Workshops & Events
Daniel Holz, UChicago, "GW170817: Hearing and Seeing a Binary Neutron Star Merger"
February 1, 2018 | KPTC 106 | 4:00 PM | Event
Artist's impression of the collision of two neutron stars, the source of the latest gravitational waves detected.
Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet
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With the discovery of GW170817 in gravitational waves, and the discovery of an associated short gamma-ray burst, and the discovery of an associated optical afterglow, we have finally entered the era of gravitational-wave multi-messenger astronomy. I will discuss LIGO/Vigo's detection of this binary coalescence, and explore some of the scientific implications, including confirmation of the kilonova model and implications for the origin of gold and platinum in the universe, tests of general relativity, and the first standard siren measurement of the Hubble constant. GW170817 represents a momentous development in gravitational-wave astronomy, and the birth of gravitational-wave cosmology.

Winter 2018 Postdocs Symposium
February 23, 2018 | ERC 401 | 1:00 PM | Event
1:00 PM
2:00 PM
Lightning talks
3:40 - 4:00 PM
4:00 PM
5:00 PM
Dinner and networking/socializing

GeoSci Seminar: Vikram Dwarkadas, "Investigating a Stellar Wind Origin for High 26Al and Low 60Fe in the Early Solar System"
March 1, 2018 | Hinds 176 | 12:30 PM | Event
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A critical constraint on solar system formation is the high 26Al/27Al abundance ratio of 5e-5 at the time of formation, which was about 17 times higher than the average Galactic ratio, while the 60Fe/56Fe value was about 2e-8, lower than the Galactic value of 3e-7. This challenges the assumption that a nearby supernova was responsible for the injection of these short-lived radionuclides into the early solar system. We show that this conundrum can be resolved if the Solar System was formed by triggered star formation at the edge of a Wolf-Rayet (W-R) bubble. Aluminium-26 is produced during the evolution of the massive star, released in the wind during the W-R phase, and condenses into dust grains that are seen around W-R stars. The dust grains survive passage through the reverse shock and the low density shocked wind, reach the dense shell swept-up by the bubble, detach from the decelerated wind and are injected into the shell. Some portions of this shell subsequently collapses to form the dense cores that give rise to solar-type systems. The subsequent aspherical supernova does not inject appreciable amounts of 60Fe into the proto-solar-system, thus accounting for the observed low abundance of 60Fe. We discuss the details of various processes within the model using numerical simulations, as well as nucleosynthesis modelling, and analytic and semi-analytic calculations. We conclude that it is a viable model that can explain the initial abundances of 26Al and 60Fe.

Astronomy & Astrophysics Open House
March 2, 2018 | ERC 5th floor | 9:00 AM | Event
9:00 - 10:30 am
Welcome and Presentation
Speakers: Profs. Fausto Cattaneo, John Carlstrom, Brad Benson, Dan Fabrycky, Damiano Caprioli, Rich Kron
ERC 545
10:30 - 12:00 pm
12:00 - 1:15 pm
Student Panel Discussion w/lunch
ERC 545
1:30 - 3:00 pm
3:00 - 3:30 pm
Outreach Presentation - Maria Weber
ERC 545
3:30 - 4:00 pm
Graduate Program Talk - Julia Brazas and Laticia Rebeles
ERC 545
4:00 - 4:30 pm
Diversity and Inclusion Talk - Mike Gladders, Nora Shipp, Gourav Khullar
ERC 545
4:30 - 6:00 pm
Wine and Cheese Reception
ERC 5th Floor Lounge

