Friday, March 14, 2014

Have a safe day!

Friday, March 14

3:30 p.m.

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Lauren Hsu, Fermilab
Title: Search for Low Mass WIMPs with SuperCDMS

Saturday, March 15

8 p.m.
Fermilab Arts Series - Auditorium
The Fantasticks: Steampunk Version - Nebraska Theatre Caravan
Tickets: $30/$15

Monday, March 17

2 p.m.
Particle Astrophysics Seminar - Curia II
Speaker: Pierre Sikivie, University of Florida
Title: An Argument that Dark Matter is Axions

3:30 p.m.

4 p.m.
All Experimenters' Meeting - Curia II
Special Topic: T979 Quark and Sapphire Cherenkov Counters

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

Ongoing and upcoming conferences at Fermilab


Take Five

WeatherMostly sunny

Extended forecast
Weather at Fermilab

Current Security Status

Secon Level 3

Current Flag Status

Flags at full staff

Wilson Hall Cafe

Friday, March 14

- Breakfast: blueberry-stuffed French toast
- Breakfast: chorizo and egg burrito
- Tuna melt
- Smart cuisine: white fish florentine
- Kielbasa and kraut
- Eggplant parmesan panino
- Cilantro lime chicken bowl
- Clam chowder
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu
Chez Leon

Friday, March 14

Wednesday, March 19
- Ham and gruyere crepes
- Cabbage salad
- Caramel macchiato cheesecake

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

In Brief

"Particle Fever" opens today in Naperville and Chicago

"Particle Fever," the documentary on the hunt for the Higgs, hits the AMC Showplace Naperville 16 and the Music Box Theatre in Chicago today.

Advance tickets are available online at the Music Box Theatre and AMC Naperville websites.

Scientists on LHC experiments will be at select screenings at the Naperville AMC to chat with audience members:

Friday, March 14, 7:40 p.m.
Taylor Childers (Argonne), Jim Hirschauer, Don Lincoln and Verena Martinez Outschoorn (all from Fermilab)

Saturday, March 15, 7:40 p.m.
Kevin Burkett, Oliver Gutsche (both from Fermilab), Tom LeCompte (Argonne) and Rafael Lopes de Sa (Fermilab)

Sunday, March 16, 2 p.m.
Ben Auerbach (Argonne), Rick Cavanaugh, Kurt Riesselmann and Elizabeth Sexton-Kennedy (all from Fermilab)

For a sneak peek, view the 2-minute trailer.

From symmetry

The Instrumentation Frontier

Devices designed for science can open both the wonders of the cosmos and new possibilities in everyday life. Image: Sandbox Studio

Half a millennium ago, Dutch spectacle-makers put lenses together in new ways and invented the telescope and the microscope. Novel instruments have been the key to scientific discovery throughout history. In particle physics, new technologies brought the field into the electronic era, enabling the discovery of the top quark and the Higgs boson and contributing to establishing the Standard Model of fundamental particles and forces.

"Technologies are transformative," says physicist Marcel Demarteau, a senior scientist at Argonne National Laboratory. "New technologies have made it possible to measure the universe at the dawn of time, probe the dark sector, study the asymmetry between matter and antimatter, and track down the secrets of the elusive neutrino."

Whether the search is for supersymmetric particles or distant quasars, detectors are the sine qua non of particle physics and cosmology. Particle physics has pushed detector technology forward for decades, and new materials and innovative industrial techniques offer the potential to do so again. New technologies can find their way into daily life as well.

Thick chips for searching the skies
Twenty years ago, scientists assumed the pull of gravity was slowing the universe's expansion. The international Supernova Cosmology Project, based at Lawrence Berkeley National Laboratory, set out to measure how the universe was changing by observing Type Ia supernovae, exploding stars whose consistent brightness makes them dependable standard candles for establishing cosmic distances.

By comparing Type Ia distances and redshifts — a direct measure of expansion, which stretches the light traveling from the supernovae to longer wavelengths — the SCP team and the rival High-Z Supernova Search Team discovered, to their astonishment, that the universe is actually expanding at an accelerating rate.

This was the first evidence that dark energy is pushing the universe apart, but finding it wasn't easy: The most advanced detectors of the day performed poorly with highly redshifted light.

Saul Perlmutter, who heads the SCP, recalls that in 1994, "we were having problems with the red sensitivity and internal reflections at red wavelengths in existing astronomical CCDs."

At the time, CCDs — the charge-coupled devices found in digital cameras — were the cutting-edge technology for replacing photographic plates in astronomy. CCDs capture photons and convert them to electrical signals. But typical astronomical CCDs have to be shaved to a tissue-thin 20 millionths of a meter to allow charge carriers to reach the circuitry on the other side of the chip.

Read more

Paul Preuss

Photo of the Day

Perfect perch

A cedar waxwing visits Site 38 on a recent warmer day. Photo: Sue Quarto, FESS
In the News

SLAC partners with industry to produce powerful klystrons for research

From SLAC News, March 5, 2014

Thanks to a collaboration between the Department of Energy's SLAC National Accelerator Laboratory and Communications & Power Industries (CPI), research labs around the world will now be able to buy commercially manufactured klystrons that are powerful enough to accelerate electrons to high energies for next-generation physics experiments.

