Sunday, June 14, 2009

Comps 2 reflections

Comps 2 included some successes and some failures.

The most successful part of my Comps preparation was the Monday talk. The previous talk on Tuesday was somewhat helpful in terms of realizing that I needed larger figure axes, but otherwise provided no useful feedback. The Monday talk allowed me to realize what needed to be done to make my talk accessible to a larger audience.

At the defense, I ended up going only ~40 minutes despite having gone far over time in the Monday version and spending ~5 minutes answering questions from Don and Mike. I think that was a good thing; I didn't need to say anything more even though there was an enormous amount of additional material I could have covered.

The main change I made from Monday to Friday was reorganizing such that I discussed the largest scales first and zoomed in, and I spent much more time discussing the larger context of my work. Unfortunately, I also spent most of the week before the presentation determining the larger context and reading papers. Ideally, I would have done that before handing in the paper.

The closed door Q&A section went OK but not great. There were a few important bits of information related to the IMF that I didn't know off the top of my head - e.g. the ratio of total # of stars to the # of B stars. I got the lowest mass star (.07) confused with the most common star mass (.3). I wasn't particularly able to integrated the IMF on the board either. I didn't remember the Jeans mass-temperature and mass-density relationships but was able to derive them quickly enough.

Probably the biggest problem was dealing with a question about the partition function - specifically how did the partition function come into play in the column density equation. I didn't come up with the right answer at all, and in particular quoted the wrong distribution. However, I think a big part of what they expected to hear was a dependence on temperature AND degeneracy, and I never explicitly mentioned degeneracy. It turned out that the equation I had quoted in both the paper and the talk was correct, but I couldn't come anywhere close to proving that on the spot.

My expected result is therefore a low pass, though it was not made explicit. That's rather unfortunate as it's possible that another month of preparation could have gotten me the high pass, but at the same time, it's well worth having the project done.

No comments: