Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006apj...636.1045l&link_type=abstract
The Astrophysical Journal, Volume 636, Issue 2, pp. 1045-1053.
Astronomy and Astrophysics
Astronomy
3
Line: Profiles, Ism: Planetary Nebulae: General, Ism: Planetary Nebulae: Individual: Alphanumeric: Ic 5117, Radiative Transfer, Scattering
Scientific paper
We report the discovery of He II λλ4850 and 6545 Raman-scattered by atomic hydrogen in the high-resolution spectrum of the very compact and young planetary nebula IC 5117 obtained with the ESPaDOnS (Echelle Spectropolarimetric Device for the Observation of Stars) installed on the 3.6 m Canada-France-Hawaii Telescope. By adopting case B recombination atomic data and considering all the fine-structure emission components, we calculate the weighted averages for the line centers of the Raman-scattered features, as well as those for the emission lines He II λλ4859 and 6560 to determine redward velocity shifts of Δv4850=+29 km s-1 and Δv6545=+24 km s-1. We compute the Raman conversion efficiency by a Monte Carlo technique adopting a simple scattering geometry, in which the hot central star is surrounded by a hollow cylindrical H I region characterized by thickness T that is in turn parameterized by the H I column density. It is proposed that the central far-UV emission region is covered significantly by the neutral scattering region characterized by the H I column density NHI~=4×1021 cm-2. The H I column density is higher by an order of magnitude than the value proposed from 21 cm radio observations. We briefly discuss the importance of Raman scattering as a probe of neutral material around a newly formed hot white dwarf and the mass-loss process occurring in the late stage of stellar evolution.
Ahn Sang-Hyeon
Jung Yang Chan
Lee Hee-Won
Song In-Ok
No associations
LandOfFree
Raman-scattered He II λλ4850, 6545 in the Young and Compact Planetary Nebula IC 5117 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Raman-scattered He II λλ4850, 6545 in the Young and Compact Planetary Nebula IC 5117, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Raman-scattered He II λλ4850, 6545 in the Young and Compact Planetary Nebula IC 5117 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1284301