Friday, Oct. 12, 2012

Have a safe day!

Friday, Oct. 12

3:30 p.m.

4 p.m.
Town Meeting - CPM2012 - Auditorium
Speaker: Pierre Ramond, University of Florida


5 p.m.
Special Seminar - Curia II
Speaker: Steve Collins, Jet Propulsion Laboratory
Title: Flying Curiosity to Mars: Delivering NASA's Rover

8 p.m.
Fermilab Lecture Series - Ramsey Auditorium
Speaker: Paul Davies, Arizona State University
Title: The Eerie Silence: ET, Where Are You?

Monday, Oct. 15

10:30 a.m.
Presentations to the Physics Advisory Committee - Curia II

2:30 p.m.
Particle Astrophysics Seminar - One West
Speaker: Chris Morrison, University of California, Davis
Title: The Universe Under a Magnifying Glass

3:30 p.m.


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

Ongoing and upcoming conferences at Fermilab


Take Five

Weather Sunny

Extended forecast
Weather at Fermilab

Current Security Status

Secon Level 3

Current Flag Status

Flags at full-staff

Wilson Hall Cafe

Friday, Oct. 12

- Breakfast: French bistro breakfast
- New England clam chowder
- Becks battered fish sandwich
- Tortellini alfredo
- Smart cuisine: herb and lemon fish
- Cuban panini
- Garden vegetable pizza by the slice
- Chili cheese nacho platter

Wilson Hall Cafe Menu
Chez Leon

Friday, Oct. 12
- Coquille St. Jacques
- Pork tenderloin with porcini sauce
- Cauliflower gratin
- Green bean amandine
- Apple pie with vanilla bean ice cream

Wednesday, Oct. 17
- Cheese ravioli with tomato basil sauce
- Caesar salad
- Peach Melba

Chez Leon Menu
Call x3524 to make your reservation.


Fermilab Today

Director's Corner

Result of the Week

CMS 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

From symmetry

Time projection chambers: a milestone in particle detector technology

At the heart of many particle physics experiments sits a device with a catchy name: the time projection chamber. With an important job and a storied history, TPCs have a special place in particle physics. Photo: Roy Kaltschmidt, Berkeley Lab

Last month, scientists on the MicroBooNE experiment began the construction of a 170-ton liquid-argon time projection chamber—a device that, at the size of a school bus, will be the biggest detector of its kind in the United States. More importantly, it will play a crucial role in recording detailed tracks of charged particles, helping the collaboration determine just how many types of neutrino oscillations exist.

This type of detector may have a futuristic name, but it already has a spot in the history of particle physics.

In 1974, a physicist at Lawrence Berkeley National Laboratory, David Nygren, developed the idea for a new type of particle detector that would forever change the way scientists study particle collisions.

Particle detectors track and identify subatomic particles produced in messy particle collisions. At the time Nygren invented the time projection chamber, or TPC, scientists had been using detectors that gave a one-dimensional picture and so could reconstruct only a handful of particles from each collision. Nygren's concept, on the other hand, allowed scientists to study tens of thousands of subatomic particles from a single event with greater accuracy than before.

Moreover, TPCs introduced a new level of performance that allowed physicists to analyze particle collisions in three dimensions. Physicists consider this new feat one of the notable advances in particle physics technology during the 20th century.

A group of scientists led by Nygren at Berkeley Lab designed and built the first major TPC and installed it at SLAC National Accelerator Laboratory in 1981 to study electron-positron collisions. Today, nearly a dozen variations of the original operate at experiments around the world, including the ALICE experiment at the Large Hadron Collider at CERN, which studies heavy ion collisions, and the T2K experiment in Japan, which uses three TPCs to study neutrino oscillation properties.

"I really didn't anticipate the list of experiments [using TPCs] to become so broad. It's very satisfying," says Nygren, who gave a presentation at Fermilab on Sept. 19 on the origins and evolution of the time projection chamber.

Read more

—Jessica Orwig

From SLAC News Center

LCLS-II Project Director John Galayda to receive Wilson Prize

The success of SLAC's Linac Coherent Light Source X-ray free-electron laser project, which opened to users in 2009 with plans for expansion already well under way, hasn't gone unnoticed.

John Galayda, who served as LCLS project director and is now directing its sequel, LCLS-II, has been named the 2013 winner of the Robert R. Wilson Prize for Achievement in the Physics of Particle Accelerators, awarded by the American Physical Society.

The prize, which honors and encourages "outstanding achievement in the physics of particle accelerators," also recognizes Galayda's work on accelerator systems at Argonne National Laboratory's Advanced Photon Source, where he also participated in the creation of a free-electron laser (FEL), and his prior work at Brookhaven National Laboratory's National Synchrotron Light Source.

