| |
 |
| Paper: |
Raman Scattering of He II as a Unique Spectroscopic Tool of Atomic Hydrogen in Young Planetary Nebulae |
| Volume: |
536, The Twelfth Pacific Rim Conference on Stellar Astrophysics |
| Page: |
147 |
| Authors: |
Lee, H.-W.; Chang, S.-J. |
| Abstract: |
Young planetary nebulae are important objects to investigate the mass loss processes through Raman scattering of He II with atomic hydrogen. Strong He II far UV emissions are generated near the hot central star and subsequently enter the neutral region to be inelastically scattered by hydrogen atoms in the ground state to form optical emission features blueward of Balmer lines. In particular, He IIλ1025 line photons are Raman-scattered with a hydrogen atom in the ground state to be re-emitted at a line photon near 6545 Å. Thus far, the Raman-scattered He II features have been reported in the 6 young planetary nebulae NGC 7027, NGC 6302, IC 5117, NGC 6790, NGC 6881 and NGC 6886. We discuss the working principle of the differential gear as the mechanical analogue of Raman scattering. In a way similar to the stroboscopic effect, Raman scattering provides an opportunity to investigate the mass loss process in slow motion view. We introduce the Monte Carlo radiative transfer code ’STaRS’ to investigate the formation of Raman-scattered He II in the young bipolar planetary nebula NGC 6302. |
|
|
|
|
|
