KICP Seminars & Colloquia
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KICP Seminars & Colloquia, Current and Future
Today's Seminar
Upcoming Seminars
Seminar schedule for Current (Spring 2019) & Future Quarters
April 3, 2019
Astronomy Colloquium | Sean Raymond
Laboratoire d'Astrophysique de Bordeaux, France | Why doesn't the Solar System have close-in super-Earths? [Abstract] |
April 5, 2019
Friday noon seminar | Maximiliano Isi
MIT | Testing general relativity with LIGO and Virgo [Abstract] |
April 10, 2019
Astronomy Colloquium | Sara Seager
MIT | The Search for Biosignature Gases on Exoplanets [Abstract] |
April 12, 2019
Friday noon seminar | Katerina Chatziioannou
Flatiron Institute | What can we learn about extreme matter from colliding neutron stars [Abstract] |
April 12, 2019
Open Group seminar | Douglas Scott
UBC | Is the Universe lop-sided? [Abstract] |
April 17, 2019
Wednesday colloquium | Lars Bergstrom
The Oskar Klein Center, Physics Dept., Stockholm University | WIMP Dark Matter - dead or alive? [Abstract | Video] |
April 19, 2019
Friday noon seminar | Rebecca K Leane
MIT | Dark Matter Strikes Back at the Galactic Center [Abstract] |
April 23, 2019
Astronomy Tuesday Seminar | Noemie Globus
NYU-CCA | The origin of the ultra-high energy cosmic-ray dipole [Abstract] |
April 24, 2019
Wednesday colloquium | Jeff McMahon
University of Michigan | Advancing CMB Cosmology: ACTPol and onward to CMB-S4 [Abstract | Video] |
April 25, 2019
Open Group seminar | Nicole Larsen
AAAS/US Department of Defense | Roads to Washington: Moving into Policy as a STEM PhD |
April 26, 2019
Friday noon seminar | Junhan Kim
University of Arizona | First Event Horizon Telescope Results: M87 [Abstract] |
May 1, 2019
Open Group seminar | Luca Visinelli
Uppsala University, Sweden | Probing the Early Universe with Axion Physics [Abstract] |
May 1, 2019
Astronomy Colloquium | Dara Norman
National Optical Astronomy Observatory (NOAO) | Can Big Data Lead an Inclusion Revolution? [Abstract] |
May 3, 2019
Friday noon seminar | Garrett K Keating
Harvard-Smithsonian Center for Astrophysics | Charting the Molecular Gas of the Universe Across Cosmic Time [Abstract] |
May 8, 2019
Wednesday colloquium | Patrick J McCarthy
GMTO | Progress with the Giant Magellan Telescope [Abstract | Video] |
May 10, 2019
Friday noon seminar | Michelle Ntampaka
Harvard University | A Deep Learning Approach to Galaxy Cluster X-ray Masses [Abstract] |
May 14, 2019
Astronomy Tuesday Seminar | Robert Kennicutt
University of Arizona and Texas A&M University | Astro2020 Decadal Survey Update and Discussion |
May 15, 2019
Astronomy Colloquium | Rob Kennicutt
University of Arizona and Texas A&M University | The Schmidt Law at Sixty [Abstract] |
May 17, 2019
Friday noon seminar | Kent Yagi
University of Virginia | Gravitational-wave Tests of General Relativity: Present and Future [Abstract] |
May 21, 2019
Astronomy Tuesday Seminar | Kyle Parfrey
NASA Goddard | Black-Hole Energy Extraction via General-Relativistic Kinetic Plasma Simulations [Abstract] |
May 22, 2019
Wednesday colloquium | Justin Vandenbroucke
University of Wisconsin | The multi-messenger astrophysics revolution enabled by neutrinos, gravitational waves, and gamma rays [Abstract] |
May 24, 2019
Friday noon seminar | Caroline D Huang
Johns Hopkins University | The Mira Distance Ladder [Abstract] |
May 28, 2019
Astronomy Tuesday Seminar | Dimitri Veras
University of Warwick | Transformative advances in post-main-sequence planetary system science [Abstract] |
May 29, 2019
Astronomy Colloquium | Ian Crossfield
MIT | Infrared Spectroscopy of Stars and Planets [Abstract] |
June 5, 2019
Wednesday colloquium | Brian Nord
The University of Chicago | TBA [Abstract] |
June 14, 2019
Friday noon seminar | Martina Gerbino
Argonne National Laboratory | Cosmological pathway to neutrino properties |
COLLOQUIA
- April 3, 2019 | 3:30 PM | ERC 401 | Astronomy Colloquium
Why doesn't the Solar System have close-in super-Earths?
