oreilly.com — Online Catalog: Palm and Treo Hacks, First Edition: “Written for beginning to experienced Palm users, Palm and Treo Hacks is full of practical, ingenious tips and tricks you can apply immediately. Whether you’re looking to master the built-in applications or you want to trick out your Palm to its fullest
extent, this book will show you how to get it .”

This is that rare O’Reilly book that I will dismiss out of hand. As a product developer at LexisNexis I correctly predicted four years ago that Pocket PC would surpass the Palm OS … but they wouldn’t listen to me. “Palm is so dominant, blah, blah, blah…”

Of course, “they wouldn’t listen to me” is lame … I’ve learned better since, or, more accurately, I’ve learned how to put myself in a position where I can greenlight myself.

The New Scientist reports:

The number of false positives [in current container scanning technology] may be reduced by a new set of detectors known as the Advanced Spectroscopic Portal, to be introduced in 2006. These will distinguish between radioactive isotopes such as plutonium and the potassium-40 in bananas by replacing the plastic scintillator with an inorganic crystal such as sodium iodide. These crystals also emit photons when hit by gamma rays, but the photons have different, clearly defined energies depending on which isotope the gamma rays come from, allowing the isotope’s identification.

But even this detector will not be able to detect uranium. So the DHS is devoting further millions to fund the development and testing of a new generation of active screening technologies that bombard containers with high-energy particles or rays and then scan for the resulting signature emissions. Instead of relying on the low-energy gamma rays that uranium naturally emits, the bombardment will spark the emission of higher-energy neutrons or gamma rays that can penetrate lead shields and be picked up by the detectors.

One idea being tested by Dennis Slaughter at Lawrence Livermore National Laboratory in California is to bombard the container with a beam of neutrons (New Scientist, 16 July, p 8). If the neutrons hit uranium or plutonium, they induce fission reactions that split the nuclei into smaller fragments, but do not start a chain reaction as the density of neutrons is too low. These fragments emit high-energy gamma rays as they decay.

Meanwhile James Jones of Idaho National Laboratory in Idaho Falls is using a similar idea in reverse. He bombards the containers with high-energy X-rays to induce fission reactions in uranium and plutonium and then looks for the neutrons that are emitted in the process (New Scientist, 11 January 2003, p 17).

Both these technologies have been used to detect HEU behind lead shields and have been developed to prototype stage. But both have their drawbacks. Neutrons are scattered by materials rich in hydrogen, such as food, fuel, clothes and wood. As a result, the illuminating beam in Slaughter’s system was unable to get to the sample in tests on cargoes containing any of these common materials, and the signature emissions of Jones’s technology could not pass out of the container.

Both have come up with methods to overcome this problem (see “Fission or food?”), but others think that since much of the freight passing through ports every day contains hydrogen-rich material, the answer lies not in neutrons but in photons. “Photons are much more penetrating of hydrogenous materials,” says physicist William Bertozzi at the Massachusetts Institute of Technology.

This is the state of the technology on the open record.

The New Scientist reports:

The number of false positives [in current container scanning technology] may be reduced by a new set of detectors known as the Advanced Spectroscopic Portal, to be introduced in 2006. These will distinguish between radioactive isotopes such as plutonium and the potassium-40 in bananas by replacing the plastic scintillator with an inorganic crystal such as sodium iodide. These crystals also emit photons when hit by gamma rays, but the photons have different, clearly defined energies depending on which isotope the gamma rays come from, allowing the isotope’s identification.

But even this detector will not be able to detect uranium. So the DHS is devoting further millions to fund the development and testing of a new generation of active screening technologies that bombard containers with high-energy particles or rays and then scan for the resulting signature emissions. Instead of relying on the low-energy gamma rays that uranium naturally emits, the bombardment will spark the emission of higher-energy neutrons or gamma rays that can penetrate lead shields and be picked up by the detectors.

One idea being tested by Dennis Slaughter at Lawrence Livermore National Laboratory in California is to bombard the container with a beam of neutrons (New Scientist, 16 July, p 8). If the neutrons hit uranium or plutonium, they induce fission reactions that split the nuclei into smaller fragments, but do not start a chain reaction as the density of neutrons is too low. These fragments emit high-energy gamma rays as they decay.

Meanwhile James Jones of Idaho National Laboratory in Idaho Falls is using a similar idea in reverse. He bombards the containers with high-energy X-rays to induce fission reactions in uranium and plutonium and then looks for the neutrons that are emitted in the process (New Scientist, 11 January 2003, p 17).

Both these technologies have been used to detect HEU behind lead shields and have been developed to prototype stage. But both have their drawbacks. Neutrons are scattered by materials rich in hydrogen, such as food, fuel, clothes and wood. As a result, the illuminating beam in Slaughter’s system was unable to get to the sample in tests on cargoes containing any of these common materials, and the signature emissions of Jones’s technology could not pass out of the container.

Both have come up with methods to overcome this problem (see “Fission or food?”), but others think that since much of the freight passing through ports every day contains hydrogen-rich material, the answer lies not in neutrons but in photons. “Photons are much more penetrating of hydrogenous materials,” says physicist William Bertozzi at the Massachusetts Institute of Technology.

This is the state of the technology on the open record.

–
Posted by wfzimmerman to Proliferated at 10/20/2005 11:51:00 AM