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Title: IMAGING THE ELUSIVE H-POOR GAS IN THE HIGH adf PLANETARY NEBULA NGC 6778

Abstract

We present the first direct image of the high-metallicity gas component in a planetary nebula (NGC 6778), taken with the OSIRIS Blue Tunable Filter centered on the O ii λ 4649+50 Å optical recombination lines (ORLs) at the 10.4 m Gran Telescopio Canarias. We show that the emission of these faint O ii ORLs is concentrated in the central parts of the planetary nebula and is not spatially coincident either with emission coming from the bright [O iii] λ 5007 Å collisionally excited line (CEL) or the bright H α recombination line. From monochromatic emission line maps taken with VIMOS at the 8.2 m Very Large Telescope, we find that the spatial distribution of the emission from the auroral [O iii] λ 4363 line resembles that of the O ii ORLs but differs from nebular [O iii] λ 5007 CEL distribution, implying a temperature gradient inside the planetary nebula. The centrally peaked distribution of the O ii emission and the differences with the [O iii] and H i emission profiles are consistent with the presence of an H-poor gas whose origin may be linked to the binarity of the central star. However, determination of the spatial distribution of the ORLsmore » and CELs in other PNe and a comparison of their dynamics are needed to further constrain the geometry and ejection mechanism of the metal-rich (H-poor) component and hence, understand the origin of the abundance discrepancy problem in PNe.« less

Authors:
; ; ; ;  [1];  [2]
  1. Instituto de Astrofísica de Canarias, E-38200, La Laguna, Tenerife (Spain)
  2. Instituto de Física e Química, Universidade Federal de Itajubá, Av. BPS 1303-Pinheirinho, 37500-903, Itajubá (Brazil)
Publication Date:
OSTI Identifier:
22654292
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 824; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; COMPARATIVE EVALUATIONS; EMISSION; FILTERS; METALLICITY; MONOCHROMATIC RADIATION; PLANETARY NEBULAE; RECOMBINATION; SPATIAL DISTRIBUTION; STARS; TELESCOPES; TEMPERATURE GRADIENTS

Citation Formats

García-Rojas, Jorge, Corradi, Romano L. M., Jones, David, Rodríguez-Gil, Pablo, Cabrera-Lavers, Antonio, and Monteiro, Hektor. IMAGING THE ELUSIVE H-POOR GAS IN THE HIGH adf PLANETARY NEBULA NGC 6778. United States: N. p., 2016. Web. doi:10.3847/2041-8205/824/2/L27.
García-Rojas, Jorge, Corradi, Romano L. M., Jones, David, Rodríguez-Gil, Pablo, Cabrera-Lavers, Antonio, & Monteiro, Hektor. IMAGING THE ELUSIVE H-POOR GAS IN THE HIGH adf PLANETARY NEBULA NGC 6778. United States. doi:10.3847/2041-8205/824/2/L27.
García-Rojas, Jorge, Corradi, Romano L. M., Jones, David, Rodríguez-Gil, Pablo, Cabrera-Lavers, Antonio, and Monteiro, Hektor. 2016. "IMAGING THE ELUSIVE H-POOR GAS IN THE HIGH adf PLANETARY NEBULA NGC 6778". United States. doi:10.3847/2041-8205/824/2/L27.
@article{osti_22654292,
title = {IMAGING THE ELUSIVE H-POOR GAS IN THE HIGH adf PLANETARY NEBULA NGC 6778},
author = {García-Rojas, Jorge and Corradi, Romano L. M. and Jones, David and Rodríguez-Gil, Pablo and Cabrera-Lavers, Antonio and Monteiro, Hektor},
abstractNote = {We present the first direct image of the high-metallicity gas component in a planetary nebula (NGC 6778), taken with the OSIRIS Blue Tunable Filter centered on the O ii λ 4649+50 Å optical recombination lines (ORLs) at the 10.4 m Gran Telescopio Canarias. We show that the emission of these faint O ii ORLs is concentrated in the central parts of the planetary nebula and is not spatially coincident either with emission coming from the bright [O iii] λ 5007 Å collisionally excited line (CEL) or the bright H α recombination line. From monochromatic emission line maps taken with VIMOS at the 8.2 m Very Large Telescope, we find that the spatial distribution of the emission from the auroral [O iii] λ 4363 line resembles that of the O ii ORLs but differs from nebular [O iii] λ 5007 CEL distribution, implying a temperature gradient inside the planetary nebula. The centrally peaked distribution of the O ii emission and the differences with the [O iii] and H i emission profiles are consistent with the presence of an H-poor gas whose origin may be linked to the binarity of the central star. However, determination of the spatial distribution of the ORLs and CELs in other PNe and a comparison of their dynamics are needed to further constrain the geometry and ejection mechanism of the metal-rich (H-poor) component and hence, understand the origin of the abundance discrepancy problem in PNe.},
doi = {10.3847/2041-8205/824/2/L27},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 824,
place = {United States},
year = 2016,
month = 6
}
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