Observations of High Rotational CO Lines in Post–Asymptotic Giant Branch Stars and Planetary Nebulae

1997 ◽  
Vol 476 (1) ◽  
pp. 319-326 ◽  
Author(s):  
K. Justtanont ◽  
A. G. G. M. Tielens ◽  
C. J. Skinner ◽  
Michael R. Haas
Keyword(s):  
Planetary Nebulae ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Giant Branch Stars

scholarly journals WORKPLANS: Workshop on Planetary Nebula Observations

Galaxies ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 23 ◽  
Author(s):  
Isabel Aleman ◽  
Jeronimo Bernard-Salas ◽  
Joel H. Kastner ◽  
Toshiya Ueta ◽  
Eva Villaver
Keyword(s):  
Observational Data ◽  
Planetary Nebula ◽  
Dust Emission ◽  
Planetary Nebulae ◽  
Research Field ◽  
Theoretical Modeling ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Open Questions ◽  
Giant Branch Stars

This workshop is the second of the WORKPLANS series, which we started in 2016. The main goal of WORKPLANS is to build up a network of planetary nebulae (PNe) experts to address the main open questions in the field of PNe research. The specific aims of the WORKPLANS workshop series are (i) to discuss and prioritize the most important topics to be investigated by the PN community in the following years; (ii) to establish a network of excellent researchers with complementary expertise; (iii) to formulate ambitious observing proposals for the most advanced telescopes and instrumentation presently available (ALMA, SOFIA, VLT, GTC, HST, etc.), addressing those topics; and (iv) to develop strategies for major proposals to future observatories (JWST, ELT, SPICA, Athena, etc.). To achieve these goals, WORKPLANS II brought together experts in all key sub-areas of the PNe research field, namely: analysis and interpretation of PNe observational data; theoretical modeling of gas and dust emission; evolution from Asymptotic Giant Branch stars (PNe progenitors) to PNe; and the instrumentation and technical characteristics of the relevant observatories.

scholarly journals Powering and Shaping Planetary Nebulae: The Physics of Common Envelopes

2015 ◽  
Vol 11 (A29B) ◽  
Author(s):  
Jason Nordhaus ◽  
David S. Spiegel
Keyword(s):  
Planetary Nebula ◽  
Planetary Nebulae ◽  
Asymptotic Giant Branch ◽  
Close Binary ◽  
Observational Constraints ◽  
Asymptotic Giant Branch Stars ◽  
Common Envelope ◽  
Accretion Rates ◽  
Binary Channels ◽  
Giant Branch Stars

AbstractThe diversity of collimated outflows in post-asymptotic-giant-branch stars and their planetary nebula progeny are often explained by a combination of close binary interactions and accretion. The viability of such scenarios can be tested by comparing kinematic outflow data to determine minimum accretion rates necessary to power observed outflows. While many binary channels have been ruled out with this technique, common envelope interactions can accommodate the current observational constraints, are potentially common, lead to a diverse array of planetary-nebula shapes, and naturally produce period gaps for companions to white dwarfs.

scholarly journals Galactic planetary nebulae with precise nebular abundances as a tool to understand the evolution of asymptotic giant branch stars

2016 ◽  
Vol 461 (1) ◽  
pp. 542-551 ◽  
Author(s):  
D. A. García-Hernández ◽  
P. Ventura ◽  
G. Delgado-Inglada ◽  
F. Dell'Agli ◽  
M. Di Criscienzo ◽  
...  
Keyword(s):  
Planetary Nebulae ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Giant Branch Stars

scholarly journals Maser emission during post-AGB evolution

2012 ◽  
Vol 8 (S287) ◽  
pp. 217-224 ◽  
Author(s):  
J.-F. Desmurs
Keyword(s):  
Planetary Nebulae ◽  
Transition Phase ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Circumstellar Envelopes ◽  
Maser Emission ◽  
Giant Branch Stars ◽  
Short Transition

AbstractThis contribution reviews recent observational results concerning astronomical masers toward post-AGB objects with a special attention to water fountain sources and the prototypical source OH 231.8+4.2. These sources represent a short transition phase in the evolution between circumstellar envelopes around asymptotic giant branch stars and planetary nebulae. The main masing species are considered and key results are summarized.

scholarly journals Rapid evolution of [WC] stars in the Magellanic Clouds

2020 ◽  
Vol 642 ◽  
pp. A71
Author(s):  
Marcin Hajduk
Keyword(s):  
South African ◽  
Rapid Evolution ◽  
Planetary Nebulae ◽  
Magellanic Clouds ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Evolutionary Models ◽  
Heating Rates ◽  
Giant Branch Stars ◽  
Central Stars

We obtained new spectra of fourteen Magellanic Cloud planetary nebulae with the South African Large Telescope to determine heating rates of their central stars and to verify evolutionary models of post-asymptotic giant branch stars. We compared new spectra with observations made in previous years. Five planetary nebulae showed an increase in excitation over time. Four of their central stars exhibit [WC] features in their spectra, including three new detections. This raises the total number of [WC] central stars of PNe in the Magellanic Clouds to ten. We compared determined heating rates of the four [WC] central stars with the He-burning post-asymptotic giant branch evolutionary tracks and the remaining star with the H-burning tracks. Determined heating rates are consistent with the evolutionary models for both H and He-burning post-asymptotic giant branch stars. The central stars of the PNe that show the fastest increase of excitation are also the most luminous in the sample. This indicates that [WC] central stars in the Magellanic Clouds evolve faster than H-burning central stars, and they originate from more massive progenitors.

scholarly journals Powering and Shaping Planetary Nebulae: The Physics of Common Envelopes

2015 ◽  
Vol 11 (A29B) ◽  
pp. 33-36
Author(s):  
Jason Nordhaus ◽  
David S. Spiegel
Keyword(s):  
Planetary Nebula ◽  
Planetary Nebulae ◽  
Asymptotic Giant Branch ◽  
Close Binary ◽  
Observational Constraints ◽  
Asymptotic Giant Branch Stars ◽  
Common Envelope ◽  
Accretion Rates ◽  
Binary Channels ◽  
Giant Branch Stars

AbstractThe diversity of collimated outflows in post-asymptotic-giant-branch stars and their planetary nebula progeny are often explained by a combination of close binary interactions and accretion. The viability of such scenarios can be tested by comparing kinematic outflow data to determine minimum accretion rates necessary to power observed outflows. While many binary channels have been ruled out with this technique, common envelope interactions can accommodate the current observational constraints, are potentially common, lead to a diverse array of planetary-nebula shapes, and naturally produce period gaps for companions to white dwarfs.

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