Thursday, Oct. 23, 2014

Have a safe day!

Thursday, Oct. 23

9:30 a.m.-4 p.m.
NuSTEC Training in Neutrino-Nucleus Scattering Physics - One West

2:30 p.m.
Theoretical Physics Seminar - Curia II
Speaker: Joshua Berger, SLAC
Title: Detecting Boosted Dark Matter with Large-Volume Neutrino Detectors

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

Friday, Oct. 24

9:30 a.m.-3:30 p.m.
NuSTEC Training in Neutrino-Nucleus Scattering Physics - One West

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

4 p.m.
Joint Experimental-Theoretical Physics Seminar and Fermilab Colloquium - One West
Speaker: Graham Farmelo, University of Cambridge and Northeastern University
Title: Dirac - The Theorist's Theorist

8 p.m.
Fermilab Lecture Series - Auditorium
Speaker: Henry Petroski, Duke University
Title: Success and Failure in Engineering: A Paradoxical Relationship
Tickets: $7

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Wilson Hall Cafe

Thursday, Oct. 23

- Breakfast: Canadian bacon, egg and cheese Texas toast
- Breakfast: Mexican omelet
- Steak soft tacos
- Pork and apple curry
- Chicken vindaloo
- Beef and cheddar wrap
- Sweet and sour chicken
- Chef's choice soup
- Beef barley soup
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Oct. 24
- Potato, bacon and gruyere souffle
- Medallions of beef with wild mushroom sauce
- Parsnip puree
- Sauteed Brussels sprouts
- Pear tart

Wednesday, Oct. 29
- Rouladen
- Spaetzle
- Dill baby carrots
- Baked apples

Chez Leon menu
Call x3524 to make your reservation.


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UV laser calibration system installed in MicroBooNE

Antonio Ereditato (left), head of the Laboratory for High Energy Physics at the University of Bern, and scientist Thomas Strauss, also of the University of Bern, work on MicroBooNE's UV laser calibration system. Photo: Reidar Hahn

Fermilab's MicroBooNE experiment, expected to launch in early 2015, could very well help determine whether a hypothesized fourth neutrino — referred to as a sterile neutrino — would join the three confirmed ones. Anticipating significant, perhaps momentous, findings, Fermilab and outside collaborators are working hard to ready MicroBooNE for take-off.

In late September, MicroBooNE collaborators installed a new ultraviolet (UV) laser calibration system in MicroBooNE's liquid-argon detector at Fermilab. Scientists at Switzerland's University of Bern Laboratory for High Energy Physics, a MicroBooNE collaborator, designed and built the system specifically for the project.

"This is exciting," said Fermilab's Sam Zeller, MicroBooNE co-spokesperson. "This is the first time anyone has deployed such a laser system in a liquid-argon detector for a major neutrino experiment."

Fermilab's MiniBooNE experiment (MicroBooNE's predecessor) and Los Alamos National Laboratory's Liquid Scintillator Neutrino Detector experiment raised the possibility of a fourth neutrino. However, the two experiments, while producing many cited — and some differing — results, did not have sensitive liquid-argon detectors for charting neutrino activity.

"We are recreating that same short-beamline environment, but with MicroBooNE, which has a more capable detector," said University of Bern's Michele Weber, MicroBooNE physics analysis coordinator. "We now have some means to address this new neutrino question."

Because of the high-resolution imaging capability of liquid-argon detectors such as MicroBooNE's, it is important to ensure and monitor their correct functioning. One of the calibration system's goals is to check the detector's electric field and how it transfers deposits of charge, caused by neutrino interactions with the liquid argon, to the detector's readout wires.

With the University of Bern's UV laser calibration system, ultraviolet laser beams, which are reliably straight, are shot through the argon-filled chamber when the neutrino beam is not activated to test whether the detector's critical components — wiring, electrical field — are operating maximally or are skewing data readings.

Physicist Antonio Ereditato, who heads the University of Bern laboratory, explains that a normal visible-light laser does not have enough energy to ionize the liquid argon and create tracks similar to those caused by the neutrinos. But a laser using ultraviolet light, which is higher in energy than visible light, can do the job under specific conditions.

"The system creates 'artificial' tracks that mimic the ionization tracks left by particles. In short, this ultraviolet laser system checks, monitors and calibrates the liquid-argon detector," Ereditato said.

"That allows us to measure possible image distortions everywhere," Weber said. Those distortions can then be accounted for in the data.

The laser calibration system took eight years of R&D studies to develop. The Bern team also tested it on a liquid-argon detector prototype at their lab.

"I always joke with the Bern team that the calibration system they built is like a Swiss watch," Zeller said. "The laser itself, like exquisite clockwork, sweeps across the detector. It is absolutely beautiful."

Ereditato and Weber are also very happy with the system. They feel the MicroBooNE experiment embodies the international cooperation and goodwill that bodes well for the future of particle physics.

"This experiment, which we worked so hard on, and Fermilab's opening their doors and recognizing our work is very satisfying," Weber said.

"If there is another neutrino, it could open up an entirely new particle family — so there is some exciting physics possibly around the corner," Zeller said. "We are ready to get going."

Rich Blaustein

In the News

Transatlantic network extends 100-gigabit connectivity between US and Europe

From iSGTW, Oct. 22, 2014

Scientists across the US will soon have access to new, ultra-high-speed network links spanning the Atlantic Ocean, thanks to a project currently underway to extend the Department of Energy's Energy Sciences Network (ESnet) to London, Amsterdam, and Geneva. The new links will be heavily used by particle physicists conducting research at the Large Hadron Collider (LHC) at CERN, near Geneva Switzerland — the world's most powerful particle collider.

