Astronomy Colloquium: Magellan/MDM Colloquium: Department Members Share Their Current Work Using Magellan/MDM Observatories

This week is the annual MDM & Magellan Colloquium, a series of short talks by Prof. Nuria Calvet, graduate student Marina Kounkel, and Prof. Keren Sharon, who use the University's optical telescopes and will talk about the results. The talk descriptions appear below.

Speaker: Nuria Calvet
Title: Disk and accretion evolution in the Orion OB1 association

The Orion OB1 association hosts populations spanning ages between 1 and 10 Myrs, the age range in which planets form. We have been carrying out a study of these populations that includes (1) discovering the low and intermediate mass members, (2) finding and characterizing the properties of their protoplanetary disks, (3) measuring the mass accretion rates of these disks and determining its evolution. I will describe how we have used an assortment of instruments in the MDM and Magellan observatories, including MIKE, MagE, and M2FS in Magellan, and CCDS and OSMOS in MDM, to carry out these studies.

Speaker: Marina Kounkel
Title: Kinematics in the Orion Complex

Previous studies of the kinematics of young stars in the Orion Nebula showed that, while most of the stars follow the velocity structure seen in the dense gas out of which they formed, a significant number of stars exhibit blueshifts on a few km/s with respect to the main population. The magnitude of the blueshifts is significant, as it sufficient for these stars to be gravitationally unbound from the cluster.  We obtained high resolution optical spectra using M2FS centered at Halpha and Li I lines in order to confirm the membership of this blue-shifted population and what it could imply in terms of the overarching structure. In addition, we look at NGC 2024, a nearby young cluster that is also a part of the Orion Complex, in order to obtain radial velocities of its stellar population.

Speaker: Keren Sharon
Title: A multiwavelength mass estimate of RCS2327, an extremely massive galaxy cluster at z=0.7