synthetic Gaia surveys of Latte simulations

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 Latte simulations, using 3 solar viewpoints per simulation.  Along with these synthetic surveys, we also released full simulation snapshots at z = 0, including all particle data, from 3 Latte simulations. All data is available at , and our release paper is Sanderson et al 2018.

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

We hope that these fully 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 mission.

NASA ATP grant

NASA’s Astrophysics Theory Program (ATP) has awarded me, together with fantastic co-investigators Robyn Sanderson, Sarah Loebman, and Shea Garrison-Kimmel, a grant of $394,000 for Modeling Galactic Archaeology of the Milky Way. Acknowledgements 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 cosmological simulations of Milky Way-like galaxies into synthetic star catalogs and mock surveys of the Milky Way, and make these datasets publically available, to help inform and guide the vast array of surveys of the Milky Way, including the Gaia satellite mission.

JWST Early Release Science program

We now are decidedly in the era of the James Webb Space Telescope (JWST), which announced its first competitive observing allocations for the Cycle 1 Early Release Science Program. The allocation committee has 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 distant galaxies, JWST also promises significant advancements in observations of resolved stellar populations in nearby low-mass (dwarf) 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!

Sarah Loebman joins us as Hubble Fellow

Sarah Loebman joins our Physics Department and my research group as a joint NASA Hubble Fellow and UC Davis Chancellor’s Postdoctoral Fellow. Previously, Sarah was a postdoctoral fellow in the Michigan Society of Fellows at the University of Michigan. I am tremendously excited that Sarah is joining our group, which is now a real ‘group’! Looking forward to a productive collaboration, as Sarah starts to brainstorm project ideas and applications for our Latte simulations of Milky Way-like galaxies.

Aspen summer workshop

The Aspen Center for Physics has accepted our proposal for a summer workshop in 2018 on the Dynamics of the Milky Way System for the Era of Gaia. Thanks to superb co-organizers Sarah Loebman, Robyn Sanderson, Hans-Walter Rix, Nita Kallivayalil, and Juna Kollmeier. Our workshop will occur 2018 Aug 26 – Sep 16, and will focus on observational analysis and theoretical modeling of stellar dynamics of the entire Milky Way system, from stars in the disk and bulge to the satellite dwarf galaxies, stellar streams, and stars throughout the halo, as we enter the era of the incredible Gaia satellite mission. We aim to bring together observers, modelers, and simulators, to discuss (1) how to analyze this wealth of high-precision dynamics data and (2) how to develop accurate, cosmologically informed models to interpret them. The overarching goals are galactic archaeology, to understand the full 3D formation history of the entire Milky Way system, and near-field cosmology, to use stellar dynamics to measure the distribution and test the nature of dark matter. If interested, apply here by 2018 Jan 31.

real job gets real

Having been on leave (and pretending still to be a postdoc) over the last year, today I fully assume my position as Assistant Professor of Physics at UC Davis.

HST Theory grant

Space Telescope Science Institute has awarded me, together with fantastic co-investigators Shea Garrison-Kimmel, Phil Hopkins, Cameron Hummels, Sarah Loebman, and Robyn Sanderson, a Hubble Space Telescope Theory grant of $116,000 for Understanding the physics of gas stripping and star-formation quenching of the satellite dwarf galaxies in the Local Group. Our goal is to use our new Latte simulations to understand how satellite dwarf galaxies evolve after they fall into a host halo like the Milky Way, with emphasis on how (internal) stellar feedback and (external) environmental processes like ram-pressure stripping remove their gas and quench their star formation, as observed in the satellites of the Milky Way.

160 million CPU-hours on Blue Waters

The National Science Foundation (NSF) has awarded our FIRE collaboration an allocation of 160 million core-hours on NCSA’s Blue Waters supercomputer for Probing New Physics in Galaxy Formation at Ultra-High Resolution. With this allocation, we will push our FIRE simulations, include the Latte simulations of Milky Way-like galaxies, to unprecedented resolution: cosmological zoom-in simulations using over a billion particles per galaxy. We also will include new physical processes, including magneto-hydrodynamics, self-consistent cosmic ray transport/feedback, and full radiative transfer. Congratulations to the whole FIRE collaboration!

HST Treasury Program: MW-6D

Space Telescope Science Institute has awarded Nitya Kallivayalil (as PI) and me (as co-PI)—with co-investigators Jay Anderson, Gurtina Besla, Tom Brown, Alis Deason, Tobias Fritz, Marla Geha, Raja Guhathakurta, Evan Kirby, Steve Majewski, Josh Simon, Tony Sohn, Erik Tollerud, and Roeland van der Marel—a Hubble Space Telescope Treasury Program of 164 orbits for Milky Way Cosmology: Laying the Foundation for Full 6-D Dynamical Mapping of the Nearby Universe.

Our HST observations will provide the initial baselines for long-term proper-motion measurements for all of the known satellite dwarf galaxies around the Milky Way. Our goal is to measure the orbital motions of these satellites as they move across the sky over the next 3 – 10 years, to complete their full 6-dimensional orbital phase-space. Our key science goals are to:

(1) Dynamically measure the mass distribution of the Milky Way’s dark-matter halo
(2) Understand the role of the Milky Way’s environment on the evolution of dwarf galaxies
(3) Use dwarf galaxies as probes of the epoch of reionization
(4) Test physical associations of dwarf galaxies
(5) Eventually, measure internal stellar kinematics of dwarf galaxies, to test the nature of Cold Dark Matter (CDM)

As part of this Treasury Program, we also were awarded $726,000 in grant funding, to analyze these observations and develop our framework for dynamical modeling.