Results 91 to 100 of about 17,877 (291)

Electron Capture in Stellar Interiors.

The Astrophysical Journal, 1964
The reasons why nuclear electron-capture rates in stars depend on temperature and density are discussed, and some astrophysical applications of continuum electron-capture rates are reviewed. The modern theory of nuclear BETA decay is then used to calculate stellar-continuum electroncapture rates for transitions of an arbitrary degree of forbiddenness ...
openaire   +1 more source

A Q‐Learning Algorithm to Solve the Two‐Player Zero‐Sum Game Problem for Nonlinear Systems

International Journal of Adaptive Control and Signal Processing, Volume 39, Issue 3, Page 566-581, March 2025.
A Q‐learning algorithm to solve the two‐player zero‐sum game problem for nonlinear systems. ABSTRACT This paper deals with the two‐player zero‐sum game problem, which is a bounded L2$$ {L}_2 $$‐gain robust control problem. Finding an analytical solution to the complex Hamilton‐Jacobi‐Issacs (HJI) equation is a challenging task.
Afreen Islam, Anthony Siming Chen, Guido Herrmann   +2 more
wiley   +1 more source

Evolution of a Long-lived Deep-seated Main-sequence Magnetic Field during White Dwarf Cooling

The Astrophysical Journal
We study the evolution of white dwarf (WD) magnetic fields that originate from convective-core dynamos during the main sequence. Using stellar evolution and WD cooling models combined with magnetic field diffusion calculations, we demonstrate that a ...
Matias Castro-Tapia, Maria Camisassa, Shu Zhang   +2 more
doaj   +1 more source

Stellar structure and compact objects before 1940: Towards relativistic astrophysics

, 2017
Since the mid-1920s, different strands of research used stars as "physics laboratories" for investigating the nature of matter under extreme densities and pressures, impossible to realize on Earth.
A. Blum, A. Blum, A. Einstein, A. Friedmann, A. Krasinski, A. Sommerfeld, A.B. Migdal, A.G. Cameron, A.G.W. Cameron, A.H. Taub, A.L. Eremeeva, A.R. Sandage, A.S. Eddington, A.S. Eddington, A.S. Eddington, A.S. Eddington, A.S. Eddington, A.S. Eddington, A.S. Eddington, A.S. Eddington, Anonymous, B. Datt, B. Strömgren, B. Strömgren, C. Critchfield, C. Hazard, C.F. von Weizsäcker, C.F. von Weizsäcker, D. Cenadelli, D.G. Yakovlev, D.G. Yakovlev, D.H. Menzel, D.K. Nadyozhin, Department of Physics, Notre Dame University, E. Fermi, E. Fermi, E. Fermi, E. Schucking, E. Thomas, E. Öpik, E.A. Milne, E.A. Milne, E.A. Milne, E.A. Milne, E.A. Milne, E.A. Milne, E.A. Milne, E.A. Milne, E.C. Stoner, E.C. Stoner, E.C. Stoner, E.E. Salpeter, E.E. Salpeter, E.N. Parker, E.P. Hubble, F. Bloch, F. Cernuschi, F. Cernuschi, F. Cernuschi, F. Hoyle, F. Hoyle, F. Hund, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, F. Zwicky, G. Burbidge, G. Burbidge, G. Burbidge, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Gamow, G. Lemaître, G. Lemaître, G. Lemaître, G. Lemaître, G. Lemaître, G. Lemaître, G. Lemaître, G. Sardanashvily, G.E. Gorelik, G.E. Tauber, G.I. Pokrowski, G.M. Volkoff, G.M. Volkoff, H. Bethe, H. Bethe, H. Bethe, H. Bethe, H. Kragh, H. Thirring, H.-Y. Chiu, H.J. Smith, H.J. Walke, H.N. Russell, H.N. Russell, J. Chadwick, J. Ehlers, J. Eisenstaedt, J. Eisenstaedt, J. Frenkel, J. Frenkel, J. Frenkel, J.A. Wheeler, J.B. Holberg, J.B. Holberg, J.B. Oke, J.H. Jeans, J.H. Reynolds, J.L. Friedman, J.L. Greenstein, J.L. Greenstein, J.R. Oppenheimer, J.R. Oppenheimer, J.R. Oppenheimer, K. Grant, K. Hufbauer, K.S. Thorne, L. Bonolis, L. Hoddeson, L. Landau, L. Mestel, L.D. Landau, L.D. Landau, L.D. Landau, L.F. Bates, M. Bronstein, M. Bronstein, M. Bronstein, M. Nauenberg, M. Schmidt, M.S. Vardya, N. Bohr, P.J.E. Peebles, P.L. Kapitza, R. D’E. Atkinson, R. D’E. Atkinson, R. Minkowski, R. Minkowski, R. Peierls, R. Penrose, R.C. Tolman, R.C. Tolman, R.C. Tolman, R.C. Tolman, R.E. Marshak, R.H. Fowler, R.H. Fowler, R.H. Fowler, R.H. Fowler, R.H. Fowler, R.M. Langer, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Chandrasekhar, S. Flügge, S. Suzuki, S.A. Colgate, T. Hamada, T.D. Lee, T.E. Sterne, T.E. Sterne, T.E. Sterne, T.E. Sterne, T.E. Sterne, T.G. Cowling, V. Ambartsumyan, V. Ambartsumyan, V. Ambartsumyan, V. Regener, V.S. Alpher, W. Anderson, W. Anderson, W. Anderson, W. Anderson, W. Anderson, W. Baade, W. Baade, W. Baade, W. Bothe, W. Pauli, W. Pauli, W.J. Luyten, W.S. Adams, W.S. Adams, W.S. Adams, Y. Hagihara, Y.B. Zeldovich, Y.B. Zeldovich, Y.B. Zeldovich   +214 more
core   +1 more source

