Friday, Oct. 2, 2015
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Power outage at Fermilab Village tomorrow - Oct. 3

Computing Technology Day - Tuesday, Oct. 6

Muscle Toning registration due Oct. 8

FY 2017 diversity visa lottery registration open

English country dancing Oct. 4 and 25 at Kuhn Barn and special workshop Oct. 15

NALWO evening social - Oct. 7

Process Piping Design; Process Piping, Material, Fabrication, Examination, Testing - Oct. 13, 14, 15, 16

Python Programming Basics - Oct. 14, 15, 16

Interpersonal Communication Skills - Oct. 20

Access 2013: Level 2 / Intermediate - Oct. 21

Excel 2013: Level 2 / Intermediate - Oct. 22

Managing Conflict (morning only) - Nov. 4

PowerPoint 2013: Introduction / Intermediate - Nov. 18

Python Programming Advanced - Dec. 9, 10, 11

Professional and Organization Development 2015-16 fall/winter course schedule

Scheduling a meeting with the Visa Office

Outdoor soccer

Scottish country dancing Tuesdays evenings at Kuhn Barn

International folk dancing Thursday evenings at Kuhn Barn

Norris Recreation Center employee discount

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In Brief

Amateur and professional photographers take part in Fermilab Photowalk

A photographer takes shots in the Proton Assembly Building. Photo: Cindy Arnold
Photowalk participants were shown the Minos underground area. Photo: Cindy Arnold
Two photographers capture on camera a nine-cell superconducting radio-frequency cavity in the Industrial Building Complex. Photo: Cindy Arnold

Forty-five photographers from eight states visited Fermilab on Sept. 26 to point their lenses at shining accelerating cavities, miles of cabling and massive detectors for the third Fermilab Photowalk.

Both amateur and professional photographers visited five research areas at Fermilab not usually accessible by the public. Four live-tweeters also attended and captured the Photowalk on social media. You can view a collection of their posts on Storify.

The Office of Communication organized the Photowalk with the help of a group of volunteers. The event was part of a larger global Particle Physics Photowalk hosted at eight laboratories around the world. Participants can submit photos taken during the event to a global photo contest.

Visit the Photowalk Web page for more information about the contest.

In Brief

Junior high schoolers learn about insects on the prairie

Maribel Diaz (right) of Jefferson Junior High School refers to an insect book provided by Fermilab docent Toni Mueller to help students identify the kind of spider they caught. Photo: Leticia Shaddix, PPD
Students equipped with nets go on a search for insects in the Fermilab prairie. Photo: Leticia Shaddix, PPD

On Friday, Sept. 25, nearly 150 students from Jefferson Junior High School in Naperville enjoyed a day at Fermilab. They took water samples, caught and released some insects, and enjoyed lunch at the picnic tables outside Lederman Science Center.

Photo of the Day

Bison by 'Tractricious'

nature, animal, bison, sculpture, Tractricious
Bison graze by "Tractricious" in front of the Industrial Building Complex. Photo: Elliott McCrory, AD
In the News

Physicists observe weird quantum fluctuations of empty space — maybe

From Science, Oct. 1, 2015

Empty space is anything but, according to quantum mechanics: Instead, it roils with quantum particles flitting in and out of existence. Now, a team of physicists claims it has measured those fluctuations directly, without disturbing or amplifying them. However, others say it's unclear exactly what the new experiment measures — which may be fitting for a phenomenon that originates in quantum mechanics' famous uncertainty principle.

Read more

Frontier Science Result: Theory

Neutrino mixings and masses

This shows two possible ways that the three known neutrino flavors — electron, muon and tau — mix to form three massive neutrinos, named neutrinos 1, 2 and 3 (labels are to the left of each of the colored bars). On the left is the so-called normal mass ordering, in which neutrino 3, which has the least νe, is the heaviest. On the right is the inverted mass ordering, in which neutrino 3 is the lightest. The mass ordering of neutrino 1 and 2 was determined in solar neutrino experiments, principally SNO. Learn more about the figure.

If neutrinos were massless, they would be always traveling at the speed light. This means that, as Einstein informed us, their clocks would not tick, and thus neutrinos could not change from one type to another. This stands in contradiction to neutrino oscillations observed in many neutrino experiments, such as the transformation of a muon neutrino into an electron neutrino recently reported by the Fermilab NOνA experiment.

Neutrinos are produced or detected as either an electron, muon or tau neutrino (νe, νμ or ντ); these are the neutrino flavors. By contrast the neutrinos that have a definite mass and travel unchanged in time are different admixtures of the neutrino flavors, and these massive neutrinos are unimaginatively called ν1, ν2 and ν3. Yes, quantum mechanics is weird, and for neutrinos it is applicable on macroscopic scales, from one to thousands of kilometers.

The flavor content and the mass of each of the massive neutrinos are the fundamental neutrino parameters. The size or amplitude of the oscillations tell us important information about the flavor content of the massive neutrinos, whereas the rate of the oscillations (the distance neutrinos travel divided by their energy) gives us important information about the mass-squared differences of the massive neutrinos.

Thus by measuring the rate and amplitude of the oscillations, we can extract information on the mixings and mass squared differences of the massive neutrinos.

Fermilab is not the only producer of person-made neutrinos in Illinois. The electric power companies also produce neutrinos in their nuclear power plants, hundreds of megawatts of neutrinos actually, or 2×1020 neutrinos per gigawatt of thermal power per second.

The neutrinos produced in these reactors are electron antineutrinos. Physicists from around the globe are involved in three large reactor neutrino experiments: Daya Bay (China), Double Chooz (France) and RENO (South Korea). Each of these experiments has both near (0.3-0.5 kilometers) and far (1-2 kilometers) detectors. The near detector(s) are used for both the normalization and the energy spectrum of the neutrinos coming from the reactors, thereby reducing the systematic uncertainties.

In 2012, each of these experiments measured the amplitude of neutrino oscillation, which tells us the νe fraction of the massive neutrino with the least amount of this flavor, this neutrino we call ν3. This fraction is denoted by sin2θ13 and is approximately 2.2 percent. More recently both Daya Bay and RENO have reported on a precision measurement how this oscillation varies as a function of baseline divided by neutrino energy, which gives us a precision measurement of the difference of the mass squared of ν3 and some combination of the mass squareds of ν1 and ν2. This mass squared difference is denoted as Δm2ee.

What combination of the mass squareds of ν1 and ν2 is used to form this mass squared difference? Since Δm231 and Δm232 differ in size by 3 percent, and the measurement uncertainties are approaching 4 percent, to extract the most information on the fundamental neutrino parameters, precision theoretical knowledge of what combination is measured in such experiments is crucial. This is where the Fermilab Theory Department is involved.

Ten years ago, two guest scientists, Hiroshi Nunokawa and Renata Zukanovich Funchal from Brazil, and I showed, by a detailed study of the neutrino survival oscillation probability, that the Δm2 measured in such reactor experiments, Δm2ee, is nothing more complicated than "the νe average of Δm231 and Δm232." A surprisingly simple result with a direct physical meaning!

Stephen Parke

In the News

Vision of future physics

From Quanta Magazine, Sept. 22, 2015

Get Nima Arkani-Hamed going on the subject of the universe — not difficult — and he'll talk for as many minutes or hours as it takes to transport you to the edge of human understanding, and then he'll talk you past the edge, beyond Einstein, beyond space-time and quantum mechanics and all those tired tropes of 20th-century physics, to a spectacular new vision of how everything works. It will seem so simple, so lucid. He'll remind you that, in 2015, it's still speculative. But he's convinced that, someday, the vision will come true.

Read more