Friday, April 19, 2013

Have a safe day!

Friday, April 19

1 to 2:30 p.m.
All Scientists Meeting - One West

2 p.m.
Special Particle Astrophysics Seminar (NOTE DATE AND LOCATION) - Curia II
Speaker: Christoph Weniger, University of Amsterdam
Title: Gamma-Ray Lines in the Fermi LAT Data?

3:30 p.m.

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Freya Blekman, Vrije Universiteit Brussel
Title: Searches for New Physics in Topologies Containing Beyond-Two-Generations Quarks at CMS

Saturday, April 20

8 p.m.
Fermilab Arts Series - Auditorium
Barynya: Music & Dance of Russia
Tickets: $25/$13

Monday, April 22

2:30 p.m.
Particle Astrophysics Seminar - One West
Speaker: Matt Walker, Harvard-Smithsonian Center for Astrophysics
Title: Galactic Dynamics and the Nature of Dark Matter

3:30 p.m.


Click here for NALCAL,
a weekly calendar with links to additional information.

Ongoing and upcoming conferences at Fermilab


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Wilson Hall Cafe

Friday, April 19

- Breakfast: strawberry-stuffed French toast
- Cream of butternut squash
- Blazin' buffalo wings
- Creamy tuna noodle casserole
- Smart cuisine: stir-fry beef and vegetables
- Honey mustard ham and Swiss panini
- Assorted pizza
- Chicken fajitas

Wilson Hall Cafe menu
Chez Leon

Friday, April 19
- Spinach salad
- Alaskan crab legs
- Parsley potatoes
- Grilled asparagus
- Lemon panna cotta with blueberry sauce

Wednesday, April 24
- Chopped-shrimp Waldorf salad
- Strawberry cheesecake

Chez Leon menu
Call x3524 to make your reservation.


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Special Announcement

Fermilab open today

Although parts of the Fermilab site experienced flooding yesterday, the laboratory is open today. Please observe caution signage on roads when traveling on or off site. Photo: Reidar Hahn

The Fermilab site reopened at 7 a.m. this morning. All site entrances and buildings are open and accessible, with the exception of Lab 8 in the Village, which experienced flooding conditions.

While rain has subsided and flooding concerns in the area have diminished, please continue to exercise caution while traveling to work, as well as on the Fermilab site. Please also continue to observe caution signage on roads, parking lots and areas adjacent to ponds, where standing water may still be present. If unusual conditions due to the rain event are encountered within buildings, please contact your building manager or FESS operations.

An all-hands e-mail will be sent later this morning that will include instructions on how to code your time for yesterday afternoon.

A special thanks to all staff who worked diligently on site yesterday and throughout the night to manage the heavy rain and flooding conditions.

From symmetry

Winning Photowalk images show modern beauty of science

Judges have announced the winners of the 2012 Global Particle Physics Photowalk. Photo: Joseph Paul Boccio

A stark black-and-white photo of an access tunnel 1,500 meters underground and a colorful close-up of a detector that wouldn't be out of place in a building by Catalan architect Antoni Gaudi have won the top prizes in the second Global Particle Physics Photowalk.

In September 2012, hundreds of amateur and professional photographers had the rare opportunity to explore and photograph accelerators and detectors at particle physics laboratories around the world.

The top 39 photographs from the Photowalk, including the six winners of the jury and "people's choice" competitions, are now viewable online.

"The worldwide opening of the physics laboratories for the Photowalk has been an excellent opportunity for showing the real places of physics research," says Antonio Zoccoli, a member of the executive board at the Italian Institute for Nuclear Physics. "The Photowalk tells us that scientific research is a global enterprise, which brings together intelligence, resources and technologies from different countries toward a common goal."

Read more

Kelen Tuttle

Photo of the Day

Bathing bison

Yesterday's rain formed pools and puddles all over the Fermilab site. The Fermilab bison appear to be very happy about their new pool. Photo: Jesus Orduna, Rice University
In Brief

NALWO brings new Fermilab postcards and prints to lab

New prints and postcards of Fermilab are available for sale at the Fermilab Lederman Science Center and the Arts Series office. Photo: Mady Newfield

NALWO, Fermilab's women's organization, has created a new set of Fermilab postcards and prints of striking images taken across the laboratory. The postcards and prints will be available for sale by NALWO board members and volunteers at the lectures and concert series, and are currently available at the Lederman Science Center and the Arts Series office in Wilson Hall.

