Thursday, Oct. 24, 2013

Have a safe day!

Thursday, Oct. 24

11 a.m.
Intensity Frontier Seminar - WH8XO
Speaker: Kate Scholberg, Duke University
Title: Supernova Neutrinos


3:30 p.m.

Friday, Oct. 25

3:30 p.m.

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Marcelle Soares-Santos, Fermilab
Title: Early Results from DES

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

Ongoing and upcoming conferences at Fermilab


Take Five

Weather Partly sunny

Extended forecast
Weather at Fermilab

Current Security Status

Secon Level 3

Current Flag Status

Flags at full staff

Wilson Hall Cafe

Thursday, Oct. 24

- Breakfast: Canadian bacon, egg and cheese Texas toast
- Breakfast: Mexican omelet
- Steak soft tacos
- Smart cuisine: Spinach and jack cheese enchiladas
- Country fried steak
- Grilled-vegetable sandwich
- Sweet and sour chicken
- Beef barley soup
- Chef's choice soup
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Oct. 25

Wednesday, Oct. 30
- Chicken satay
- Jasmine rice
- Sauteed pea pods
- Coconut cake

Chez Leon menu
Call x3524 to make your reservation.


Fermilab Today

Director's Corner

Frontier Science Result

Physics in a Nutshell

Tip of the Week

User University Profiles

Related content


Fermilab Today
is online at:

Send comments and suggestions to:

Visit the Fermilab
home page

Unsubscribe from Fermilab Today


Climate affects number of birds seen at Fermilab

A peregrine falcon stands on a ledge on Wilson Hall's 15th floor. While changes in climate have caused a decline in on other types of birds at Fermilab, certain predatory birds like this falcon have seen an uptick. Photo: Reidar Hahn

According to the Fermilab Bird List, the lab is a haven for more than 200 bird species. But changes in climate have led to the decline of some species in recent years, bird monitors say.

Peter Kasper, Fermilab physicist, member of the bird counting club and author of the Birds of Fermilab website, began the practice of surveying birds in 1987. His system comprises annual Christmas and spring bird counts as well as surveys of species seen over eight-day periods. The data is divided into five-year periods that are charted online.

For an inland site, Fermilab is propitious for birds, Kasper said, since its grasslands and bodies of water provide a suitably diverse habitat.

Kasper describes local changes in climate as having a dramatic effect on the bird population at Fermilab, especially among waterfowl. He says birds such as ducks and geese time their migration with the availability of food and water, which are weather-dependent. When warmer temperatures linger longer, birds head south later in the year. Fermilab's data also show them coming back sooner.

Some species don't come back at all.

"We have seen plummeting numbers of birds, especially warblers, in the spring and fall," said Dave Spleha, a local community member that helps monitor the lab's bird population and run the Birds of Fermilab website.

There is a very narrow gap in which migratory birds can breed, especially shorebirds that breed in the arctic tundra.

"So they need to get to their breeding site as fast as possible when the weather breaks," Spleha said. "If they are delayed even a little bit, it ultimately affects their population."

Spleha added that another reason they are seeing lower numbers at Fermilab could be a reflection of global habitat losses: Warblers make their summer homes in the northern boreal forests and spend winters in tropical rainforests, both of which have seen declines. Even though Fermilab has actually improved its habitability over the years, the bird populations disturbed by these losses may not survive to return here.

These apparent trends do not bode well for biodiversity, Kasper explained. The presence of a wide variety of species is a vital part of a healthy, flourishing ecosystem.

"Where I used to be able to spot as many as 20 species in one day, I'll now only see 10 on a good day," Kasper said.

And of those species, it is common now to only come across one or two, Spleha added.

All is not doom and gloom, though. Several predatory birds, such as Cooper's hawks, bald eagles, peregrine falcons and ospreys, seem to be making a comeback at Fermilab. This is likely due in part to the fact that eagles are protected by federal law and that the latter two birds are on Illinois' endangered and threatened species list.

Sarah Witman

Several birdwatchers, led by Fermilab physicist and bird enthusiast Peter Kasper, scan the skies for signs of various bird species at a bird-watching event in 2010. Photo: Reidar Hahn
In the News

Leading dark energy theory incompatible with new measurement

From Scientific American, Oct. 22, 2013

Why is the universe being ripped apart? It's a question that has plagued astronomers since the discovery in the 1990s that the expansion of the universe is accelerating. The story is only further complicated by new observations of distant exploding stars that cast doubt on the leading explanation, called the cosmological constant.

