Friday, Sept. 11, 2015
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Today's New Announcements

FermiWorks update - Sept. 12

Budker Seminar - Sept. 14

Access 2013: Level 2 / Intermediate - Oct. 7

Excel 2013: Level 2 / Intermediate - Oct. 8

PowerPoint 2013: Introduction / Intermediate - Dec. 3

Innovation Fund deadline moved - today

Open studio with Lindsay Olson - today

September AEM meeting date change to Sept. 14

Fermilab Lecture Series: Visualizing the Future of Biomedicine - Sept. 18

Back Pain and Spine Surgery Prevention Lunch and Learn - Sept. 24

Fermilab Arts Series: 10,000 Maniacs - Sept. 26

English country dancing in Kuhn Barn - Sept. 27

Workshop on Future Linear Colliders - register by Sept. 28

Python Programming Basics scheduled for Oct. 14, 15, 16

Interpersonal Communication Skills scheduled Oct. 20

Managing Conflict (morning only) scheduled for Nov. 4

Python Programming Advanced on Dec. 9, 10, 11

Mac OS X 10.8 (Mountain Lion) end of life - Dec. 14

Fermilab Prairie Plant Survey

Fermilab Board Game Guild

Fermilab Chess Club seeking new players

English country dancing at Kuhn Barn

Scottish country dancing moves to Kuhn Barn Tuesdays evenings after Labor Day

International folk dancing returns to Kuhn Barn Thursday evenings after Labor Day

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From symmetry

The birth of a black hole, live

Scientists hope to use neutrino experiments to watch a black hole form. Image: ATLAS collaboration

Black holes fascinate us. We easily conjure up images of them swallowing spaceships, but we know very little about these strange objects. In fact, we've never even seen a black hole form. Scientists on neutrino experiments such as the upcoming Deep Underground Neutrino Experiment hope to change that.

"You've got to be a bit lucky," says Mark Thomson, DUNE co-spokesperson. "But it would be one of the major discoveries in science. It would be absolutely incredible."

Black holes are sometimes born when a massive star, typically more than eight times the mass of our own sun, collapses. But there are a lot of questions about what exactly happens during the process: How often do these collapsing stars give rise to black holes? When in the collapse does the black hole actually develop?

What scientists do know is that deep in the dense core of the star, protons and electrons are squeezed together to form neutrons, sending ghostly particles called neutrinos streaming out. Matter falls inward. In the textbook case, matter rebounds and erupts, leaving a neutron star. But sometimes, the supernova fails, and there's no explosion; instead, a black hole is born.

DUNE's gigantic detectors, filled with liquid argon, will sit a mile below the surface in a repurposed goldmine. While much of their time will be spent looking for neutrinos sent from Fermi National Accelerator Laboratory 800 miles away, the detectors will also have the rare ability to pick up a core collapse in our Milky Way galaxy — whether or not that leads to a new black hole.

Read more

Lauren Biron

Video of the Day

Einstein's clocks

In this video on Einstein's theory of special relativity, Fermilab scientist Don Lincoln shows how particle physicists prove that moving clocks tick more slowly than stationary ones. View the seven-minute video. Video: Fermilab
Photos of the Day

Turbulence and stability

nature, sky, cloud, weather, Wilson Hall, building
Clouds covered Chicagoland on Thursday. This shows a view of Wilson Hall from MI-8 ... Photo: Keith Anderson, AD
nature, sky, cloud, weather, Wilson Hall, building, grass, prairie
... and from the tall grass of the prairie. Photo: Josh O'Connell, AD
nature, sky, cloud, weather, IARC, building
Clouds cover IARC ... Photo: Mike Tartaglia, TD
nature, sky, cloud, weather, Mobius Strip, sculpture
... and Mobius Strip. Photo: Marty Murphy, AD
Frontier Science Result: CMS

Holes and physics searches

Some physics analyses have more in common with a popular children's book than you'd think. Image: "Holes"

In the children's book "Holes," inmates at the juvenile correction facility called Camp Green are sentenced to spend their days digging holes, looking for treasure buried under a parched desert wasteland. According to legend, somewhere in the desert a treasure is buried. Each day, each inmate is ordered to dig a single deep hole. The hope is that eventually one of the holes will unveil the treasure.

Lots of scientific research has significant commonalities with the book. Scientists who are looking to discover something new about the world sift through their data, trying to find a treasure. While the excitement of possible discovery is what drives them, most of the things they investigate turn out to be dry and empty holes.

While less exhilarating than a discovery, each hole actually represents an advance in our knowledge of the world. After all, scientists now know one more place where the treasure is not. In fact, a plain with a thousand holes represents far more knowledge than the plain before a spade turned over the first shovelful of soil.

One physics idea that is very popular in LHC studies is a subject called supersymmetry. Supersymmetry is thought by some to be the most plausible extension of the Standard Model of particle physics. More than 10,000 papers have been written on the subject.

The principle of supersymmetry has not yet been demonstrated, but countless physics theories incorporate the idea. Scientists have no idea which of these myriad theories might actually represent the truth. Accordingly, they must investigate each theory and see if it is a treasure or just another dry hole.

In today's analysis, CMS physicists studied events containing a photon, a lepton and unobserved energy. Leptons are a class of subatomic particles of which the electron is the most common, and unobserved energy can actually be observed by looking for momentum imbalances in the detector. If scientists found more events with these characteristics than predicted by the Standard Model, it would have heralded a discovery.

Unfortunately for our subatomic treasure hunters, the measurement was perfectly consistent with the Standard Model and, in our literary analogy, was a dry hole. But a dry hole is not a failure. Tomorrow, when they return to their data, they know of one fewer site to dig. And maybe, just maybe, tomorrow's hole will end with the exciting thump of a metaphorical shovel hitting a buried wooden box.

Don Lincoln

These U.S. CMS scientists from Carnegie Mellon University made important contributions to this analysis.
In Brief

All-Experimenters' Meeting on Sept. 14, weekly schedule resumes in October

The next All-Experimenters' Meeting is Monday, Sept. 14, at 4 p.m. in Curia II. The normal weekly AEM schedule returns on Monday, Oct. 5.

In the News

Signs of neutrinos from the dawn of time, less than a second after the Big Bang

From ars technica, Sept. 8, 2015

The first 400,000 years after the Big Bang are inaccessible to us by using light; the material that filled the entire cosmos made it opaque. However, neutrinos interact very little with ordinary matter, so they could travel right through the opaque mess. Lots of these low-mass, fast-moving particles were formed in the first second after the Big Bang, so they could provide a sensitive probe of some of the very earliest moments in the Universe.

Unfortunately, these primordial neutrinos have never been detected directly, and they may have too little energy for us to ever detect them. But a new paper published in Physical Review Letters showed an unambiguous indirect detection using measurements of the cosmic microwave background light. This article marks the first clear measurement of the cosmic neutrino background, which is a significant confirmation of one of the major predictions of the Big Bang model.

Read more