Texas A & M, UC–Berkeley, and the Chinese Institute of Atomic Energy in Beijing. They all had been very sympathetic about the accident, tut-tutting at the shattered Core Element.
But they had been restless to clean up and get running again. The big detectors, PHENIX and STAR, lay in other bays around the racetrack. At the moment they were staged down for some repairs, but quite quickly they could make detailed studies of debris trajectories coming out of the uranium collisions. They could yield data—for those groups, not hers. The Core Element had been the leading instrument for this run and now it was down, like an injured horse while the race goes on.
Uptime, downtime, beamtime—these were the currency of particle physics power. In six days the Collider would switch back to throwing gold and the teams of detector tenders would change. This gang wanted all the data they could get. Too bad about the Core Element, but there it was.
“And the bastards are going to keep the data—my data—for months, too,” she said aloud into the darkness. “Damn!”
She let herself feel the anger and then managed to get a grip on it. She told herself the usual homilies. Their goals were hers, after all. Uranium might yet whisper wonderful secrets, if you cupped your ear just right.
She knew with a leaden certainty that revealing the sphere would conjure up the competitive rat race that she so disliked about the field already. Standing in line for her own data! In this era of few big machine facilities and squeezed beamtime, the merest odd spike in a graphed plot could bring about a feeding frenzy. “Gang-bang the data,” she sighed to herself.
Ah yes, the data, she recalled. They had waited until the last minute to tell her that she wasn’t going to get to crunch the data herself. Instead, they’d savor it at their leisure, here at Brookhaven. Anything really startling, they’d thoroughly chew through first.
Well, she thought vengefully, this was tit for tat, then. She wasn’t just saying, Okay
, then I’ll take my ball and go home.
She immediately felt a pang of remorse. This wasn’t going to sit squarely with her own inner voice and she knew it.
Still, what was it her father used to say? Into the gloom of the small Lab guest room she recited, “If you keep your eye on your goals, you’re not keeping it on your ass.”
8
The prep area was too damn busy. That became obvious in the first hour.
With the help of Zak and Brad Douglas, she had gotten the U-magnet lowered onto a motorized cart, then hauled it out to the prep area. Zak had already told Brad that they had found “something funny” in the beam pipe and that Alicia wanted to study it a bit. With solid Middle America good looks, Brad was a quietly ambitious student, even more awed than Zak by Brookhaven’s high-powered atmosphere. He had a way of working in sudden bursts of energy, as if an idea had caught fire inside. He respected Zak’s professionalism, with a hint of envy.
There was no immediate need to tell Brad anything and Zak’s dedication would keep him from mentioning the sphere to anyone. That would buy the time she needed.
She sent both of them off to help with the new start-up. The beam pipe section was replaced, the vacuum pumped down, and the BRAHMS group was starting up the uranium flux again. She should be in the control room to see the data come in again; she was still a team member, after all. At 10 A.M. the accelerator managers had started stacking uranium bunches into the RHIC ring again. Physics goes on. With the Core Element dead, she felt none of yesterday’s zest.
A look around; nobody watching. Gingerly, she pulled the tarp away from the magnet poles and examined the sphere. It reflected the hard ceramic fluorescent lights of the big prep room and Alicia’s squinty-eyed face, peering at it from two feet away. No radioactivity. The apparently smooth face of it had a slight blue tinge.
Alicia sniffed. Ozone? Could be the spark gaps firing nearby on a test rig.
She prodded it with a two-by-four, just like yesterday, with the same result: a hard surface, no give. She rapped it hard. No ringing, just a thump as it absorbed the impact. Solid?
Quickly she glanced around again. Good. No one seemed to pay her any attention. She studied the end of the two-by-four. A small dent, no other sign.
Her nerves jumped, fingers fidgeted. What more could she do here? Teams were busily checking out their gear all around her.
Physics prided itself on its international nature, but often it split into microscopic tribes. At Brookhaven each detector group had its own coffee urn; when one was “down,” they would not borrow coffee from another group, just grumble and wait for the repair. Alicia got around the Lab more than most, since the switch to uranium from gold affected every part of the Collider. More than once, people would ask her how things were going in the other groups, if there was any news—even though they were only a few hundred meters away.
Now physicists and technicians from several groups, the STAR and PHENIX and PHOBOS detectors, came around to offer commiseration for the loss of the Core Element: “A real puzzle, it is,” and “What you figure could do that, eh?” and the usual sympathetic noises. She nodded. They really were kind, but she had trouble concentrating on what they were saying.
She sighed. There were too many people around here to set up any diagnostics without arousing interest. And which diagnostics were relevant? She needed to get this thing into a quiet lab where she could think. Brookhaven was a particle factory, not a place for scrutiny.
Maybe we’ve discovered a really big particle, she thought crazily, the bigon. A particle the size of your head—no messing around with complicated microchips and imagers, just study it up close, by hand.
Physics had been like that just a century or two ago. Hertz measuring his waves by walking across his lab, because their wavelengths were as long as his arm. Roentgen discovering X rays using ordinary photographic plates and a steel paperweight. Maybe particle physics needed a bigon.
“Hope that field can hold on to it,” Zak said over her shoulder.
