Past Events

2020

Special A&A Colloquium: Danielle Berg (Ohio State University)

3:30–4:30 pm ERC 161

Bridging Galaxy Evolution Across Cosmic Time: Tracing the Interplay between Massive Stars and the Interstellar Medium with Spectroscopy

The first stars and galaxies initiated the epoch of reionization (EoR) and provided the seeds from which all galaxy evolution grew. Knowledge of the properties of these galaxies are needed to understand ionizing photon production and escape, and will provide the crucial missing link needed to weave a coherent picture of galaxy evolution. I will present several programs that are establishing the needed framework to interpret the spectra of galaxies from z~0‒10, bridging the present-day and early universe. These programs use multi-wavelength spectroscopy to disentangle the spectral signatures that characterize the interplay between massive stars and their surroundings, and allow us to interpret how radiative processes shape galaxies. I will show how precise measures of the stellar and nebular properties of both nearby and distant lensed galaxies directly link the ionizing stellar populations with the baryon+metal feedback cycle and the conditions of ionizing photon production and escape. My studies provide a detailed foundation of the diversity of local star-forming galaxies with which to interpret cosmic evolution, as well as unique laboratories of nearly pristine gas in which to test conditions analogous to the first galaxies. In preparation for the coming UV window onto the early universe with the advent of the James Webb Space Telescope and the Giant Magellan Telescope, I will introduce the COS Legacy Archival Spectroscopic SurveY (CLASSY) - an upcoming large HST program that will produce the first high-resolution UV spectral atlas of star-forming galaxies. CLASSY will calibrate new tools that will allow us to completely describe the stars and interstellar medium in galaxies across redshift, setting the stage to study cosmic origins, ionizing production, and the evolution of galaxies in a unified framework.

Jan 15

Special A&A Colloquium: Anna McLeod (University of California, Berkeley)

12:00–1:00 pm ERC 576

Feedback from massive stars, integral field spectroscopy, and serendipitous discoveries

Feedback from massive stars plays a central role in shaping the evolution of entire galaxies. Despite a solid qualitative understanding of feedback, our quantitative knowledge remains poor. Currently, only a small number of HII regions have adequate observational information on both gas and stars needed for detailed feedback studies. However, the growing availability of integral field unit (IFU) instruments and the novel analysis techniques we’ve developed for them, now allow the study of stellar feedback in orders-of-magnitude more HII regions than previously possible, i.e. the numbers needed to fully quantify the effects of feedback over a large dynamic range of stellar and interstellar medium properties, and to connect the results to state-of-the-art star formation and galaxy evolution models.

I will discuss the first results of resolved stellar feedback studies from a MUSE IFU legacy dataset covering the nearby Sculptor galaxy NGC 300, as well as results from MUSE observations of HII regions in the Magellanic Clouds and the Milky Way. By merging the MUSE NGC 300 data with HST resolved stellar photometry, I demonstrate that ground-based IFU data of nearby galaxies is ideally suited to quantify feedback from massive stars all the way down to individual cloud scales. Moreover, I will discuss the MUSE observations in terms of a pathfinder to ongoing and next-generation IFU nearby galaxy surveys and instruments such as the Local Volume Mapper and JWST. Finally, I will highlight serendipitous discoveries only possible thanks to the 3D nature of IFU data.

Jan 14

KICP seminar: Nicholas Orlofsky (University of Wisconsin-Madison)

12:00–1:00 pm ERC 401

“New mass windows and detection prospects for primordial black hole dark matter”

Jan 10

Physics colloquium: Angela Olinto (UChicago)

3:30–4:30 pm KPTC 106

“Space Observatories of the Highest Energy Particles: POEMMA & EUSO-SPB”

Jan 9

Special A&A Colloquium: Austin Joyce (Columbia University)

3:30–4:30 pm ERC 161

From Large to Small: Symmetries and the Origins of Structure in the Universe

What was the universe like in its first moments? Remarkably, we can gain insight into the infancy of universe by looking at the largest scales today, using subtle correlations imprinted at very early times. This striking connection between the very large the very small is an opportunity to use cosmological observations to probe high energies, and also to bring modern theoretical tools to bear on the deep questions that cosmology presents us with. I will discuss recent progress in both directions, highlighting the power of effective field theory and symmetries as guiding principles. As an example, I will explain how the symmetry-oriented viewpoint can help unravel the origins of structure in the universe by enabling us to derive powerful model-independent tests of the simplest inflationary paradigm. Violations of these relations can signal the presence of new heavy particles, allowing us to use the primordial universe as the highest-energy particle accelerator. I will also describe recent theoretical advances in understanding the signatures of these heavy particles, and will explain how these advances could help shed light on fundamental questions, like the emergence of time in cosmology.

Jan 8
Jan 6

2019

Dec 14

Fall 2019 Postdocs Symposium

12:00–6:00 pm ERC 401

Speakers: Nikita Blinov, Victor Buza, Danielle Norcini, Christine Simpson, Yu-Dai Tsai, Kimmy Wu, Yiming Zhong.
Organizers: Daniel Baxter, Anne Gambrel.

Dec 13

Milky Way Discussion Group

2:00–3:00 pm ERC 419

Dec 10

Physics with a Bang!

11:00 am–2:00 pm KPTC

Join us in the Kersten Physics Teaching Center on Dec 7 at 11 AM & 2 PM for fun and exiting physics demos for all ages!

Dec 7