2020
KICP seminar: Carmen Carmona Benitez (Pennsylvania State University)
12:00–1:00 pm ERC 401
“Near Future of Dark Matter Searches: Go Big, or Go Low”
KICP Colloquium: James Bock (California Institute of Technology)
3:30–4:30 pm ERC 161
“SPHEREx: An All-sky Infrared Spectral Survey Explorer Satellite”
Chalk Talk: Congyao Zhang (UChicago) & Francisco Javier Sanchez Lopez (Fermilab)
12:00–1:00 pm ERC 501
Congyao Zhang (UChicago)
“Formation of Galaxy Clusters – from the Core to the Outskirts”
&
Francisco Javier Sanchez Lopez (Fermilab)
“Olber’s paradox revisited: effects of overlapping sources on cosmic shear estimation”
KICP seminar: Tien-Tien Yu (University of Oregon)
12:00–1:00 pm ERC 401
“A New Look at the Migdal Effect”
College Break
All day
A&A Colloquium - Lorenzo Sironi (Columbia)
3:30–4:30 pm ERC 161
Fast and furious: magnetic reconnection in relativistic jets and black hole coronae
Relativistic jets of blazars and magnetized coronae of low-luminosity accretion flows, like Sgr A* at our Galactic Center, routinely display fast and bright flares of high-energy emission. Yet, the “engine” responsible for accelerating the emitting particles to ultra-relativistic energies is still unknown. With fully-kinetic particle-in-cell (PIC) simulations, we argue that magnetic reconnection — a process by which magnetic field lines of opposite polarity annihilate, releasing their energy to the particles — can satisfy all the basic conditions for the emission. In blazar jets, we show that reconnection can naturally explain the puzzling ultra-fast bright flares observed at GeV and TeV energies, whose duration can be even shorter than the light-travel time across the black hole that powers the jet. In low-luminosity accretion flows like Sgr A*, we show that reconnection — potentially seeded by turbulence — can power both thermal and non-thermal emission, and we produce physically-grounded synthetic images and spectra to be compared with infrared and X-ray observations and with the upcoming results of the Event Horizon Telescope.
Special A&A Colloquium: Benjamin Fulton (Caltech)
12:00–1:00 pm ERC 576
Is our Solar System Unique? A Holistic View of Exoplanet Demographics
The Kepler and K2 missions blessed the community with a plethora of planet transit detections which enabled studies of exoplanet size demographics. Much of the recent progress in this field is driven by improved characterization of the stellar hosts. Our group recently used precise radius measurements from the California-Kepler Survey (CKS) to detect a gap in the distribution of planet radii. The paucity of planets with sizes between 1.5 and 2.0 Earth radii supports the emerging picture that close-in planets smaller than Neptune are composed of small, rocky cores enveloped by varying amounts of low-density gas that determine their total sizes. This result demonstrated the value of precise and homogeneous stellar parameters. I will discuss implications of the radius distribution and our ongoing and complimentary work to measure the frequency of giant planets orbiting well beyond the snow line. The occurrence of close-in planets from Kepler combined with the latest results from long-baseline radial velocity surveys allow us to construct a comprehensive picture of planetary system architectures spanning three orders of magnitude in orbital separation and planet mass.
KICP seminar: Jessica M Turner (Fermilab)
12:00–1:00 pm ERC 401
“Heavy neutrinos and their role in the early Universe”
KICP colloquium: Abigail Crites (University of Toronto)
3:30–4:30 pm ERC 161
“Measuring the Epoch of Reionization with Line Intensity Mapping using TIME”