Friday, Oct. 31, 2014

Have a safe day!

Friday, Oct. 31

3:30 p.m.
Director's Coffee Break - WH2XO

4 p.m.
Joint Experimental-Theoretical Physics Seminar and Fermilab Colloquium - One West
Speaker: Wei Li, Rice University
Title: Recent Results from Heavy-Ion Collisions at CMS

Monday, Nov. 3

9 a.m.-6 p.m.
BSM Higgs Workshop at LPC 2014 - One West
Regiser in person
Registration fee: $40

2 p.m.
Particle Astrophysics Seminar (NOTE LOCATION) - WH6NW
Speaker: Chris Carilli, National Radio Astronomy Observatory
Title: Cosmic Reionization

3:30 p.m.
Director's Coffee Break - WH2XO

4 p.m.
All Experimenters' Meeting - Curia II

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Wilson Hall Cafe

Friday, Oct. 31

- Breakfast: spooky scramble
- Breakfast: chorizo and egg burrito
- Sloppy goblins
- Chana masala
- Freddy Krueger casserole
- Werewolf Waldorf chicken salad croissant
- Transylvania taco salad
- Lentil brain soup
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Oct. 31

Wednesday, Nov. 5
Menu unavailable

Chez Leon menu
Call x3524 to make your reservation.


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Happy Halloween

Enjoy the Halloween edition of Fermilab Today!

From symmetry

Reading the heavens with your phone

Two groups have released early versions of apps to turn your smart phone into a cosmic ray detector. Photo: Craighton Miller

Cosmic rays, most of which come speeding through the Milky Way from outside of our solar system, crash into the Earth's atmosphere at energies high enough to put the Large Hadron Collider to shame.

And all it takes to catch such an event is a smart phone.

Two groups are working on apps to turn smart phones into roving particle detectors. One group aims to educate, while the other is on a quest to create the largest cosmic ray detector array in the world.

Smart phone cameras contain sensors that help convert particles of light into the digital images that appear on your screen. Astronomers use high-powered versions of these sensors to study the light from faraway galaxies.

When a cosmic ray hits the Earth's atmosphere, it produces a shower of energetic particles that rain down on the planet. When one of those particles hits a sensor, it leaves a temporary mark — usually a single hit pixel, but sometimes a multi-pixel streak.

If these events were more common or obtrusive, they'd be the scourge of the digital photography world. As it is, it takes a little more work to find them, something the app developers are happy to do.

Justin Vandenbroucke, a physicist at the University of Wisconsin, Madison, and Levi Simons, director of citizen science at the LA Makerspace in Los Angeles, lead one group, which for the past four years has been working to build an app that teachers and students can use to create their own cosmic ray experiments. It's called DECO, Distributed Electronic Cosmic-ray Observatory.

"Instead of reading about particle interactions, students can see them on their own phones," Vandenbroucke says. "We're working with high school students to test the app, and we're working with high school teachers to develop the curriculum."

Vandenbroucke met Simons, then a physics-grad-student-turned-teacher, when they were paired together at SLAC National Accelerator Laboratory through STAR, a research experience program run through California Polytechnic State University. Their project began as an attempt to resurrect a defunct program in which students detected cosmic rays from the rooftops of schools in Southern California.

They say they envision students around the world comparing results. Young scientists in Madison and Boulder could compare data to examine the effect of altitude on cosmic ray detection. Vandenbroucke and Simons can also see students comparing their findings with magnetic field data to see if both are affected during a solar storm.

The other app-developing group has somewhat different plans.

Physicists Daniel Whiteson of the University of California, Irvine, and Michael Mulhearn of UC Davis met while working on competing experiments at Fermi National Accelerator Laboratory during grad school. They now work on competing experiments at the Large Hadron Collider at CERN.

Read more

Kathryn Jepsen

Photo of the Day

Happy Halloween, Fermilab

Daniel Noll, a visitor to the Fermilab Accelerator Physics Center, carved this jack-o-lantern at a recent holiday event in the Village. Photo: Daniel Noll, Goethe University Frankfurt
In Brief

Science Next Door November newsletter now online


The November edition of "Science Next Door," Fermilab's monthly community newsletter, is now available online. View it or subscribe to get the latest about the laboratory's public events, including tours, lectures, arts events and volunteer opportunities.

Special Announcement

Change your clocks, change your batteries

The Fermilab Fire Department wishes to remind you to check or change the batteries in your smoke detectors and carbon monoxide detectors when turning your clocks back an hour on Sunday, Nov. 2. Smoke detectors should also be checked monthly for proper operation. Statistics show that properly working smoke detectors save lives. Contact the Fire Department at x3428 with questions.

