structure of GD-1 2. Improve phase-space models of known stellar streams (e.g., GD-1, Pal 5) 3. Confirm / re-discover some other “known” streams want to learn: How to construct a very specific selection function in the GD-1 footprint will bring: Expertise in Python/Astropy; Gaia data access and use; galactic dynamics and practical tools; stellar streams; Bayesian inference want to discuss: Stellar populations of globular clusters vs. ultra-faint dwarf galaxies; dynamical inference / dark matter; star / globular clusters Adrian Price-Whelan (Princeton)
for membership selection - search for extended structures around star clusters - build dynamical models of star clusters using Gaia+other data(?) Want to learn: - how to find and access other sources of astronomical data besides Gaia Can share: - how to cope with systematics in Gaia astrometry - galaxy modelling framework Agama: potentials, actions, dynamical models... Eugene Vasiliev (Institute of Astronomy, Cambridge)
time series: how far can we go? 2. Any δ Scuti or SX Phoenicis fans to validate the Gaia DR2 candidates? 3. How to best exploit the public time series of unpublished variability classes? What I want to learn: complementary data sets; streams; local dark matter density What I bring: 1. Gaia DR2 variable stars + Classification of high-amplitude pulsators 2. How to access, crossmatch, and get started with the Gaia DR2 data 3. (Semi-)supervised classification and all what is needed to make it work What I would like to discuss: variability phenomena; unsupervised classification; quasars; gravity Lorenzo Rimoldini (University of Geneva, CH)
tails of existing GCs • Dynamical Evolution of GCs in the MW What I bring:: A new clustering method StarGO based on self-organizing-map (unsupervised neural network learning) Applications: Substructures, Star Clusters, Any Clustering Projects Example: Member Identification For NGC 5824 want to learn: • Statistical tools (e.g. non-parametric way to decompose multiple Gaussians) • A variety of ways to download Gaia data • Mock MW from Latte Simulations want to discuss: • Archeological Fossils: Dwarfs & GCs • What can we learn from abundances?
RRLs • RRLs around GCs, RRLs in known streams RRLs in Pal-5 stream (Institute of Astronomy, Cambridge) RRLs around M5 4 Rt Want to do: Want to learn: Ask me about / What I bring: Want to discuss: • Methods to estimate the phase-space density • Clustering methods / Associate stars to known GC/Sats/streams • MW stellar halo • RRLs in Gaia (I bring catalogs of all RRLs classified in Gaia DR2 with additional information) • (non cosmological) N-body simulations (I bring catalogs of an LMC-like destroyed in the MW, credit D. Erkal) • Gaia selection function / completeness • How to find shells in the MW halo • Can we improve distance estimate for RRLs?
the medium/faint end of Gaia astrometry: Tycho, WFPC2? ACS? • Want to learn: how else can we understand Gaia uncertainties and systematics? • What I bring: Cross-calibration of Gaia DR2 to Hipparcos (HGCA), fitting orbits with the HGCA, RV, imaging • Want to discuss: how can we get the best handle on spatially correlated systematics, external uncertainties? P~100-400 years
want to do: a. Exploit ~200 million asteroid positions reduced with pre-Gaia catalogs b. Optimize my brand new approach to correct zonal errors for those catalogs c. Study the results and start writing an article! What I want to learn: write better ADQL queries, launch python parallel threads, and all that you can share about systematics in ancient catalogs. What I bring: Solar System data expertise. Zonal error corrections for ~3000 asteroids, ~20 catalogues. Independent cross-match approach. What I would like to discuss: Spatially correlated errors. Clustering algorithms for multi-dimensional data. Good beers.
as Gaussian process regression to Gaia data to build models for the phase space DF. Want to learn: Better methods for GPR including application of sparse GP to problems in 3-6 dimensions and with observational errors. What I bring: Preliminary success modelling 3D velocity field via GPR. Familiarity with GPy. Have also worked on building equilibrium disk models and embedding them in cosmological halos. What I want to discuss: Theoretical underpinning of phase space structure in stellar DF and other methods to analyse both data and simulations.
