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Scialog Fellowship and Heising-Simons grant

The Research Corporation, with support of the Heising-Simons Foundation and the Kavli Foundation, once again has selected me to be a Scialog Fellow. I was delighted again to join 50 fellows at the 2019 Scialog conference on Time Domain Astrophysics in Tuscon, Arizona, during which we discussed exciting applications of data from NASA’s TESS space telescope, ESA’s Gaia space telescope, and the Zwicky Transient Facility.

I am excited that the Heising-Simons Foundation selected the grant that Keith Hawkins, Jennifer van Saders, and I submitted during this meeting: Aging Gracefully: Stellar Ages Across the HR Diagram and Their Implications for Galactic Archaeology. With this seed funding, our goal is two-fold:

  1. Use the Latte FIRE-2 Milky Way-like simulations as a testbed to quantify the observational precision in stellar ages that we require for specific Milky Way studies.
  2. Compile a unified framework for combining/comparing different ways of measuring stellar ages in an easy-to-use Baysian framework.

    I am excited to work with Keith and Jen on this project over the next year!
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Sierra Chapman graduates with Highest Honors

Sierra Chapman

Sierra Chapman, who has been pursuing research with us as part of her Honor’s Thesis, graduates with her bachelor’s degree in physics. Moreover, for her excellent work on her Honors Thesis, in which she predicts the population of low-mass dark-matter subhalos that orbit close to the Milky Way, she earned Highest Honors. Sierra will continue to pursue research with us over the summer. Congratulations Sierra!

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first student-led paper from our group: radial distribution of satellite galaxies

Radial distance distribution of satellite galaxies around MW-mass galaxies in the FIRE-2 simulations, as compared with the MW and M31

We are excited to announce the first student-led paper from our group, from PhD student Jenna Samuel: A profile in FIRE: resolving the radial distributions of satellite dwarf galaxies in the Local Group with simulations. Jenna examined the radial distance distribution of satellite galaxies around MW/M31-mass galaxies in our FIRE simulations, which she showed are consistent with the Local Group and with MW-like galaxies from the SAGA survey. Interestingly, more massive host galaxies have fewer satellites at small distances, because of tidal destruction from the host galaxy. Jenna also quantified the destruction of subhalos by comparing our baryonic simulations to their dark matter-only versions, finding 10x fewer subhalos within the inner 20 kpc. Finally, Jenna applied observational completeness within the LG to our simulations, predicting 2-10 more satellites with stellar mass > 1e5 Msun to be discovered around the MW and 6-9 around M31. Congratulations to Jenna for an excellent first paper!

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Frontera supercomputer allocation: 106 million core-hours

The National Science Foundation (NSF) has awarded our FIRE collaboration an allocation of 106 million core-hours on the Texas Advanced Computing Center‘s new Frontera Supercomputer, which debuted as 5th most powerful supercomputer in the world. With this allocation, we plan to push forward on a range of large simulation projects, including our FIREbox large-volume simulation and a suite of simulations including alternative dark matter models. Congratulations to the FIRE collaboration!

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Ananke: synthetic Gaia surveys

synthetic Gaia DR2-like surveys from the Latte suite of FIRE-2 cosmological simulations of Milky Way-mass galaxies

We are excited to announce the release of our synthetic Gaia DR2-like surveys from our Latte suite of FIRE-2 cosmological simulations of Milky Way-mass galaxies. We generated 9 synthetic surveys from 3 simulations, using 3 solar viewpoints per simulation.  Along with these synthetic surveys, we also released the full simulation snapshots, including all particle data. All data is available at , and the paper that describes our methods is Sanderson et al 2020.

Congratulations to Robyn Sanderson for leading this ambitious effort, including developing our new Ananke framework for generating synthetic surveys from baryonic simulations. Thanks to Kacper Kowalik and Matt Turk for help hosting this data via the awesome .

We hope that these cosmological synthetic Gaia DR2-like surveys will provide useful tools to the scientific community in interpreting the amazing data of the Milky Way from the Gaia space telescope.

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NASA Astrophysics Theory Program (ATP) grant: modeling the Milky Way

NASA’s Astrophysics Theory Program (ATP) has awarded our team

a grant for Modeling Galactic Archaeology of the Milky Way. Kudos in particular to Robyn Sanderson, who led a significant component of our science case. Our primary goal with this grant is to turn our Latte suite of FIRE-2 simulations of Milky Way-like galaxies into synthetic star catalogs and mock surveys of the Milky Way, and make these datasets publically available, to provide theoretical predictions and tools for the many surveys of the Milky Way, including the Gaia space telescope.

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James Webb Space Telescope (JWST) Early Release Science program: resolved stellar populations

JWST

The James Webb Space Telescope (JWST) announced its first competitive observing allocations for the Cycle 1 Early Release Science (ERS) program, and the allocation committee awarded our team, led by Dan Weisz, 27 hours for The Resolved Stellar Populations Early Release Science Program. While much focus of JWST for galaxy science has emphasized high-redshift galaxies, JWST also promises significant advancements in observations of resolved stellar populations in nearby galaxies and star clusters, to understand their star formation histories, stellar initial mass functions, dust extinction, and (combined with HST) proper motions. Congratulations to Dan and the whole team!