NALWO has been selling a small selection of postcards for many years, but the most recent ones were outdated.

"It's great to have new and bigger images in more vivid colors," said Mady Newfield, who spearheaded the project.

The proceeds from the sales will help to fund NALWO activities.

In the News

Dark matter experiment CDMS sees three tentative clues

From BBC News, April 15, 2013

Researchers have revealed the first potential hints of the elusive material called dark matter at an underground laboratory in the US.

Though it is believed to make up a quarter of our Universe, dark matter—true to its name—has never been seen.

Scientists at the American Physical Society meeting showed three promising clues to it from the CDMS experiment.

However, they stressed the preliminary nature of the results and that more data are needed to confirm it.

Read more

Frontier Science Result: CMS

The messy strong force

A simple description of a particular event might be how a Higgs boson (top) decays into a bottom quark-antiquark pair (middle). However the reality is much messier, involving a complex spray of particles. Today's analysis is a study of the details of how a couple of quarks can turn into a much more complicated collection of particles.

When scientists explain how interactions occur at colliders like the LHC, they often have to rely on approximate descriptions. For instance, in discussions of the production and decay of a Higgs boson, we often mention that its most likely decay mode is into two bottom quarks. We then draw a simple picture, with a Higgs boson decaying and two quarks flying away from the decay point. This picture is accurate to a point, but beyond that it's far messier.

Like all quarks, bottom quarks carry color (the charge of the strong nuclear force) and feel a mutual interaction. Because of the way the strong force works, as the two quarks get farther apart, the force increases, leading to an increase in the energy stored in that force. This concentrated energy eventually results in something akin to a spark, and a gluon is emitted. Since the gluon also carries color, it too experiences a force between itself and the original quarks, and so the process repeats.

With all these colored objects flying around, the whole process of two quarks separating turns into a complicated mess of quarks and gluons, all traveling in more or less the same direction. Each of these particles carries a fraction of the energy of the original two bottom quarks, and eventually the energy each one carries is too low to radiate more gluons. The particles then combine to form various mesons, which is what we eventually observe. This blast of observable particles heading in essentially the same direction is called a jet.

A scientist analyzing the data has to cope with all of these realities. In order for an analyzer to understand how these complicated processes transform the simple idea (a Higgs boson decaying into two bottom quarks) into what is actually observed (two jets), it is very helpful to have computer programs that accurately simulate all of these effects. With this capability, physicists can compare the conceptually simple situation to the prediction of what the two jets will look like in real data. Knowing the interaction's starting and ending points, the analyzer can figure out how to extract the desired quantities from actual data measurements.

Before scientists can use this technique to analyze data with the potential for a discovery, they must compare the simulations programs to well-understood real data to verify the simulations' quality. CMS physicists studied the details of how jets formed in many different situations. The example of a Higgs boson turning into two quarks, which subsequently form jets, is among the simplest of the examples. The process of jet formation is caused by pairs of colored objects feeling a mutual interaction, but in a more complex process (like the production of a top quark-antiquark pair, in which six or more quarks and gluons are expected to be produced), things can get much messier.

CMS scientists studied the structure of jets for many different kinds of events. These studies provided both a powerful validation of the calculations and data that would further refine the programs.

—Don Lincoln

These US CMS scientists contributed to this analysis.
Construction of the ME4/2 muon chambers relies critically on these junior scientists. Under the guidance of muon experts, they clean panels, glue components, test high voltage, wind wires, assemble chambers, install and repair electronics, and perform final tests. When the LHC turns back on, they will be able to analyze LHC data with a detector they helped build.

Fermilab Arts Series: Barynya: Music & Dance of Russia - April 20

UChicago: Willy Wonka - movie and science demos - April 21

Barn Dance - April 21

Engineering Group to hold seminars at Fermilab - April 26

Changes to U.S. visa procedures - begin April 30

Hubbard Street 2 Dance - Fermilab Arts Series - May 11

Lecture: Big Science, Big Challenges - May 16

Fermilab-CERN Hadron Collider Physics Summer School open for applications

Reminder - FSA debit card PIN required

International folk dancing meets Thursday evenings in Kuhn Barn

Indoor soccer

Fermilab Golf League

Indian Creek Riding Club

Chicago Fire discount tickets

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