Results 71 to 80 of about 10,224 (240)

Stellar populations

, 2013
This is a summary of my lectures during the 2011 IAC Winter School in Puerto de la Cruz. I give an introduction to the field of stellar populations in galaxies, and highlight some new results. Since the title of the Winter School was {\it Secular Evolution of Galaxies} I mostly concentrate on nearby galaxies, which are best suited to study this theme ...
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Stellar Prominences [PDF]

Symposium - International Astronomical Union, 1996
I review recent observational and theoretical progress in the study of condensations of cool material trapped in the coronae of rapidly rotating stars. Such condensations were discovered over a decade ago, producing transient moving absorption features in the optical Balmerseries lines.
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Stellar Oscillons

Annals of the New York Academy of Sciences, 1998
ABSTRACT: We study the weakly nonlinear evolution of acoustic instability of a plane‐parallel polytrope with thermal dissipation in the form of Newton's law of cooling. The most unstable horizontal wavenumbers form a band around zero and this permits the development of a nonlinear pattern theory leading to a complex Ginzburg‐Landau equation (CGLE ...
Umurhan, O. M., Tao, L., Spiegel, E. A.
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The level of non-thermal velocity fluctuations deduced from Doppler spectroscopy and its role on TJ-II confinement

, 2009
The goal of this investigation is to study, in the line of previous works, the level of velocity fluctuations in different scenarios of the TJ-II stellarator.
Baciero, Dinklage, Landi, McCarthy, Rapisarda, Rapisarda, Zurro   +6 more
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Stellar atmospheres

This is a pre-print of a chapter for the Encyclopedia of Astrophysics (edited by I. Mandel, section editor F.R.N.
Puls, Joachim, Herrero, Artemio, Prieto, Carlos Allende   +2 more
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Global linear drift-wave eigenmode structures on flux surfaces in stellarators: ion temperature gradient mode

Nuclear Fusion
Turbulent transport greatly impacts the performance of stellarator magnetic confinement devices. While significant progress has been made on the numerical front, theoretical understanding of turbulence in stellarators is still lacking. In particular, due
Hongxuan Zhu, H. Chen, Z. Lin, A. Bhattacharjee   +3 more
doaj   +1 more source

Extension and its characteristics of ECRH plasma in the LHD

, 2004
One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state.
A Komori, A Sagara, Alejaldre C, B J Peterson, Bornatici M, H Funaba, H Idei, H Nakanishi, H Yamada, I Yamada, Iiyoshi A, J Miyazawa, K Ida, K Ikeda, K Itoh, K Kawahata, K Khlopenkov, K Nagaoka, K Narihara, K Nishimura, K Ohkubo, K Saito, K Tanaka, K Toi, K Tsumori, K Watanabe, K Yamazaki, Kubo S, Kubo S, M Emoto, M Goto, M Isobe, M Nishiura, M Osakabe, M Shoji, M Yokoyama, M Yoshinuma, Maassberg H, N Ashikawa, N Noda, N Ohyabu, N Takeuchi, N Tamura, Notake T, O Kaneko, O Motojima, R Kumazawa, R Sakamoto, S Inagaki, S Kubo, S Masuzaki, S Morita, S Murakami, S Muto, S Ohdachi, S Sakakibara, S Sudo, Shimozuma T, Shimozuma T, T Ido, T Kobuchi, T Minami, T Morisaki, T Mutoh, T Notake, T Ozaki, T Seki, T Shimozuma, T Tokuzawa, T Watanabe, T Watari, Y Hamada, Y Nagayama, Y Nakamura, Y Narushima, Y Oka, Y Takeiri, Y Yoshimura, Yokoyama M   +78 more
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The topology of non-resonant stellarator divertors

Nuclear Fusion
We apply topological methods to better understand how the magnetic field in the stellarator edge can be diverted away from the confined region. Our primary method is calculating the winding numbers of closed contours, which gives information on the ...
Robert Davies, Christopher B. Smiet, Alkesh Punjabi, Allen H. Boozer, Sophia A. Henneberg   +4 more
doaj   +1 more source

Microtearing Modes in Reversed Field Pinch Plasmas

, 2010
In the reversed field pinch RFX-mod strong electron temperature gradients develop when the Single-Helical-Axis regime is achieved. Gyrokinetic calculations show that in the region of the strong temperature gradients microtearing instabilities are the ...
Bonfiglio, D., Cappello, S., Predebon, I., Sattin, F., Veranda, M.   +4 more
core   +1 more source

Stellar magnetism

Stellar Magnetism affects all spectral types and exists and varies throughout the evolution of stars. Magnetic fields can affect not only the interior of stars, but also their circumstellar environments. In this chapter, we concentrate on the magnetic fields that can be measured at the surface of stars through the influence of the Zeeman effect on ...
Petit, Veronique, Oksala, Mary E.
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