Breakout A: Survey Science, understanding the Milky Way
Breakout A: Survey Science, understanding the Milky Way
- Topic Areas
- Conclusions from Group A: GREAT Working Group Areas:
- Contributed material/Discussions
Location: Sackler Lecture Theatre - the Hoyle Building
Session Coordinators: Sofia Feltzing and Nicholas Walton
- Origin, structure, and evolution of the Milky Way
- Galactic Dynamics
- Galactic Archaeology
Conclusions from Group A: GREAT Working Group Areas:
- provide input to the modeling community with latest on Gaia expected performance
- compare models of galaxy structure - kinematics, dynamics, hydrodynamics, chemistry
- compare models with new survey data
iterate with incoming Gaia data > improve models
- what is available when?
- questions of optical / IR / other wavelengths / all sky data
- merging of data
- example solid science case(s) defining need for ESO GB facilities
- time urgency on this
- tidal streams
- SN - feeds into cosmology
- best practise in followup
- stellar / solar system overlaps
- potential of Gaia for galaxy evolution studies, AGN variability, bright QSO's
Interface to other breakout sessions
- synthesis of science cases
Additional points to note
New Statistical Techniques the requirements from the above will require use of new IT / data handling / access techniques > use and new possibilities from IT advances
Underpinning fundamental science from Gaia: distance scales
Interface to Gaia - ESA and DPAC
- input into, interface to, CU9 - other relevant DPAC ativities
- set up wiki pages for the WGs above
- identify/ confirm interested participants and 'facilitators'
- need for workshops, mailing list - online activity
major conference - late 2010 - The Promise of First Science from Gaia
- Evangelos Kontizas
- William O'Mullane
AndreasKorn (Friday only)
- Daisuke Kawata
- Carla Cacciari
- Gisella Clementini
- Xavier Luri
- Mike Irwin
- Gerard Gilmore
- Annette Ferguson
- Mark Wilkinson
- Walter Dehnen
- Antonella Vallenari
- Mark Cropper
Key Science Themes
- Galaxy Modeling
- Galaxy Evolution (SFH)
- Streams and sub structures
- Distance Scale
- dSph - abundances, pop III
- How do galaxies form?
- Nature and distribution of dark matter (energy)?
- clumpiness, stars
- Distribution/ structure of stars, gas (need different techniques to map this c.f. dark matter)
- Make sense of the current and future surveys
- the data - information - knowledge - understanding cycle.
- there will be a lot of information (e.g. catalogues) - how do we combine this information
How to exploit Gaia
- need RV studies
- need IR data to understand low latitude structure
- need photometric data
- feed this into a 3-D model (extinction maps in 3-D - these are being refined - e.g. from Galactic plane surveys - which promise detailed extinction maps with inclusion of IR surveys)
- need to feed this into a model - which in turn provide a predictive function
- need iteration - model - data - improve model - more data - better model
- WD: catalogue is raw info - several levels of understanding - requiring a dynamical model for inferring dark matter distribution
- AR: method - how to change the model to adapt to the accumulation of data - thus model convergence.
- Models - coarseness, fine (model) structure - dynamics - dynamics of the local group
- Models must explain the here and now
- JB: refer - JD5 at GA2009 - modeling the galaxy
- How many models? a model?
- Models work in the context of data - need to work with simulations (and simulated data) now - to be prepared for the inclusion of Gaia data.
- comparison of models - use of gaia simulated data (definition of what information from Gaia is required by the external modelers).
- GUM - billion star simulation of what gaia will observe - but it is not a full dynamical model]
'Highlight': define requirements of modeling community - update information on what the Gaia catalogue will give - errors etc
'WG' on model - gaia interface]
- PanSTARRS - will be public data in 2015?
- are the data available for the galaxy (as required for model / understanding)
'WG' on supporting multi-wavelength data resources (analysis of what are the gaps).
(question of how to treat local group galaxies - and the extragalactic story - unresolved galaxies, qso's, AGN variability etc - and the dark matter)
Pre - and post supplementary data
Range of requirements for observational programmes - range of R's for instance - depending on whether one is looking for s process, r process, Fe, Mg, etc etc.
WG - 'Chemical Tagging' as an example science driver (links to Archaeology) - what imaging/ spectroscopy is required. does this need a new instrument.
Mag cuts < 16 and > 16 - issues for follow-up.
small workshop of interested scientists to define specific science case and requirements which flow from that.
'WG' - alerts - SN - how does the followup process work - what sort of response network is required?
Gaia for the extragalactic community
advertise what information Gaia would provide on galaxies - photometry and positions. coverage. use of the SN for cosmology
localisation of the bright end of the QSO luminosity function (which in turn become probes of the ISM).
'WG' on use of Gaia for extragalactic research.
many large facilities being planned are closed consortia initiatives (e.g. WFMOS, PanSTARRS, APOGEE)
thus - how to identify the main European level priorities - and look to gain access to the required telescope/ instrumentation.
modeling - dynamics c.f. kinematics
Resolution and S/N required to meet the key science drivers.
tradeoff of all sky coverage vs targeted samples
measurements of tracers of the halo, the disk.
chemical tagging - what resolution is required - 10000? Use of chemical tagging to disentangle components of the galaxy (e.g thin - thick disk).
Gaia - what Teff, Log g, Z will it give - what else is required.
ESO are already indicating that large Gaia related survey programmes would be welcome.
HST had the ground breaking HDF observations - is there something similar that could come out of Gaia - a flagship science question
Follow-up in terms of detailed elemental abundances: I believe that there is a need to address the type/quality of any follow up observations that deal with high resolution spectroscopy. Gaia will, obviously, provide a great way to define new samples for deeper studies. However, how do we go forward in terms of the equipment we need etc (eg what size of telescopes, what resolution, automated abundance analyses?). Perhaps GREAT could provide a platform to create working groups and do smaller workshops where some of these issues are discussed in detail and then the knowledge gathered used for a more coherent campaigning for the observing facilities needed and how to make the best use of those available. We might in the end need the very detailed information provided by high-resolution spectroscopy to crack some of the puzzles that the Milky Way is posing and where the broad sweeps of the surveys do not give the whole picture.
Paris Observatory: GREAT-ObsPM-A.txt
University of Barcelona: University_Barcelona_GREAT.pdf