In the News

Muon g-2 storage ring starts a new life

From CERN Courier, Oct. 27, 2014

In March 2001, the Brookhaven g-2 storage ring was retired, after producing the world's best measurements of the muon's anomalous magnetic moment, aμ = (g-2)/2. However, the experiment produced a cliffhanger: the experimental result differed by 3 - 4σ from the theoretical prediction for aμ, hinting potentially at the presence of new physics beyond the Standard Model.

Read more

Frontier Science Result: CMS

Boosted W's

In the green region, we show what a W boson looks like before it decays. Moving left to right, the boson is created with more and more momentum. In the yellow region, we repeat the exercise, this time looking at the same W boson after it decays into quarks, which have then turned into jets. Finally in the pink region, we look at a jet originating from a quark or gluon. This looks much like a high-momentum W boson decaying into quarks. Because ordinary jets are so much more common, this highlights the difficulty inherent in finding high-momentum W bosons that decay into jets.

Today's article covers an interesting topic. It's interesting not because it explores new physics, but because of how it reveals some of the mundane aspects of research at the LHC. It also shows how the high energy of the LHC makes certain topics harder to study than they were during the good old days at lower-energy accelerators.

At the LHC, quarks or gluons are scattered out of the collision. It's the most common thing that happens at the LHC. Regular readers of this column know that it is impossible to see isolated quarks and gluons and that these particles convert into jets as they exit the collision. Jets are collimated streams of particles that have more or less the same energy as the parent quark or gluon. Interactions that produce jets are governed by the strong force.

Things get more interesting when a W boson is produced. One reason for this is that making a W boson requires the involvement of the electroweak force, which is needed for the decay of heavy quarks. Thus studies of W bosons are important for subjects such as the production of the top quark, which is the heaviest quark. W bosons are also found in some decays of the Higgs boson.

A W boson most often decays into two light quarks, and when it decays, it flings the light quarks into two different directions, which can be seen as two jets.

But there's a complication in this scenario at the LHC, where the W bosons are produced with so much momentum that it affects the spatial distribution of particles in those two jets. As the momentum of the W boson increases, the two jets get closer together and eventually merge into a single jet.

As mentioned earlier, individual jets are much more commonly made using the strong force. So when one sees a jet, it is very hard to identify it as coming from a W boson, which involves the electroweak force. Since identifying the existence of W bosons is very important for certain discoveries, CMS scientists needed to figure out how to tell quark- or gluon-initiated jets from the W-boson-initiated jets. So they devised algorithms that could identify when a jet contained two lumps of energy rather than one. If there were two lumps, the jet was more likely to come from the decay of a W boson.

In today's paper, CMS scientists explored algorithms and studied variables one can extract from the data to identify single jets that originated from the decay of W bosons. The data agreed reasonably well with calculations, and the techniques they devised will be very helpful for future analyses involving W bosons. In addition, the same basic technique can be extended to other interesting signatures, such as the decay of Z and Higgs bosons.

Don Lincoln

These physicists contributed to this analysis.
These CMS members were recently announced as the 2015 winners of the junior distinguished researcher fellowship awarded by the LHC Physics Center at Fermilab. The selection of the 2015 distinguished researchers was made by the LHC Physics Center management board.

New employees - October

The following regular employees started at Fermilab in October:

Flavio Cavanna, PPD; Pilar Coloma, PPD (began in September); Andrew Duranceau, CCD; Eric Flumerfelt, SCD; Charles Shaw, ESH&Q; Skyler Sherwin, PPD; Eric Vollbrecht, FESS.

Fermilab welcomes them to the laboratory.


Today's New Announcements

Ramsey Auditorium horseshoe road closure beginning Nov. 3

Silk and Thistle Scottish dancing celebrates 20 years at Fermilab at Kuhn Barn - Nov. 4

LDRD preliminary proposals due today

Managing Conflict - Nov. 5 (morning only)

English country dancing - Nov. 9

Computer Security Awareness Day 2014 - Nov. 11

Access 2010: Advanced - Nov. 12

Wilson Fellowship accepting applications through Nov. 14

UChicago Tuition Remission Program deadline - Nov. 24

Excel 2010: Advanced - Dec. 3

Performance goal setting courses - enroll in TRAIN

NALWO Playgroup meets Wednesdays at Users Center

OSX 10.10 Yosemite not yet certified

Pace Batavia Call-n-Ride service to Fermilab

Scottish country dance Tuesdays at Kuhn Barn

English country dancing at Kuhn Barn

Indoor soccer

Hollywood Palms Employee Appreciation Day

Find new classified ads on Fermilab Today.