The citation that will accompany Galayda's prize, to be awarded during the APS April 2013 meeting in Denver, lauds his "leadership and outstanding and pioneering contributions to the development, construction and commissioning of the LCLS ... and his contributions to the construction of the Advanced Photon Source and the National Synchrotron Light Source."

Just weeks before he learned of the prize, Galayda, who joined SLAC in 2001, accepted another award, the 2012 FEL prize, at the 34th International Free-Electron Laser conference in Nara, Japan, which also honored his achievements at LCLS and at previous sites.

Read more

Glenn Roberts Jr. and Lori Anne White
In the News

Photon reaches from beyond the grave in quantum trick

From New Scientist, Oct. 4, 2012

Einstein mockingly called it "spooky action at a distance": the finding that quantum particles can influence each other regardless of how far apart they are. We can only imagine his horror at a new experiment that extends the idea to time by entangling a pair of photons that never coexisted. As well as expanding the reach of quantum theory's baffling implications, the experiment could improve long-distance cryptography.

At the heart of the phenomena is entanglement, in which the quantum states of two entities become linked. The implications of this for spatially distant particles stumped even Einstein, but things got still stranger last year. Joachim von Zanthier of the University of Erlangen-Nuremberg in Germany and his colleagues showed that, in principle, entanglement could also work for particles that have never existed at the same time.

Read more

CMS Result

Hunting for the platypus particle

Leptoquarks would be produced in pairs, and each would decay into a lepton (such as an electron) and a quark (which becomes a jet). This is one of the leptoquark-like events found in the CMS data set. There are too few like this to rule out standard physics explanations.

Last week's Physics in a Nutshell described a hypothetical particle called a leptoquark. The leptoquark would have features of the far more familiar leptons and quarks, the way a platypus has features of ducks and beavers. If leptoquarks do exist, they would reveal a deep connection between these two fundamental classes of particles.

Physicists have been searching for leptoquarks for years, but have never found one. If they do exist, then they must have a higher mass than previous experiments were able to reach. Leptoquarks could also allow ordinary matter to spontaneously decay, something that has never been observed. If leptoquarks have a high mass, then fluctuations in ordinary matter would rarely reach it and decays would be too infrequent to have been noticed. Both of these considerations point to a high energy scale, so it's worth looking for leptoquarks at the LHC, the highest-energy collider in the world.

CMS scientists searched through all of the data collected in 2011, which corresponds to about 500 trillion proton-proton collisions. They were looking for events in which a leptoquark and an anti-leptoquark were produced by the energy of the collision, each decaying into a lepton and a quark (or their antimatter equivalents). Some leptons, like the electron, leave a clean track through the CMS detector, while others, like the neutrino, are invisible and have to be inferred from an imbalance in the debris. A quark always produces a spray of particles known as a jet.

The search turned up a handful of events with these characteristics, but no more than would be expected from known physics processes. Therefore, this result set the most stringent limits yet on the mass of leptoquarks. CMS scientists are already hard at work examining the 2012 data, in which protons collide with a higher energy and therefore are capable of producing more massive leptoquarks, should they exist.

Why scour a mountain of data to search for a particle that might not exist? To paraphrase George Mallory, "because it could be there."

—Jim Pivarski

The U.S. physicists pictured above made major contributions to this search for leptoquarks.
A track-based level 1 trigger for the high-luminosity environment at the LHC is a substantial technical and scientific challenge. These researchers from Cornell University have investigated 3D integrated circuit technologies using simulation, chip testing and university-based nanofabrication that may lead to these technologies being part of the CMS tracker upgrade.
Photo of the Day

Bird of an unrufflable feather

A calm, stately hawk perches on a valve head just off Inner Ring Road. Photo: Paul Olderr, TD

Today's New Announcements

Talk: Flying Curiosity to Mars: Delivering NASA's Rover - today

G. Bellettini presents exhibit on Fermi's life - Oct. 15

The Eerie Silence: E.T., Where Are You? - today

Sit and Knit in celebration of I Love Yarn Day - today

Guest caller at English country and Barn dance - Oct. 14

Argentine tango classes - begin Oct. 17

NALWO Playgroup Halloween party - Oct. 26

In the Footsteps of Django - Oct. 27

Prescription safety eyewear notice

Applications being accepted for Wilson Fellowship

Abri Credit Union - money just got cheaper

Winter volleyball begins soon

Accelerate to a Healthy Lifestyle update

Mac users: upcoming changes to VPN client software

Professional development courses

Atrium work updates

Find new classified ads on Fermilab Today.

Security, Privacy, Legal  |