Read more

In the News

The new physics

From FT Magazine, Oct. 18, 2013

Rolf Heuer, head of CERN, the world's biggest physics lab, has declared his next research target after triumphantly achieving the first objective: finding the Higgs particle. "We have now completed the Standard Model," he says. "It is high time for us to go on to the dark universe."

His words will resonate with an army of scientists currently working on experiments in space, on Earth and in labs deep underground to create what they call "new physics". Their hunt will go far beyond the Standard Model, which has been built up over the past 50 years to provide an internally consistent but incomplete description of the fabric of reality.

Read more

Frontier Science Result: CDF

Top leptons moving forward

This shows the asymmetry of the leptons from top decays as a function of the lepton rapidity. This is fit to a functional form, allowing the recovery of the inclusive lepton asymmetry.

For several years, physicists at the Tevatron — both at CDF and DZero — have been studying a mystery in the production of top quarks: Outgoing top quarks prefer to go in the direction of the incoming proton beam (forward), while anti-top quarks prefer the opposite direction (backward). This "forward-backward asymmetry" disagrees with the Standard Model calculations, which suggest it should be much smaller than is actually observed.

A new measurement from CDF aims to shed some additional light on this discrepancy by examining the asymmetry of leptons — electrons or their heavier cousins, muons — that are produced by the decaying top quarks. Since the leptons inherit momentum from their parent tops, they also should inherit the asymmetry. Observation of a lepton asymmetry would confirm the earlier top measurements in a very direct way. In addition, the lepton direction is sensitive to the spin direction of the top quark, and when compared to the top asymmetry, can test theories of the top asymmetry that call for polarized, or spin-aligned, top quarks.

In the practical detection of top quarks, many of the decay leptons escape through the ends of the detector and are never seen. The CDF analysis invents a technique to infer the details of the full complement of leptons from the fraction that are observed.

Using the full sample of 3,864 leptonic top events found in the full Run II Tevatron data set, the asymmetry AlFB(qyl) of the leptons in top pair events is measured to be 9.4+3.2/-2.9 percent. This is larger than the Standard Model prediction of 3.8±0.3 percent but consistent with what would be expected from the observed top forward-backward asymmetry in the case of an unpolarized top quark. This supports the prior observations of top asymmetry and further indicates that models that predict large top polarizations are unlikely to be the correct explanation for the anomalous top asymmetry.

As the catalog of Tevatron top asymmetry measurements moves to completion, the LHC will become the new hunting ground for further information on this puzzling effect.

Learn more

edited by Andy Beretvas

These CDF physicists contributed to this data analysis. Top row, from left: Dan Amidei, Ryan Edgar, Dave Mietlicki and Tom Schwarz, all from the University of Michigan. Bottom row, from left: Jon Wilson and Tom Wright, both from the University of Michigan, and Joey Huston from Michigan State University.
Photo of the Day

You say cicada, I say cicada

A cicada rests in front of Wilson Hall. Photo: Sarah Witman, DO
In Brief

Benefit annual enrollment deadline is tomorrow

The last day of Fermilab's annual enrollment for employee benefits is tomorrow, Oct. 25.

Changes made during annual enrollment will be effective Jan. 1, 2014. This year is a "passive" enrollment. If you do not make a change, your current medical coverage will automatically transfer from CIGNA to the corresponding Blue Cross and Blue Shield of Illinois plan.

If you want to participate in the 2014 flexible spending account, you must complete a change form to elect your FSA annual contribution amount.

For more information, see the email about enrollment benefits sent to all employees on Oct. 10 or visit the annual enrollment Web page.


Zumba Toning - starts today

Fermilab Family Halloween Party - Oct. 25

English country Halloween dance with live music at Kuhn Barn - Oct. 27

Deadline for Wilson Fellowship application - Nov. 1

Office of Science's Patricia Dehmer speaks at UChicago - Nov. 5

Heartland Fermilab walk-in blood drive - Nov. 5 and 6

Stars of Dance Chicago - Fermilab Arts Series - Nov. 9

Physics Slam 2013 - Fermilab Arts & Lecture Series - Nov. 15

Lepton flavor violation course in lecture series

Microsoft Office e-book available

Donate winter wear for Fermilab Coat Exchange

Money just got cheaper

Accelerate to a Healthy Lifestyle

Scottish country dancing returns to Kuhn Barn Tuesday evenings

International folk dancing returns to Kuhn Barn Thursday evenings

Ringling Bros. and Barnum & Bailey discounts