Friday, July 16, 2010
❄ What Did I Learn in School Today?
Today I read Jonathan Medalias report Detection of Nuclear Weapons and Materials: Science, Technologies Observations. [Note 1] The report usefully reviews several programs to build systems that could identify nuclear or radiological material in a shipping container, a big steel box typically hoisted onto a container ship. There is an appendix explaining the bare minimum of physics facts needed to make sense of the report.
[•] I was introduced to muon tomography [p. 51 ff.]. Muons are produced by cosmic rays when they hit atoms in the upper atmosphere. Detection exploiting this fact is different from [a] sensing neutrons or gamma rays emitted by nuclear material, [b] directing x-rays at the suspect volume and sensing what happens, and [c] radiography (bombarding the suspect volume and looking for obstacles).
[•] My suspicions were confirmed. There is no method (August 2009) that meets all criteria: proven effective, cheap enough, small enough, discriminating what users want distinguished, providing rapid through movement of containers, no false negatives, few false positives, and actually can be built with present materials and industrial capacity. With work and time, performance will improve. In the final analysis, however, Systems to detect [uranium and plutonium] at close range, such as at ports and land border crossings, are generally not applicable to detection of terrorists smuggling a weapon across a remote stretch of border. But that is not a flaw of the detection system. [p. 77] Of course not.
[•] I learned there has been a series of reports, begun in 1994, listing declassified facts and terms concerning US nuclear weapons. [Note 2] Entries can be a bit cryptic, e.g. m. Fact of use of extrudable explosives in unspecified weapons. (67-1).” where (67-1) identifies the year and action of declassification.
[❄] And I read Jeffrey Lewis brief VERTIC Occasional Paper 4, on the CTBT. [Note 3] He has picked up on two bright ideas. He cites the Perry-Schlesinger Commission on the Strategic Posture of the United States that if the US Senate consented to CTBT ratification the United States should secure agreement among the P-5 to implement CTBT verification provisions without waiting for entry into force of the treaty and to agree to an effective process among the P-5 to permit on-site inspections. And, second, he writes
What happens, though, if the international community gets close to entry into force but still faces one or two obstinate hold-outs? One proposal—initially controversial, but slowly gaining traction—is the provisional application of the treaty pending its full ratification by all.
[Note 1] Jonathan Medalias report Detection of Nuclear Weapons and Materials: Science, Technologies Observations. US Congress. Congressional Research Service. R40154. 4 August 2009. 96 pp. Medalias title is Specialist in Nuclear Weapons Policy.
[Note 2] US Department of Energy. Office of Declassification. Drawing Back the Curtain of Secrecy: Restricted Data Declassification Policy, 1946 to the Present, RDD-1, 1 June 1994. https://www.osti.gov/opennet/forms.jsp?formurl=document/rdd-1/drwcrta.html#ZZ0 And more recently: U.S. Department of Energy, Office of Declassification, Restricted Data Declassification Policy 1946 to the Present (RDD-7), January 1, 2001, available at the internet at: http://www.fas.org/sgp/othergov/doe/rdd-7.html ;
RDD-8, 1 January 2002: http://www.fas.org/sgp/othergov/doe/rdd-8.pdf
[Note 3] Jeffrey Lewis, The CTBT: Prospects for Entry Into Force,” VERTIC Occasional Paper 4, June 2010.
[Bruce Larkins Blog 2010.07.16. Post B05. Short Link: p=20. Front Door Index: http://blog.learnworld.com/ Permalink: http://www.learnworld.com/BRUCE/uncategorized/❄-what-did-i-l…n-school-today/]