Yesterday, armed with my trusty little Canon G11, I took a day out of my family visit in Indiana and drove to Argonne National Laboratory to spend the day with Bob Smither, the physicist I’m working with on the gamma camera we hope will be able to image the da Vinci painting (There is actually more than one gamma camera design possibility now, but I won’t go into that in this post). Here is my little photo field-trip:
(Below) In his lab: The big cylindrical shiny thing on the left is the housing of a gamma camera, perhaps one of the models we’ll end up using for the imaging in the Hall of 500.
(Below) Another view of the gamma camera Smither invented. The copper crystal lens is placed in the center of the structure, the Germanium crystal detector would be positioned at the top end of the cylinder, and the aperture is where his hand is on the bottom. The copper crystal lens would go into the center of the housing, positioned to diffract the particular gamma ray being sought at an angle that would redirect it toward the Ge detector in the back. The result is a low background noise device that collects a large number of gamma rays from a small point. The image would be accrued through a scanning process.
(Below) A gamma ray lens on Smither’s desk. This may or may not be the kind we will use. There are two discs with bits of copper crystal (copper specially grown as a crystal) arranged in a way that, with the two layers are on top of each other, fill the gaps between the rings of the other disc to diffract most of the gamma rays that pass through it.
(Below) Another experiment he’s working on, a small part of a larger NIST experiment (National Institute of Standards and Technology) to measure the electric dipole moment of a neutron, in part using crystal diffraction. The bigger project, if successful, has Nobel potential. The silver cylinder on the right is a Ge detector, similar to the one we will use to look for gamma ray evidence of Leonardo’s paints–the main difference being we would need one that is electrically cooled rather than nitrogen cooled as this one is. Naturally, the electrically cooled model is significantly more expensive.
Afterward we had dinner with his wife Carol, who make an excellent chicken mole, and spent the evening discussing the project, kicking around thoughts on what the gamma rays coming out of the east wall of the Hall of 500 might someday reveal.