Monday, Oct. 29, 2012

Have a safe day!

Monday, Oct. 29

2:30 p.m.
Particle Astrophysics Seminar - One West
Speaker: F. William High, University of Chicago
Title: Targeted Weak-Lensing Follow-Up of Galaxy Clusters in the South Pole Telescope Survey

3:30 p.m.


Tuesday, Oct. 30

3:30 p.m.


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Wilson Hall Cafe

Monday, Oct. 29

- Breakfast: apple cinnamon multi-grain pancakes
- Spicy Thai beef noodle soup
- Bayou tuna steak sandwich
- Chipotle lime glazed pork
- Smart cuisine: sweet and sour apricot chicken
- Asian chicken wrap
- Assorted pizza by the slice
- Stir fry sensations

Wilson Hall Cafe Menu

Chez Leon

Wednesday, Oct. 31
- Skeleton bones
- Frankenstein fingers
- Ghost clouds
- Dracula's dream

Friday, Nov. 2
- French onion soup
- Grilled swordfish with white wine
- Butter sauce with capers
- Corn risotto
- Sautéed pea pods with red peppers
- Almond cake

Chez Leon Menu
Call x3524 to make your reservation.


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Dark-matter seekers get help from the DarkSide

This dramatic shot shows the final stages of assembly of the 4-meter-diameter steel vessel, which will house the liquid scintillator and the low-radioactivity liquid-argon detector. Photo: Yuri Suvarov, UCLA

A treasure trove of dark-matter detectors rests within the deep reaches of Italy's Apennine Mountains as part of the Gran Sasso National Laboratory. The mountains shield them from cosmic rays, making these detectors highly sensitive to dark-matter particles.

Pushing the envelope for still higher sensitivity is the trove's newest jewel, the DarkSide-50 experiment, which is nearing the end of its construction. DS-50 will use 150 kilograms of low-radioactivity liquid argon, which Fermilab is helping to obtain, as target material for highly sought-after dark-matter candidates called weakly interacting massive particles, or WIMPs.

The mountains can't protect against all types of background contamination, one being radioactive decay from the materials of the apparatus – a major concern for dark-matter detectors like DS-50.

When a WIMP interacts with an argon nucleus, the nucleus will deposit the energy it is given in the argon, producing a flash of light and ionizing some of the argon atoms around it.

"Radioactive decays can mimic a WIMP because they deposit energy in the liquid that is close to the energy of interest," said Fermilab scientist Stephen Pordes, who works on the experiment.

In addition to using low-radioactive target material, the cryostat that will house the detector is made of low-radioactivity steel. Also, the air in the room where scientists are currently assembling the detector is free of radon, a radioactive element usually present in air that can stick to the materials.

DS-50 will be the world's first detector to use low-radioactivity liquid argon. Moreover, scientists are designing it to have some of the lowest rates of background events compared to similar detectors.

"The strategy we're following is to reduce the number of background events to less than 0.1 in three years," said Luca Grandi, a research associate at Princeton University. "That way, if we do get a bunch of events in the detector, it's a good bet that it will be WIMPs."

Next door to DS-50 is the ICARUS experiment, which includes the world's largest liquid-argon chamber used for detecting neutrino oscillations. The ICARUS detector holds 600 tons of liquid argon but, even if scientists were tempted to borrow some for DS-50, it would be of little use.

Read more

Jessica Orwig

Photo of the Day

Snapping turtle acceleration not so snappy

Last week AD employees Owen Marshall and James Santucci encountered a roughly 16-inch-wide snapping turtle in the middle of the street near Kirk Road. They helped the wayward turtle to the pond in front of Wilson Hall without being snapped at. Photo: Owen Marshall, AD
In the News

Orphaned stars linger in dark matter haloes

From New Scientist, Oct. 24, 2012

Outcast stars stripped away by galaxy mergers may be trapped in the cocoons of dark matter that surround galaxies. If so, these stars would explain seemingly random smatterings of light in the infrared sky, which should illuminate studies of how the first galaxies formed and grew.

The universe is permeated by faint infrared light called the cosmic infrared background radiation, thought to be a collective glow emitted by all the stars and galaxies in the universe. This splotchy haze contains strange fluctuations that can't be explained by known sources.

Previous research hinted that the odd pattern might be caused by the very first stars and galaxies in the universe or the light of nearby dwarf galaxies that are too faint to resolve. But that would mean the universe spawned many more galaxies than we can detect, which would create turmoil for current models of how the cosmos has evolved.

Now, a new infrared map from NASA's Spitzer Space Telescope shows that unseen galaxies are not the culprits. When the intensity of light from the mysterious splotches is measured against that of known galaxies, it simply doesn't match, says Matthew Ashby, an astrophysicist at Harvard University who is on the study team.

Read more

Tip of the Week:
Quality Assurance

Engineering quality at Fermilab

Engineering drawings were reviewed as part of the assessment. Image: PPD Mechanical Department

The Office of Quality and Best Practices is pleased to report that Fermilab's site-wide design and engineering assessment is now complete.

Between June and September 2012, OQBP, along with Division/Section/Center (D/S/C) quality assurance representatives, completed a series of design and engineering assessments, two of which were a combined effort with quality assurance staff from the DOE Chicago office. The assessments evaluated the implementation and effectiveness of quality assurance controls for design and engineering in several divisions and sections. Representatives conducted the assessments by interview, review of documentation and observation of project activity. In the course of the assessments, they interviewed 25 people and reviewed 37 projects.

The results show that three of the five D/S/Cs assessed met and effectively implemented the design and engineering requirements specified in the Integrated Quality Assurance document and the Fermilab Engineering Manual. The two remaining D/S/Cs partially met and/or partially implemented these requirements. There were no lab-wide findings and only two local findings were made:

  1. The requirements of the Fermilab Engineering Manual are not fully implemented in two of the organizations assessed. Risk assessments need to be completed correctly for all projects as it determines the appropriate level of formality as a project moves forward.
  2. Three projects assessed within one of the divisions did not have the required documentation for requirements or design reviews.

These are respectable results given the amount of engineering activity at Fermilab. Fermilab's design and engineering requirements can be found in Chapter 6 of the Integrated Quality Assurance document and the Fermilab Engineering Manual. Local D/S/C engineering procedures may also be available. Contact your quality assurance representatives to obtain a copy of these documents.

OQBP invites comments and suggested improvements to the Fermilab Engineering Manual, which will be shared with responsible engineering authorities.

Mike Pakan


Enrollment for 2013 benefits

Benefits enrollment will continue through Tuesday, Nov. 6. This is an active enrollment, which means that even if you intend to continue with the same plans and coverage that you have this year, you must re-enroll. If you do not re-enroll, your coverage will be suspended on Dec. 31, 2012.

Please complete your enrollment form and send it to the Benefits Office, mail stop 126, or fax it to 630-840-5207. Periodic active enrollments are necessary to ensure that beneficiaries and dependents are up to date.

For more information, visit


Today's New Announcements

Free resistance band classes offered

Yoga class - begins Oct. 30

Survey of God's promise through history - begins Oct. 30

Butts & Guts - begins Oct. 30, Nov. 1

"Playing with Time" at the Field Museum - register by Oct. 31

SciTech presents Masters of Lightning - Nov. 3

CSADay 2012 training opportunities - Nov. 6

Enrollment for 2013 benefits - through Nov. 6

LabView sessions - scheduled for Nov. 16

Deadline for UChicago Tuition Remission Program - Nov. 26

Calling all veterans 

2013 403(b) plan limitations

Abri Credit Union - money just got cheaper

Winter volleyball begins soon

Professional development courses

Atrium work updates