Sean Raymond, Laboratoire d'Astrophysique de Bordeaux, France
Jupiter is the only planet in our system that would be detectable if the Sun were observed from afar with current instruments. Its wide, near-circular orbit makes it a ~10% rarity among known giant exoplanets and the Solar System a ~1% rarity among Sun-like stars. Another oddity of the Solar System is the absence of close-in super-Earths, which are found around a significant fraction (~50%) of main sequence stars. Models for the origin of close-in super-Earths can match the distributions of observed systems, although the compositions of super-Earths (icy vs rocky) are a key constraint. However, models are generally too efficient, and cannot explain systems like ours without super-Earths. Jupiter's growth may provide an answer. If Jupiter's core formed quickly, it would have blocked the flux of small `pebbles' drifting inward through the disk and starved the terrestrial planets' building blocks. Once Jupiter was fully-grown it opened a gap in the Sun's protoplanetary disk and may have blocked the inward migration of larger cores, protecting the inner Solar System from icy invaders than instead formed the ice giants and Saturn's core. These ideas remain incomplete but have the promise to explain how the Solar System fits in the larger context.
- April 10, 2019 | 3:30 PM | ERC 161 | Astronomy Colloquium
The Search for Biosignature Gases on Exoplanets
Sara Seager, MIT
Thousands of exoplanets are known to orbit nearby stars and small rocky planets are established to be common. The ambitious goal of identifying a habitable or inhabited world is within reach. But how likely are we to succeed? We need to first discover a pool of planets in their host star's "extended" habitable zone and second observe their atmospheres in detail to identify the presence of water vapor, a requirement for all life as we know it. Life must not only exist on one of those planets, but the life must produce "biosignature gases" that are spectroscopically active, and we need to be able to sort through a growing list of false-positive scenarios with what is likely to be limited data. The race to find habitable exoplanets has accelerated with the realization that "big Earths" transiting small stars can be both discovered and characterized with current technology, such that the James Webb Space Telescope has a chance to be the first to provide evidence of biosignature gases. Transiting exoplanets require a fortuitous alignment and the fast-track approach is therefore only the first step in a long journey. The next step is sophisticated starlight suppression techniques for large ground-and space-based based telescopes to observe small exoplanets directly. These ideas will lead us down a path to where future generations will implement very large space-based telescopes to search thousands of all types of stars for hundreds of Earths to find signs of life amidst a yet unknown range of planetary environments. What will it take to identify such habitable worlds with the observations and theoretical tools available to us?
- April 17, 2019 | 3:30 PM | ERC 161 | Wednesday colloquium
WIMP Dark Matter - dead or alive?
Lars Bergstrom, The Oskar Klein Center, Physics Dept., Stockholm University
Video
The hunt for the identity of dark matter continues with undiminished strength, even though the most popular candidate during recent decades, the Weakly Interacting Massive Particle (WIMP), is facing pressure from non-observation in present-day experiments. In this talk, a review of the situation, discussing some of the WIMP and non-WIMP possibilities, will be given and of some intriguing indications of signals be discussed that may in fact point to the survival of WIMP dark matter. Upcoming experiments may clarify in the next few years whether the dark matter problem thus has been solved, or if a change of paradigm is needed.
