Thursday, Oct. 1, 2015
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Scheduling a meeting with the Visa Office

FSPA officer elections open today

English country dancing Oct. 4 and 25 at Kuhn Barn and special workshop Oct. 15

NALWO evening social - Oct. 7

Process Piping Design; Process Piping, Material, Fabrication, Examination, Testing - Oct. 13, 14, 15, 16

Python Programming Basics - Oct. 14, 15, 16

Interpersonal Communication Skills - Oct. 20

Access 2013: Level 2 / Intermediate - Oct. 21

Excel 2013: Level 2 / Intermediate - Oct. 22

Managing Conflict (morning only) - Nov. 4

PowerPoint 2013: Introduction / Intermediate - Nov. 18

Python Programming Advanced - Dec. 9, 10, 11

Professional and Organization Development 2015-16 fall/winter course schedule

Outdoor soccer

Scottish country dancing Tuesdays evenings at Kuhn Barn

International folk dancing Thursday evenings at Kuhn Barn

Norris Recreation Center employee discount

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Video of the Day

PXIE RFQ arrives at Fermilab

Fermilab develops cutting-edge accelerator technology that can deliver the powerful, intense beams needed to study neutrinos and new physics. A crucial piece of the laboratory's advanced accelerator R&D program, the PXIE RFQ, recently arrived at the laboratory. Fermilab is now one step closer to building a test bed for future accelerator technologies. View the 2-minute video. Video: Fermilab
In Brief

Now accepting applications for Fermilab-University of Chicago full-time scholarship

Children of full-time, regular Fermilab employees are eligible to receive full tuition scholarships at the University of Chicago. One scholarship is awarded each year. Scholarship recipients will continue to be eligible for annual renewal as long as they remain in good academic standing and the recipient's parent remains a full-time employee of Fermilab. The university will also continue to provide one-half tuition remission to all dependent children who are admitted for study in the college or the laboratory schools of the university as long as the recipient's parent remains a full-time, regular Fermilab employee.

To be awarded the full-time scholarship, the student must be accepted for first-year admission to the University of Chicago and must be among the most qualified applicants from Fermilab families as judged by the admissions committee. First-year applicants are required to complete either the Universal Application or the Common Application, both available online. Additionally, students will be required to complete the University of Chicago Supplement, which is available online or through the Common Application. The deadline for applications to the University of Chicago is Nov. 1, 2015, for early action and Jan. 1, 2016, for regular decision.

Students who wish to compete for the Fermilab-University of Chicago full-time scholarship are required to complete a Fermilab verification form. The deadline for submitting this form is Dec. 2, 2015. Scholarship recipients will be announced by April 1, 2016, and must accept or decline the offer no later than May 1, 2016.

These are merit-based scholarships and do not preclude the possibility of additional need-based financial assistance from the university. The university strives to ensure that financial need is not the controlling factor in determining whether a student can attend. To apply for financial aid, complete the UChicago Financial Aid Worksheet, which is due Nov. 1, 2015, for early action applicants. The Free Application for Federal Student Aid must be filed with the appropriate processing agencies by Feb. 1, 2016, for regular notification. For additional information, please visit the university's admission Web page.

For information on admissions, please contact Emily Benoit, assistant director of admissions, by email or at 773-702-7944.

Milestone

Final Force, Fermilab Co-ed Softball League champions

The Final Force are this year's softball champs. Thanks go to Dan Johnson, AD, for providing the "old red hats" in honor of Bob Kingsley, a founding and long-time teammate who recently passed. Thanks also to Flat Dave for standing in for team captain Dave Hockin, ESH&Q, affectionately known as Goat Man, while he's recovering from planned surgery. Photo courtesy of Chris Greer, ESH&Q

Final Force are the 2015 champions of the Fermilab Co-ed Softball League. Kudos go to all the league's teams for an excellent season: Big Bangers, Boomers, Final Force, Lightning Rods and Prairie Fire.

Photo of the Day

Sunrise over the berm

nature, sky, sunrise, sun
The sun rises near AZero, reflecting off a car roof. Photo: David Huffman, PPD
In the News

Fermilab's giant magnet is ready to go

From Popular Mechanics, Sept. 24, 2015

‚ÄčThe Muon g-2 was set to be a crown jewel at Illinois' Fermilab. But first, it had to arrive safely with almost no margin of error. If it bent the slightest bit, the $25 million magnet would be of no use in discovering the mysteries of the universe.