Read more

In the News

The key to dark matter may be hidden light

From Motherboard, Oct. 18, 2014

A team of German astrophysicists is at work repurposing a large metallic mirror, originally constructed as a cosmic ray detector prototype, for use in the hunt for dark matter. Compared to the exotic supercooled xenon reservoirs currently at work at various laboratories deep underground, a regular-looking sort of mirror might not seem terribly exciting, but it's after a very different sort of dark matter prey: hidden photons.

Most dark matter detection experiments have a certain kind of dark matter in mind: WIMPs, or weakly interacting massive particles. These are particles that would have originated in the very early universe when everything existed in a state of thermal equilibrium, e.g. everything was about the same temperature and all particles had the same limited properties. Cooling brought the universe definition and differentiation.

Read more

Physics in a Nutshell

Unparticle physics

Fractals like the one above have a property known as scale invariance. Some exotic forms of matter may also be scale-invariant.

The first property of matter that was known to be quantized was not a surprising one like spin — it was mass. That is, mass only comes in multiples of a specific value: The mass of five electrons is 5 times 511 keV. A collection of electrons cannot have 4.9 or 5.1 times this number — it must be exactly 4 or exactly 6, and this is a quantum mechanical effect.

We don't usually think of mass quantization as quantum mechanical because it isn't weird. We sometimes imagine electrons as tiny balls, all alike, each with a mass of 511 keV. While this mental image could make sense of the quantization, it isn't correct since other experiments show that an electron is an amorphous wave or cloud. Individual electrons cannot be distinguished. They all melt together, and yet the mass of a blob of electron-stuff is always a whole number.

The quantization of mass comes from a wave equation — physicists assume that electron-stuff obeys this equation, and when they solve the equation, it has only solutions with mass in integer multiples of 511 keV. Since this agrees with what we know, it is probably the right equation for electrons. However, there might be other forms of matter that obey different laws.

One alternative would be to obey a symmetry principle known as scale invariance. Scale invariance is a property of fractals, like the one shown above, in which the same drawing is repeated within itself at smaller and smaller scales. For matter, scale invariance is the property that the energy, momentum and mass of a blob of matter can be scaled up equally. Normal particles like electrons are not scale-invariant because the energy can be scaled by an arbitrary factor, but the mass is rigidly quantized.

It is theoretically possible that another type of matter, dubbed "unparticles," could satisfy scale invariance. In a particle detector, unparticles would look like particles with random masses. One unparticle decay might have many times the apparent mass of the next — the distribution would be broad.

Another feature of unparticles is that they don't interact strongly with the familiar Standard Model particles, but they interact more strongly at higher energies. Therefore, they would not have been produced in low-energy experiments, but could be discovered in high-energy experiments.

Physicists searched for unparticles using the 7- and 8-TeV collisions produced by the LHC in 2011-2012, and they found nothing. This tightens limits, reducing the possible parameters that the theory can have, but it does not completely rule it out. Next spring, the LHC is scheduled to start up with an energy of 13 TeV, which would provide a chance to test the theory more thoroughly. Perhaps the next particle to be discovered is not a particle at all.

Jim Pivarski

Photo of the Day

Interpretive view

Turquoise sky and fiery leaves on the Interpretive Trail complement each other. Photo: Julianna Holden Mohler
In Brief

Revamped Linux User Group meets Oct. 29

Oct. 29 marks the first in a series of revamped meetings of the Linux User Group. The meetings will showcase Scientific Linux at Fermilab as well as related technological issues and events of interest to Linux users. In addition, tools and techniques used by various groups across the laboratory will be highlighted.

Topics for the October meeting include firewalld, a new feature in the just-released Scientific Linux 7 operating system; system administrator tools and techniques used by the Scientific Computing Division's Grid Services Department; service changes, including the recent Kerberos upgrade and Scientific Linux and Scientific Linux Fermi status; and an update on the recent HEPiX meeting.

Previously held monthly, the meetings will now be held quarterly from 1-2:30 p.m. in Wilson Hall Curia II. All Linux users are encouraged to attend.


"Nature of the Laws of Nature" - today

Lecture Series: Success and Failure in Engineering - Oct. 24

Main site ICW flush through Oct. 24

Ask Me About FermiWorks booth in atrium - Oct. 27-30

Laboratory Directed R&D information sessions - Oct. 28

Halloween party for Fermilab families in Kuhn Barn - Oct. 29

Muscle Toning by Bod Squad - register by Oct. 28

Excel 2010: Intermediate - Oct. 29

Managing Conflict - Nov. 5 (morning only)

Access 2010: Advanced - Nov. 12

Wilson Fellowship accepting applications through Nov. 14

University of Chicago Tuition Remission Program deadline - Nov. 24

Excel 2010: Advanced - Dec. 3

NALWO Playgroup meets Wednesdays at Users Center

New ebook on beam dynamics available

OSX 10.10 Yosemite not yet certified

Pace Batavia Call-n-Ride service to Fermilab

International folk dancing Thursday evenings at Kuhn Barn

Scottish country dancing Tuesday evenings at Kuhn Barn

English country dancing at Kuhn Barn

Indoor soccer

Hollywood Palms Employee Appreciation Day