- April 24, 2019 | 3:30 PM | ERC 161 | Wednesday colloquium
Advancing CMB Cosmology: ACTPol and onward to CMB-S4
Jeff McMahon, University of Michigan
Video
Measurements of the cosmic microwave background (CMB) are a powerful probe of the origin, contents, and evolution of our Universe. CMB measurements continue to improve according to a Moore's law under which the mapping speed of experiments improves by an order of magnitude roughly every five years. This rapid progression in our ability to measure the CMB has translated into a series of scientific advances including showing our universe to be spatially flat, constraining inflationary and alternative theories of the primordial universe, and providing a cornerstone for our precision knowledge of the Lambda-CDM model. Observations with the current generation of experiments, including Advanced ACTPol, will soon produce improved cosmological constraints. Building on this work, in the coming decade CMB-S4 will: pass critical thresholds in constraints on inflation and light relativistic species; provide improved measurements of dark energy, dark matter, neutrino masses, and a variety of astrophysical phenomena; and enable searches for new surprises. In this talk I present the design and status of measurements with Advanced ACTPol and how we are building on this work to realize the next generations of experiments including Simons Observatory and ultimately CMB-S4. I will highlight the technological advances that underlie the rapid progress in measurements including: polarization sensitive detectors which simultaneously observe in multiple colors; metamaterial antireflection coated lenses and polarization modulators; and overall advances in experimental design. I will present preliminary new results from ACTPol and conclude with science forecasts for CMB-S4.
- May 1, 2019 | 3:30 PM | ERC 161 | Astronomy Colloquium
Can Big Data Lead an Inclusion Revolution?
Dara Norman, National Optical Astronomy Observatory (NOAO)
Ground-based astronomy research is evolving into an era of large surveys and big datasets. With the help of federal funding, many of these datasets are already accessible through public archives and databases. The Large Synoptic Survey Telescope, expected to begin Science Verification in 2021, will be the flagship ground-based facility into the next decade, surveying the accessible sky and delivering 200 petabytes of data over ten years. The survey is an opportunity for a research 'inclusion revolution' by providing data and data products for use by all members of the community. However, this revolution can only be realized if 1) data products are not just accessible, but discoverable and easily useable, and 2) if the broad community of astronomers is prepared to use tools and services to take advantage of these datasets for achieving science goals. At NOAO we are actively engaged in several programs to support broad community use of current data holdings and near-term public surveys as we prepare for the big data sets that will flow once the LSST survey begins. In this talk, I will describe these efforts and the challenges of leading an inclusion revolution.
- May 8, 2019 | 3:30 PM | ERC 161 | Wednesday colloquium
Progress with the Giant Magellan Telescope
Patrick J McCarthy, GMTO
Video
The Giant Magellan Telescope is in the construction phase in north-central Chile. I will provide an update on the status of the project and its potential in fields from exoplanets to first-light in the universe. I will also discuss community wide efforts to develop a case for federal participation in the project.
- May 15, 2019 | 3:30 PM | ERC 161 | Astronomy Colloquium
The Schmidt Law at Sixty
Rob Kennicutt, University of Arizona and Texas A&M University
Sixty years have passed since Maarten Schmidt's conjecture that star formation in galaxies was closely coupled to gas density, and since that time the Schmidt law has become an indispensable tool for interpreting, modeling, and simulating large-scale star formation in galaxies. Despite its success as a sub-grid "recipe" for the star formation rate, however, we remain far away from an ab initio theory of star formation, or even a clear understanding of the observed scaling laws themselves. This talk will review the current state of our observational understanding of star formation in galaxies, and the complexity which lies beneath the surface of the observed SFR scaling relations. We are witnessing an observational and theoretical renaissance in the subject, as multi-wavelength observations reveal the multi-scale nature of the star formation process and the complex interactions which are taking place between cosmological, gravitational, interstellar, and stellar feedback processes on these different scales. The picture which emerges is one in which the superficially simple star formation scaling laws are manifestations of a highly dynamic, complex, and self-regulating ecosystem in galactic disks.
- May 22, 2019 | 3:30 PM | ERC 161 | Wednesday colloquium
The multi-messenger astrophysics revolution enabled by neutrinos, gravitational waves, and gamma rays
Justin Vandenbroucke, University of Wisconsin
In the past few years, the idea of studying high-energy astrophysics with cosmic messengers beyond those of the electromagnetic spectrum has become a reality. The IceCube Neutrino Observatory has discovered and characterized a flux of high-energy astrophysical neutrinos, and LIGO/Virgo have directly detected gravitational waves. Multiple messengers have been used to study individual astrophysical sources including a binary neutron star merger and an energetic blazar. Within the electromagnetic spectrum, high-energy and very-high-energy gamma rays provide an essential link to the newer messengers. I will give my personal view of this quickly developing field, focusing on time domain astronomy with IceCube and the recently inaugurated prototype Schwarzschild Couder Telescope, a TeV gamma-ray instrument demonstrating innovative technology as a pathfinder for the Cherenkov Telescope Array.
