Results 61 to 70 of about 249 (184)

On a stellar structure for a stellar manifold

, 2002
It is well known that a compact two dimensional surface is homeomorphic to a polygon with the edges identified in pairs. This paper not only presents a new proof of this statement but also generalizes it for any connected n-dimensional stellar manifold with a finite number of vertices.
openaire   +2 more sources

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

Direct construction of low-aspect-ratio advanced stellarators via asymptotic expansion

Nuclear Fusion
Advanced stellarators are promising candidates for fusion reactors due to their intrinsic steady-state operation capability and excellent plasma confinement properties.
Ke Liu, Zhexuan Zheng, Jianlin Peng, Caoxiang Zhu   +3 more
doaj   +1 more source

Stellar Chromospheres [PDF]

International Astronomical Union Colloquium, 1980
Important progress in our understanding of stellar chromospheres has occurred in the past few years as a result of new observations, developments in spectral line formation theory, and the application of that theory to the construction of detailed model chromospheres.
openaire   +1 more source

Quasi-single-stage optimization for permanent magnet stellarators

Nuclear Fusion
Advanced stellarators are typically optimized in two stages. The plasma equilibrium is optimized first, followed by the design of coils/permanent magnets.
Guodong Yu, Ke Liu, Tianyi Qian, Yidong Xie, Xianyi Nie, Caoxiang Zhu   +5 more
doaj   +1 more source

FOCUS-HTS: a new stellarator coil design code for three-dimensional high-temperature superconducting magnets

Nuclear Fusion
Stellarators mainly utilize magnetic fields from external coils to confine the plasma, enabling steady-state operation while avoiding instabilities like disruptions raised from plasma currents.
Xianyi Nie, Jianlin Peng, Yidong Xie, Guodong Yu, Ke Liu, Caoxiang Zhu   +5 more
doaj   +1 more source

Existence of weakly quasisymmetric magnetic fields without rotational transform in asymmetric toroidal domains. [PDF]

Sci Rep, 2022
Sato N.
europepmc   +1 more source

Density profiles in stellarators: an overview of particle transport, fuelling and profile shaping studies at TJ-II

Nuclear Fusion
We provide an overview of activities carried out at the TJ-II stellarator for improving our understanding of- and developing plasma physics models for particle density profiles in stellarators.
J.A. Alonso, D. Alegre, J. Alonso, R. Antón, A. Arias-Camisón, E. Ascasíbar, A. Baciero, J.M. Barcala, M. Barnes, E. Blanco, L. Bueno, A. Bustos, S. Cabrera, E. de la Cal, I. Calvo, A. Cappa, D. Carralero, R. Carrasco, B. Carreras, R. Castro, A. de Castro, L. Cebrián, M. Chamorro, A.A. Chmyga, P. Colino, J. Duque, F.J. Escoto, T. Estrada, A. Fernández, J. Fraguas, J.M. Fontdecaba, A. Gabriel, L. García, I. García-Cortés, R. García-Gómez, J.M. García-Regaña, G. Godino-Sedano, J. Gómez-Manchón, A. González, A. González-Jerez, V. Guisse, J. Hernández-Sánchez, J. Hernanz, C. Hidalgo, P. Ivanova, A. Jiménez-Denche, D. Jiménez-Rey, G. Kocsis, M. Koepke, A.S. Kozachek, F. Lapayese, M. Liniers, D. López, D. López-Bruna, B. López-Miranda, E. de la Luna, E. Maragkoudakis, F. Martín-Díaz, G. Martín-Gómez, J. Martínez-Fernández, K.J. McCarthy, F. Medina, D. Medina-Roque, M. Medrano, P. Méndez, F.J. Miguel, B. van Milligen, A. Molinero, G. Motojima, S. Mulas, M. Navarro, I. Nedzelskiy, R. Nuñez, M. Ochando, E. Oyarzábal, J.L. de Pablos, F. Palomares, N. Panadero, F.I. Parra, C. Pastor, I. Pastor, A. de la Peña, R. Peralta, A. Pereira, P. Pons-Villalonga, A.B. Portas, E. Poveda, F.J. Ramos, G.A. Rattá, M. Redondo, C. Reynoso, E. Rincón, J. de la Riva, C. Rodríguez-Fernández, A. Ros, E. Sánchez, J. Sánchez, E. Sánchez-Sarabia, J.A. Sebastián, E.R. Solano, A. Soleto, T. Szepesi, F.L. Tabarés, D. Tafalla, H. Takahashi, N. Tamura, H. Thienpondt, A. Tolkachev, V. Tribaldos, R. Unamuno, J. Varela, J. Vega, J.L. Velasco, I. Voldiner   +113 more
doaj   +1 more source

Nonlinear saturation of ballooning modes in stellarators

Nuclear Fusion
Ballooning mode saturation is investigated in realistic stellarator configurations using the flux tube approach of Ham et al (2018 Plasma Phys. Control. Fusion 60 075017), Ham et al (2016 Phys. Rev. Lett. 116 235001). The method is adapted to account for
X. Chu, S.C. Cowley, N. Ferraro, Y. Zhou, F.I. Parra   +4 more
doaj   +1 more source

Stellar ages and stellar rotation

, 2016
Stellar ages will play a big role in the next generation of astronomy. Useful to exoplaneteers and galactic archaeologists alike, this relatively under-exploited stellar property is currently limited by the precision of dating techniques. The work presented in this thesis contributes incrementally to a greater understanding of rotation period decay in ...
openaire   +2 more sources