And still the flowers bloomed.
She managed to spill champagne on her classic white lab coat, worn in self-mockery over jeans and a frumpy, oil-stained blouse. A standard radiation badge clung to the pocket. She thought abstractly that she had always felt a bit silly wearing it. If by some bizarre chance she were exposed to the beam while it was running, the badge-measured dosage would make an interesting notation on her tombstone.
Again she thanked all the people who had labored to make the shift from gold to uranium, who had kept the BRAHMS system working, the many expert hands it took to keep one of the most complicated machines in the world up and running. And she watched the screens, entranced.
“And Zak. C’mere, you.” She hugged him. “It’s not love that makes our world go round—it’s postdocs!”
Laughs, cheers. “And grad students,” she added, pounding her own grad student, Brad Douglas, on the back.
She remembered stories about the old bubble chamber detectors at Brookhaven. They were pressurized bottles where particles left bubble trails which cameras read by arc lamps. A famous story told how when a propane bottle exploded, the grad students fled. A postdoc realized he was going to lose his data and ran back inside. A second blast blew him out the door, data in hand. Nobody was surprised that he had gone back in.
“Data, gorgeous data.” She gazed at the screens like a little girl admiring a Christmas tree.
The uranium nuclei were gliding right on through. No glitches. Wonderful. The nuclei started off in an ordinary electric field accelerator, then passed through the Booster ring, then to the big, circular Alternating Gradient Synchrotron. It was the destiny of Nobel-winning machines to become the mere handmaidens of later accelerators; these once-grand devices now humbly handed energetic nuclei into the RHIC.
Once upon a time, in the now-fading Golden Age of the field, such machines had dazzled the physics community, working ever-deeper into the fabric of reality with ever-larger hammers, smashing ever-smaller walnuts. A long march, from the tabletop cyclotron to the aborted Superconducting Supercollider—which had proved to be not so super when it got canceled, sucking over three billion dollars into a useless racetrack hole in Texas. A pricey condo for fire ants and prairie dogs.
Still, the faith of the field was that every new, bigger accelerator would yield up a gratifying plethora of new particles, fresh physics. Now the Standard Model predicted that the particle zoo was nearly complete. From fat protons down to tiny leptons, then on to more exotic quarks by the mid-1990s, the particle species obligingly turned up on cue, at higher energy levels. RHIC was hunting bigger game, though—a new regime of matter itself.
“Logging is going right,” she told Zak crisply.
“Right, right, great, hey?” He had never been at a run initiation before and his eyes danced.
“Your Core Element? Logging right?” a technician asked her.
“Dead on,” she said proudly.
The Core Assembly was the University of California at Irvine’s contribution to the Brookhaven Lab’s BRAHMS detectors. Alicia had worked on nothing else since her arrival at UCI three years ago. Following up on her UC–Berkeley thesis, she had designed and built it with her small team of graduate students and postdocs. Running it now gave her an inexpressible sensation of lightness, like flying on joy alone.
A particle detector that ran beautifully was either obsolete or hadn’t been designed close enough to the cutting edge of the technology. But in the months of getting the Core Assembly up and running right, her team had beaten all the problems.
Now data acquisition computers tasted the data stream, regularly reporting back with pictures of interesting collisions. Every single collision event got stored onto big spinning laser disks, holographic optical platters. Colored lines showed incoming U-238 nuclei, which then shattered each other into showers of lesser lines, curving off in mad confusion. Events bloomed into gorgeous bouquets. Numerals at the screen’s borders reported energies and times, remorselessly dissecting the beauty as bluntly as a biologist sectioned a frog. All these splendors were frozen from a slice of time so thin that no living thing could register even a million of them, laid in order.
Humans lived too slowly, too crudely, she reflected. Sloppy, slow beasts they were. Yet they reached down with electric scalpels and cut into the heart of tiny moments.
Then things started going wrong.
“Event rate is down,” Zak announced an hour later, calling her from the counting room. She went over there to find trouble brewing.
Zak was proud to be left to monitor beam performance, thinking it an important job. In truth nobody expected RHIC’s beam to burp or stray; the Collider had been performing well above expectations ever since its shakedown runs. But postdocs seldom got a chance to feel significant around here.
“Huh?” one of the technicians said. “You’re probably reading it wrong.”
Alicia peered at the data stream. Her face stiffened. “Counts are off thirty percent,” she agreed.
“It dropped all of a sudden,” Zak said.
“Got to be a glitch,” the technician said.
“A big glitch,” Alicia said, her voice tight and high.
By now the room had calmed down for the long haul of the run. Heads turned as operators murmured.
WE LOSING A BEAM? Alicia typed on her console and answered herself, “Nope. They’re coming in steady.”
“This a normal failure mode?” Zak asked.
“Sure,” one of the operators said. “Could be any of a dozen causes.”
“Like what?” Zak persisted.
Alicia smiled. He was learning to extract information, prying it loose if necessary.
“Module mismatch, detector failure, plenty of possible malfs,” the operator said. “We’ll find it.”
But they didn’t.
