Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors

Details Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors

Jan 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010aas...21532104y&link_type=abstract

American Astronomical Society, AAS Meeting #215, #321.04; Bulletin of the American Astronomical Society, Vol. 42, p.322

Physics

Optics

Scientific paper

The center of our Galaxy harbors a supermassive black hole, as well as a collection of young stars whose presence so close to the black hole is still a mystery. Observations of the stellar dynamics of this population will allow us to understand how and where these stars formed. As astrometric measurements of stars at the Galactic center are currently limited by systematics, we have produced a more accurate model for the optical distortions imposed on imaging data obtained at the Keck Observatory using the Laser Guide Star Adaptive Optics system (LGS AO/NIRC2; 2004-2009) and the speckle imaging system (NIRC; 1995-2005). Distortions from both the camera optics and the atmosphere impact the data at the level of a few mas, which is most clearly detected with the LGS AO data, due to its order of magnitude better centroiding accuracy compared to the speckle imaging data (0.1 vs 1 mas). Our work improves the absolute astrometry at the Galactic center by an order of magnitude. While the relative astrometry is also improved, it is a much less prominent effect as our observational approach minimizes the impact of static systematics on relative astrometry. With these improvements, we have, for the first time, pushed out the radius to which we can estimate a complete set of Keplerian orbital parameters beyond 1", which corresponds to the inner radius of the young stellar disk at the Galactic center, without a-priori assumptions (in particular disk membership). This allows us to place better constraints on the eccentricity distribution of the young stars, which is an important handle for formation and evolution scenarios for these perplexing objects. Similarly, these measurements allow us to directly probe the structure of the older, presumably relaxed population of stars, for which number counts suggest no central cusp.

Affiliated with

Also associated with

No associations

Rating

Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pushing Orbital Parameter Estimates of the Young Stars at the Galactic Center to Larger Radii by Improving Models of Systematic Errors will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-961854