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	Thursday, Oct. 2, 2014

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Calendar

Have a safe day!

Thursday, Oct. 2

11 a.m.
Intensity Frontier Seminar - WH8XO
Speaker: Zelimir Djurcic, Argonne National Laboratory

2:30 p.m.
Theoretical Physics Seminar - Curia II
Speaker: Daniel Stolarski, CERN
Title: Emerging Jets

3:30 p.m.
DIRECTOR'S COFFEE BREAK - 2nd Flr X-Over

Friday, Oct. 3

3:30 p.m.
DIRECTOR'S COFFEE BREAK - 2nd Flr X-Over

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Ornella Palamara, Fermilab
Title: Detection of Short-Range Correlated Nucleon Pairs in Charged-Current Neutrino Interactions at ArgoNeuT

Visit the labwide calendar to view Fermilab events

Weather

Thunderstorms likely
76°/58°

Extended forecast
Weather at Fermilab

Current Flag Status

Flags at full staff

Wilson Hall Cafe

Thursday, Oct. 2

- Breakfast: Canadian bacon, egg and cheese Texas toast
- Breakfast: sausage gravy omelet
- Italian combo sandwich
- Finger-lickin' baked chicken
- Mom's meatloaf
- Rosemary chicken with sun-dried tomatoes
- Greek chicken salad
- Chef's choice soup
- Meatball and orzo soup
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Oct. 3
Dinner
Closed

Wednesday, Oct. 8
Lunch
- Chicken schnitzel
- Smashed mustard potatoes
- Apple, fennel and celery slaw
- German chocolate cake

Chez Leon menu
Call x3524 to make your reservation.

Neutrino Division starts up

Fermilab's newest division, the Neutrino Division, headed by scientist Gina Rameika, began on Wednesday, Oct. 1.

View the new Neutrino Division website to learn more about Fermilab's forefront neutrino program.

Feature

Fermilab and Eco Rangers safeguard the monarch butterfly

Fermilab docent Dee Huie, left, and Education Office's Maureen Hix show off the milkweed plants intended to attract monarch butterflies to the Fermilab site. The greener milkweed on the left was grown from seed and does not yet have a seed pod. The more yellow milkweed, which has a seed pod, was transplanted to the site. Photo: Rich Blaustein

The monarch butterfly has been in the news recently because of its dramatically dwindling population due to a variety of factors, including habitat loss and increased herbicide use. In fact, in the February 2014 Canada-Mexico-USA summit, the nations' leaders directed the formation of a working group on protecting the monarch butterfly, which journeys between the three countries and famously winters in a narrow band of central Mexican mountain forest.

Fermilab is doing its part to protect the monarch butterfly, the official Illinois state insect that graces the state during all its life stages, including adulthood, when the butterflies sport their beautiful orange wingspan of up to 5 inches. This spring, Fermilab's Eco Rangers, middle and high school student stewards who learn about nature and restore prairie habitat on the Fermilab grounds, started clearing a 16-foot-by-16-foot "monarch waystation" near the Lederman Science Center. They are currently planting the site with native milkweed, which provides critical food and habitat for the monarch from its egg through caterpillar stage. The Eco Rangers will continue seeding the waystation plot with milkweed and will add a variety of nectar plants, which are the adult monarch's food source.

"The purpose of a waystation is to give monarch butterflies a safe place to get nectar and a safe place to lay their eggs along the migration path," explained Maureen Hix of the Lederman Science Education Center. Hix developed and leads the Eco Rangers program.

The University of Kansas-based MonarchWatch center oversees a national effort for monarch waystations and certifies that they meet specific standards, such as for the mixture of milkweed and nectar plantings.

The Eco Rangers must meet both MonarchWatch and Fermilab guidelines, which require that the introduced plant species are indigenous to this area.

Head of Roads and Grounds Dave Shemanske and his team have assisted with getting good milkweed plants and seed from the grounds, Hix said, and Ryan Campbell, chief ecologist at Fermilab, has been advising her and the Eco Rangers on how to start and maintain a waystation.