The net number of collisions in the beam intersection region kept dropping. Uranium nuclei streamed steadily into the BRAHMS. Magnetic fields in the vicinity were constant. Yet somehow the beams were not finding each other. At these collision rates, they would not get enough good data.
They ran two more hours before Alicia ran out of patience. By then the collision flux was only a few percent of what they had been seeing four hours earlier. Technicolor flowers seldom bloomed on the big screens. She paced, slurped bad coffee, used the elaborate detector monitoring programs, paced some more.
The operations director called her. Beam managers disliked losing flux, fearful that the whole massive system was somehow damaged. “I think there’s something wrong in the BRAHMS,” he said delicately.
“Seems like,” she said, not wanting to concede more than the obvious.
“This is a new show. I’d say you need a close-up of your apparatus. We’ll stop the beam while you do.”
“Nominal running time is ten hours!”
“Only if things are going right.”
“But we haven’t really gotten started and—”
“Look, you people can get in there, maybe find a quick fix. We’ll go back on the air right away.”
“Quit so soon?” Alicia said, knowing that there wasn’t a damn thing she could do about it.
5
BRAHMS could look over a wide range of angles for evidence of a quark-gluon plasma. Nuclei meeting head-on made a hot “gas” of gluons and quarks. This tiny violence squeezed matter, compressing it to a hundred times the density of the incoming nucleons.
This debris cloud then expanded, cooling. BRAHMS watched the swelling central region and sampled the virulent spray, seeking fleeting evidence of a new state of matter. It somewhat resembled trying to discover steam by hurling water droplets together.
Alicia, Zak, and a technical team came into the BRAHMS bay pushing carts laden with diagnostic gear.
“Let’s start with the forward spectrometer arm,” Alicia said. This device sifted among particle energies with fine resolution, a vital role.
It seemed a good idea and they spent an hou
r on the nineteen-meter-long bulk. There was nothing wrong with it.
“Should we do the tracking elements next?” Zak asked one of the team. They nodded. Usually one would sit and await the verdict of the remote readouts, but Alicia worried that the problem might be a failed power supply or blown gas lines that they couldn’t sense from the counting room.
As “users” Zak and Alicia didn’t know the ins and outs of those who had spent a decade building BRAHMS. Alicia knew that a lot of users would sit in the control room and wait it out, trusting to the Collider team to find the glitch. But she had trained here as a graduate student herself, helped build the BRAHMS multiplicity array, the beam-beam counters, and all the rest of it. She wasn’t just another user, she told herself. Some of the team didn’t quite see it that way, but she glowered and barked and the work moved faster because of it—or so she thought.
The tracking elements were all right, too.
No trace of radioactivity in the bay.
“I’d say we look at the ring-imaging Cherenkov detector,” Alicia said to them all. “Could be it’s giving us a faulty feedback signal and—”
“I don’t think so,” one of them said.
“What?” she demanded curtly.
“Look, let’s go to lunch,” the team leader said. “We been at this awhile and it’s past time.”
She blinked. In her skittering, superheated attention time played no role; there was only the job, the puzzle, the infuriating mystery.
“Oh, okay. Look, thanks, you guys have been great.”
As they left, she took a deep breath. “Zak, help me look over here…”
She wasn’t about to knock off for food and Zak knew it. He did not even sigh as he walked with her over to the central assembly.
Down the axis of BRAHMS ran the beam pipe. The nuclei streamed through it in opposite directions, held to the straight and narrow by powerful magnets. The wreckage of their collisions spewed out into the detectors clustered close around it. The pipe was only a few centimeters across, strikingly modest for the energies it contained.
As distant users they brought their own special, home-built gear, the Core Element, to the experiment, augmenting the rest of BRAHMS. Those who had built the main body of BRAHMS tended to think they owned the facility. Alicia’s doctorate had been mostly devoted to designing and building a cylinder covered with flat, dead black surfaces. Concentric slabs of silicon held millions of tiny detectors, electronically linked, fabricated the same way commercial electronics firms made integrated circuits for computers. A charged particle passing through the dense slabs set off electrical impulses. The sum of many such pixels gave a picture of the glorious smashups.
Other detectors were long slabs in black plastic jackets, stacked shingle-style and trailing bundles of color-coded wires or optical fiber.
She typed commands into the keyboard and studied the screen, where scintillator arrays were sheets of numbers, all softly glowing green: OK. “Damn!”
Zak jerked his head up from checking connections. “What’s up?”
“There’s nothing wrong.”
“Gotta be.”
“The uranium is shooting through the beam pipe, but nothing’s coming out!”
Zak frowned. “How could the two beams miss each other?”
“They can’t. The magnets are all working fine, focus is sharp…”
She felt ridiculous shouting out the obvious, but it felt better to do it. And there was nobody here but Zak. Transgressions of the calm, sure façade were allowable in front of postdocs and graduate students.
Embarrassed, Zak said, “Uh, well, guess we just keep—”
“Let’s look at the ring imager.”
She had recovered her cool and now marched toward the big assembly at the far end of BRAHMS. Zak dutifully tagged along. She was virtually certain nothing in the ring imager could louse up the flux count, but the innate perversity of Nature could—
A loud bang. It rang from the concrete walls.