to do: What you can ask me about: SQL databases Stellar population synthesis models • Cross-match E-IRTF library with Gaia • Normalize spectra to Gaia photometry • Infer luminosity for each E-IRTF star in manner similar to Hawkins et al. 2017 What I want to learn: How to choose informative priors when using the parallax measurements Use Gaia to turn the E-IRTF stellar spectra library into new SPS models E-IRTF
eclipsing binaries to translate excess astrometric noise to tangential motion, and estimate inclination angles for non-eclipsing binaries What I want to learn >> is the distribution of inclination angles isotropic? What I bring >> Zen. My time (for your Sprint problems). Experience in data analysis, some knowledge about stars What I’d like to discuss >> astrometry >> (other things….) >> thoughts about next Gaia data release
a 3D dust map to real data, profile the python code to minimize compute time, sprint with Juna What I want to learn: data viz with yt (3d rendering and sim reconstruction), limits of GP method with real data, more intuition for how approximate GP methods work What I’d like to chat about: interpreting structures in a 3D dust map, including velocity in the dust map, non-parametric representations of galactic potentials, inference of the MW halo shape/accretion history from stellar streams, structures in the CMD, modeling and interpreting the phase space distribution function of stars What I bring: GP 101 description, data-driven models, curiosity and optimism Lauren Anderson (Flatiron Institute)
correlation What I want to do: Re-compute Eilers’ plot for galactic bars formed through two different scenarios: 1) In-situ (E. D’Onghia’s simulations) 2) Sagittarius impact (C. Laporte simulations) What I hope to learn: How long is the Milky Way’s Galactic bar? How did it form? (optimistic question) Which orbits support the bar? (using APOGEE/Gaia 6D info) What can we learn about the bar from APOGEE metallicities? You can ask me about: - Galactic dynamics/the Galactic bar - Orbit integration - Using Price-Whelan’s Gala package I’d like to chat about: - APOGEE selection function - The Galactic bar in general Flatiron Institute, Center for Computational Astrophysics
Variability for evolved stars. ❖ Galactic structures characterization (arms & bar) What I want to do What I want to learn What I bring What I like to discuss ❖ Radio astrometry at 1μas resolution. ❖ Experience generating simulated astrometric data. ❖ Radio data that complements Gaia results in the GP ❖ How variability can be obtained from Gaia ? ❖ How extinction maps are used over Gaia data? ❖ Generate MLE to test the Gaia limits ❖ Members of stellar association ❖ Synergies between astro- metric campaigns at different λ ❖ Stellar population across the GP ❖ Future missions in IR?...plausible?
do: Explore the non-axisymmetric & disequilibria structure in the Gaia data What I want to learn: How to differentiate between signatures of bars/spirals/external perturbers What I bring: Dynamical Galaxy modelling methods / knowledge; N-body, Test particle, Action-Angle (and models themselves), with various bars+spirals What I’d like to discuss: Reconciling long/short bar evidence, I don’t mind who’s right, I’d just like to know!
bimodality in Latte simulations, connection with stellar kinematics (and ages), test this formation scenario with Gaia++ ★ convince you to use our (really Robyn’s) Ananake synthetic Gaia DR2 catalogs from our Latte simulations to learn ★ how better to compare kinematics, abundances, and ages from Gaia + APOGEE + ??? against simulations bringing/sharing ★ Ananake synthetic Gaia DR2 catalogs and full snapshots of Latte simulations (i.e. I am happy to point you in Robyn’s direction) ★ sarcasm to discuss ★ joint analysis of abundances + kinematics + ages Andrew Wetzel (UC Davis)
theory • Impact of LSS on galaxies Would like to learn more about • GAIA’s constrain on DHs • Who wins, when, where in driving galaxies’ fate? What I bring • Understanding(?) of LSS + secular. dynamics Do discuss • What can be done with GAIA streams/ridges? Happy to work with anybody interested... What I want to do • Modify kinetic theory for streams • Map ridges in Gaia coordinates • Convince people quasi-linear theory rocks
qualities of the kinematic background in the solar neighborhood from the nearby clusters University of Wisconsin-Madison; 4th year undergraduate student working with Elena D’Onghia What I bring: • I bring a clustering algorithm (SNN) that can group stars together based on a variety of attributes (position, velocity, chemistry, etc.) that was developed in our group. • I bring some data structures and analysis experience from my CS background. What I want to learn: • I want to learn about the kinematic features of our solar neighborhood, and spiral galaxies in general. • I would like to learn the ages and metallicities of the clusters in the solar neighborhood to differentiate them from the background
with Elena D’Onghia What I want to do: I am interested in understanding the Arcturus moving group - its members and origin. I am hoping to be able to rebuild the group so that I may argue for either in situ or extragalactic formation. What I want to learn: Ages and metallicities of known Arcturus members as well as other clustering techniques. What I bring: Clustering algorithm (SNN) developed in our group, previously used for kinematic and chemical clustering for globular clusters and now modified for clustering in Gaia data - proper motion, ra, dec, and parallaxes.
