Friday, Jan. 23, 2015

Have a safe day!

Friday, Jan. 23

9 a.m.-5 p.m.
ELBNF Proto-Collaboration Meeting

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

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Eun-Joo Ahn, Fermilab
Title: Surprising Results on the Composition of the Highest-Energy Cosmic Rays

Monday, Jan. 26

2 p.m.
Particle Astrophysics Seminar - Curia II
Speaker: Mei-Yu Wang, Texas A&M University
Title: Impacts of Galaxy Formation and Alternative Dark Matter Models on Milky Way Satellite Kinematics

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

4 p.m.
All Experimenters' Meeting - Curia II

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Wilson Hall Cafe

Friday, Jan. 23

- Breakfast: big country breakfast
- Breakfast: chorizo and egg burrito
- Beer-battered fish sandwich
- Chana masala
- Caribbean jerk chicken
- Honey mustard ham and Swiss
- Chicken fajita plate
- Tomato basil bisque
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Jan. 23

Wednesday, Jan. 28
- Stuffed cabbage
- Mashed potatoes
- Apple crisp cake

Chez Leon menu
Call x3524 to make your reservation.


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Mu2e polishes off prototype module for transport solenoid

From left: Giorgio Ambrosio, Mau Lopes, Michael Lamm and Daniel Evbota show off the prototype coil module for the Mu2e transport solenoid. The prototype, here mounted on a test stand, will be one of 27 like pieces that guides muons to their target. Photo: Reidar Hahn

Mau Lopes has never waited as anxiously for a package as he did for the one that arrived late last month. From the Italian laboratory INFN-Genoa came the completed prototype of one coil module for the s-shaped Mu2e transport solenoid.

The module is an aluminum ring about a meter wide and a meter deep, wound with hundreds of turns of superconducting cable. Twenty-seven modules joined together will generate the magnetic field that forms the experiment's winding muon path.

As a project manager, Lopes had been working on the ring for a year and a half.

"It's a really important milestone for us, and so far everything has been according to plan," Lopes said.

Mu2e collaborator INFN was charged with producing the superconducting coils and integrating them into the housing shell developed at Fermilab. Scientists Pasquale Fabbricatore, Stefania Farinon and Riccardo Musenich led the manufacturing effort and have delivered what looks to be an impeccable result. After Fermilab researchers test and approve the prototype, the Mu2e project will order the full production of coil modules to form the distinctive s-shaped mid-section of the 75-foot-long experiment.

All this is in an effort to fundamentally change the face of muon research. Fermilab has thrown in its bid to be the first to find the suspected but never confirmed direct conversion of one member of the lepton family into another, specifically, of muons to electrons. Analogous processes have been observed in other elementary particles, but this long-awaited breakthrough has yet to be discovered. Fermilab researchers, though, are confident in their plans.

"There's never been an experiment quite like this," said Michael Lamm, Mu2e solenoids project manager.

The fully assembled solenoid will generate a 2-Tesla magnetic field that will guide muons from their birthplace in the production solenoid to their target in the detector solenoid. As muons travel around the first bend, they separate from each other, allowing a collimator in the middle of the "s" to screen particles for charge and momentum. As selected muons travel around the second bend, they fall back into position to hit their target.

Getting the slight bend exactly right in each segment of the transport solenoid has been a major engineering challenge.

"This type of machining has never been done as far as we know," said Daniel Evbota, a Technical Division mechanical engineer assigned to the transport solenoid. "So communicating this type of machining in 2-D drawings or even in CAD models to our vendor was a big challenge."

Preliminary tests on the prototype will first check whether the magnetic field is properly aligned. In operation, researchers will power the module's superconducting coils with 2,000 amps of current and cool them to about 4 Kelvin.

Tests at that temperature are scheduled to take place in a few months, something Lopes and his team are once again eagerly awaiting.

Troy Rummler

Video of the Day

GUTs and TOEs

Modern science is far from arriving at the ultimate and basic rules that govern the universe, but scientists have some thoughts on how this inquiry might unfold. In this video, U.S. CMS Education and Outreach Coordinator Don Lincoln tells what we know about GUTs (grand unified theories) and TOEs (theories of everything). View the video. Video: Fermilab
Photo of the Day

Ladies and gentlemen, we are sitting in center space

What a nice parking job! Someone positioned this Volkswagen perfectly centrally next to the Meson Building. Photo: Elliott McCrory, AD
In the News

Synopsis: How to spot a WIMP

From Physics, Jan. 21, 2015

Weakly interacting massive particles (WIMPs) are among the leading candidates for dark matter. Experimentalists around the world are searching for the particles in deep underground laboratories, hoping to see WIMPs as they collide with the atoms of a detector, producing nuclear recoils. But a challenge is discriminating a dark matter signal from similar background signals produced by neutrons, neutrinos, and other particles. A comparison of different detection strategies by Julien Billard at the Institute of Nuclear Physics of the University of Lyon, France, highlights those that have the best chance of spotting the elusive particles.

