Series: Astronomy Colloquium
Date: Wednesday 26-Apr-2017
Time: 16:05-17:00 (4:05-5:00 pm)
Location: CSS 2400
Speaker: Dr. Pieter van Dokkum (Yale University)
Title: "Exploring the low surface brightness sky with the Dragonfly Telephoto Array"
The talk will describe a new telescope concept, optimized for low surface brightness imaging. The Dragonfly Telephoto Array consists of 48 high-end telephoto lenses, creating the equivalent of an f/0.4 refractor with a 1m aperture. Early results from Dragonfly include a measurement of the stellar halos around nearby spiral galaxies down to ~32 mag/arcsec^2 and the identification of new satellite galaxies. Perhaps the most spectacular result so far is the discovery of a population of Milky Way-sized, very low surface brightness galaxies in rich clusters. A follow-up study of one of these "Ultra Diffuse Galaxies" shows that it is massive and extremely dark matter dominated, with a dark matter fraction of 98% inside its effective radius.
Colloquia are usually preceded by espresso and ice cream at 1:45 pm outside room PSC 1150 and are followed by an informal reception at 5:15 pm in that room. Anyone interested in talking with the speaker, or being added to the colloquium announcement email list, should contact the colloquium organizer. Lunch will normally be reserved for the speaker to talk to graduate students.
Prof. Stuart Vogel
Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.