understanding the formation of moving Pleaides, Coma Berenice (with Patrick LaChance) and on Arcturus moving group (with Alexandra Borukhovetskaya) I want to learn about ages and metallicities of moving groups and the open clusters I bring dynamical models with N-body simulations and experience on galactic dynamics
would like to produce useful “Gaia Gold Catalogs” for quasars, single stars and white dwarfs. Or something cooler with Anderson. Maybe some BHBs? What I want to learn: The pitfalls of producing such catalogs; particularly how to best cut the Gaia data What I bring: broad interests and expertise What I want to discuss: I will want to discuss anything
on binned velocity and tracer density data → -Apply to Jeans Equations to derive force maps and/or disequilibria maps (Δ-Jeans method from Sprint 2018), working with Lauren Anderson & Larry Widrow. Learn: Anything GP related. Selection functions. Bring: Broad Dark Matter knowledge (indirect, direct detection etc). Expertise in Jeans Modelling. Oscar - brute force tool for binning Gaia data incorporating full uncertainties. Discuss: Dark matter. GPs. Future measurements of stellar accelerations with high precision spectrographs & nano-arcsecond astrometry (1812.07581). V R V R V R V Z V Z V Z
wide co-moving pairs in data (>2 pc) tell us about whether stars are born together? Want to learn about: hierarchical star formation. Can help with: the lifecycle of star clusters born in the disk, clustering algorithms. Would like to discuss: the ISM! And what we can learn about clustered star formation from Gaia. A simulation of all stars born in star clusters in the Milky Way disk in the last 5 Gyr that includes a realistic potential (bar + spiral + GMCs) and a subgrid model for cluster birth and evolution
stuff + Gaia RR Lyrae completeness maps, PyMGC3, Galstreams library - compilation of MW stream footprints What I want to do: • Calibrate MG for RR Lyrae stars as a function of period-shift (location on Period-Amplitude diagram) OoII RRLs are brighter than OoI: ~0.25mag = 10% in Distance What I want to learn: • Statistical tools to deal with error systematics & correlations What I want to discuss: • New analytical models for the disc’s density profile to replace double exp+flare+warp
Build a “Gaia for beginners” catalogue, intended for use in, e.g., astronomy education (thanks Juna for suggesting this!) • Gaia DR2 sub-sample cleaned from the nasty bits, documentation, warnings on limitations What I want to learn • Can the “phase spiral” really be explained as due to moving groups (arXiv:1903.08325)? What I bring • Gaia expertise: all aspects of the data, quality filtering, archive access, ... What I want to discuss • Your thoughts on future Gaia data releases • How to preserve sufficient likelihood information in long term Gaia archive • Gaia selection function: your inputs on a good proposal to fund this effort • Uncertainties/systematics: how will these affect cross-calibration of other/future surveys against Gaia?
me about: distances to APOGEE red giant stars, Gaussian processes, the Milky Way’s circular velocity. sprint idea: find, map & model non-axisymmetric features of the Milky Way. I hope to learn about: Galactic bar, spiral arms, how to install galpy & calculate actions.