Read more

In the News

Particles accelerate without a push

From MIT News, Jan. 20, 2015

Some physical principles have been considered immutable since the time of Isaac Newton: Light always travels in straight lines. No physical object can change its speed unless some outside force acts on it.

Not so fast, says a new generation of physicists: While the underlying physical laws haven't changed, new ways of "tricking" those laws to permit seemingly impossible actions have begun to appear. For example, work that began in 2007 proved that under special conditions, light could be made to move along a curved trajectory — a finding that is already beginning to find some practical applications.

Read more

Frontier Science Result: Muon g-2

New detectors for the Muon g-2 experiment

Members of the Muon g-2 collaboration at Fermilab are developing this lead fluoride crystal, 14 centimeters long, and the large-area SiPMs for the experiment's detector. They will help scientists measure more precisely the energies of particles from decaying muons, as well as the decay time of the particles.

The Muon g-2 experiment at Fermilab is under construction in the new MC-1 building. It aims to measure with unprecedented precision — 140 parts per billion — a property of the muon called the anomalous magnetic dipole moment. The effort will improve upon the famous experiment at Brookhaven National Laboratory, which finished data taking in 2001.

The new Fermilab experiment aims to improve the precision with 20 times more data and by reducing key systematic uncertainties. These factors significantly affect the design of the detector, which measures the muon decay data used to deduce the magnetic dipole moment.

Now, after six years and four beam tests, members of the original team from Brookhaven along with several new collaborators have finished testing a production prototype of a new calorimeter — the detector that measures particle energies and decay time — for the Fermilab experiment. The new calorimeter design improves on its Brookhaven counterpart by reducing something called detector pile-up, which occurs when two particles strike a detector in rapid succession, and with custom electronics that can withstand higher signal rates. To address these issues, the collaboration will segment the electromagnetic calorimeter into 54 independent elements, and the signal in each of these will have an ultrashort duration in time.

The Fermilab accelerator complex will deliver a beam of polarized muons into a storage ring, which guides the muons around a circular path. Fermilab will deliver the muons at a much higher rate than the Brookhaven experiment. The detectors, positioned along the inside of the ring, are designed to operate near, but not disturb, the highly uniform and strong magnetic field of the storage ring. A combination of lead fluoride crystals, which convert deposited energy into Cherenkov photons (light), and devices called silicon photomultipliers (SiPMs), which collect photons, serves these purposes well.

After a positive muon stored in the magnetic ring decays into a positron and a pair of neutrinos, the positron curls inward and hits a calorimeter station. Its energy is converted into many thousands of Cherenkov photons in the 14-centimeter-long crystals. The conversion process takes less than a few nanoseconds. Some thousands of these photons successfully propagate through the crystal and strike a SiPM adhered to the crystal's rear face. This photodetector preserves the very fast nature of the incoming photon pulse and faithfully encodes it into an equally narrow charge pulse, which is finally digitized by electronics.

The collaboration performed a study at SLAC of a prototype array of 28 crystals read out by 16-channel large-area SiPMs. This electromagnetic calorimeter is a half-size prototype for one of the 24 stations that are required for the experiment. Analysis of the data indicates that the new design will handle the high rate at Fermilab and reduce the dreaded pile-up as planned.

To date, the detector team has received 500 of the 1,300 crystals needed and is continuing to prepare for the production of the custom SiPM boards and the overall mechanical housings and stands. The equipment will be shipped to Fermilab in spring 2016 and assembled here into the 24 stations that summer. The Muon g-2 experiment is scheduled to start running in early 2017.

The results of the beam test and associated R&D were recently submitted to NIM-A, the first technical publication for the new experiment.

David Hertzog and Jarek Kaspar, University of Washington

This group participated in the Muon g-2 calorimeter test beam run at SLAC.
These are the principal members of the Muon g-2 calorimeter team. From left: David Hertzog, Aaron Fienberg and Jarek Kaspar, all of the University of Washington.

Today's New Announcements

Getting paid the greener way - get paperless pay stubs

Managed print upgrade revised date - Jan. 25

Zumba Toning registration due Jan. 27

Linux User Group meets Jan. 28

Zumba Fitness registration due Jan. 29

Vaughan Athletic Center membership rates effective Feb. 3

Writing for Results: Email and More - Feb. 27

Fermilab Functions - March 3, 5, 11

Interpersonal Communication Skills course - March 10

Managing Conflict course - March 24

2015 FRA scholarship applications accepted until April 1

Windows 8.1 approved for use

GSA updates mileage rate to 57.5 cents for 2015

Abri Credit Union appreciates our members

The Take Five challenge and poster winter 2014/2015

Scottish country dancing Tuesday evenings at Kuhn Barn

Indoor soccer