Energy generation mechanisms in stellar interiors

, 2012
It is well known that in the calculation of thermonuclear reaction rates in dense and cool plasma, the screening effects must be taken into account. The internal structure and evolution of stars can be obtained with the calculations of equation of state of gas structure, opacity and thermonuclear reaction rates.
openaire   +4 more sources

Constraints on stellar interior physics from helioseismology [PDF]

Symposium - International Astronomical Union, 1997
Traditional observations of the properties of stars generally provide tests of only the gross aspects of stellar structure and evolution. The limitation lies in the amount and precision of the available data of relevance to the structure of the stellar interior, i.e., the determination of stellar effective temperatures, surface composition ...
openaire   +3 more sources

A Robust Adaptive One‐Sample‐Ahead Preview Super‐Twisting Sliding Mode Controller

International Journal of Adaptive Control and Signal Processing, EarlyView.
Block Diagram of the Robust Adaptive One‐Sample‐Ahead Preview Super‐Twisting Sliding Mode Controller. ABSTRACT This article introduces a discrete‐time robust adaptive one‐sample‐ahead preview super‐twisting sliding mode controller. A stability analysis of the controller by Lyapunov criteria is developed to demonstrate its robustness in handling both ...
Guilherme Vieira Hollweg, Paulo Jefferson Dias de Oliveira Evald, Shivam Chaturvedi, Hilton Abilio Gründling, Rodrigo Varella Tambara, Wencong Su   +5 more
wiley   +1 more source

A semi-analytic approach to angular momentum transport in stellar radiative interiors

, 2009
We address the problem of angular momentum transport in stellar radiative interiors with a novel semi-analytic spectral technique, using an eigenfunction series expansion, that can be used to derive benchmark solutions in hydromagnetic regimes with very ...
Lanza, A. F., Lanzafame, A. C., Spada, F.   +2 more
core   +1 more source

Physical mechanisms of mixing in stellar interiors [PDF]

Symposium - International Astronomical Union, 1984
The different mechanisms by which mixing can take place in stellar interiors are considered : the classical Rayleigh-Benard instability with penetrative convection and over-shooting, semi-convection, gravitationnal and radiative settling, turbulent mixing.
openaire   +1 more source

Revisiting Stability Criteria in Ball‐Milled High‐Entropy Alloys: Do Hume–Rothery and Thermodynamic Rules Equally Apply?

Advanced Engineering Materials, Volume 27, Issue 6, March 2025.
The stability criteria affecting the formation of high‐entropy alloys, particularly focusing in supersaturated solid solutions produced by mechanical alloying, are analyzed. Criteria based on Hume–Rothery rules are distinguished from those derived from thermodynamic relations. The formers are generally applicable to mechanically alloyed samples.
Javier S. Blázquez, Alejandro F. Manchón‐Gordón, Antonio Vidal‐Crespo, Rafael Caballero‐Flores, Jhon J. Ipus, Clara F. Conde   +5 more
wiley   +1 more source