Results 21 to 30 of about 270 (136)

Post-AGB stars in the LMC and SMC [PDF]

Proceedings of the International Astronomical Union, 2011
AbstractGalactic post-AGB stars show a large diversity in chemical compositions as well as in the kinematical and geometrical properties of their circumstellar material. The theoretical interpretation is hampered by the lack of good distances to almost all Galactic objects.
Hans Van Winckel, Els van Aarle, Peter R. Wood, Devika Kamath, Tom Lloyd Evans, Kenneth De Smedt, Nadya Gorlova, Clio Gielen   +7 more
openaire   +1 more source

Magnetic fields of AGB and post-AGB stars [PDF]

Proceedings of the International Astronomical Union, 2018
AbstractThere is ample evidence for the presence of strong magnetic fields in the envelopes of (post-)Asymptotic Giant Branch (AGB) stars as well as supergiant stars. The origin and role of these fields are still unclear. This paper updates the current status of magnetic field observations around AGB and post-AGB stars, and describes their possible ...
openaire   +2 more sources

The Chemical Composition of Post AGB Stars [PDF]

Symposium - International Astronomical Union, 1993
The F-type supergiant HD 56126 (F5I) is an IRAS source with detached cold dust shell with characteristics similar to the dust shells around planetary nebulae. From an analysis of high resolution and high signal to noise ratio spectra metal and CNO abundances have been determined. It is found that in HD 56126 [C/H] =−0.01, [N/H]=+0.17, [O/H] = −0.02, [S/
M. Parthasarathy, P. Garcia Lario, S. R. Pottasch   +2 more
openaire   +1 more source

The Circumstellar Envelopes of Post-AGB Stars [PDF]

Proceedings of the International Astronomical Union, 2006
Mid-IR images of a small sample of post-AGB stars have been obtained with the mid-IR camera, OSCIR, mounted on the 8-m Gemini North Telescope. Model calculations, using a 2-D dust RT code, have been performed in order to constrain the physical and chemical properties of the dust in the envelopes, for each object.
Kim L. Clube, Tim M. Gledhill
openaire   +1 more source

Possible Post-AGB Stars

, 2003
Radial velocities were measured for 5 potential post-AGB stars, two in the globular cluster NGC 1851 and three in the dSph galaxy Ursa Minor. All five potential PAGB stars were found to be radial velocity non-members.
Wallerstein, G., Gonzalez, G., Shetrone, M. D.   +2 more
openaire   +2 more sources

Disturbance from restoration reseeding is associated with short‐term topsoil carbon loss and alters soil bacterial communities and functions in degraded alpine meadows of the Qinghai–Xizang Plateau

Grassland Research, EarlyView.
Restoration reseeding of degraded alpine meadows increased aboveground vegetation but was associated with short‐term topsoil carbon loss, coinciding with a microbial strategy shift from resident carbon‐preserving to carbon‐spending bacterial guilds. Abstract Background Restoration of degraded ecosystems is widely promoted as a nature‐based solution ...
Long‐Tao Zhu, Wen‐Min Shi, Guang‐Peng Qu, Xu Yin, Yong‐Kang Zhang, Ying‐Jie Sun, Zhen Luo, Wei Li, Chun‐Ping Zhang, Jie‐Jun Xi   +9 more
wiley   +1 more source

Morphological classification of post-AGB stars [PDF]

Proceedings of the International Astronomical Union, 2011
AbstractWe present a complete study of the morphology of post-Asymptotic Giant Branch (post-AGB) stars. The post-AGB stage is a very short evolutionary phase between the end of the AGB and the beginning of the Planetary Nebula (PN) stage (between 100 and 10,000 yrs).
Manchado, A., Garcia-Hernandez, D. A., Villaver, E., de Massas, J. Guironnet   +3 more
openaire   +2 more sources

Plant Trait‐ and Soil‐Mediated Responses of Herbaceous Aboveground Biomass Across Community Types Along a Degradation Gradient in the Desert Steppe

Land Degradation &Development, EarlyView.
ABSTRACT Grassland degradation profoundly alters the structure and function of desert steppe ecosystems. However, the responses of herbaceous aboveground biomass (Herb‐AGB) to degradation across different plant community types and the underlying mechanisms remain poorly understood.
Huaihai Wang, Zhaobin Song, Ya Hu, Ping Yue, Jingjuan Qiao, Xiaoxue Zhang, Zhengjiaoyi Wang, Fangwei Hao, Xiaoan Zuo   +8 more
wiley   +1 more source

Application of Circular Economy Principles to Power Generation: Extending the Life of A Hydropower Plant by Pumped Hydro Energy Storage

Sustainable Development, EarlyView.
ABSTRACT The application of circular economy, which aims to maximize efficiency and reduce waste, to renewable energy sources necessitates, given the intermittent nature of the latter, robust energy storage solutions to ensure grid stability and avoid wasting energy.
Ó. Martín‐Llorente, E. Jiménez‐Macias, J. C. Sáenz‐Diez Muro, E. Martínez‐Cámara, J. Blanco‐Fernández   +4 more
wiley   +1 more source

RELICS OF ANCIENT POST-AGB STARS IN A PRIMITIVE METEORITE [PDF]

The Astrophysical Journal, 2013
Graphite is one of the many presolar circumstellar condensate species found in primitive meteorites. While the isotopic compositions of low-density graphite grains indicate an origin in core-collapse supernovae, some high-density grains have extreme isotopic anomalies in C, Ca and Ti, which cannot be explained by envelope predictions of asymptotic ...
Jadhav, M., Pignatari, M., Herwig, F., Zinner, E., Gallino, R., Huss, G. R.   +5 more
openaire   +4 more sources