‚ÄčThe magnet previously was sitting around gathering dust at Brookhaven National Laboratory in New York. But Fermilab opted to take it on in order to research follow-up resorts from the second round of Large Hadron Collider experiments. The 52-foot magnet was a behemoth to haul, eventually arriving in Illinois via barge on a journey that took it from New York to Florida to the Gulf of Mexico and upstream to its new home just outside Chicago.

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Physics in a Nutshell

Linear accelerators for injection

Injecting into the Booster: Negative ions are injected into the Booster from the Linac (red path). Immediately after they exit the magnet, a stripping foil removes the electrons from the ions, leaving only protons, which circulate in the Booster (blue path). After completing one trip around the Booster, they are joined by more negative ions arriving from the Linac, which are likewise stripped of electrons to become protons, which in turn go around the Booster.

Today I would like to go all the way back to my first column, in which I discussed stringing batteries in a row to create a large enough electric field to be interesting for particle physics. We quickly decided that batteries were not a practical solution. However, it is also not practical to inject beam from a very low-energy particle source directly into even a modest-energy synchrotron. The problem arises because the beam size is too large, and it increases rapidly at low energies since the individual particles in a bunch repel one another. At high energies this effect is not so noticeable since the beam's longitudinal velocities are much greater than the transverse velocities. One solution to get from our low-energy particle source to a synchrotron is to go through a linear accelerator, or linac, first.

At Fermilab we initially inject beam from a negative ion source into something called a radio-frequency quadrupole. The RFQ accelerates the ions to 750 thousand electronvolts, or eV, while keeping them focused. Next, the ions pass through Fermilab's linear accelerator, or Linac. Traveling down the Linac, the ions' energy increases by a factor of more than 500 — to 400 million eV, which is the energy they need to be injected into the next part of the accelerator chain, the 8 billion-eV Booster, a circular accelerator or synchrotron.

As the negative ions enter the Booster, they pass through an injection magnet followed immediately by a thin stripping foil that removes the electrons from the negative ions (see illustration above), leaving only protons, which then go on to circulate through the Booster. (Protons are sent to targets to make beams for experiments or are sent directly to the experiments.) Using negative ions at the point of injection to the Booster allows us to inject 10 or more turns into the Booster for each acceleration cycle, thus enabling higher intensity per Booster cycle.

From the Booster, beam is sent into the Recycler and then on to the Main Injector, which accelerates the beam and before sending it to Fermilab's various experiments.

The upstream half of the Fermilab Linac consists of large RF cavities, or tanks, with copper drift tubes inside along the center line of the cavities (see illustration below). The cavity resonates at 201 megahertz (MHz). The beam passes through a hole in the center of the drift tubes and experiences the accelerating field when it is in the gaps between drift tubes. In order to maintain synchronization between the beam and the oscillating field, each successive drift tube is longer than the previous one. This ensures that the beam is in the gap only when there is an accelerating field present. The process gets the beam up to 116.5 million eV.

The downstream end of the Linac has side-coupled RF cavities that oscillate at a frequency of 805 MHz. They are much more efficient in their use of linear space than the drift tube arrangement, resulting in a 400 million-eV beam energy for injection into the Booster.

Efficient Booster operation requires a gap in the beam to allow the extraction kickers to turn on without spraying beam into the Booster magnets. Removing ions to create this gap inevitably leads to residual radioactivity. However, the residual activity can be minimized by by implementing this procedure as early in the acceleration process as possible: the lower the beam energy, the lower the residual activity. Currently this process is being implemented just downstream of the RFQ. This will facilitate making more intense beam for the neutrino program and other experiments.

This column along with the previous columns I have written completes an overview of the Fermilab accelerator complex. When the proposed PIP-II accelerator is complete, the entire linac will be replaced by a linac that uses superconducting RF cavities.

Roger Dixon

Drift tubes are lined up end-to-end inside part of the Fermilab Linac. Beam passes through a hole in the center of the drift tubes and experiences the accelerating field in the gaps between drift tubes. 'E' indicates the direction of the electric field, which propels the particles forward. 'B' indicates the direction of the magnetic field, which focuses the beam.
In the News

X-ray signal from outer space points to dark matter

From Science, Sept. 25, 2015

For years, high-energy radiation from space has been teasing scientists with inconclusive hints of dark matter. But a definitive answer may be at hand. A team of physicists says that certain galactic x-rays could be a sign of decaying dark matter, and that an upcoming satellite mission should prove or disprove their claim.

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