We're doing something rather ambitious and, for the moment, it's working. Usually to perform our experiments we need to run at the synchrotron. However, we have our own x-ray source in our lab. It's dismally dim compared to the synchrotron, but it's ours. And as far as rotating anode x-ray sources are concerned, it's actually not too shabby. Our goal : successful surface scattering from our rotating anode.

We've had a huge number of problems in this process. I'd hoped to start taking data on Saturday, however it wasn't until today that we actually got really started. In all honesty, the solution to our final problem turned out to be double-sticky tape. Don't ask.

And so... here it is :



The smallish bump on the left indicates a well ordered surface, though it doesn't tell us exactly what the surface is. The bump on the right is a little more important. The only reason it should be there, and so strong, is if there is a hexagonal surface layer of gold on top. The fact that we're able to get both signals at once, from our little rotating anode x-ray machine, is very nice. The fact that we've got it will let us do further experiments without actually having to go to the Advanced Photon Source (well, as much).

In order to get this signal we have to run our machine at full power (12 kWatts), optimize all the positions and slits to minimize noise, flood the entire beampath with Helium gas to cut down on parasitic air scattering, and more. And of course... we've got to have a reasonably well prepared sample in the first place. The fact that we're using gold, where each atom has a large number of electrons, also helps us a great deal.