Startled, she tripped and sprawled. Fragments clanged against the walls and peppered the metal casings.
The explosion had come from behind her. What—?
“You okay?” Zak called.
“Sure. Fall down, go boom.”
Zak seemed to be trying to knock a bee out of his ear. “Wow, that was loud.”
“How in…” A hissing rose. “The vacuum system is breached!”
They hurried back to the beam pipe at the BRAHMS central focus. A big hole gaped in the pipe.
The rupture was near the center of their own detector, in the bore of one of their strongest magnets.
“I’ll call Operations,” Zak shouted, voice shrill, the adrenaline starting to hit. He ran toward the wall telephone, boots clomping. The hissing rattled her concentration.
“It’ll automatically shut down at the next lock…” her voice trailed off as foreboding clouded her face. Disaster lay all about. Shards and twisted metal lay everywhere.
Alicia stepped gingerly among the usual tangle of cables. Fragments crunched under her boots. The Core Element built by her group at UC–Irvine was a cylindrical array of special sensors, webbed by cables. She swallowed hard. It was a wreck.
A particle experimenter had to know a detector intimately to strip away the noise and find the kernel of data. That usually meant you had to have built it, gotten married to it in long nights of frustration and tedium, all invested for the all-too-brief moments of insight.
She had tossed in fevered dreams about this instrument. Now its smooth surfaces, its buried microchips, its painstakingly knitted circuits… all lay shattered.
She sagged against a gray steel support. She had put years into the Core Element, as the detector diagrams termed it. It was her intellectual child. She had entertained the complete physicists’ fantasy, from the runs at the Collider, then the job of convincing your colleagues that your beloved detector was a transparent lens, passive and objective, through which Science gazed upon the Real.
In particle physics the typical talk opened with fifteen minutes of loving detector description, known by theorists as the “Scotch tape” part of the seminar. Theorists were Platonists, trusting detectors to peer coolly into reality. Experimenters were Cartesians, endlessly worrying over the reliability of their senses.
For a long moment, head hanging, Alicia lost all senses. She plunged down a pit of despair and felt her trembling knees threaten to buckle. The hissing brought her back. Was it getting louder?
She edged her head between two big magnets and into the bore of the Irvine detector. The beam pipe was split. A whole raw section of it had blown away. Twisted shards of tough beryllium had dug into the faces of the detector and blasted whole chunks out.
The force had to have been huge. And all the bent steel and curled-back sections nestled around something quite impossible.
Sitting in the beam pipe’s rupture was a shiny sphere.
It was larger in diameter than the pipe. She approached it carefully. In its glossy sheen she saw her own reflection loom, face distorted and mouth open.
The chrome ball fizzed with light. Images seemed alive with a speckling glow.
Not a flower, but a thing of eerie beauty. What the hell?
6
High in the ceiling a horizontal steel beam whined along on wheels, riding heavy rails. “Back it off a little,” Alicia called to Zak.
The beam hoist inched backward until the permanent iron magnet it held was directly above the strange chrome ball. “Okay!” she said.
Zak called from the hoist control panel. “Look, don’t you think—”
“They’ll be back from lunch within minutes. Help me get this thing trapped.”
“But what if—”
“Now.” She kept her voice flat, commanding. Her jittery nerves came out as bossiness. She did not like the implicit hierarchy of professor/postdoc, but at times it was handy. Still… “Uh, please.”
The sphere had not moved, despite her proddin
g it with a wooden two-by-four. A steel bar would have stuck to the magnet poles. Then she noticed that the sphere made no contact with the beam line sheath. It floated a millimeter away, nothing visible supporting it.
That left only one possibility. The focusing magnetic fields held it firmly lodged in the middle of the detector complex. Two chilled superconducting magnets bracketed the focus point. There were smaller U-shaped magnets kept in a reserve bay, made of permanently magnetized steel.
If she could bring the U-shaped permanent magnet directly down upon the sphere, then pulse the other magnets in the configuration, she might get the sphere hung up in the permanent magnet’s fields. A handoff using invisible, rubbery forces.
“Okay, let’s fiddle with the current controls,” she said.
The nearby magnets could be overridden through the keyboard she carried. A few keystrokes turned down the strong fields surrounding the region of beam line rupture. Did she see the sphere bob, as though responding to the grip of unseen fields?
She had been cautious, never touching the sphere herself. Poked with a rod, it seemed solid. Yet the way it reflected images with a speckled pattern was unsettling. Laser beams had that odd quality, as the light matched wavelengths and made bright patches alternate with dark hollows. How could this thing do that?
It must be a conductor, because the beam line’s strong magnetic fields held it in place. A rock, say, would have fallen straight through. When she realized that, she saw an opportunity.
“Careful… bring the permanent down…”
She eyed the big U shape as the poles of the magnet neared the sphere. If she pulsed the other magnets just right, she could force the sphere into the magnetic web of the more powerful permanent iron magnet.
“Lower… little more…”
The sphere wobbled again. She typed in more commands to adjust the surrounding focusing fields. The sphere rose into the air, toward the magnet’s poles. It moved as if against a gummy resistance, sluggish.
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