Sep. 2

"Hot Chromospheres and Flares on Cool and Ultracool Dwarfs"

Cool (M) and ultracool (late-M and L) dwarfs include both the least massive stars and warmest brown dwarfs. While their photospheres are characterized by cool (or ultracool) temperatures, the presence of strong surface magnetic fields on many of these objects results in hot chromospheres. On these M and L dwarfs, hot chromospheres are traced by both Halpha emission (in quiescence) and dramatic multi-wavelength flare events. Using detections of Halpha in spectroscopic data primarily from the Sloan Digital Sky Survey, I will examine the changing relationship between activity and age over the M/L spectral sequence. The combination of the strength of these detections with one-dimensional chromosphere models reveals strong changes in the chromospheric heating over the same range of spectral types. I will also discuss the limited flare detections on ultracool dwarfs, placing them in the context of flare observations on cool (early- to mid-M) dwarfs. Flares may prove to be a powerful age indicator in future multi-epoch surveys.

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Sarah Jane Schmidt

Ohio State University

host: Adam Kraus

Sep. 9

"Let it Collide: An Epic Saga of Star Wars Planets, Planetesimals, and Super Planet Crashes"

abstract

Stefano Meschiari

University of Texas at Austin

host: Adam Kraus

Sep. 16

"The Complex Interplay between Star Formation and Galaxy Evolution from z~0-6"

abstract

Desika Narayanan

Haverford College

host: Steve Finkelstein

Sep. 23

"Compact Galaxies and Super-Massive Black Holes"

abstract

Remco van den Bosch

Max Planck Institute for Astronomy (MPIA), Heidelberg

host: Karl Gebhardt

Sep. 30

"The Architecture and Timing of Planetary Systems"

abstract

Daniel Fabrycky

University of Chicago

host: TBD

Oct. 7

"Who's Afraid of the Big Bad Supermassive Black Hole?"

abstract

Jonathan Trump

Pennsylvania State University

host: Steve Finkelstein

Oct. 14

"Puzzles in the Structure of Disk Galaxies"

abstract

Stephane Courteau

Queen's University, Kingston, Ontario, Canada

host: Karl Gebhardt

Oct. 21

"Galaxy Build-up in the First Gyr: Insights from ultra-deep HST and Spitzer Observations"

abstract

Pascal Oesch

Yale University

host: Steve Finkelstein

Oct. 28

"Forming Earths and Mercuries: Solids Less Volatile than Ice"

abstract

Alexander Hubbard

American Museum of Natural History, New York

host: Joel Green

Nov. 4

"Shedding Lyman Alpha Light on Cosmological Reionization"

abstract

James Rhoads

Arizona State University

host: Steve Finkelstein

Nov. 11

"From Disks to Planets: Observational Insights"

abstract

Andrea Isella

Rice University

host: Adam Kraus

Nov. 18

"The Giant Magellan Telescope Project: Science and Status"

abstract

Rebecca Bernstein

Giant Magellan Telescope (GMT)

host: Taft Armandroff

Nov. 25

"There's Government in Your Science"

abstract

Joshua H. Shiode

American Astronomical Society

host: Jeff Silverman

Dec. 2
3.30 PM
RLM 15.216B

DeVaucouleurs Medalist

DeVaucouleurs Lecture: "The Growth of Supermassive Black Holes and Galaxy Evolution"

abstract

C. Megan Urry

Yale University

dinner host: Shardha Jogee (Medal Awarded by Daniel Jaffe)

Dec. 3
4 PM
ECJ 1.202

DeVaucouleurs Medalist

Public Lecture: "Black Holes, Galaxies and the Evolution of the Universe: An Observer's View"

abstract

C. Megan Urry

Yale University

dinner host: Daniel Jaffe

Dec. 4
4 PM
NHB 1.720

DeVaucouleurs Medalist

UT CNS Women in Science Lecture: "Why So Few? The Dearth of Women in Science"

abstract

C. Megan Urry

Yale University

dinner host: Dean Linda Hicke

Dec. 9

"Brown Dwarfs as Exoplanet Analogs"

abstract

Katelyn Allers

Bucknell University, Lewisburg PA

host: Adam Kraus