Browsing and qualitative usage scenarios: GDAS-BR ------------------------------------------------- --- USECASE GDAS-BR-1 SCENARIO I'm completely new to Gaia. Tell me all about what is contained in the Gaia Archive, and give me some clear examples illustrating how it might be useful to my science. COMMENTARY Many archive systems present rich functionality but in a bewildering array of web pages that is most intimidating to the novice user. The Gaia Archive portal web pages should lead the first-time user gently by the hand via a well thought-out GUI. CONTRIBUTOR NigelHambly QUERY VOtables http://dc.zah.uni-heidelberg.de/__system__/tap/run/tableMetadata FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-3 SCENARIO I have a list of targets of interest from SDSS/UKIDSS/VISTA/PanSTARRS/whatever. For each one, give me the astrometric parameters (position at my specified equinox and epoch, proper motion, parallax and errors/quality statistics indicating the accuracy and significance of the data). COMMENTARY A fundamental usage of the Gaia catalogue CONTRIBUTOR NigelHambly QUERY "ADQL Query based on a list of objects feasible? YES! see http://dc.g-vo.org/tap/examples#applyICRScorrections TAP_UPLOAD.T1 AS u FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-4 SCENARIO I would like to have all the available Gaia measurements for all red giants (or whater type of physical object, such as galaxies, Qso, SSO and so on) COMMENTARY A less common type of query, but useful to help distributing big chunks of data to different astrophysical communities. CONTRIBUTOR Elena Pancino QUERY Typical ADQL query by type "Try Table gums.sn Table gums.quasars Table gums.galaxies in gums.mw, smc and lmc opjects can be filtered by alphafe, logg, mass, mbol, radius, teff and variabilitytype, amplitude, etc., the distance, FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-5 SCENARIO I want a pretty color picture for my powerpoint presentation, created using Gaia data. For example (first that comes in mind): I would like to select all stars belonging to the halo of the Milky Way and color them according to their 6D phase space information, assigning to each group its own colour. Then I want to project this on the sky either in ecliptic coordinates or whatever I choose, so that I can illustrate how the halo is structured and where the streams are, to make a picture like the one from the SDSS one, but with Gaia data (http://www.ast.cam.ac.uk/~vasily/sdss/field_of_streams/dr6/fos_dr6.jpg). I would also like to be able to put labels with the stream names and then save that picture in one of the most common formats, without having to actually download the data on my computer. COMMENTARY This is one type of service that would make astronomers life much better, and their presentations much nicer. CONTRIBUTOR Elena Pancino QUERY Topcat sort data by mualpha and mudelta weighted by distance Group BY Halo: Bahnelemente, z-geschw., RGB-Sterne in LMC FEASIBLE WITH VO-TOOLS? WAHR -- USECASE GDAS-BR-6 SCENARIO I liked the statistical plots presented in Section 3 of Volume 1 of the Hipparcos and Tycho Catalogues. Show me the same for Gaia and allow me to specify the statistic to explore. CONTRIBUTOR AnthonyBrown QUERY look at plots to be tested FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-7 SCENARIO I want data of all objects contained in a rectangular/circular region centered on a given sky position. COMMENTARY A basic search with the database. CONTRIBUTOR Laurent Chemin QUERY cone search ADQL, TAP, to be tested FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-8 SCENARIO I want data of all objects contained in a rectangular/circular region within (or at a) a given distance R from the Sun, or from any other star, and at a given distance z from the equatorial plane (z=0). COMMENTARY Another basic search with the database. The Galactic Centre could be proposed by default for the reference point. CONTRIBUTOR Laurent Chemin QUERY see USECASE GDAS-OA-15, to be tested, query for distance, distance to other star and z needs to be computed from position(alpha,delta) and distance and the position of the galactic plane. FEASIBLE WITH VO-TOOLS? WAHR * --- USECASE GDAS-BR-10 SCENARIO I would like to be able to select objects based on any set of the variables provided in the Gaia catalogue position, parallax, astrophysical parameters, proper motion uncertainties etc. These selections should not be limited to simple "axis-parallel"" cuts or cone cuts, but permit a broader array of functions/functional dependencies. An example is selection on fractional parallax error and some relation between G magnitude and extinction. Another is selection on space velocities, which requires a combination of position, parallax and proper motion. " COMMENTARY Many catalogue enquiry systems don't permit this level of sophistication, so you have to download the whole catalogue and process locally. This will not be possible with Gaia! CONTRIBUTOR Coryn