Physics education program QuarkNet develops global reach
Updated: 2012-11-30 18:00:00
When Virginia high school teacher Deborah Roudebush teaches physics, she doesn't exactly follow the book.
In one of her more memorable lessons, she gives her students a stopwatch and a ruler and sets a toy pig flying around the classroom. The students must use their tools to determine the speed of the pig in two different ways.
"There's no set value for pig speed," Roudebush says. "I'm teaching them to develop methods and test those methods. That's how scientists do it."
Particle colliders do not keep normal working hours. They must be tended to 24 hours a day, seven days a week, holidays included.
Few people know this as well as the family of Robert “Obie” Oberholtzer, a talented engineer whom crews at Fermilab would call—any day, any time—when something went wrong with the accelerator complex for the laboratory’s particle collider, the Tevatron.
Physicist Sam Hewamanage woke up, got ready and made his usual 15-minute drive to work. He parked his car, walked inside and sat at his workstation before digging into his primary task for the day: monitoring a particle detector located 100 meters underground on the border of Switzerland and France.
Hewamanage (pictured below) doesn’t live in Europe. He lives in Batavia, Ill., just outside of Chicago. But he can work on the CMS experiment at the Large Hadron Collider as if he were on the CERN campus, thanks to the Remote Operations Center at Fermilab.
On Friday night, Nov. 16, about 1000 people came out to Fermilab to see five physicists duke it out... with science.
The occasion was the laboratory's first ever physics slam. A physics slam is kind of like a poetry slam—the five contestants were given 12 minutes each to explain a complex particle physics concept to an auditorium filled with laymen. And they had to do it in the most entertaining way they could, because audience applause determined the winner.
If you hurl two oranges together at close to the speed of light, there’s going to be a lot of pulp. But, somewhere in the gooey mess will be the rare splinters left over from two seeds colliding.
The Large Hadron Collider at CERN works in a similar way. Protons, each made of quarks and gluons, collide and produce other particles. Roughly once every 5 billion proton collisions, everything aligns and a Higgs-like boson pops out.
Launch tour »
Time ceaselessly speeds onward in our everyday experience, never taking so much as half a step backward. Now, thanks to experimental results from the BaBar collaboration, researchers can be sure that the same is also true for single, isolated particles. Time is indeed asymmetric, even on exceedingly small scales.
ATLAS Control Room, Meyrin, Switzerland
11:30 p.m., Nov. 4
It is half an hour into the night shift at the control room for the Large Hadron Collider’s ATLAS detector, and there is nothing to do. The LHC is not running.
“We can’t do anything. We just have to wait,” says shift supervisor Adrian Vogel.
Scientists on an experiment at the Large Hadron Collider confirmed this week the existence of a particle-like structure first observed at the LHC’s predecessor, the Tevatron.
Members of the CMS collaboration announced on Nov. 14 that they had spotted a curious object, dubbed Y(4140), that the CDF experiment had detected in March 2009.
“We don’t know what it is,” says Vincenzo Chiochia, co-convener of the B physics group for CMS. “We observe a structure consistent with previous observations from the Tevatron.”
Neutrinos are among the most abundant particles in the universe, but they rarely interact with matter. Some of today’s outstanding scientific mysteries, such as why there is more matter than antimatter in the universe, could be solved by studying neutrinos and detecting their interactions with matter.
Billions of neutrinos from natural sources, including the Sun, zip through every square centimeter of the Earth each second. Yet scientists cannot easily determine their initial type or exactly how far they traveled before reaching a detector.
The universe is expanding, with every galaxy speeding away from all others at an ever-increasing rate. But it hasn’t always been that way. Eleven billion years ago, the speed of that expansion was beginning to slow as gravity pulled galaxies in toward one another. That was before dark energy came into play.
The Large Hadron Collider is the product of generations of work. As time presses on, many LHC collaborators involved from the beginning have moved on to other projects, and memories of the decade of construction that produced the largest collider yet, along with its associated detectors, have begun to dim.
This has implications for the LHC experiments, which are meant to run for years to come.
The importance of passing along knowledge to newer collaboration members is already apparent with a major work period planned to take place during the long shutdown next year.
CMS physicists observed an unusual trend in the data they collected in September when they collided protons with lead ions instead of other protons.
Particles produced in collisions tend to travel in opposite directions, but in one in roughly every 2 million collisions, the physicists saw particles travel in a common direction. Seemingly unrelated particles located apart from one another in the detector also had a tendency to travel in a common direction.
More than 300 scientists who study the sky in the high-powered light of gamma rays came together last week for five days of presentations, meetings and the chance to compare notes at the Fourth International Fermi Symposium. Acronyms flew thick and fast: SNR (supernova remnant), TGF (terrestrial gamma-ray flashes) and AGN (active galactic nucleus) were only a few of the TLAs (three-letter acronyms) to be heard.
Physicist Milind Diwan of Brookhaven National Laboratory has devoted much time and energy to neutrino research over the years, but perhaps never so literally as he did last week.