Science in the Spanish Virtual Observatory

1. Enrique Solano LAEFF-CAB / INTA-CSIC SVO Principal Investigator Science in the Spanish Virtual Observatory

2. Outline EuroVO-AIDA workshop. ESAC Dec 08 • How can VO help astronomical research? • What kind of research is easier/more efficient in the VO framework? • Science and the VO projects • (Spanish)-VO papers

3. VO and astronomical research EuroVO-AIDA workshop. ESAC Dec 08 Science Tools Stds • What can VO do for science? • Foster new and/or more efficient science. • How? • Facilitating the work of astronomers in fields like: • Data discovery, access, retrieval and analysis • VO standards and tools

4. Science that benefits from VO EuroVO-AIDA workshop. ESAC Dec 08 • Multiwavelength astronomy • Identification of “exotic” objects

5. Science that benefits from VO EuroVO-AIDA workshop. ESAC Dec 08 • Multiwavelength astronomy • Searching the pieces. • Retrieving the pieces.

6. Science that benefits from VO EuroVO-AIDA workshop. ESAC Dec 08 • Multiwavelength astronomy • Putting the pieces together.

7. Science that benefits from VO EuroVO-AIDA workshop. ESAC Dec 08 • “Exotic” objects • Cross-correlation among archives with millions of observations. • Data transfer for their local analysis unfeasible • Limitations in bandwidth • Storage --> Definition of a backup policy • Need for databases. Searched based on indexes. • Remote analysis. Transfer of results instead of data.

8. Science that benefits from VO EuroVO-AIDA workshop. ESAC Dec 08 • “Exotic” objects and the VO

9. Science and the VO projects EuroVO-AIDA workshop. ESAC Dec 08 • A concern for VO projects

10. SVO: Support to VO Science EuroVO-AIDA workshop. ESAC Dec 08 • VO is something new. • If the services developed by the VO are not scientifically oriented, they will not be used by the scientific community. • Goal: Liaison between SVO and research groups who have identified scientific drivers to motivate the adoption of a Virtual Observatory methodology in their science cases • SVO role: • Evaluation of the science case from the VO point of view. • Provision of information about the existing VO tools. • If needed, develop new tools.

11. SVO: On-going projects EuroVO-AIDA workshop. ESAC Dec 08 • Identification and characterization of ultracool objects. • Characterization of stellar & substellar population in clusters. • Identification of hot subdwarfs.

12. EuroVO-AIDA workshop. ESAC Dec 08 • Brown dwarfs: link between low-mass stars and planets. • The formation process is still a matter of debate: • Scenarios: • Photo-erosion of massive prestellar cores by nearby ionising stars (Whitworth & Zinnecker 2004) • Only operate in the vicinity of a massive star. Cannot be a major source of BDs. • Ejection theory (Reipurth & Clarke AJ, 2001): BDs are leftovers of a prematurely interrupted accretion process. BUT • High velocity dispersions  No disks

13. EuroVO-AIDA workshop. ESAC Dec 08 • Star-like (fragmentation and collapse of a molecular cloud.) • Supersonic turbulence in molecular clouds may generate a complex density field with large contrast  BD mass cores gravitationally unstable (Padoan & Nordlun, ApJ 2004). • Fragmentation of massive extended discs around Sun-like stars of the outer parts of the stellar disks (Stamatellos et al., MNRAS’07,’08) • Released into the field by interactions among themselves. • Low velocity dispersion (< 2 km/s)  ability of retaining the disk  IR excess and accretion. • Can explain the brown dwarf desert, i.e. the lack of close BD companions to Sun-like stars.

14. EuroVO-AIDA workshop. ESAC Dec 08 • Search young BD by cross-correlating IPHAS and 2MASS • Outside SFRs (for the first time) • 1600 square degrees • Filtering using appropriate color criteria. • Methodology: Aladin in script mode • Handling large area regions leads to memory problems. • Mosaic of 30’ radius regions.

