Friday, July 18, 2014

Have a safe day!

Friday, July 18

3:30 p.m.

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Sabine Lammers, Indiana University
Title: Vector Boson Fusion Production at ATLAS

Monday, July 21


3:30 p.m.

4 p.m.
All Experimenters' Meeting - Curia II
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Wilson Hall Cafe

Friday, July 18

- Breakfast: big country breakfast
- Breakfast: chorizo and egg burrito
- Backyard pulled-pork burger
- Asian braised beef and vegetables
- Coq au vin
- Turkey and cucumber salad wraps
- Big beef or chicken burrito
- Shrimp gazpacho
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu
Chez Leon

Friday, July 18

Wednesday, July 23
- Greek meatballs with feta yogurt dressing
- Lemon couscous
- Baklava

Chez Leon menu
Call x3524 to make your reservation.


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From symmetry

Science inspires at Sanford Lab's Neutrino Day

Science was the star at an annual celebration in Lead, South Dakota. Photo courtesy of Sanford Underground Research Facility

At the Sanford Underground Research Facility's seventh annual Neutrino Day last Saturday, more than 800 visitors of all ages and backgrounds got a glimpse of the high-energy physics experiments under way a mile below the streets of Lead, South Dakota.

After decades as a mining town, Lead has transformed in recent years into a science town. From within America's largest and deepest underground mine, where hundreds of miners once pulled gold from the earth, more than a hundred scientists now glean insights into the mysteries of the universe.

"We don't have a lot of vendors or food at Neutrino Day. It's all science," says Constance Walter, Sanford Lab's communications director. "Our hope is that even people who didn't before have a real interest in science will get excited. We want them to understand what we're doing at Sanford Lab and the impact it can have on the region."

This year, the festivities included tours of the above-ground facilities, live video chats with scientists and rescue personnel a mile underground (pictured above), a planetarium presentation, and hands-on science demos including the opportunity for kids to build battery-operated robots, use air pressure to change the size of marshmallows and learn about circuits using a conductive dough.

Science lectures also drew large crowds. Tennessee Technological University Professor Mary Kidd introduced attendees to the Majorana Demonstrator, which seeks to determine whether the neutrino is its own antiparticle and offer insight into the mass of neutrinos. Brookhaven National Laboratory physicist Milind Diwan wowed the crowd with his descriptions of the strange behavior of neutrinos and their many mysteries. And, in the keynote presentation, cosmologist Joel Primack and cultural philosopher Nancy Ellen Abrams discussed some of the most mindboggling unknowns in the universe — including the nature of dark matter and dark energy.

Read more

Kelen Tuttle

Photo of the Day

Silhouette of a swing

John Voirin, member of PPD and the Wednesday Night Fermilab Golf League at Fox Valley Golf Club in North Aurora, gets ready to swing at the 14th tee. Photo: Elliott McCrory, AD
In the News

Stalking the shadow universe

From The New York Times, July 16, 2014

For centuries people have found meaning — or thought they did — in what they could see in the sky, the shapes of the constellations echoing old myths, the sudden feathery intrusion of comets, the regular dances of the planets, the chains of galaxies, spanning unfathomable distances of time and space.

Since the 1980s, however, astronomers have been forced to confront the possibility that most of the universe is invisible, and that all the glittering chains of galaxies are no more substantial, no more reliable guides to physical reality, than greasepaint on the face of a clown.

Read more

In the News

Two big dark matter experiments gain U.S. support

From Science, July 16, 2014

For a change, U.S. particle physicists are savoring some good news about government funding. The Department of Energy (DOE) and the National Science Foundation (NSF) announced on Friday that they will try to fund two major experiments to detect particles of the mysterious dark matter whose gravity binds the galaxies instead of just one. The decision allays fears that the funding agencies could afford only one experiment to continue the search for so-called weakly interacting massive particles, or WIMPs. It also averts having to choose between the two leading WIMP-search teams in the United States.

Read more

Physics in a Nutshell

Electronvolts and all that

An electronvolt, or eV, is the amount of energy an electron or proton gains when accelerated by a one-volt battery. It is a convenient unit for particle physicists to use when they use electric fields to make beams of high energy: If they know the strength of the battery, they know the energy of the beam.

TeV. GeV. eV. You don't have to have read many Fermilab Today articles to have encountered these terms. So what the heck are they?

First, the good news: The basic idea is really easy. The term "eV" is just shorthand for electronvolt. (Note that both letters are pronounced: "ee-vee.") So what is an electronvolt? It is a measurement of energy, specifically, the amount of energy a particle with the charge of an electron gets when it is accelerated by the equivalent of a one-volt battery. That's where the term comes from: one electron accelerated by one volt gets one electronvolt of energy.

To be more precise, one eV is the amount of energy a particle with the same magnitude of electric charge as the electron gets when accelerated by the equivalent of a one-volt battery. So a proton, which has the same charge as an electron (with the opposite sign), also will gain an electronvolt of energy when it encounters a one-volt battery. But the name comes from the electron, and the unit is very convenient when scientists want to quickly know the beam energy generated from an accelerator that employs batteries of a certain voltage.

So what about those other terms, keV and all that? This is just a metric system thing. For the case of keV, it is short for "kiloelectronvolt," where "kilo" means thousand. The table shows the rest:

Symbol Metric prefix Value
k kilo thousand
M mega million
G giga billion
T tera trillion

The Fermilab Tevatron, with its TeV energy, was an accelerator that produced beams with a trillion electronvolts and contained protons with the energy they would have received if they had been accelerated by one trillion one-volt batteries (or, equivalently, a single trillion-volt battery).

So just how much energy is an eV? Well, it's actually really, really tiny. For those of you who took introductory physics, 1 eV is equal to 1.6 × 10-19 joules. If you dropped a small apple from about the height of your chest onto your foot, it would have one joule of energy. An electronvolt would be about 10 and a half billion billion times smaller than that, so we see that an electronvolt is very small. Even the TeV energy of the Tevatron is pretty small. A proton carrying a TeV of energy has about as much energy as a flying mosquito.

So how is it that we physicists can study such amazing things with a mosquito's worth of energy? In particle physics collisions, this energy is concentrated into a really, really tiny volume. When one squeezes that energy into such a small space, it is possible to heat matter to a hundred thousand times hotter than the center of the sun and to discover new particles, such as the Higgs boson, and possibly even something unexpected that will require us to rewrite the textbooks.

Don Lincoln

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Today's New Announcements

Call for applications: URA Visiting Scholars Program - apply by Aug. 25

Fermilab prairie plant survey - July 23, Aug. 9

FermiWorks for managers with direct reports

Fermilab Tango Club

Scottish country dancing Tuesday evenings in Ramsey Auditorium

International folk dancing Thursday evenings in Ramsey Auditorium

Outdoor soccer

Fermi Days at Six Flags Great America

Employee Appreciation Day at Hollywood Palms Cinema

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