"There's a lot of support from Roads and Grounds. It's important getting the expertise of Fermilab people behind you," Hix said. "And then the Eco Rangers do the work of digging, weeding and reseeding."

Lederman Center docent Dee Huie agrees with Hix that the Eco Rangers are doing a great job and that monarch waystations are important for conservation. She is especially gratified because of her passion for insects.

"Bringing back the insects that were once here is very important for the restoration of the prairie ecosystem," Huie said.

Hix is proud of what the Eco Rangers are doing for the monarch butterfly.

"It is going to take a while, but I have some very dedicated Eco Rangers," Hix said.

"And, actually," Huie added, "they have a very good leader in Maureen."

—Rich Blaustein

In the News

Martin L. Perl, winner of 1995 Nobel Prize for discovery of tau lepton, dead at 87

From SLAC News, Oct. 1, 2014

Martin L. Perl, a professor emeritus of physics at Stanford University and SLAC National Accelerator Laboratory and winner of the 1995 Nobel Prize in physics for discovery of the tau lepton, died Sept. 30 at Stanford Hospital in Palo Alto at the age of 87.

An elementary particle physicist, Perl was widely admired for his persistence and fortitude as a scientist. When he began the series of experiments that would lead to the Nobel Prize, the Standard Model that describes the fundamental particles and forces seemed to be complete, with matter divided into two classes: quarks and leptons. For many years Perl maintained there was no good reason for there to be two families of leptons, rather than three or even four; and when the SLAC linear accelerator turned on in the early 1960s, he immediately attempted to find a third family. It failed, but he did not give up. In a new series of experiments from 1974 to 1977 with a higher-energy machine, he and his colleagues finally discovered the first member of the third lepton family — the tau lepton, with 3,500 times the mass of its cousin the electron — in collisions between electrons and positrons, their antimatter opposites.

Frontier Science Result: CDF

Looking for rare events

This event display of the observed ΥZ candidate shows the muon candidates identified from the Upsilon (μ3 and μ4) and Z (μ1 and μ2) decays.

In 1977, Fermilab scientists discovered the bottom quark — one of six quarks in the Standard Model — through the production of upsilon mesons. An upsilon meson (Υ) is a bound state of a bottom quark and an antibottom quark.

In a new analysis using the full CDF data set, scientists conducted a search for the two mediators of the weak interaction — the W and Z boson — produced in association with an upsilon meson. This is a rare process in the Standard Model, one with a probability that is predicted to be below the sensitivity of the Tevatron.

For this result, we look for a particular Υ called the Υ(1S), which decays almost immediately. Its lifetime is 1.2 x 10^-20 seconds.

One way the Υ(1S) can decay is into two muons. This decay mode is also rare, occurring in only  2.5 percent of Υ(1S) decays.

When we look for the decay of the Υ(1S) in association with a W boson, we look for two muons from the Υ plus an additional muon or electron from the W, as well as so-called missing energy — particles that go undetected but that we know must be present, given the initial energy of the interaction. When we look for the decay of the Υ(1S) in association with a Z boson, we look for two muons from the Υ(1S) plus two additional muons or electrons from the Z.

The CDF team (pictured below) searched for these two decay patterns. For the full data set, which is about a million detected Υ(1S) decays, we expected an ΥW signal of less than one: only 0.03 ± 0.01 events. The background is expected to be much larger: 1.2 ± 0.5 events. The result of one observed event is in good agreement with the expected background.

Scientists observed one very nice candidate for Υ and associated Z production (pictured above). The ΥZ signal is expected to be extremely rare, only 0.008 ± 0.002 events from the entire data set. Here the background is expected to be about 0.1 events. This is the first such event of its kind seen.

The cross section limits resulting from the analysis are currently the world's best and place restrictions on some new physics scenarios.

—edited by Andy Beretvas

Learn more

From left: Mark Kruse (Duke University), Antonio Limosani (University of Sydney, visitor at Duke University) and Chen Zhou (Duke University) are the primary analysts for this result.

Photo of the Day