Events Archive

What Peculiar Transients Can Teach Us About Stellar Evolution and Stellar Death

Mon, Sep 21, 2015 at 12:00 pm

131A Campbell Hall

Maria Drout (Harvard Cfa)

Multi-wavelength observations of supernovae not only probe the explosion mechanism, but also carry information about the configuration of the star at the moment of collapse and the mass-loss history of the progenitor system in the years immediately preceding its death. The study of supernovae therefore offers us one of our only observational views of the final stages of stellar evolution. As a …

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All Planets Great and Small

Thu, Sep 17, 2015 at 4:00 pm

1 LeConte

Rebekah Dawson, UC Berkeley

Discoveries of exoplanets so different from those in our Solar System have called in question conventional theories for how planetary systems form and evolve. I will present recent progress in our understanding of the physical processes that drive the assembly of planetary systems and result in the surprising variety of orbital architectures we observe today. I will …

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Department Lunch Talk 9-17

Thu, Sep 17, 2015 at 12:30 pm

131A Campbell Hall

Jonathan Zrake (Stanford)
Philipp Moesta (UCB)
Bekki Dawson (UCB - colloq. spkr.)

Jonathan Zrake (Stanford) - "Fast magnetic free energy discharge by turbulence in force-free electrodynamics". Philipp Moesta (UCB) - "MHD-driven Supernovae in Three Dimensions" Bekki  Dawson (UCB - colloq. spkr.) - “The stellar activity problem for exoplanets”

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Paths, Roadblocks, and Byways in Detecting Habitable Rocky Planets in Radial Velocity Data

Wed, Sep 16, 2015 at 3:00 pm

131A Campbell Hall

Sharon Wang (PSU)

The synergy between Kepler and the ground-based radial velocity (RV) surveys have made numerous discoveries of low-mass exoplanets, opening the age of Earth analogs. However, Earth analogs such as Kepler 452-b require a much higher RV precision ( ~ 10 cm/s) than the achievable with current instruments (~ 1 m/s) and understanding of stellar photosphere. I will talk about instrumental and data …

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Theoretical approaches for studying the epoch of reionization and Dark Matter annihilation

Tue, Sep 15, 2015 at 1:00 pm

131A Campbell Hall

Alex Kaurov (Chicago)

We explore the properties of the intergalactic medium (IGM) during the epoch of reionization numerically. Our simulation models fully self-consistently all relevant physics, from radiative transfer to gas dynamics and star formation, in volumes of up to 40 co-moving Mpc, and with spatial resolution approaching 100 pc in physical units. The achieved resolution allows us to consider the IGM to …

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Cooling, AGN Feedback and Star Formation in Simulated Cool-Core Galaxy Clusters

Mon, Sep 14, 2015 at 12:00 pm

131A Campbell Hall

Yuan Li (University of Michigan)

The feedback from active galactic nuclei (AGNs) is widely considered to be the major heating source in cool-core galaxy clusters, preventing a classical cooling flow where the intra-cluster medium (ICM) cools at hundreds to a thousand solar masses per year. Numerical simulations with AGN feedback have successfully suppressed radiative cooling, but generally fail to reproduce the right amount …

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The Assembly of MASSIVE Elliptical Galaxies

Thu, Sep 10, 2015 at 4:00 pm

1 LeConte

Jenny Greene (Princeton)

Elliptical galaxies comprise the most massive galaxies in the universe today, but their assembly history remains a mystery. I study present-day elliptical galaxies in detail, including their surface brightness profiles, steller population gradients, angular momentum profiles, and gas content, to understand the roles or merging, gas accretion, and black hole growth on the …

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Department Lunch Talk 9-10

Thu, Sep 10, 2015 at 12:30 pm

131A Campbell Hall

Lauren Weiss, UCB
Melissa Graham, UCB
Jenny Greene, Princeton & UCB [Miller Professor, colloq. spkr.]

The Department Lunch Talk series is a weekly event that features three 20 minute talks presented mainly by local scientists of any level to present their work to a broad spectrum of the department and usually includes one short talk by the astronomy colloquium speaker of the day.  Subjects can include personal scientific research, reporting on other work appearing in journals, education and public outreach efforts, science policy, and professional development issues.

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Composition and distribution of clouds in hot Jupiters atmospheres

Wed, Sep 9, 2015 at 3:00 pm

131A Campbell Hall

Vivien Parmentier (UCSC)

Over a large range of equilibrium temperatures clouds seem to dominate the transmission spectrum of hot Jupiters atmospheres but no trend allowing the classification of these objects have yet emerged. Recently observations of the light reflected by these planets provided insight on the cloud distribution on the dayside of these planets : for a handful of planets clouds seem more …

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Large-Scale Structure beyond the Power Spectrum

Tue, Sep 8, 2015 at 1:00 pm

131 Campbell Hall

Marcel Schmittfull, UCB

As recent and future galaxy surveys map the large-scale structure of the universe with unprecedented pace and precision, it is worthwhile to consider innovative data analysis methods beyond traditional Gaussian 2-point statistics to extract more cosmological information from those datasets. Such efforts are often plagued by substantially increased complexity of the analysis. Hoping to improve …

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Atmospheres of Extrasolar Planets in the Super-Earth Era

Thu, Sep 3, 2015 at 4:00 pm

2 LeConte Hall

Heather Knutson (Caltech)

Ongoing surveys of nearby stars have revealed an amazing diversity of planetary systems, many of which have characteristics that differ substantially from those of the solar system planets. Perhaps one of the biggest surprises to come out of these surveys was the discovery that "super-Earths" (planets between 1-10 times the mass of the Earth) are one of the most common types of …

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Department Lunch Talk 9-3

Thu, Sep 3, 2015

131A Campbell Hall

James Graham (UCB)
Carl Heiles (UCB)
Heather Knutson (Caltech)

James Graham, UCB - "Recent Results from The Gemini Planet Imager" Carl Heiles, UCB - Can we see coronal mass ejections on stars other than the Sun?? Heather Knutson, CalTech [colloq. spkr.] - "Spitzer Observations of the Massive, Eccentric Transiting Planet HAT-P-2b”

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Friends of Hot Jupiters: Exploring the Dynamical Evolution of Planetary Systems

Wed, Sep 2, 2015 at 3:00 pm

131 Campbell Hall

Heather Knutson (Caltech)

Since the discovery of the first extrasolar planet around a sun-like star nearly two decades ago, exoplanets have revolutionized our understanding of planet formation and migration. Although it was suspected at the time that the giant planets in our own solar system might have undergone some orbital evolution, the discovery of a class of short-period gas giant planets known as …

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Unveiling the Link Between Supermassive Black Holes and Galaxies

Tue, Sep 1, 2015 at 1:00 pm

131A Campbell Hall

Ai-Lei Sun (Princeton)

Feedback from Active galactic nuclei (AGN) has been proposed as an important quenching mechanism to suppress star formation in massive galaxies. We investigate the most direct form of AGN feedback - galactic outflows, in the most luminous AGN in the nearby universe. Using ALMA and Magellan observations to target molecular and ionized outflows, we find that luminous AGN can impact the dynamics …

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Fast and Furious: Young Supernovae and Their Progenitors

Mon, Aug 31, 2015 at 12:00 pm

131 Campbell Hall

Yi Cao (Caltech)

Observations of supernovae within a few days of explosion provide unique constraints to the nature of their progenitors. Since 2013, as a part of my thesis, I used the intermediate Palomar Transient Factory (iPTF) to systematically study extraordinarily young supernovae. I will first provide an overview of iPTF survey design, summarize the fast turnaround …

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