Another cosmic-ray puzzle: Are iron nuclei bombarding Earth?

A fluorescence telescope (background) and a surface detector at Pierre Auger Observatory in Malargue, Argentina.

For decades, scientists have thought that the highest-energy cosmic rays-those packing up to a million trillion electronvolts-were almost exclusively protons. But data from the Pierre Auger Observatory in Argentina, the world's top facility dedicated to ultra-high-energy cosmic rays, could tell a startlingly different story. At the International Cosmic Ray Conference, held from July 7 to 15 in Lodz, Poland, Auger scientists are presenting data that raises the possibility that some of those super-speedy cosmic bullets could actually be iron nuclei.

"It would surprise a lot of people if some of these particles turned out to be iron," says Hank Glass, an Auger collaborator at Fermi National Accelerator Laboratory. While scientists can imagine mechanisms that would accelerate protons up to nearly the speed of light, they have no idea where ultra-energetic iron nuclei could originate.

"Then again," Glass adds, "nature is full of surprises."

Scientists at Auger combine two methods to investigate these mysterious extragalactic invaders. An array of 1600 water tanks, spread over 1200 square miles of Argentine grassland, acts as a giant particle detector, tracking the showers of secondary particles that high-energy cosmic rays generate when they hit air molecules in Earth's atmosphere. A set of fluorescence telescopes picks up the faint ultraviolet glow of those secondary particles interacting with atmospheric nitrogen. Merging data from both sources, scientists can determine the energy, trajectory, and-ideally-identity of the primary particles.

One telltale statistic is the altitude at which the cosmic rays interact. Based on data from human-made particle accelerators, theorists have developed models for the interactions of various particles in Earth's atmosphere. Protons, with their small mass, should penetrate relatively deeply before they start to shower. Heavier nuclei, like iron, should generate showers further from Earth's surface.

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-- Rachel Carr

Gov. signs $31 billion construction plan

From Daily Herald, July 13, 2009

Gov. Pat Quinn on Monday approved the state's first construction spending plan in over a decade - a $31 billion infusion expected to create thousands of jobs and help rebuild the state's crumbling infrastructure that will be paid for through new and higher taxes and a vast expansion of legalized gambling.

... Among suburban projects in the $31 billion capital spending program signed by Illinois Gov. Patrick Quinn on Monday:
$17 million to the Fermi National Accelerator Lab (Batavia) the Illinois Accelerator Research Center

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Tune IT Up taking stock of computing at Fermilab

As part of the Tune IT Up campaign, Fermilab Chief Information Officer Vicky White and Computing Division staff will collect basic data about the laptops, desktops and smart phones Fermilab employees and visitors use for their daily work.

Your part in this data collection will involve taking about five minutes to fill out an assessment form online. The form will ask for information about your location in the laboratory, what kind of machines and operating systems you use and whether your machine provides services to other users.

Each week, members of one division, section, center or experiment will receive the request to fill out their assessments, starting this week with the Technical Division. When it is your turn, the Service Desk will send you an e-mail message with information about how to fill out the form.

You can also reach the form at any time through the Tune IT Up Web site at www.fnal.gov/tuneitup.

The laboratory is taking this inventory to gather up-to-date information about the laptops, desktops and smart phones used to connect to the Fermilab network. Using this information will allow the laboratory to better support and protect computers and to ensure that systems are appropriately configured. The vulnerability of even one machine can cause a disruption across the entire laboratory. The assessment could bring to light security vulnerabilities that may not be obvious. For example, if your machine runs a Linux operating system, but you share Windows files, you will need to run both Linux and Windows antivirus software.

The Computing Division will also use the assessment to make sure each machine gets proper care, tailored to its type and function. "If your computer is running file shares, it should be treated as a file server, not a desktop," said Jack Schmidt of the Computing Division. Otherwise, it's like seeing a veterinarian to treat a cold or wearing a helmet to warm your hands.

Please submit questions about the assessment through the Tune IT Up Web site.