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The transition from AGB stars to PNe: a scientific case for the VO

The transition from AGB stars to PNe: a scientific case for the VO. P. García-Lario, A. Bayo & M. Sierra. ISO Data Centre, ESA-ESAC. The transition from AGB stars to PNe in the H-R diagram. Late evolutionary stages of low- and intermediate mass stars (1 - 8 M  ).

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The transition from AGB stars to PNe: a scientific case for the VO

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  1. The transition from AGB stars to PNe: a scientific case for the VO P. García-Lario, A. Bayo & M. Sierra ISO Data Centre, ESA-ESAC

  2. The transition from AGB stars to PNe in the H-R diagram • Late evolutionary stages of low- and intermediate mass stars (1 - 8 M) - Short transition times (~103 - 104 yr) - Recent AGB mass loss (up to 10-4 M/yr)  • Few objects in this phase - Many are heavily obscured in the optical  - Need of systematic surveys using infrared data

  3. From AGB stars to Planetary Nebulae Dramatic changes in: • pulsation properties • mass loss - chemistry - overall SED - morphology O- rich C- rich O- rich See video...

  4. Search for new transition sources using IRAS Pottasch et al. 1988; Preite Martinez 1988; García-Lario 1992 All-sky survey 250,000 Sources 4 bands 12, 25, 60 and 100 m PNe show characteristic IRAS colours! … but unidentified sources in the IRAS two-colour diagram were found to be transition sources rather than typical PNe

  5. Heavily obscured late-AGB stars OH 26.5+0.6

  6. Optically bright post-AGB stars IRAS 19114+0002

  7. Optically bright post-AGB stars IRAS 19114+0002

  8. Extremely young/dusty planetary nebulae IRAS 17347- 3139 +

  9. Extremely young/dusty planetary nebulae IRAS 17347- 3139 + HST-NICMOS

  10. How can we enlarge the sample? • IRAS had limited sensitivity and a poor spatial resolution (15”- 30”) 4 photometric bands centred at 12,25, 60 and 100 m (~250,000 sources) All-sky survey - but confusion close to the Galactic Centre Optical/near-infrared counterparts difficult to identify in crowded areas • Use of MSX data can help… 4 bands A,C.D.E centred at 8. 11, 14 and 21 m (~ 500,000 sources) Limited to |b|< 6 degrees but this is where most AGB to PN sources are located Much better spatial resolution than IRAS (1.5”-2”) Optical/near-infrared counterparts can be easily checked using DSS/2MASS data Not enough to disentangle YSOs and extragalactic sources from evolved stars

  11. Search for new transition sources using MSX Young PNe and transition sources are located in a well defined region of the diagram… …but there is a lot of overlap with YSOs Can we get rid of the ‘contaminating’ sources? …data must be complemented with IRAS photometry at 60 m

  12. An ideal case for the AVO • X-match catalogues (MSX and IRAS) containing ~105 – 106 sources • Catalogue manipulation: select/filter/add columns (A-C, D-60) • Query SIMBAD or other Vizier catalogues with lists containing ~ 104 sources to search for yet unidentified sources and/or get a classification for the identified ones • Create color-color diagrams where the position of different classes of sources can be visualized • On-the-fly display SEDs of specific sources including ALL available data in catalogues/data archives (spectroscopy+photometry) for automated classification or modelling SEE DEMO !!

  13. Gallery of extremely young planetary nebulae IRAS 22036+5306 Hen 3-401 Stingray Nebula IRAS 17395-0841 IRAS 16594-4656

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