Sunday, March 21, 2010

March Meeting wrap-up

The March Meeting is over, and overall it was good, as usual, and far too large, as usual.  Clearly the favorite topics this year were topological insulators, graphene, and iron pnictide superconductors.  On Thursday I did see a very good invited session on scanned probe microscopy, including examinations of vortices in the iron pnictides (among other things) and careful measurements of spin excitations at the atomic scale (that last being a substitute talk by Prof. Hla of Ohio University).  I had good discussions with colleagues from other places, got some good ideas for different experimental techniques, and looked at all the gadgets being hawked by vendors.  Clearly the era of the cryogen-free dilution refrigerator is upon us, if you can actually get any 3He, have a spare couple of hundred thousand dollars, and can support a 6-10 kW compressor.  I was disappointed by turnout at an invited session that I'd helped organize (more in a separate post), but it was up against a session with talks by three Nobel laureates.  On the return flight, I had a fun time talking with the neighboring passenger, the drummer for Ra Ra Riot, on his way to a gig in Austin.  Good to be home, though.

3 comments:

Uncle Al said...

cryogen-free dilution refrigerator is upon us

http://blogs.physicstoday.org/newspicks/2009/11/helium-shortage-slows-nuclear.html

Homeland Severity spent $230 million on technology to detect smuggled nukes. The new machines are not deployed because Homeland Severity drained the US of helium-3 and it wasn't nearly enough.

The bottom center container (well below the Plimsoll Line) of a Panamax container ship holds a 2 kiloton "stolen" nuclear field munition (or a stateless 20 kt jury rig). It cruises into the Port of Tacoma, Los Angeles, Long Beach, Houston, Baltimore, Philadelphia, New York, Boston... and detonates. Swaddle the device in borax. What was there to detect behind water, steel, and boron - alpha, beta, gamma, or neutron?

http://www.mazepath.com/uncleal/drsteel4.jpg
United States Secretary of Homeland Severity Janet Napolitano, afterward.

Doug Natelson said...

Al, you do have a point. A nuke inside a thick lead shell would be hard to find. Do you think that means that we should not look for illicit radioactive materials at all? Let's keep the human toll out of this and speak purely in terms of economics. The minimal nuclear terror incident (e.g., a dirty bomb in a major city) is likely to cost billions in terms of lost productivity and cleanup. What is a reasonable level of expense, in your opinion, to try and detect such a weapon before its use?

Uncle Al said...

Borated microchannel plate amplifier in a night vision rig. It will detect and image. Was that so hard?

Jimmy Carter's deeply tunneled nuclear launch railway under the entire American southwest: Spy satellites a hundred miles up could see emissions through unlimited mass/cm^2 to target a first strike. Mount said technology in shopping carts and have the homeless push them around the docks.

Doug, never plug the broad end of a funnel. End Homeland Severity. All honest citizens get a concealed carry permit and petty crime vanishes. As for dropping a plane or melting one of our cities,

http://www.youtube.com/watch?v=INfZPrVFky4

Ablate the enemy and all his works. You'll never see that He-3 again. It was a blood sacrifice to the manbearpig.