Thursday, July 23, 2015
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Fermilab bicycle commuters Web page has moved

Scottish country dancing meets Tuesday evenings in Ramsey Auditorium

International folk dancing Thursday evenings in Ramsey Auditorium

Fermilab community cleanup - today

Wilson Hall asphalt repairs - today

English country dancing at Kuhn Barn - July 26

Children's Swim Lessons Session IV registration closes July 27

Book discussion - Mindset: The New Psychology of Success - July 30

Deadline for the University of Chicago tuition remission program - Aug. 18

Call for proposals: URA Visiting Scholars Program - deadline is Aug. 31

Fermilab prairie plant survey

Users Center entrance repair on Sauk Blvd in the Village

Pool memberships on sale

Fermilab Board Game Guild

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Outdoor soccer

Bristol Renaissance Faire employee discount

Raging Waves Waterpark employee discount


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From symmetry

The Standard Model of particle physics

Explore the elementary particles that make up our universe.

The Standard Model is a kind of periodic table of the elements for particle physics. But instead of listing the chemical elements, it lists the fundamental particles that make up the atoms that make up the chemical elements, along with any other particles that cannot be broken down into any smaller pieces.

The complete Standard Model took a long time to build. Physicist J.J. Thomson discovered the electron in 1897, and scientists at the Large Hadron Collider found the final piece of the puzzle, the Higgs boson, in 2012.

Use this interactive model to explore the different particles that make up the building blocks of our universe.

See the interactive model

Kurt Riesselmann

In Brief

South Dakota Governor Daugaard visits Fermilab

From left: South Dakota Governor Daugaard, First Lady of South Dakota Linda Daugaard, Fermilab Director Nigel Lockyer and Deputy Director Joe Lykken view the Fermilab site from the 15th floor of Wilson Hall.

South Dakota Governor Dennis Daugaard visited Fermilab on Friday, July 17, to learn more about the laboratory, particle physics, the Long-Baseline Neutrino Facility and the Deep Underground Neutrino Experiment. While at the lab Governor Daugaard visited the FAST Facility, the Cryomodule Test Facility, the NOvA/MINOS hall and the 15th floor of Wilson Hall (pictured above).

In Brief

EAG will host ice cream social on July 28 in atrium

The 2015 Fermilab Employee Advisory Group invites you to an ice cream social next week. Photo: Cindy Arnold

As part of an all-hands celebration that begins at 2:30 in Ramsey Auditorium, the Employee Advisory Group will host an ice cream social on July 28 on the south patio and in the atrium. Please stop by to meet the members, learn more about the EAG and enjoy some ice cream.

Seven new members joined the EAG in June and will serve three-year terms. Most recently the EAG has helped in revitalizing the service award luncheon program as well as recommending the flexible work program, which went into effect March 1. A few of the current meeting discussion topics include a cafeteria survey, family leave policy, mentoring, diversity at the lab and PACE bus service.

Fellow employees can voice their comments and concerns through the EAG website. Click on Suggestions and Questions.

In the News

Famous fluid equations are incomplete

From Quanta Magazine, July 21, 2015

In 1900, the great mathematician David Hilbert presented a list of 23 unsolved problems worth investigating in the new century. The list became a road map for the field, guiding mathematicians through unexplored regions of the mathematical universe as they ticked off problems one by one. But one of the problems was not like the others. It required connecting the mathematical universe to the real one.

Read more

Physics in a Nutshell

Keeping cool

Liquid nitrogen plumbing often develops a layer of ice, even in the summer. Photo: tibchris

How do you cool off in the summer? A cold drink? A dip in the pool? Air conditioning? I guarantee that it involves making something else hotter: The second law of thermodynamics requires heat to flow from high temperatures to low temperatures unless additional energy is added to the system. Cooling off with water heats up the water, and air conditioners expel more heat outside than they extract from inside. Try standing next to an air conditioning exhaust on a hot day!

Cooling is a major part of particle physics experiments as well. Even if they're deep in a mine or otherwise protected from the weather, many subsystems of the experiment either generate heat or work only at very low temperatures, and each of these subsystems requires a cooling system.

The farms of computers used to analyze and collect data for an experiment are designed with cooling in mind. Part of that cooling is accomplished with air flow like the fan in your laptop and also with circulating channels built into the data center to ensure good flow. Some use tubes of water to take excess heat away, even though the water, if spilled, could damage the electronics.

Silicon detectors are great for high-precision charged-particle tracking, but suffer from an ironic flaw: They can be destroyed by radiation at room temperature. However, keeping the silicon near zero degrees Celsius helps it survive, even when inundated by particles from a collision experiment. The CMS tracker recently upgraded its fluorocarbon cooling system to deal with the higher collision rates expected in LHC Run II. It can now be kept at minus 25 C, a typical winter day on the coast of Antarctica.

The most extreme coolant is needed for superconducting magnets. The coils of wire in these electromagnets are made of niobium titanium, which has no electrical resistance at 10 Kelvin, 10 degrees above absolute zero. To reach this temperature, you need something even colder.

Most magnet cryogenics use an outer layer of liquid nitrogen at 77 K and an inner layer of liquid helium at 2 Kelvin. The helium is in an exotic state of matter, a superfluid that flows with no viscosity and is a million times more thermally conductive than ordinary helium at 3 K. It's an example of a large-scale quantum phenomenon, with bizarre properties such as quantum vortices and perpetual fountains, but for particle physics experiments, it's just a good coolant.

Jim Pivarski

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Photo of the Day

Under a rainbow

One upside to all the recent rain is that, if we're lucky, we get to see a rainbow arch over the Fermilab site. Photo: Kuldeep Kaur Maan, Panjab University
Speaking of storms and sights in the sky, head over to Fermilab at Work to see Erik Ramberg's video of last week's lightning storm.
In the News

Why is the scale of the universe so freakishly large?

From io9, July 20, 2015

"Space is big," said Douglas Adams. "You just won't believe how vastly, hugely, mind-bogglingly big it is." But why must this be so? And why does our Universe exhibit such tremendous scale, from the very tiny to the extremely large? Here are some possible answers.

Read more