I just got back from a month at UT Austin as a visiting Tinsley Scholar, which was great. Two years ago I went for three months as a Tinsley Professor, and got to bring part of my research group with me, but this time was a smaller scale visit. I started two projects that I had been discussing for awhile, but now these have (I hope) legs. One is together with Prof. John Kormendy, and is being led by my former postdoc Dr. Rich Plotkin, now a senior fellow at Curtin University in Perth, Australia, and also includes Dr. James Miller-Jones, from the same institute. This paper involves a relationship I helped discover called “the Fundamental Plane of Black Hole Accretion” (see, e.g., Merloni, Heinz & Di Matteo 2003; Falcke, Körding & Markoff 2004; Körding et al. 2006 and Plotkin et al. 2012, if you are interested in more details). Basically if you make a three dimensional space where each axis represents, respectively, radio luminosity, X-ray luminosity and black hole mass, almost all black holes we know of that have compact jets lie on a two-dimensional plane in that space. This relationship gives us clues about how black holes release energy into different forms, and the coupling between what goes in and what goes out, so is very important to understand how black holes potentially impact their surroundings. It also tells us that black holes operate in “modes” that care more about the rate at which they are fed material than what their mass is. In other words, a black hole of a few solar masses will regulate its power output similarly to a supermassive black hole, as long as they are at a similar relative power (we can scale the power in a way that is independent of mass).
However there is some scatter in this relationship that we would like to understand better and, if possible, decrease. Also, people are increasingly using this relationship to determine the mass of newly discovered black hole candidates given observations of their radio and X-ray luminosities, in particular for objects that could be the hard-to-find intermediate mass black holes. But, the way we found the original Fundamental Plane was not actually well-adapted for this purpose. What we would like to do is a new study of the relation, using updated masses from Prof. Kormendy and collaborators, and then perform the statistics of deriving the plane relation in a way that the community can also use to find unknown masses.
The other project is with Prof. Volker Bromm, who is an expert in simulating stellar populations and feedback in the early universe. We are starting to think about how to better include the effects of early black holes in these simulations, particularly in terms of the accretion modeling. Most simulations just assume a fixed efficiency of heat dumped into the grid by a given black hole, and we are curious if better implementations of the physics will actually change the net result in the simulations.
But I digress…the main point of this post was that while I was gone, I found out that I had been promoted officially to full professor as of 28 February! This is a really nice thing, first of all because it means I get to wear a funny hat and robe (“toga”) at my students’ graduations! But more seriously, it means that in the byzantine Dutch system I can now be credited as the sole supervisor of my Phd students, while until now I had to have someone else who was full professor sign off as a formality. And it means I become one of just five (or six??) female professors at my university’s science faculty, something like 4% I guess. This number is still really low, even compared to other science faculties in the Netherlands, but it is slowly changing.
So anyway, sometime in the fall is an official ceremony called an “oratie” where I will give a public-level talk and there will be some kind of party after, stay tuned!