ask me about: SDSS-V the perfect spectroscopic match to Gaia... seeking collaboration on Gaia (DR2) as a time-domain survey: DR2 provides rms variations in flux, astrometric wobble, and v los (non-)variable WD candidates/contaminants rms fractional flux variation in G and their light-centroid wobble
using clustering algorithms - Estimate the shape of dark matter halo using hyper-velocity stars - Use orbits of runaway stars to identify their natal star clusters to learn - Clustering algorithms - Density distribution of young stars (<10Myr) in simulations. - Chemistry/age of known young massive clusters (e.g., Westerlund 1). - Basics on photometric metallicity - Why sometimes, two mathematically equivalent ADQL queries take very different times. - (E.g., “Select ra from AAA where (ra < 10)” and “Select ra from AAA where (ra - 0.5 < 9.5)”) - Any tips for reducing the ADQL query times. - Does anyone use astroquery? Is there any ways to run ADQL queries other than Gaia archive? to bring - Knowledge on hyper-velocity stars / runaway stars - Practical use of AGAMA code to discuss - Gaia Sausage / Disc substructure (e.g., Hercules stream) - Any bold ideas using Gaia data Kohei Hattori (University of Michigan)
collective effect of Galactic dark matter substructure on stellar velocity/acceleration fields (dynamical + lensing-induced) • Look for this pattern in Gaia DR2 What I want to learn: • Working with Gaia data! • Estimators and techniques to look for structure in 3D vector fields, accounting for uncertainties (e.g., extensions of 2-point correlations) What I bring: • Background in astrophysical signatures + particle physics properties of dark matter • Experience in writing fast Python code What I’d like to discuss: • Particle physics implications of DM substructure (population) measurements Substructure lens-induced... … velocity field … acceleration field
what the end of the main sequence in Gaia looks like and find new objects (young especially!) Learn: About hypervelocity stars in vtan space Bring: The end of the main sequence and science visualization Discuss: Visualizing our data!
>> white dwarf H-R diagram • Explain the Q branch • WD-WD merger rate What I want to learn >> optimal quality cuts; selection function; dust within 250 pc What I bring >> • white dwarf knowledge: cooling, merger, spectra, ... • experience in DR2 light-curves (effect of extended sources) • scanning directions of Gaia What I’d like to discuss >> • Gaia selection function • Gaia-Panstarrs cross-matching • bifurcation of Sagittarius Stream • spiral arms in stellar mass / gas ...
Determine luminosities of pulsating stars ★ Search for stellar clusters w. EMSTOs and fit isochrone clouds Johnston+2019 Victoria Antoci Want to learn ★ Application of Gaia astrometry and photometry to stellar clusters ★ Cluster membership verification Ask me about ★ Asteroseismology/seismic modelling of pulsating (massive) stars ★ Internal mixing and impact on stellar evolution and surface abundances Isochrone Cloud
shell structure in Virgo and related halo substructure want to learn: Is the shell structure in Virgo the same as the Gaia-Enceladus/Gaia-sausage merger and how old is that structure? bringing: Expertise in structure of the Milky Way halo and disk. want to discuss: How do we fit N-body simulations to Milky Way shell structure?
do >> Map non-axisymmetries in the disk with red-giant stars. >> Dynamically model the GD-1 spur. What I want to learn >> How to classify stellar variables using Gaia noise information. What I bring >> Expertise in computational data analysis, linear algebra, Bayesian inference, model building, MCMC. >> Knowledge about SDSS, BOSS, APOGEE, HARPS, Kepler, and Gaia. What I’d like to discuss >> Hierarchical models. >> The Gaia likelihood function. >> Mapping the dark matter. >> Chemodynamics. >> Binary stars.
