Late April is always a special time of year at Fermilab. Spring is in the air, the leaves are green, the birds are singing, and adorable baby bison are born.
Baby bison season is here, and all are welcome to visit with and photograph the newborns. (They’re always a hit with young children.) Fermilab is expecting the new babies to be joined by at least 10 more over the next six weeks. The site is open every day from 8 a.m. to 8 p.m., and admission is free. You’ll need a valid photo ID to enter the site.
Fermilab’s first director, Robert Wilson, established the bison herd in 1969 as a symbol of the history of the Midwestern prairie and the laboratory’s pioneering research at the frontiers of particle physics. The herd remains a major attraction for families and wildlife enthusiasts.
And thanks to the science of genetic testing, Fermilab’s ecologist Ryan Campbell confirmed that the laboratory’s herd is 100 percent bison, with no cattle genes. Farmers during the early settlement era would breed bison with other bovine species to keep them from extinction, but Fermilab’s bison are purebred.
A herd of pure bison is a natural fit for a prairie ecosystem, like the kind that exists on the Fermilab site. Fermilab hosts 1,100 acres of reconstructed tall-grass prairie.
While you’re at the Fermilab site visiting the bison, you can learn more about our ecological efforts by hiking the Interpretive Prairie Trail, a half-mile-long trail located near the Pine Street entrance in Batavia. The Lederman Science Center also offers exhibits on the prairie and hands-on physics displays. The Lederman Center hours are Monday-Friday from 8:30 a.m. to 4:30 p.m. and Saturdays from 9 a.m. to 3 p.m. And the 15th floor of Wilson Hall is open to the public Monday-Friday from 8 a.m. to 4:30 p.m. and Saturdays and Sundays from 9 a.m. to 3 p.m.
For up-to-date information for visitors, please visit www.fnal.gov or call 630-840-3351. To learn more about Fermilab’s bison herd, please visit the wildlife area of our website.
Check out this video of the newborn baby bison.
Fermilab is America’s premier national laboratory for particle physics research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC. Visit Fermilab’s website at http://www.fnal.gov and follow us on Twitter @Fermilab.
The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit http://science.energy.gov.
The LArIAT time projection chamber will be used to conduct a proof-of-concept test for the future DUNE detector. Photo: Jen Raaf
In particle physics, the difference of a millimeter or two can make or break an experiment. In March, the LArIAT experiment began a proof-of-concept test to make sure the planned Deep Underground Neutrino Experiment (DUNE) will work well with that 2-millimeter difference.
Specifically, scientists are looking at what will happen when you increase the space between detection wires inside the future DUNE detectors.
DUNE will measure neutrinos, mysterious particles that are ubiquitous but elusive and may hold answers to questions about the origins of the universe.
Like the future DUNE detectors, LArIAT is filled with liquid argon. When a particle strikes an argon nucleus inside the detector, the interaction creates electrons that float through the argon until they’re captured by a wire, which registers a signal. Scientists measure the signal to learn about the particle interaction.
Unlike the DUNE detectors, LArIAT does not detect neutrinos. Rather, it uses the interactions of other particle types to make inferences about neutrino interactions. And very unlike DUNE, LArIAT is the size of a mini-fridge, a mere speck compared to DUNE’s detectors, which will hold about 22 Olympic-size swimming pools’ worth of liquid argon.
LArIAT scientists use a beam of charged particles provided by the Fermilab Test Beam Facility that are fired into the liquid argon. These particles interact with matter far more than neutrinos do, so the beam results in many more interactions than a similar beam of neutrinos, which would mostly pass through the argon. The higher level of interactions is what allows LArIAT to forgo the massive size of DUNE.
Results from LArIAT may help physicists better understand other liquid-argon neutrino detectors at the DOE Office of Science’s Fermilab such as MicroBooNE and SBND.
“The point of the LArIAT experiment is to measure how well we can identify the various types of particles that come out of neutrino interactions and how well we can reconstruct their energy,” said Jen Raaf, LArIAT spokesperson.