EFI seminar: Nahee Park, University of Wisconsin, "Probing high energy particle dynamics in our Galaxy with multimessenger observations"
March 14, 2018 | PRC 201 | 2:00 PM | Event
Cosmic rays, high energy particles originating from outside of the solar system, are believed to be dominated by particles from our Galaxy at least up to the energy of 10^15 eV. Since their discovery in 1912, the origin, acceleration, and propagation of these high energy particles have remained as open questions. In the last few years, new results from space-borne experiments, such as the rise of the positron flux and hardening of the light nuclei, have begun to challenge our understanding of these particles. Complementing this, indirect observations of the cosmic rays via very high energy gamma rays have started to shed light on the various particle accelerators in our Galaxy with discoveries of over a hundred Galactic sources. With the recent detection of astrophysical neutrinos by IceCube, the first unequivocal view of pure hadronic accelerators in our Universe became available. I will present what we have learned about the acceleration of high energy particles with gamma-ray observations based on the Galactic gamma-ray measurements from the VERITAS experiment, an imaging atmospheric Cherenkov telescope. I will show what we can learn from the future neutrino experiment IceCube Gen-2 and the future gamma-ray observatory CTA. Finally, I will highlight how these multimessenger observations come together to lead us toward a more coherent and complete picture of high energy particles in our Galaxy.

Workshop: Towards Dark Matter Discovery
April 11 - 13, 2018 | Chicago, IL | Event
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The Kavli Institute of Cosmological Physics (KICP) at the University of Chicago is hosting the "Towards Dark Matter Discovery" workshop, which will be held from 11th to 13th April 2018 in the Eckhardt Research Center (ERC) on the University of Chicago campus.

The workshop will explore new directions on the path toward discovering the nature of dark matter. The invited speakers are encouraged to share their expertise in the fields of primordial black holes, thermal relic dark matter, nonthermal relic dark matter, ultralight dark matter, superheavy dark matter, kinda-chubby dark matter, new strategies for direct detection, newer strategies for direct detection, avant-garde strategies for direct detection, and axions. During the three day workshop, we will host approximately 20 talks of 30 minutes each with generous time remaining for discussion.

Visitors to the University of Chicago are invited to spend the entire week at the university.

Workshop: Near-Field Cosmology with the Dark Energy Survey's DR1 and Beyond
June 27 - 29, 2018 | Chicago, IL | Event
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Stars in our Milky Way and galaxies in our Local Group contain the fossils and clues on stellar evolution and supernovae, the formation and evolution of star clusters and dwarf galaxies, and the formation of large spiral galaxies. Rapid progress in this field -- usually called Galactic Archeology -- was enabled by large-area imaging and spectroscopic surveys of old stellar components of the Milky Way and dwarf galaxies, together with simulations of chemical and dynamical evolution. The field of Near-Field Cosmology extends the scope of these studies to probe the formation and evolution of galaxies and the nature of dark matter.

The Dark Energy Survey (DES) is releasing its DR1, with catalogs and images from the first three years of DES operations early in 2018, including 400M objects (100M stellar sources in grizY band to r of 24th magnitude at 10 sigma) over 5000 square degrees mostly in the Southern Galactic cap. This survey is about 2 magnitudes fainter than SDSS at the same S/N. In addition to DES, many other DECam community surveys, such as DECaLS, DECaPS, SMASH, MagLiteS, BLISS, etc, have already had or will soon have the public data release.

Kavli Institute for Cosmological Physics (KICP) at the University of Chicago will host a 3-day workshop on June 27-29 to explore uses of the DES DR1 for near field cosmology studies in conjunction with other DECam public data. Furthermore, the workshop will explore possible synergies with other spectroscopic surveys as well as Gaia DR2.

The 3-day workshop will include presentations and discussion on the first two days and a hack day on the last day. Talks on ideas or science results related to DES/DECam data, or synergies with other programs are encouraged. Abstracts can be submitted at registration. On the hack day, we will hack on DES DR1 data and associated data sets (like Gaia DR2) in a collaborative format. Specific hack topics can be submitted at registration.

Topics in this workshop includes:
  • Dark Matter and Near-Field Cosmology
  • Milky Way satellite galaxies - satellites of satellites, planes of satellites, dark matter particle physics
  • Stellar streams and halo overdensities -- constraints on Milky Way dark matter halo
  • First stars; Reionization; Chemical Evolution -- r-process variation
  • Time series photometry and RR Lyrae stars -- distant structure tracers
  • Local Group and Nearby Galaxies -- Ultra-Diffuse Galaxies
  • Synergy with Gaia DR2 and other spectroscopic programs/surveys.
  • Synergy with other DECam surveys and/or other imaging surveys.