do - 3d bulge (chemo-) dynamics with Gaia RVS M giants. Photometric metallicities → distances. What I want to learn - kinematic differences between metal-rich & metal-poor populations across bulge. What I bring - knowledge on ages/distances from Gaia+spectro, action-angles, streams, bar/bulge. What I want to discuss - 3d extinction mapping, photometric metallicity/ages, RVS selection fn, bar’s impact on SN kinematics. Li et al. 2016 Metallicity WISE colour
do: Characterize the kinematic signature of the Galactic stellar warp using APOGEE and Gaia data-sets. What I want to learn: I noticed that recent works are pointing out new ways of using Gaia flags. I would be interested to have a discussion with Gaia experts about it. What I bring: Knowledge and experience working with APOGEE, GALAH and RAVE data, this can be useful for this meeting. What I want to discuss: Stellar multiplicity using different RV visits in RAVE.
satellites affect the gas & stellar disk ? Including new satellites discovered by Gaia Expertise: • SPH & test particle simulations, galactic dynamics, variable stars Want to discuss: happy to discuss anything! Levine, Blitz & Heiles 06 Chakrabarti & Blitz 09
select metal-poor stars by combining broadband colors from Gaia and other all-sky surveys What I want to learn about: Efficiently cross-matching large catalogs, spectroscopic surveys covering bright (V<14) stars What I bring: Knowledge of dwarf galaxies and stellar streams (in Gaia and elsewhere). Beginner’s ability to model orbits with galpy. Other things I want to talk about and/or work on: Dwarf galaxies, stellar streams 1962 version: Wallerstein (1962) 2019 version?
for anomalous RV measurements using ensemble learning ★ Predict RV measurements for stars without measurements ★ Also very interested in the DR2 Time-Series Catalog and variable star classification Hope to Learn: ★ Systematics in the Gaia RV Catalog ★ Edge detection and clustering methods Bringing/Ask me About: ★ ADQL Queries ★ Database Crossmatching ★ Representation ML ★ Time Series Featurization Want to Discuss: ★ Gaia in the time domain, in DR2 and future DRs ★ Detecting variability using static data
M31 HII regions using biased Gaia astrometry • Star cluster properties accounting for small field correlations Morgan Fouesneau Max-Planck Institute for Astronomy What I would like to learn this week • Estimating Gaia’s small field of view correlations • Feedback on Gaia mock and GDR2. • Crossmatching catalogs including SED information I Can help with • Gaia data, crossmatch & data query helpdesk • Gaia Mock / Gaia classification & APs • GDR3 BP/RP spectra firstname.lastname@example.org @mfouesneau mfouesneau.github.io
structure. Impact of spirals/bars/companions on ISM/SF processes. Aim to do: • Look at galactic scale velocity fields, how they compare to sims. with different asymmetries/underpinning physics. Specific knowledge of: • Hydro+N-body simulations of galaxies, ISM physics. Would be keen to know more about: • Any aspect of the obs. data really (not touched it before!), phase spirals, models people are desperate in need of. ...What I don’t want to talk about: • Brexit. Please... just let it end. Do ISM features align with any stellar pops? ISM in a spiral Makes some stars... Alex Pettitt ?