As part of a cooperative agreement, CPI has adapted a SLAC design to build two XL5 klystrons. They tested the first one at SLAC and delivered it in February to the Compact Linear Collider (CLIC) experiment at CERN, the European particle physics laboratory. The second klystron is scheduled to arrive at SLAC for high-power testing in April, and the company says it's in talks with several more potential customers.

Read more

In the News

Did dark matter kill the dinosaurs?

From Nature, March 7, 2014

A thin disk of dark matter running through the Galaxy might be behind the large meteorite strikes that are thought to be responsible for some of Earth's mass extinctions, including that of the dinosaurs, two theoretical physicists have proposed.

The model is based on a hypothetical form of dark matter described by the authors and their collaborators last year as a means to solve a separate cosmic conundrum. The existence of such a 'dark disk' could be tested soon by astronomical observations.

Read more

Frontier Science Result: CMS

Embracing complexity

While all particle physics is complicated, certain processes are particularly so. Studying the most common kinds of supersymmetric events predicted to be found at the LHC is like putting together an especially complex puzzle.

Sometimes you just gotta do things the hard way. Today's article describes an attempt to do just that.

Supersymmetry is a principle that one can incorporate into new or existing theories. At its core, it is nothing more than the rule that matter particles (fermions) and force carrying particles (bosons) in the theory's equations are indistinguishable from each other. While no evidence for supersymmetry has been observed, it is a very popular idea since it can fill in many physics theory holes. It can provide an explanation for why the mass of the Higgs boson is so small, explain the identity of dark matter, and show how the strong, weak and electromagnetic forces are really different faces of the same thing. Supersymmetry really is a versatile idea.

Supersymmetry itself isn't a theory. However, many theories include it, and each one makes a very different prediction. The one universal prediction in such theories is that for every known particle, there exists a corresponding, as-yet-undiscovered partner that differs only in its spin. For example, for every known fermion (quark and lepton), there is a cousin supersymmetric boson (squark and slepton). Similarly, for every known boson (photon, W and Z boson, gluon and Higgs), there is a cousin supersymmetric fermion (photino, wino, zino, gluino and higgsino). If supersymmetry is right, we have to find these cousin particles.

Physicists have been looking for these supersymmetric particles for decades now, with no luck at all. As with most searches for new phenomena, scientists looked for the easier signatures first. Because supersymmetric sleptons decay into (among other things) ordinary leptons, and because ordinary leptons are easy to identify, many early searches focused on sleptons.

However, the LHC collides not leptons but protons. That means that, if supersymmetry is real, the most likely supersymmetric particles to come out of the LHC are squarks and gluinos. These particles would decay eventually into more common quarks and gluons, which would make jets — little shotgun-like blasts of particles — in the detector, and often many jets hit the detector simultaneously.

In one particularly challenging situation, a pair of gluinos would each make a top quark-antiquark pair. Since each top quark can decay into three lighter quarks, such an event would have 12 jets. Visually, you can imagine such a collision as 12 randomly oriented shotguns going off simultaneously, with the pellets hitting the detector. Events like these are horribly, horribly complicated.

Complicated though these events may be, CMS scientists went looking for them, and find them they did. The problem is that messy events like these can be created by known physics, and new physics requires that researchers find an excess of events with the above-mentioned characteristics. This analysis is similar to a previous Frontier Science Result but uses collisions in the LHC with higher energy than used in the earlier analysis.

The result of this search was that no evidence was observed for the extra events predicted by supersymmetry. Thus CMS scientists were able to set stringent limits on the mass of the predicted supersymmetric particles. Now it's back to the drawing board.

Don Lincoln

These US CMS scientists contributed to this analysis. Other contributors (not shown) are: Anwar Bhatti (Rockefeller), Rick Cavanaugh (UIC and Fermilab), Jay Dittmann (Baylor), Daniel Elvira (Fermilab), Bill Gary (UC Riverside), Gheorghe Lungu (Rockefeller), Steve Mrenna (Fermilab) and Jorge Rodriguez (FIU).
These US CMS scientists have been and are now actively working on the offline jet reconstruction (jet algorithms, jet energy corrections, jet energy resolutions, jet software in CMSSW). This effort was a crucial component of this analysis.

Today's New Announcements

Overview of applied vacuum technology course - April 24-25

"Particle Fever" opens in Naperville and Chicago today

SharePoint My Site maintenance - March 14-17

Hawk talk: Raptors of the Fermilab Region - March 15

Fantasticks: Steampunk at Fermilab Arts Series - March 15

Barn Dance - March 16

URA Thesis Award competition deadline - March 20

Walk 2 Run begins March 20

Photography contest - through March 21

Weight Management registration deadline March 27

2014 FRA Scholarship applications due April 1

MySQL relational database management course - April 22-23

Have you used all of your 2013 Healthcare Reimbursement Account funds?

West bike rack area closed

Portions of west atrium stair closed for construction

Help Abri Credit Union celebrate our members and Pi Day

International folk dancing meets Thursday evenings at Kuhn Barn

Scottish country dancing meets Tuesday evenings at Kuhn Barn

Indoor soccer

Find new classified ads on Fermilab Today.