Although LArIAT doesn’t detect neutrinos, the charged-particle interactions can give scientists clues about how neutrinos interact with argon nuclei.
“Instead of sending a neutrino in and looking at what stuff comes out, you send the other stuff in and see what it does,” Raaf said.
Interactions in LArIAT are characterized primarily by a mesh of wires that detects the drift electrons. One key factor that affects the accuracy of drift-electron detection is the spacing between each wire.
“The closer together your wires are, the better spatial resolution you get,” Raaf said. But the more closely spaced the wires are, the more wires that are needed. More wires means more electronics to detect signals from the wires, which can become expensive in a giant detector such as DUNE.
To keep costs down, scientists are investigating whether DUNE will have a high enough resolution in its measurements of neutrino interactions with wires spaced 5 millimeters apart — larger than the 3-millimeter spacing in smaller Fermilab neutrino experiments such as MicroBooNE.
Simulations suggest that it should work, but it’s up to Raaf and her team to test whether or not 5-millimeter spacing will do the job.
LArIAT uses the Fermilab Test Beam Facility, which is an important part of the equation. The facility’s test beam originates from the lab’s accelerators and passes through a set of particle detection instruments before arriving at the LArIAT detector. Scientists can then compare the results from the first set of instruments with the LArIAT results.
“If you know that it was truly a pion going in to the detector, and then you run your algorithm on it and it says ‘Oh no that was an electron,’ you’re like ‘I know you’re wrong!’” Raaf said. “So you just compare how often you’re wrong with 5 millimeters versus 3 millimeters.”
She and her team are optimistic, but committed to being thorough.
“It works in theory, but we always like to measure,” she said.
This research receives support from the Department of Energy Office of Science and the National Science Foundation.
By all accounts, Fermilab founding director Robert Wilson was a charismatic individual. Here he’s seen leading the first NAL Meeting at Lab 3 in the Village. Photo: Fermilab
My first year at Fermilab was 1968. I was a maintenance man when I first started, and we did all kinds of things in the early days: digging holes for trees, planting trees, shoveling snow, plowing snow, hauling garbage. We took care of furnaces, toilets, windows, window shades. We exchanged water bottles for drinking water, moved furniture, ran errands.
I worked on Robert Wilson’s car at times, which I enjoyed. We also did a lot of yard work out at Site 29. Wilson liked it clear, and we spent at least a good summer clearing the brush in the front of the house. There were lots of hawthorn trees in the front yard. The thorns in them would fall out, and our lawn tractor would get flat tires — constantly. So we made some steel wheels for the front of the tractor.
Our crew worked closely with Wilson. He was very charismatic, very friendly and outgoing. If he met you once, he remembered you by name. We’d have hot dog cookouts in our shop on Fridays, and our boss, George (I got called little George for forever), would always invite the directorate. They came over and had hot dogs with us, and we chatted.
I appreciated Wilson’s attitude toward the lab’s trees and landscaping. I was told you needed his permission to cut a tree down or even cut a limb from a tree. According to one story, Wilson moved the beam target areas because there was a group of trees at the targets’ planned location.
Wilson didn’t like things that reminded him of the war years. He didn’t like barbed wire. One of the early jobs I did was going around cutting barbed wire off the fences. He didn’t like fences, period, but particularly didn’t like barbed wire. In one case, right across from our office was a water tower with a fence around it and some barbed wire on top. I had to go cut that off. He wanted no part of it. Eventually, he took the fence and everything down. He also didn’t like trailers or Quonset huts – anything that was military-related. Word was he was just intense about that kind of thing.
As a director, he was completely geared to building an accelerator — very hands-on in that respect.
I vaguely remember the speech he gave in front of the old director’s complex. We were all standing out in the street. He said something to the effect that we had just received a few million dollars, and we were going to spend it all in the next couple of days so we could build our machine. That was his attitude.
He was building a laboratory, and we were going to build an accelerator — today.
George Davidson is the head of transportation services at Fermilab.