wide binary luminosity ratios? - Hardening of close binaries in hierarchical triples - Test MOND with wide binaries Bring: binaries, white dwarfs, cosmological simulations, enthusiasm, short attention span Learn: how to use Gaia as a time-domain survey
measure proper motions, map density, look for extensions in RR Lyrae Want to learn: More about Gaia systematics, RR Lyrae, reliable density mapping of streams Bringing: Experience working with DES data, cross-matched dataset, tools for working with streams, experience with stream detection, photometric filtering, proper motion measurement Want to discuss: Dark matter constraints with streams, differences in globular cluster/dwarf stream populations Nora Shipp (UChicago)
spatial variation of kinematic properties in the halo with RR Lyrae What I want to learn: Modeling Gaia systematics; computationally efficient Bayesian inference methods for use with large datasets What I bring: Expertise in proper motions with HST; spectroscopic analysis; Bayesian inference (incl. hierarchical and mixture modeling) What I’d like to discuss: Methods for combining multiple datasets; chemodynamics; data-model comparison tools
*joint with Alex Malz (NYU; he is remote due to impending thesis defense but will Skype in when possible) ➔ Improve HR Diagrams for open clusters by identifying and correcting double stars, with the goal of creating a fully probabilistic model for HRD What I want to learn: ➔ A lot more about good models for HRD and also some stellar models that could be combined? ➔ Stuff about open clusters? -> What generates the HRD for clusters What I bring: ➔ A lot of knowledge about Gaussian Processes, especially for time-series analysis. Some crazy ideas about using GPs to speed up monte carlo, or even to get better information out of simulations (keywords: Multifidelity Monte Carlo, metamodels/emulators/simulators/etc.) (Want to get at what 1801.08547 marginalized over) [Widmark, et. al 2018] (First stab at PGM)
the orbit of a possible perturber of the GD-1 stream based on the kinematics of the perturbed region Bring: Python3 API for C, expertise in the detection and modeling of structures in the stellar halo Discuss: dating accretion events based on their structure in the space of conserved orbital properties
in action-angle space; inferring MW dust maps with DR2 + MA, age-abundance relations, realistic pipeline for time-series data; zoom-in simulations; - (Passionately): outline of a SOTA analysis, hierarchical inference, banish closed-form likelihoods? > Intend to: - (Warmup) DR2-APOGEE/SDSS x-matched data-sets to study chemo-dynamic properties of velocity ‘substructure’ (h/t: Myeong+’18, TCR’18). - Develop criteria for qualifying stellar population in a given volume patch as phase-mixed (h/t: BMH’09). > Experience: - with DR2 data and selection function based on gaia_tools (Bovy’16); - particle physics: indirect and direct DM detection; cooling rates for dissipative DM. - (Audaciously): Explore disequilibria with a semi-analytic forward modeling approach using simulations; toy n-body code that includes DM self-interactions.
modelling of a cluster - evidence beyond small (isotropic) dispersion? I want to learn about: ◦ stellar binaries and clusters ◦ hierarchical inference and clustering ◦ future data I bring experience with: Gaia data access and exploration and making interactive visualizations
do: Explore TESS-K2-Gaia synergy What I want to learn more about: Binaries in Gaia Gaia parallax systematics I bring experience with: Parallaxes beyond ~2-3kpc with red giants, asteroseismology, stellar models, APOGEE, Kepler, K2
Finish paper from last year’s Sprint. 2) Test+Map PS-spiral beyond 10 kpc without WEAVE or 4MOST with RC and a model to generate RVs complementing 5D data. LEARN Bayesian inference methods, data driven techniques, adaptive smoothing/filterning methods, AGAMA. BRING My pre-Gaia DR2 N-body models of Sgr impacting disc (free data). Useful for anyone doing disc-kinematics/bar kinematics? Familiar with studying kinematic substructure in SN, i.e. happy to help people (e.g. Elena’s team on Arcturus) if I can/it’s cool with y’all. DISCUSS “Existence of moving groups is not a physical explanation for the origin of the PS-spiral.” Happy to discuss/philosophise with Anthony Brown (maybe do a project?). Analogy: If I put re-assemble KFC chicken pieces (drum, breast, wings) into something looking like a chicken it doesn’t mean that KFC explains why chickens exist. Pre-Gaia simulations Gaia DR2 ?????????? ??????????
to do: Look for substructure signature in the Solar neighborhood using various tracer stars. Compare with results of cosmological simulations. Think about implications for dark matter detection. What I want to learn: Combining different catalogues (Gaia, RAVE, APOGEE). Modeling Gaia systematics. Knowledge of: hydro-dynamical simulations, chemo-dynamical models of the Milky Way and dwarf galaxies.
Latte halos for orbit studies, prep for public release of models Learning: how well we need to represent the MW to study its orbit structure; what else people want from mock observations Sharing: the ananke mock catalogs, dynamics expertise generally
I want to do: See what everyone is up to; extract physics from test particle simulations. What I want to learn: am currently GAIA curious - ready to take the next step. What I bring: Expertise in theoretical and computational astrophysics; some experience in test particle dynamics; a bit more in SPH/Moving-mesh/Eulerian hydro. What I want to discuss: Phase space mixing of stars, perturbation theory, etc.