Grant: $555,076 - National Science Foundation - Aug. 8, 2009
44% voted satisfied - 56% voted not satisfied - 9 vote(s) cast
Award Description: Dr Gebhardt and his team will use a fiber-fed spectrograph at the McDonald 2.7-meter telescope to measure stellar motions in the outer parts of nearby elliptical galaxies. The large fibers will gather diffuse light over a 2-arcminute field of view, which reaches the outskirts of the target galaxy. These observations will be combined with detailed measurements in the central regions with the Hubble Space Telescope and with 10-meter ground-based telescopes using adaptive optics. The measured motions will be compared with both axisymmetric and triaxial orbit-based models, to place limits jointly on the distribution of dark matter and the mass of a central black hole. This team has already shown that these two quantities are difficult to measure independently, and that omitting the dark halo from models of the central galaxy yields too small a mass for the black hole. The team will concentrate on galaxies for which other mass measures, such as those from X-ray-emitting gas, or the motions of planetary nebulae or globular star clusters, are available for comparison. The computationally expensive modeling will be done at the Texas Advanced Computing Center. This award will support postdoctoral scholar Shen, a graduate student, and undergraduate researchers. As part of his NSF CAREER award AST-0349095, Dr Gebhardt built a web page, available both in English and in Spanish, to make his black hole research accessible to the public. He will maintain and develop this website, in association with StarDate magazine and the McDonald Observatory's visitor center.
Project Description: I have organized the overall structure of how to analyze the data that we are getting. We will proceed along two paths of working with axisymmetric and triaxial models of galaxies. This comparison will allow for the most robust measure of the galaxies' dark halo and black hole mass. I have also met with my web designer and we are currently working on a substantial upgrade of the webpage.
Jobs Summary: A research fellow is appointed 1.0 FTE. (Total jobs reported: 1)
Project Status: Less Than 50% Completed
This award's data was last updated on Aug. 8, 2009. Help expand these official descriptions using the wiki below.