Infrared Emission from Planetary Nebulae with H-rich and H-poor Central Stars.

1997 ◽  
pp. 229-229
Author(s):  
S. K. Górny ◽  
R. Szczerba ◽  
M. Zalfresso-Jundziłło
1997 ◽  
Vol 180 ◽  
pp. 229-229 ◽  
Author(s):  
S.K. Górny ◽  
R. Szczerba ◽  
M. Zalfresso-Jundziłło

We report on an investigation of the infrared properties of planetary nebulae (PNe) with H-rich central stars and with [WR]-type central stars ([WR] PNe) which certainly are H-poor. The infrared radiation comes mainly from the layers expelled at the AGB and can reveal the evolutionary history of the two groups.


1993 ◽  
Vol 155 ◽  
pp. 480-480
Author(s):  
C.Y. Zhang ◽  
S. Kwok

Making use of the results from recent infrared and radio surveys of planetary nebulae, we have selected 431 nebulae to form a sample where a number of distance-independent parameters (e.g., Tb, Td, I60μm and IRE) can be constructed. In addition, we also made use of other distance-independent parameters ne and T∗ where recent measurements are available. We have investigated the relationships among these parameters in the context of a coupled evolution model of the nebula and the central star. We find that most of the observed data in fact lie within the area covered by the model tracks, therefore lending strong support to the correctness of the model. Most interestingly, we find that the evolutionary tracks for nebulae with central stars of different core masses can be separated in a Tb-T∗ plane. This implies that the core masses and ages of the central stars can be determined completely independent of distance assumptions. The core masses and ages have been obtained for 302 central stars with previously determined central-star temperatures. We find that the mass distribution of the central stars strongly peaks at 0.6 M⊙, with 66% of the sample having masses <0.64 MM⊙. The luminosities of the central stars are then derived from their positions in the HR diagram according to their core masses and central star temperatures. If this method of mass (and luminosity) determination turns out to be accurate, we can bypass the extremely unreliable estimates for distances, and will be able to derive other physical properties of planetary nebulae.


2017 ◽  
Vol 600 ◽  
pp. L9 ◽  
Author(s):  
D. Jones ◽  
H. Van Winckel ◽  
A. Aller ◽  
K. Exter ◽  
O. De Marco

2013 ◽  
Vol 558 ◽  
pp. A122 ◽  
Author(s):  
Jorge García-Rojas ◽  
Miriam Peña ◽  
Christophe Morisset ◽  
Gloria Delgado-Inglada ◽  
Adal Mesa-Delgado ◽  
...  

2016 ◽  
Vol 12 (S323) ◽  
pp. 65-69 ◽  
Author(s):  
Jorge García-Rojas ◽  
Romano L. M. Corradi ◽  
Henri M. J. Boffin ◽  
Hektor Monteiro ◽  
David Jones ◽  
...  

AbstractThe discrepancy between abundances computed using optical recombination lines (ORLs) and collisionally excited lines (CELs) is a major, unresolved problem with significant implications for the determination of chemical abundances throughout the Universe. In planetary nebulae (PNe), the most common explanation for the discrepancy is that two different gas phases coexist: a hot component with standard metallicity, and a much colder plasma enhanced in heavy elements. This dual nature is not predicted by mass loss theories, and direct observational support for it is still weak. In this work, we present our recent findings that demonstrate that the largest abundance discrepancies are associated with close binary central stars. OSIRIS-GTC tunable filter imaging of the faint O ii ORLs and MUSE-VLT deep 2D spectrophotometry confirm that O ii ORL emission is more centrally concentrated than that of [Oiii] CELs and, therefore, that the abundance discrepancy may be closely linked to binary evolution.


2016 ◽  
Vol 152 (2) ◽  
pp. 34 ◽  
Author(s):  
Todd C. Hillwig ◽  
Howard E. Bond ◽  
David J. Frew ◽  
S. C. Schaub ◽  
Eva H. L. Bodman

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