CrossCalibration Status Overview

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
O- rich
C- 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 26.50.6
6
Optically bright post-AGB stars
IRAS 191140002
7
Optically bright post-AGB stars
IRAS 191140002
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 blt 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 (spectroscopyphotometry) for automated
  classification or modelling

SEE DEMO !!
13
Gallery of extremely young planetary nebulae
IRAS 220365306

Hen 3-401
Stingray Nebula
IRAS 17395-0841
IRAS 16594-4656