Thursday, Jan. 8, 2015

Have a safe day!

Thursday, Jan. 8



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

Friday, Jan. 9

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

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Trung Le, Rutgers University
Title: Antineutrino Production of Neutral Pions in MINERvA

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Wilson Hall Cafe

Thursday, Jan. 8

- Breakfast: Canadian bacon, egg and cheese Texas toast
- Breakfast: corned beef hash and eggs
- Grilled chicken quesadilla
- Chicken vincenza with pasta
- Sweet and sour beef brisket
- Italian antipasto panino
- Italian pasta bar
- White chicken chili
- Chef's choice soup
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Jan. 9

Wednesday, Jan. 14
- Chicken marsala with linguine
- Mixed green salad
- Tiramisu

Chez Leon menu
Call x3524 to make your reservation.


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Fermilab scientists selected as 2014 APS fellows

Last month, three Fermilab scientists were named fellows of the American Physical Society, a distinction awarded each year to no more than one-half of 1 percent of current APS members by their peers.

John Campbell and Deborah Harris were named 2014 fellows to the Division of Particles and Fields. Alexander Zlobin was named a fellow to the Division of the Physics of Beams.

Several Fermilab users were also named APS fellows: David Asner (Pacific Northwest National Laboratory), Mary Bishai (Brookhaven National Laboratory), Eva Halkiadakis (Rutgers University), Wai-Yee Keung (University of Illinois at Chicago), Kevin Pitts (University of Illinois at Urbana-Champaign) and Maria Spiropulu (California Institute of Technology).

John Campbell

For work in perturbative quantum chromodynamics, especially the precise simulation of Standard Model processes in high-energy particle collisions.

Deborah Harris

For leadership in measuring the neutrino reactions that enable current and future accelerator neutrino oscillation experiments.

Alexander Zlobin

For his multiyear leadership, personal innovative contributions and achievements in the development and demonstration of new-generation superconducting accelerator magnets based on Nb3Sn superconductor.

From Dark Energy Detectives

As the sky turns: the fall and rise of the Milky Way

Although these galaxies may appear randomly strewn about the cosmos, they are actually distributed into structures that can span swaths of space and time much larger than what is seen in this image. Photo: Marty Murphy, AD, and Reidar Hahn

Lurking beneath a sea of light, an intricate pattern rustles and changes ever so slowly. It is built from dark, and nearly invisible, cosmic forces. Amidst the clumps and knots of galaxies lie empty, usually fallow spaces. While each galaxy, with its billions of stars, has a unique story of birth and evolution, we don't miss the forest for the trees. Taken as a whole, the pattern of clusters and voids in our galaxy maps can tell us about the dark forces that shape our universe.

Read more

Ross Cawthon, University of Chicago

Photo of the Day

Pillars of light

The bright side of these cold days is the occasional light show to which we're treated. These light pillars, seen from the horseshoe south of Wilson Hall and which accelerator operators first took for an aurora, appeared in the very early morning of Jan. 6. Photo: Chris Olsen, AD
In the News

The Large Hadron Collider sets its sights on dark matter

From The Guardian, Jan. 4, 2015

There is no shortage of superlatives that can be applied to the Large Hadron Collider near Geneva, though many are strange and unusual. For a start, the huge underground device, which batters beams of protons into each other at colossal energies, can fairly claim to be the coolest place on Earth. Bending protons as they hurtle round the LHC's circular 27km tunnel turns out to be a chilly business.

Read more

In the News

Indian Neutrino Observatory set for construction

From Physics World, Jan. 7, 2015

The Indian government has given the go-ahead for a huge underground observatory that researchers hope will provide crucial insights into neutrino physics. Construction will now begin on the Rs15bn ($236m) Indian Neutrino Observatory (INO) at Pottipuram, which lies 110 km from the temple city of Madurai in the southern Indian state of Tamil Nadu. Madurai will also host a new Inter Institutional Centre for High Energy Physics that will be used to train scientists and carry out R&D for the new lab.

Read more

Physics in a Nutshell

Freezing particle beams and other things

This spiderweb was overtaken by a sudden frost.

The last few days have been cold. Really cold. It prompted me to make some comparisons: cold as outer space, cold as laser beams, cold as an electron — but most of these are nonsensical. The concept of temperature only makes sense in settings with large numbers of particles and a diffuse distribution of energy, such as our everyday world. A single particle doesn't have a temperature, and the temperature of a laser beam is negative (below absolute zero).

Temperature is a relationship between the energy of a system of particles and its complexity, also known as entropy (see "Entropy is not disorder"). An ice crystal is an example of a simple, or low-entropy, state because the water molecules are aligned in rigid positions. Hot water is a more complex, high-entropy state because there are so many ways that the water molecules can tumble over one another. If it takes a lot of energy to increase the entropy a little, then the temperature is high. If it doesn't take much, then the temperature is low.

This is why an isolated particle has no temperature. It has energy but no entropy because there is only one configuration — like a single Lego brick, all alone. A bunch of particles, such as the electrons or protons in a particle beam, has energy and entropy, so you can measure the beam's temperature. If all the particles are in rigid lockstep and racing down the beam pipe with a lot of energy, it is a low-temperature beam, like a flying ice cube. In fact, cooling is an important step in preparing the beam: The random motions of the initial gas must be dampened while its collective motion is accelerated. The energy of the collective motion doesn't count toward temperature because changing the overall speed doesn't change the entropy.

Lasers are even more exotic. The source of a laser beam is made of atoms with only two (relevant) energy states: on and off. When more than half of the atoms are "on," the laser's entropy decreases, rather than increases. Half-on and half-off is a more complex state than all-on. Thus, as the energy increases, turning more atoms "on," the entropy decreases, and the temperature is negative.

Even in this bizarre case of negative temperature, absolute zero cannot be reached. Zero temperature means that a change in energy would cause an infinite change in entropy, and since entropy is ultimately a count of the number of configurations, it cannot be infinite. Laser beams approach but do not reach absolute zero from below, just as normal systems approach it from above.

So how cold is it outside, in an absolute sense? Zero degrees Fahrenheit, relative to absolute zero, is 10 percent colder than 45 degrees Fahrenheit, so if you're looking for a strong statement about the weather, we're a 10th part closer to absolute zero than we were two weeks ago.

Jim Pivarski

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Video of the Day

Hashtag: RestartLHC

The impending restart of the LHC at CERN has everyone excited. In this parody of Jimmy Fallon and Justin Timberlake's classic #Hashtag video, two U.S. LHC scientists have a Twitter conversation that gives you a sense of what's going on. View the video. Video: Fermilab

Today's New Announcements

Barn dance - Jan. 11

Lifestyle Patterns Approach to managing weight - register today

International folk dancing - today

Fermilab Arts Series presents Chicago Harp Quartet - Jan. 11

Mac OS X 10.7 (Lion) end of life Jan. 12

Goal setting in FermiWorks on Jan. 13

Free health screenings for active employees - sign up for Jan. 13-14

Lecture Series: Revealing the Nature of Dark Matter - Jan. 16

Register for ELBNF collaboration meeting - Jan. 22-23

Writing for Results: Email and More - Feb. 27

2015 FRA scholarship applications accepted until April 1

GSA updates mileage rate to 57.5 cents for 2015

OS X 10.10 Yosemite certified for use

2015 float holiday

Charitable donations through payroll deduction

The Take Five challenge and poster winter 2014/2015

Taiji and Qigong for health

Scottish country dancing Tuesdays through December and into January

Indoor soccer

Fox Valley Fitness offers employee discount