- May 29, 2019 | 3:30 PM | ERC 161 | Astronomy Colloquium
Infrared Spectroscopy of Stars and Planets
Ian Crossfield, MIT
Note: Refreshments served at 4:45 PM, Hubble Lounge
Extrasolar planets and cool stars emit most of their light beyond the range of standard optical observations. These objects are often best studied using infrared spectroscopy. I will present recent results from my group on two topics: space-based IR spectroscopy of exoplanet atmospheres, and ground-based, high-resolution spectroscopy of both planets and stars. I will also conclude with a brief discussing of how future IR-optimized observatories will also enable exciting new science in these areas.
- June 5, 2019 | 3:30 PM | ERC 161 | Wednesday colloquium
TBA
Brian Nord, The University of Chicago
TBA
FRIDAY NOON SEMINARS
- April 5, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
Testing general relativity with LIGO and Virgo
Maximiliano Isi, MIT
Gravity remains the least understood of the four fundamental forces. To address this, we would like to experimentally study the extreme phenomena in which the full nonlinear and dynamic richness of gravity comes into play. Gravitational waves are a unique tool to do just that: they carry uncorrupted information directly from strong-gravity objects (like black holes, or their mimickers), and reflect in their own basic properties (like polarization or speed) the fundamental structure of space and time. Thus, gravitational waves are an invaluable resource to experimentally test our best theory of gravity, Einstein's general relativity, in yet unexplored regimes. The ever-increasing number of signals detected by LIGO and Virgo has already allowed us to make progress in this direction. This includes precisely probing the strong-field orbital dynamics of compact-binary mergers, testing the nature of the resulting remnant object, limiting the mass of the graviton and constraining the speed and polarization of gravitational waves. In this talk, I will review the results obtained from the 11 existing confident detections (ten binary black holes and one binary neutron star merger) and explain their relevance in our effort to better understand gravity. I will then discuss the potential for these studies in the near future, as existing detectors reach their design sensitivities, and beyond.
- April 12, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
What can we learn about extreme matter from colliding neutron stars
Katerina Chatziioannou, Flatiron Institute
Image credit: LIGO/Virgo/CoRe
The first detection of the merger of two neutron stars offered, among a plethora of other things, the first constraints on the properties of extremely dense and cold matter with gravitational waves. In this talk I will outline how gravitational waves can be used to probe matter in conditions unattainable in human laboratories. I will describe how the data from neutron star merger GW170817 has been used to infer the radius of the merging bodies and the properties of the equation of state of supranuclear matter. I will further discuss future prospects for equation of state constrains from improved gravitational wave detectors, as well as the post-merger part of the gravitational wave signal. Finally, I will discuss how these systems can be used to gain novel insights about nuclear as well as fundamental physics.
- April 19, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
Dark Matter Strikes Back at the Galactic Center
Rebecca K Leane, MIT
Statistical evidence has previously suggested that the Galactic Center GeV Excess (GCE) originates largely from point sources, and not from annihilating dark matter. In this talk, I will examine the impact of unmodeled source populations on identifying the true origin of the GCE, using non-Poissonian template fitting (NPTF) methods. In a proof-of-principle example with simulated data, I will show that unmodeled sources in the Fermi Bubbles lead to a dark matter signal being misattributed to point sources by the NPTF. I will reveal striking behavior consistent with such an effect in the real Fermi data, finding that an artificial injected dark matter signal is completely misattributed to point sources. I will conclude that dark matter may provide a dominant contribution to the GCE.
- April 26, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
First Event Horizon Telescope Results: M87
Junhan Kim, University of Arizona
The Event Horizon Telescope (EHT) project is a very-long-baseline interferometry experiment to observe supermassive black holes at the highest resolution ever achieved, combining a network of radio telescopes around the world. Recently, the EHT announced its first results: imaging the nuclear black hole in the galaxy M87. The image reconstruction, and a geometric model fit directly to the interferometric data, reveal a bright emission ring around a central intensity depression, consistent with the expected shape for emission from around a Kerr black hole. In this talk, I will review the EHT results, including the instrument development and data processing that led to the first scientific outcome of the project.
