Near IR Spectroscopy of Symbiotic Stars and Young Planetary Nebulae. Hee -Won Lee ARCSEC and Dept. of Astronomy Sejong University 2010 August 26. Contents. Introduction to symbiotic s tars ans youn g PNs Mass Transfer and Mass Loss in Symbiotics Mass Loss and IR Observations of PNs
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ARCSEC and Dept. of Astronomy
2010 August 26
Planetary nebulae exhibit a variety of morphology from spherical, elliptical to bipolar and multipolar.
He NebulaeII, OVI
H I Scattering
RegionMass Loss and Mass Transfer in Symbiotics
1. Raman O VI features are well-fit by a Keplerian accreting flow with an additional absorbing or an emission component.
2. Needs to know the physical dimensions of the emission region and scattering region in order to obtain accurate mass transfer rate and mass loss rate.
3. Notoriously difficult to find the distance and the orbital parameters
BOES Data of V1016 Cyg
1. In RR Tel (the prototypical D-type symbiotic) and He 2-38, CO and H2O absorption at 2 micron are seen.
2. CO absorption bands are also found in HM Sge and V1016 Cyg, all of which exhibit prominent Raman scattered O VI.
3. Periodic IR flux variation expected from a Mira varibale.
4. Neutral atomic lines such as Fe, Sc, Ti may trace the stellar atmosphere of the cool giant.
S. Gemini IR spectroscopy of several IR spectroscopy by Fekel et al.
NGC 7293 (Helix)
3.2, 4.5, and 8.0 microns blue, green, and red
NGC 6543 Spitzer image
3.6 microns : blue, 5.8 microns green, 8.0 microns : red
Strikingly different shapes in optical and infrared.
H2 molecules are mainly found in the equatorial plane.
Different spatial distribution and kinematics.
The molecular component is important in bipolar morphology.
H2 was detected first in NGC7027.
Molecular hydrogen was detected in six planetary nebulae (Isaacman, 1984, UKIRT).
H2 spectra were interpreted by shock excitation.
4 . T=1000-2000 K,
5. H2 emission in M2-9, NGC 7027 is interpreted by UV fluorescence (Hora & Latter 1994, Graham et al. 1993)
H2 and Optical Composite
H-alpha (green) and O III (blue) gases from the Hubble Space Telescope.
Molecular hydrogen (red) from Spitzer observations at 4.5 and 8.0 microns.
Raman He II Monte Carlo profiles for various expanding velocities of the cylinder with fixed N HI and opening angles.
The Raman feature shows the shift of line center sensitively.
Stronger profiles are obtained for higher expansion velocity due to proximity to the resonance of the Raman scattering cross section.
Determination of HI expansion velocity region is possible from a Monte Carlo line profile analysis.