15. EuroVO-AIDA workshop. ESAC Dec 08 • Follow-up of 113 candidates. 33 spectroscopically confirmed.

16. EuroVO-AIDA workshop. ESAC Dec 08 • New cross-match using the IPHAS Initial Data Release (González-Solares et al. 2008). • PhotoObjBest: observations in good photometric conditions and with good photometric calibration. • Follow-up spectroscopic observations have been requested in two telescopes. • Spatial distribution: association with molecular clouds

17. EuroVO-AIDA workshop. ESAC Dec 08 • λOri SFR: 400 pc, low extinction (Av~0.36 mag) in the inner area.

18. EuroVO-AIDA workshop. ESAC Dec 08 • Goal: Physical parameters (Teff, bolom. luminosity, mass and age) of candidate members using SED fitting. • Compilation of the available multi-λinformation. • Comparison with different collection of models. • Tedious and time consuming

19. EuroVO-AIDA workshop. ESAC Dec 08

20. EuroVO-AIDA workshop. ESAC Dec 08 • Upper-limit of 12.3-16 Myr (consistent with the estimated ages for the cluster by other authors). • Other physical parameters also in good agreement with prev. determinations. • 20 minutes for the whole workflow.

21. EuroVO-AIDA workshop. ESAC Dec 08 • Similar study in Taurus using UKIDSS, Spitzer and optical data.

22. EuroVO-AIDA workshop. ESAC Dec 08 • Identification and characterization of new regions to search substellar objects. • BDs are much brighter when younger… BUT • Young clusters have variable extinction • σ Ori: young (3 Myr), close (390 pc) and free of extinction (Av < 0.3 mag)

23. EuroVO-AIDA workshop. ESAC Dec 08 Tycho-2 / 2MASS correlation • Members: Signsposts of youth • O,B, LiI in absorption, strong X-ray or Hα emission, IR excess. • Unknown status: • Proper motions and small deviations from the young-star seq.

24. EuroVO-AIDA workshop. ESAC Dec 08 DENIS / 2MASS correlation • Boundary determination • Candidate characterization. Removal of: • Foreground and reddened background sources • Extended objects

25. EuroVO-AIDA workshop. ESAC Dec 08 • Catalogue of 509 confirmed and candidate young stars and brown dwarfs. • Characterization of the mass function from 15 to 0.07 solar masses. • Excellent starting-point for further, follow-up dedicated studies. • Spatial distribution, presence of disks,… Intensive use of VO for data discovery and characterization

26. And as a bonus… EuroVO-AIDA workshop. ESAC Dec 08 • CPD-20 1123 (1896) • TYC 5940 962 1 (2000) • 2MASS J06061339-2021072 (2003).

27. Hot subdwarfs EuroVO-AIDA workshop. ESAC Dec 08 • Originally classified as the brightest white dwarf in the last 40 years, it turned out to be a very rare object: a bright He-B subdwarf.

28. Hot subdwarfs EuroVO-AIDA workshop. ESAC Dec 08 “(He-sdB) stars are extremely rare hot subluminous stars whose existence cannot be explained by canonical stellar evolution theories nor by normal sdB evolution.” (Ahmad, 2004) • Identification of new hot subdwarfs. • Data Mining tools to distinguish them from WDs and CVs • Characterisation using asteroseismological information from COROT and Kepler. SEA Scientific Meeting, July’08

29. Conclusions EuroVO-AIDA workshop. ESAC Dec 08 SVO: 4 / 12 (2007-08) • The Virtual Observatory • Discovery tool • Capable of analyzing large, worldwide-distributed data sets • Now it’s time to demonstrate that it works!! • Strength the links between the VO community and the astronomical community is compulsory.

30. The Spanish VOhttp://svo.laeff.inta.es EuroVO-AIDA workshop. ESAC Dec 08 • 10 FTEs + Network of almost 100 researches from 17 centres. • Lines of work: • Management of VO-compliant archives • Development of VO-tools (including Data Mining tools). • Support to VO-Science  Key aspect in the project.