- May 3, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
Charting the Molecular Gas of the Universe Across Cosmic Time
Garrett K Keating, Harvard-Smithsonian Center for Astrophysics
In the early Universe, galaxies boasted large reservoirs of gas that fueled a cosmic bonfire of star formation, at rates an order of magnitude greater than that observed locally. But exploring the properties of molecular gas from this era is exceptionally difficult; even sensitive instruments like ALMA and VLA have only made dozens of detections, generally only probing the most massive and luminous of systems. Understanding the molecular gas of this early era calls for a survey that can probe thousands or millions of such galaxies: a difficult goal if targeting individual objects, but may achieved by measuring aggregate emission from many objects, through a power spectrum technique known as "CO intensity mapping." In this talk, I will discuss two intensity mapping experiments: the CO Power Spectrum Survey (COPSS); which resulted in a tentative detection of bulk molecular gas at z~3, and the Millimeter-wave Intensity Mapping Experiment (mmIME), an on-going experiment leveraging the combined power of SMA, ALMA, and VLA to survey molecular gas emission from about a billion years after the big bang to the present day (0.2 < z < 6). With these surveys, we hope to build a better understanding of how the natal star-forming molecular gas of the early Universe transforms from pristine material into the dusty, smoggy clouds found in modern galaxies like the Milky Way; a critical piece in understanding how galaxies have evolved into their present-day state.
- May 10, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
A Deep Learning Approach to Galaxy Cluster X-ray Masses
Michelle Ntampaka, Harvard University
I will present a machine-learning approach for estimating galaxy cluster masses from Chandra x-ray mock observations. I will describe how a Convolutional Neural Network (CNN) -- a deep machine learning tool commonly used in image recognition tasks -- can be used to infer cluster masses from these images, reducing scatter in the mass estimates by up to 50%. I will also show an interpretation tool, inspired by Google DeepDream, that can be used to gain some physical insight into what the CNN sees.
- May 17, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
Gravitational-wave Tests of General Relativity: Present and Future
Kent Yagi, University of Virginia
Compact binary merger events recently discovered by the LIGO and Virgo Collaboration offer us excellent testbeds for probing fundamental physics. In this talk, I will first review the current status of testing extreme (strong and dynamical-field) gravity with gravitational waves from binary black hole and binary neutron star mergers that was previously inaccessible. In particular, I will explain how well one can probe various fundamental pillars in General Relativity. I will next review how these tests will improve in future and what kinds of new tests are possible once space-borne interferometers, such as LISA, are in operation. In particular, I will discuss the possibility of using multi-band gravitational-wave observations by combining space-borne and ground-based detections to further improve the power of probing extreme gravity with gravitational waves.
- May 24, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
The Mira Distance Ladder
Caroline D Huang, Johns Hopkins University
The improved precision in local Hubble constant measurements has revealed a 4.4-sigma discrepancy with the value inferred from observations of the cosmic microwave background under the assumption of a Lambda-CDM cosmology. As alternative distance indicators to Cepheids, Oxygen-rich Mira variables can provide an crosscheck of the Cepheid-calibrated extragalactic distance scale. They may also potentially increase the number of SN Ia calibrators and thus the precision of local Hubble constant measurements. I will discuss the results of a year-long, near-infrared Hubble Space Telescope observations of Mira variables in the SN 2005df host galaxy NGC 1559, the first of four SN Ia host galaxies in which we will search for Mira variables.
- June 14, 2019 | 12:00 PM | ERC 401 | Friday noon seminar
Cosmological pathway to neutrino properties
Martina Gerbino, Argonne National Laboratory
OPEN GROUP SEMINARS
- April 12, 2019 | 2:00 PM | ERC 401 | Open Group seminar
Is the Universe lop-sided?
Douglas Scott, UBC
Since the standard cosmological model is such a good fit to the cosmic microwave background anisotropy data, a great deal of attention has focused on any signs of "physics beyond the standard model". For example, there are a number of "anomalies" seen in the CMB at large angular scales. One particular example is that there appears to be more power on one side of the sky compared to the other. How are we meant to assess whether such anomalies are statistically significant, particularly when there's just one sky? If it has a physics explanation then what might that be? And can we find out more about such anomalies using future observations?
