Friday, April 17, 2015
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Wilson Hall Cafeteria to be open this weekend

Philosophy Society: "Value of Fundamental Science" open discussion - April 23

Bardeen Engineering Leadership program lecture - today

Nominations for Employee Advisory Group due today

Discounted tickets for Creation's Birthday by Hasan Padamsee - through April 19

Barn Dance - April 19

Free yoga trial open house class - April 20

MS Excel 2013: Introduction offered two half days - April 28 and 30

2014 FSA deadline is April 30

MS Word 2013: Introduction offered two half days - May 5 and 7

Managing Conflict (a.m. only) on June 10

Interaction Management course (three days) scheduled for June 28, July 9, July 28

Performance review training for managers and supervisors - Aug. 4, 5, 6

CCD has launched the RemoteApp service

PowerPoint template and FermiMail signature options available

Fermilab Summer Day Camp

Fermilab Board Game Guild

Yoga registration due soon

Players needed for 2015 Fermilab co-ed softball league

Indoor soccer

Scottish country dancing Tuesday evenings at Kuhn Village Barn

International folk dancing Thursday evenings at Kuhn Barn

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From symmetry

Seeing the CMS experiment with new eyes

The wonders of particle physics serve as a springboard for a community-building arts initiative at Fermilab. Photo: Reidar Hahn

For many, the aspects of research at the Large Hadron Collider that inspire wonder are the very same that cast it as intellectually remote: ambitious aims about understanding our universe, a giant circular machine in the European underground, mammoth detectors that tower over us like cathedrals.

The power of art lies in the way it bridges the gap between wonder and understanding, says particle physicist and artist Michael Hoch, founder and driving force behind the outreach initiative Art@CMS. Through the creation and consumption of art inspired by the CMS experiment at the LHC, the public and scientific community approach each other in novel ways, allowing one party to better relate to the other and demystifying the science in the process.

"Art can transport information, but it has an additional layer — a way of allowing human beings to get in touch with each other," says Hoch, who has worked as a scientist on CMS since 2007. "It can reach people who might not be interested in a typical science presentation. They might not feel smart enough, they might be afraid to be wrong. But with art, you cannot be wrong. It's a personal reflection."

As the hub for the United States' participation in the CMS experiment, Fermilab, located outside Chicago, is currently showing the Art@CMS exhibit in the Fermilab Art Gallery. Organized by gallery curator Georgia Schwender, the exhibit coincides with the restart of the LHC, which recently fired up again after a two-year break for upgrades. The exhibit is not only a celebration of the LHC restart, it also aims to create connections between artists and CMS physicists in the United States.

Each artist in the Fermilab exhibit collaborated with a CMS scientist in researching his or her work. Emphasizing the collaborative nature of the exhibit, the artwork title cards display both the name of the artist and the collaborating scientist. Drawing on their interactions, the artists created pieces that invite the viewer to see the experiment — the science, the instruments and the people behind it — with new eyes.

Read more

Leah Hesla

Photos of the Day

Flying by to say hi

A turkey vulture looks in on Wilson Hall's 15th-floor occupants. Photo: Marge Bardeen, WDRS
This vulture greets the 15th floor with a spread of its wings. Photo: Barb Brooks, WDRS
In the News

Scientists are creating the first maps of the universe's dark matter

From The Washington Post, April 14, 2015

We have basically no idea what dark matter is, even though it might make up most of the cosmos. But scientists have figured out where it is, and they're mapping it in portions of the visible night sky. [You] can see the first piece of their map: It covers just 3 percent of what their data will eventually yield, but it covers around 2 million galaxies. The red and yellow regions are most dense with dark matter, and the dots represent clusters of galaxies.

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Frontier Science Result: DES

Reticulum II: Welcome to the neighborhood

This plot shows the positions of stars surrounding the newly discovered dwarf galaxy Reticulum II. Points outlined in black represent stars for which high-resolution optical spectra provided velocity measurements. Red points represent stars that were confirmed to be members of the new dwarf galaxy, while gray points are non-members. (Points that are not outlined do not have velocity measurements.)

The number of dark matter-dominated Milky Way satellite dwarf galaxies was increased by one this week. Scientists discovered the newest dwarf galaxy, Reticulum II, in data from the Dark Energy Survey. However, the DES data alone were not enough to confirm that Reticulum II was indeed a dark matter-dominated dwarf galaxy. Determining the dark matter content of Reticulum II required an extensive campaign combining observations from some of the largest telescopes in the world.

Researchers determine the dark matter content of dwarf galaxies by measuring the velocities of the stars in these objects. The higher the velocity of the stars, the more mass is required to keep the stars gravitationally bound. Stellar velocities are determined from the Doppler shift of elemental lines, which produce sharp features in the spectrum of visible light coming from the stars. Reticulum II was targeted with high- and medium-resolution spectroscopy by the Magellan 6.5-meter telescope, the Gemini 8.1-meter telescope and the VLT 8.2-meter telescope, all located in Chile. The result: Reticulum II has 470 times more mass than can be accounted for by its stars alone. This makes Reticulum II the first spectroscopically confirmed dwarf galaxy discovered outside of the Sloan Digital Sky Survey.

If dark matter is composed of weakly interacting massive particles, it may annihilate to produce Standard Model particles, including gamma rays. Regions of high dark matter density, such as dwarf galaxies, would then shine in gamma rays produced from dark matter annihilation. The strength of the gamma ray signal from each dwarf galaxy would be related to the distance and dark matter content of that galaxy. While nearby and highly dark matter-dominated, Reticulum II actually has a smaller dark matter content than several other previously known dwarf galaxies. This makes it unlikely to detect a gamma ray signal from dark matter annihilation in Reticulum II without seeing a similar signal in other nearby dwarf galaxies with greater dark matter content.

In addition to Reticulum II, researchers have found seven more dwarf galaxy candidates in the DES data. Since March 10, three additional dwarf galaxy candidates were announced using data from other surveys. Interestingly, two of these three additional candidates used the Dark Energy Camera for photometric confirmation. While spectroscopy is necessary to confirm that these candidates are indeed dwarf galaxies, it is already clear that DECam is a powerful instrument for understanding dark matter.

Alex Drlica-Wagner

These scientists worked on this analysis. Top row, from left: Josh Simon (Carnegie Observatories), Alex Drlica-Wagner (Fermilab), Ting Li (Texas A&M U). Bottom row, from left: Brian Nord (Fermilab), Keith Bechtol (U Chicago).
In the News

Subatomic particles over time: graphics from the archive, 1952-2015

From Scientific American, April 15, 2015

In the May issue of Scientific American, a familiar friend makes an appearance: a chart of fundamental particles. These particles — fermions (which include constituents of matter such as electrons and quarks) and bosons (usually carriers of force) — are at the very heart of the Standard Model of particle physics. Visualizing them in table form has become a bit of a tradition here at the magazine, as a way to introduce readers to the cast of characters in articles on the topic, and to provide context for theorized and newly described particles.

View the graphics