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Science in the Spanish Virtual Observatory Enrique Solano LAEFF-CAB / INTA-CSIC SVO Principal Investigator Outline 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 EuroVO-AIDA workshop. ESAC Dec 08 VO and astronomical research What can VO do for science? Science Foster new and/or more efficient science. How? Tools Facilitating the work of astronomers in fields like: Data discovery, access, retrieval and analysis Stds – VO standards and tools EuroVO-AIDA workshop. ESAC Dec 08 Science that benefits from VO Multiwavelength astronomy Identification of “exotic” objects EuroVO-AIDA workshop. ESAC Dec 08 Science that benefits from VO Multiwavelength astronomy Searching the pieces. Retrieving the pieces. EuroVO-AIDA workshop. ESAC Dec 08 Science that benefits from VO Multiwavelength astronomy Putting the pieces together. EuroVO-AIDA workshop. ESAC Dec 08 Science that benefits from VO “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. EuroVO-AIDA workshop. ESAC Dec 08 Science that benefits from VO “Exotic” objects and the VO EuroVO-AIDA workshop. ESAC Dec 08 Science and the VO projects A concern for VO projects EuroVO-AIDA workshop. ESAC Dec 08 SVO: Support to VO Science 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. EuroVO-AIDA workshop. ESAC Dec 08 SVO: On-going projects Identification and characterization of ultracool objects. Characterization of stellar & substellar population in clusters. Identification of hot subdwarfs. 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 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. 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. EuroVO-AIDA workshop. ESAC Dec 08 Follow-up of 113 candidates. 33 spectroscopically confirmed. 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 EuroVO-AIDA workshop. ESAC Dec 08 λOri SFR: 400 pc, low extinction (Av~0.36 mag) in the inner area. 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-λ information. Comparison with different collection of models. – Tedious and time consuming EuroVO-AIDA workshop. ESAC Dec 08 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. EuroVO-AIDA workshop. ESAC Dec 08 Similar study in Taurus using UKIDSS, Spitzer and optical data. 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 mag) EuroVO-AIDA workshop. ESAC Dec 08 (Av < 0.3 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. EuroVO-AIDA workshop. ESAC Dec 08 DENIS / 2MASS correlation Boundary determination Candidate characterization. Removal of: Foreground and reddened background sources Extended objects 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 EuroVO-AIDA workshop. ESAC Dec 08 And as a bonus… CPD-20 1123 (1896) TYC 5940 962 1 (2000) 2MASS J06061339-2021072 (2003). EuroVO-AIDA workshop. ESAC Dec 08 Hot subdwarfs • 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. EuroVO-AIDA workshop. ESAC Dec 08 Hot subdwarfs “(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) SEA Scientific Meeting, July’08 Identification of new hot subdwarfs. Data Mining tools to distinguish them from WDs and CVs Characterisation using asteroseismological information from COROT and Kepler. EuroVO-AIDA workshop. ESAC Dec 08 Conclusions The Virtual Observatory Discovery tool Capable of analyzing large, worldwide-distributed data sets SVO: 4 / 12 (2007-08) Now it’s time to demonstrate that it works!! Strength the links between the VO community and the astronomical community is compulsory. EuroVO-AIDA workshop. ESAC Dec 08 10 FTEs + Network of almost 100 researches from 17 centres. The Spanish VO Lines of work: http://svo.laeff.inta.es Management of VO-compliant archives Development of VO-tools (including Data Mining tools). Support to VO-Science Key aspect in the project. EuroVO-AIDA workshop. ESAC Dec 08