- April 25, 2019 | 5:30 PM | ERC 401 | Open Group seminar
Roads to Washington: Moving into Policy as a STEM PhD
Nicole Larsen, AAAS/US Department of Defense
- May 1, 2019 | 1:00 PM | ERC 401 | Open Group seminar
Probing the Early Universe with Axion Physics
Luca Visinelli, Uppsala University, Sweden
Axions and axion-like particles are excellent dark matter candidates, spanning a vast range of mass scales from the milli- and micro-eV for the QCD axion, to 10^-22eV for ultralight axions, to even lighter candidates that make up the "axiverse". In some scenarios, inhomogeneities in the axion density lead to the formation of compact structures known as axion "miniclusters" and axion stars. Topological defects in the early universe might also contribute the energy density of axions and generate primordial gravitational waves that can possibly be detected in future experiments. I will first discuss astrophysical and cosmological constraints on axions at either end of this spectrum, using data from the cosmic microwave background anisotropies and the effects of miniclusters on the gravitational microlensing and on direct detection. I will then assess the formation and the evolution of axion stars in various astrophysical regimes.
THURSDAY LUNCH DISCUSSIONS
ASTRONOMY TUESDAY SEMINARS
- April 23, 2019 | 12:00 PM | ERC 576 | Tuesday Seminar
The origin of the ultra-high energy cosmic-ray dipole
Noemie Globus, NYU-CCA
Although their astrophysical sources remain a mystery, new measurements brought by experiments such as the Pierre Auger Observatory and Telescope Array, have radically improved our knowledge of the ultra-high energy cosmic-rays (UHECRs). I will review the current observational status (spectrum, composition, and arrival directions) and present new results on the interpretation of the first 5 sigma anisotropy in the UHECR sky: a "dipole" for UHECRs with energies above 8 EeV, reported in 2017 by the Pierre Auger Observatory.
- May 14, 2019 | 12:00 PM | ERC Hubble Lounge | Tuesday Seminar
Astro2020 Decadal Survey Update and Discussion
Robert Kennicutt, University of Arizona and Texas A&M University
- May 21, 2019 | 12:00 PM | ERC 576 | Tuesday Seminar
Black-Hole Energy Extraction via General-Relativistic Kinetic Plasma Simulations
Kyle Parfrey, NASA Goddard
Black holes of all masses drive powerful relativistic jets, using magnetic fields dragged in by their accretion flows. The jets' plasma should be so diffuse as to be effectively collisionless, and self-consistently supplied by pair creation near the horizon. I will present the first general-relativistic kinetic plasma simulations of collisionless black-hole magnetospheres, showing the launching of electromagnetic jets by the Blandford-Znajek mechanism. The simulations reveal a population of particles with negative effective energy, which can contribute significantly to black-hole rotational-energy extraction. The kinetic approach will be useful for studying the accretion flows of the primary Event Horizon Telescope targets, M87 and Sgr A*, where the plasma is likewise of low density and collisionless, and for probing black holes' nonthermal X-ray and gamma-ray emission from first principles.
- May 28, 2019 | 12:00 PM | ERC 576 | Tuesday Seminar
Transformative advances in post-main-sequence planetary system science
Dimitri Veras, University of Warwick
Connecting planetary systems at different stages of stellar evolution helps us understand their formation, evolution, and fate, and provides us with exclusive and crucial insights about their dynamics and chemistry. Post-main-sequence white dwarf and giant branch stars host planetary systems which include a variety of observed objects and phenomena, such as planetary debris discs, disintegrating and embedded asteroids, exo-comets, and photospheric metal pollution. Here, I provide a review of both our current knowledge of these systems and models which have been used to explain them. I also highlight the transformative advances expected in upcoming years with the current and next generation of ground-based and space-based initiatives. Looming orders-of-magnitude increases in available data must be accompanied by novel theories and simulations in order to understand the results from this interdisciplinary and expanding research field.
ASTRONOMY SPECIAL SEMINARS
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Overview