“Uh, how is the run going?” The rest of BRAHMS was still functional; the Core Element had been a special device custom-built for uranium.
“They’re getting plenty of events in the midrapidity arm.”
“Great.” They had spent the previous afternoon pulling the remnants of the Core Element out of BRAHMS. They would have to be content with the few hours of data they had on disk, analyzing the compact clouds of subnuclear debris, in the months it would take to rebuild the detector.
“That’s what, a half Tesla field in there?” Zak checked the side stenciling of the permanent magnet. “Yeah. Hope it’s enough.”
“To hold that sphere? Let’s see…” She wrote quickly on her clipboard. The flux of magnetic field crossing the sphere, multiplied by the sphere’s cross section area, had to exceed the acceleration of gravity, so… “As long as it’s less than a hundred kilograms, no problem.”
“For steel, that’s probably okay.”
“It’s holding steady,” she said. Let him think it was steel.
Zak wrinkled his nose. “What’s that I smell?”
“Ozone from those spark gaps over there, I think.”
“Ummm. Say, you get the word on that safety board hearing?”
She froze. “Uh, no. When?”
He glanced at his wristwatch. “In ‘bout two hours. Didn’t you check your e-mail?”
The section of ruptured beam pipe sat on the table between her and Zak and the safety board. The ceramic fluorescent clarity of the conference room gave the torn steel the air of a cadaver laid out for an autopsy.
The preliminaries were methodical. Description of procedures, review of evidence, plenty of Cover Your Ass detail. Her stomach lurched, but she did not give way to the usual impulses of insecurity, especially her specialty, talking too much. If only nobody had noticed the sphere…
The TV monitoring cameras had views partly obstructed by detectors but showed the pipe blowing in one blurred frame, Zak’s shirt visible in the distance. Alicia felt an undertone of uneasiness; engineers never liked the unexplained, whereas physicists lived for it.
Minutes tiptoed by, frowning. Hugh Alcott went over the facts in a monotone. “Note clear signs of a pressure rupture at segment 148. Some burnishing of the inner lining, as if from photon damage. Dave?”
Nodding, Dave Rucker gave her a wobbly, rueful smile. “I saw the mess it made of the Core Element. Sorry, Alicia, but I believe I can assure you and your team that this was not due to any foreseeable Lab oversight.”
She said, “The natural place to rupture was the focus, since the beam pipe is thinnest there. Some anomalous energy deposition in the pipe wall created a fracture, I suppose.”
The engineers had already thought of that, she was sure. A thin pipe let the decay products through well, but that carried a price.
“We’ve never had anything remotely resembling this,” Dave continued. “Clearly, some energy release created a pressure on the inner lining.”
“I understand,” she said.
“Point is,” Hugh said, knitting his fingers together, “did this happen because of something specific to using uranium?”
“I can’t imagine how.” She spread her hands. “It’s true the total energy released in a collision is higher, over 200 GeV per nucleon times 238, and times 2 because there are two nuclei. But that’s not a lot more than we had with gold.”
“Unless you crossed some crucial threshold,” Dave Rucker said quietly.
She was ready for that. “This is my postdoc, Zak Nguyen. He and I checked the signatures in the Core Element and the surrounding BRAHMS detectors. We looked at the count rates in the time just before we shut down. Show them, Zak.”
Zak rose and handed out copies of an energy graph. He was grinning to cover his nervousness, she saw. He gave the specs and described methods in a flat, small voice that got stronger as he got into the detail. “These show no unexpected excess in counts in any detector,” Zak conc
luded firmly.
“Ummm.” Dave pointed to a descending curve. “Looks like the base rate was low already.”
“We had a slow erosion of flux for several hours before the incident,” Alicia said. “The system was underperforming.”
Hugh Alcott looked attentive. “You’re suggesting a system failure?”
Alicia shrugged. “I’m not a Collider expert.”
“It’s worth checking into,” Dave said. “I’ll recommend a look-see to Tom Ludlam.”
Alicia nodded. Ludlam was the highly respected research director.
“Let me get this straight.” Hugh leaned forward. “You saw nothing else on the Core Element signal?”
“No, nothing.” Not her fault if they didn’t ask the right question.
“If this blowout had occurred at the focus of one of the big detectors, PHENIX or STAR,” Dave said in a slow, troubled monotone, “we’d have a catastrophe. It would’ve peppered all the microcircuitry and made the detectors useless.”
“Scary.” Hugh nodded. “I’m still not convinced this hasn’t got anything to do with using uranium.”
Alicia had nothing to add to that. She watched the board and waited. As a graduate student she had learned that among physicists, unless you were pretty damn sure of what you said, best not say it.
Dave said soberly, “Until we figure out what happened, I think we’d better not do any more uranium experiments, Alicia.”
She had expected this. If they found nothing, a few months of frustration would make the whole matter recede. By that time she would know what had happened and could make her pitch for resumption of uranium runs. “I understand,” she said.
Dave’s lips parted a bit, as if he were surprised. The confrontational style of the field virtually dictated that an adverse ruling be argued against and then appealed. Her simple acceptance would probably work better, she calculated. When she came back with an explanation and cure, they would be better disposed to go along with her.
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