Bailer-Jones QUERY seems to be standard job for ADQL, to be tested -> nicht triviale selektion FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-11 SCENARIO I would like to make selections of Gaia objects based not only on Gaia data, but also based on other major catalogues available at that time, such as Pan-STARRS and SDSS. COMMENTARY Gaia answers many but not all questions, and catalogues such as SDSS will remain a standard for years to come. Simple cross matching between Gaia and other major catalogues should be enabled. Better still, the "obvious"" (e.g. position/proper motion) it would be done by CU9 and already present in the accessible catalogue. CONTRIBUTOR Coryn Bailer-Jones QUERY see USECASE GDAS-BR-3, to be tested FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-12 SCENARIO I would like to be able to select those objects which show significant spectral features (emission lines or absorption lines) in the BP/RP. COMMENTARY Most BP/RP spectra exhibit only the shape of the spectral energy distribution because the absorption lines or emission lines are too weak for being detectable at the low resolution and limited S/N ratio of the BP/RP spectra. However, there are exceptions from the rule, e.g. Wolf-Rayet stars, quasars, and white dwarfs. I am in particular interested in a list of objects which show significant absorption in the BP at Hbeta and Hgamma. These would be good candidates for being non-radially variable ZZ Ceti stars. I should be possible to apply the search to individual or the summed-up spectra for a given object. CONTRIBUTOR Stefan Jordan QUERY SPLAT? FEASIBLE WITH VO-TOOLS? NO --- USECASE GDAS-BR-14 SCENARIO I would like to be able to visualise the Gaia catalogue - in multi-dimensional space - preferably utilising a visualisation engine such as Google Sky or World Wide Telescope - such that I can incorporate data from other surveys in to the same tool. CONTRIBUTOR NicholasWalton QUERY Aladin? Zooming and panning -> create queries FEASIBLE WITH VO-TOOLS? WAHR --- USECASE GDAS-BR-16 SCENARIO § Interactive plots (2D/3D zooming and rotation). The user will have the possibility to select any attribute for any axis and customize the plot in that way. o E.g. selecting mean values for color and magnitudes, the user can produce the HR diagram. "§ It should be possible to make a selection of points and store the set of sources for other plots or analysis. § Aggregated plots (Anthony Unwin, 2006). When the number of objects is huge, the data has to be aggregated for better visualization. Some kind of aggregation plots includes: · IQR plot · Histogram · Mosaic plots · Bubble plots · Density plots These aggregated plots are meant to analyze large sets of data without plotting detailed information for all sources. Note: These two approaches (Interactive plot driven analysis and aggregated plots) are complementary. The idea is to start with an aggregate plot to visualize 109 objects. When we increase the level of detail (subranges of attributes), we reduce the set of objects of interest and we will be able to make an interactive plot on those objects. o Specific operations on selected sources. § Run different period search methods with specific parameters on selected sources, retrieve the resulting periodogram/frequencygram and try different peaks/period candidates to fold and visualize a given light curve. (Discuss with Laurent) Run TBD CU7 algorithms in an interactive way. Users with specific granted permissions will be allowed to do that It should be possible to save and export data for any selection in some TBD formats. Also, it shall be possible to retrieve flux, times, flags and errors in ascii of the current source (These data can be imported in a different platform to produce a more detailed analysis. E.g R, Matlab, etc) " "Web Resources of currently implemented approaches for variability analysis in astronomy are: · Time Series Center: http://timemachine.iic.harvard.edu/ · NStED: Exo-Planet Transit Survey Kepler Search: http://nsted.ipac.caltech.edu/applications/ETSS/Kepler_index.html · Period04: http://www.univie.ac.at/tops/Period04/ · Sigspec: http://www.sigspec.org/ · PlotCurve: http://www.rssd.esa.int/SA/HIPPARCOS/apps/PlotCurve.html Bibliography Anthony Unwin, M. T. (2006). Graphics of Large Datasets. Visualizing a Million. (Statistics and Computing ed.). Springer. " CONTRIBUTOR Laurent Eyer QUERY to be tested, seems feasible with TOPCAT FEASIBLE WITH VO-TOOLS? WAHR *--- USECASE GDAS-BR-17 SCENARIO I would like to retrieve all pairs of stars with common proper motion. COMMENTARY The information from this would be very useful for identifying pairs of apparently isolated stars that may be a very wide double system or have a common origin. CONTRIBUTOR CarmeJordi QUERY select a.sourceid, a.mualpha, a.mudelta, b.sourceid, b.mualpha, b.mudelta from (select * from gums.mw where 1=CONTAINS(POINT('ICRS', alpha, delta), CIRCLE('ICRS', 10, 15, 1))) as a join gums.mw as b on ( a.sourceid