Friday, June 12, 2015
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Wilson Hall 2E restrooms and drinking fountains out of order June 12-15

Wilson Hall air conditioning shut down June 12-15

Barn Dance - June 14

Monday yoga registration due June 15

NALWO lecture: Beauty of Barns - June 16

Thursday Yoga registration due June 18

art/LArSoft course at Fermilab, free registration - Aug. 3-7

Walking Works week four winners

Wednesday Walkers

WalkingWorks program begins - register now

Pedometers available for WalkingWorks program

Fermilab Board Game Guild

Fermilab pool open, memberships available

Scottish country dancing meets Tuesday evenings at Kuhn Barn

English country dancing at Kuhn Barn

International folk dancing

H4 Training discount for Fermilab employees

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DASTOW 2015 scheduled for Friday, June 26

Register now for Daughters and Sons to Work Day activities. Photo: Cindy Arnold

School-age children of Fermilab employees, users and contractors can see physics up close on Friday, June 26, when they visit Fermilab for Daughters and Sons to Work (DASTOW) day.

Enjoy activities such as a visit to the Fermilab Fire Department, Physics Fun on 15, Remote Operations Center West open house and lunch in the Wilson Hall atrium (with Mr. Freeze). Lederman Science Center will be open and a bus will be run between Wilson Hall and the Center from 10:30 a.m. to noon (or if the weather is nice, feel free to walk!).

New this year are two programs aimed at middle and high school students: Exploring Dark Energy and Behind the Scenes at Fermilab. For a complete schedule of the day's events, visit the DASTOW website.

Advance registration is required for:
Physics Fun on 15
Geared toward kids 10 and under, Physics Fun on 15 will feature hands-on science activities offered by Fermilab's Education Office on the 15th floor of Wilson Hall. You will need to register online for this activity; the deadline is June 22.

Advance registration is recommended for:
Exploring Dark Energy, 10:45 to 11:15 a.m., One West
The universe is expanding faster and faster, and scientists believe a mysterious force called dark energy is behind it. Fermilab astrophysicist Brian Nord will talk about that force and our attempts to understand it with the Dark Energy Camera. Registering online for this activity is recommended. This is geared toward middle and high school students, but everyone is welcome.

Behind the Scenes at Fermilab, 11:30 a.m. to noon, One West
Middle- and high-school-age kids will have the opportunity to meet and hear from Fermilab employees about their interesting jobs at the lab. There will be plenty of time for questions! Registering online for this activity is recommended. This is geared toward middle and high school students, but everyone is welcome.

Exposing children to the workplace is an excellent way to show them the value of education, help them understand what their parents or relatives do at work, and get them thinking about future career options.

DASTOW is scheduled on a Friday from 8:30 a.m. until 12:30 p.m., allowing time in the afternoon for children to observe their parents while at work. If you choose instead to take vacation time in the afternoon to extend your weekend, please obtain your supervisor's approval in advance.

From symmetry

Q&A: New director-general of KEK, Masanori Yamauchi

Masanori Yamauchi

At a recent symposium about the proposed International Linear Collider, Symmetry chatted with Masanori Yamauchi, the new director-general of KEK, Japan's high-energy accelerator research organization. Yamauchi, who received his PhD in physics at the University of Tokyo, has been at the laboratory for more than 30 years.

S: When did you first become interested in physics?
MY: A long time ago, as a high school student. I read a book on symmetry and asymmetry which impressed me a lot. At university, I chose to enter the physics department.

S: What was particle physics like when you were a student?
MY: When I was a grad student, I was staying at Lawrence Berkeley laboratory and doing experiments at SLAC laboratory. At the time, things were centralized in the US and Europe. Experiments in Japan were small. The nature of collaboration at the time was different.

Read more

Kathryn Jepsen

Frontier Science Result:
Fermi Gamma-Ray Space Telescope

The hunt for dark matter turns to subhalos

A team of astrophysicists is looking for dark matter in the form of subhalos. These clumps of dark matter within the Milky Way are predicted to produce a distinctive gamma-ray signal. Image courtesy of The Aquarius Project

In addition to teaching us about pulsars, cosmic rays and supermassive black holes, the Fermi Gamma Ray Space Telescope is one of the world's premier dark matter experiments. In many models, the interactions of dark matter particles can create energetic photons, known as gamma rays. Fermi provides us with our most sensitive view of the gamma-ray sky and is able to test many of our most promising theories of dark matter.

Over the past several years, my collaborators and I have published a series of papers describing an excess of gamma rays from the region surrounding the center of the Milky Way. After many long discussions, arguments and debates, the majority of the gamma-ray astrophysics community seems to have reached a consensus that this excess is real and is in need of an explanation. One exciting possibility is that these gamma rays could be produced by dark matter particles. But even though this signal looks very much like what we expected from dark matter, we can't entirely rule out other explanations, such as a series of recent outbursts of cosmic rays or some unknown population of faint gamma-ray sources.

One way to potentially confirm a dark matter origin for this excess would be to observe the same spectrum of gamma rays from otherwise invisible clumps of dark matter — known as subhalos — elsewhere in the sky. In fact, if the gamma rays from the Galactic Center do come from dark matter particles, we estimate that Fermi should be able to detect a handful of these subhalos as bright gamma-ray sources. The challenge is that Fermi has detected hundreds of bright, unidentified sources, the vast majority of which are not related to dark matter. This large haystack of sources makes it hard to find the dark matter subhalos that are the needles we are looking for.

But in one important respect, dark matter subhalos should look different from other kinds of gamma-ray sources: They should be slightly extended or "puffy." My collaborators (Bridget Bertoni of the University of Washington and Tim Linden of the University of Chicago) and I have recently found evidence that some of Fermi's unidentified sources are in fact extended, making them seem more likely to be dark matter subhalos. We continue to scrutinize the data, and although we're not prepared to claim discovery yet, we are very excited that this new information might make it possible to independently test — and maybe even confirm — a dark matter origin for Fermi's Galactic Center gamma-ray excess.

Dan Hooper

Photo of the Day

Fly forth and multiply

A common baskettail dragonfly by Bulrush Pond lays eggs. Photo: Bridget Scerini, TD
In the News

Could the evolution of theoretical physics harm public trust in science?

From Physics Today, June 9, 2015

Consider a pair of pairs of dueling commentaries in the media. In each pair, an essay in a major national newspaper disputes another essay from a major international science weekly. Taken together, the four opinion articles cast light on the seriousness of mid-2015 public skepticism about science's special authority.

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