The Disk Revealed: Part 2
Back in February I posted an image showing the outline of the disk:
but after talking with Aaron about his recent visit to Tufts, I realized that I didn't actually explain what was in the image. So I thought I would take a moment and put up a different graphic:
This one is from my 2010 Seattle AAS poster (biblographic reference is here, a copy of the poster can be downloaded from here). Basically I took the position implied by the orbit and put the center of the reconstructed images at that position. Then I tweaked the figure slightly (because the orbit isn't exactly right) and, through the magic of GIMP, flattened the image. Essentially I've let the F-star slide behind the disk, revealing it's silhouette. Since I made this graphic we obtained two additional epochs. One in Jan 2011 and the last in Apr. 2011, about 10 days after egress started.
Now I'm going to say that the bottom figure is incorrect. There's an obvious geometrical problem (where is mid-eclipse? See Dr. Bob's blog posts) that tells us that the disk is actually highly asymmetric, with as much as a 2/3 reduction in length on the trailing edge from what we would expect. Also, looking at the light curve we can also tell something about the trailing edge of the disk compared to the leading edge (what might that be?). I'll leave it up to you all to discuss what I've seen in the data.