Results 21 to 30 of about 37,593 (223)

Amorphous alumina in the extended atmosphere of Alpha Orionis [PDF]

, 2005
In this paper we study the extended atmosphere of the late-type supergiant Alpha Orionis. Infrared spectroscopy of red supergiants reveals strong molecular bands, some of which do not originate in the photosphere but in a cooler layer of molecular ...
Aringer, Ayres, B. Vandenbussche, Basri, Begemann, Bester, Bouwman, Chagnon, Chesneau, Cloutman, Danchi, Decin, Feautrier, Fleischer, Freytag, G. Perrin, Gilliland, Goldman, Goorvitch, Gray, Gustafsson, Hanbury Brown, Harper, Höfner, J. Cami, Jennings, K. Eriksson, Knapp, Knapp, Knapp, Koike, L. B. F. M. Waters, L. Decin, Lamb, Lambert, Langhoff, Leinert, Lim, Lodders, Matsuura, Mennesson, Ohnaka, Ohnaka, Onaka, P. Deroo, Partridge, Patzer, Perrin, Perrin, Perrin, Perryman, Plez, Plez, Posch, R. Van Malderen, Richards, Ryde, S. Hony, Salpeter, Sauval, Sedlmayr, Skinner, Skinner, Sloan, Sloan, Speck, Stothers, Sudol, T. Verhoelst, Tsuji, Tsuji, Tsuji, Van Malderen, Weiner, Woitke, Yamamura   +75 more
core   +4 more sources

Diminishing activity of recent solar cycles (22–24) and their impact on geospace

Journal of Space Weather and Space Climate, 2019
This study examines the variation of different energies linked with the Sun and the Earth’s magnetosphere-ionosphere systems for solar cycles (SCs) 22–24 for which the gradual decrease in the solar activity is noticed.
Kakad Bharati, Kakad Amar, Ramesh Durbha Sai, Lakhina Gurbax S.   +3 more
doaj   +1 more source

Mechanisms for MHD Poynting flux generation in simulations of solar photospheric magneto-convection [PDF]

, 2012
We investigate the generation mechanisms of MHD Poynting flux in the magnetised solar photosphere. Using radiative MHD modelling of the solar photosphere with initial magnetic configurations that differ in their field strength and geometry, we show the ...
Bonet, Schüssler, Stein, Steiner, Vögler   +4 more
core   +2 more sources

On the generation of hydrodynamic shocks by mixed beams and occurrence of sunquakes in flares [PDF]

, 2015
Observations of solar flares with sunquakes by space- and ground-based instruments reveal essentially different dynamics of seismic events in different flares.
Zharkov, Sergei, Zharkova, Valentina
core   +1 more source

Magnetic Tornado Properties: A Substantial Contribution to the Solar Coronal Heating via Efficient Energy Transfer

The Astrophysical Journal, 2023
In solving the solar coronal heating problem, it is crucial to comprehend the mechanisms by which energy is conveyed from the photosphere to the corona. Recently, magnetic tornadoes, characterized as coherent, rotating magnetic-field structures extending
Hidetaka Kuniyoshi, Munehito Shoda, Haruhisa Iijima, Takaaki Yokoyama   +3 more
doaj   +1 more source

Global solar photospheric and coronal magnetic field over activity cycles 21–25

Journal of Space Weather and Space Climate
The evolution of the global solar magnetic field from the beginning of cycle 21 (mid-1970s) until the currently-ascending cycle 25 is described using photospheric full-disk and synoptic magnetograms from NSO Kitt Peak Vacuum Telescope (KPVT) 512-channel ...
Petrie Gordon J. D.
doaj   +1 more source

The convection of close red supergiant stars observed with near-infrared interferometry

, 2015
Our team has obtained observations of the photosphere of the two closest red supergiant stars Betelgeuse ($\alpha$ Ori) and Antares ($\alpha$ Sco) using near infrared interferometry.
Aurière, Michel, Chiavassa, Andrea, Kervella, Pierre, Montargès, Miguel, Perrin, Guy   +4 more
core   +2 more sources

Twisted flux tube emergence from the convection zone to the corona

, 2007
3D numerical simulations of a horizontal magnetic flux tube emergence with different twist are carried out in a computational domain spanning the upper layers of the convection zone to the lower corona.
Carlsson M., Dorch S. B. F., Fan Y., Hansteen V. H., Juan Martínez‐Sykora, Mats Carlsson, Moreno-Insertis F., Nordlund, Schussler M., Viggo Hansteen   +9 more
core   +1 more source

Dust in the Photospheric Environment: Unified Cloudy Models of M, L, and T Dwarfs [PDF]

, 2002
We address the problem of how dust forms and how it could be sustained in the static photospheres of cool dwarfs for a long time. In the cool and dense gas, dust forms easily at the condensation temperature, T_cond, and the dust can be in detailed ...
Biemont E., Blackwell D. E., Borysow A., Brett J. M., Brett J. M., Brown L. R., Brown L. R., Delfosse X., Eriksson T. S., Grevesse N., Grevesse N., Hedgecock I. M., Holweger H., Jones H. R. A., Margolis J. S., Mould J., Nakajima T., Ordal M.A., Ossenkopf V., Takashi Tsuji, Tsuji T., Tsuji T., Tsuji T., Tsuji T., Viti S.   +24 more
core   +4 more sources

The photosphere of Pleione [PDF]

Symposium - International Astronomical Union, 1994
In this paper we report results concerning the photospheric Balmer discontinuity of Pleione. They show that after the Be → Be-shell phase transitions, the stellar photosphere keeps its characteristics unchanged.
openaire   +1 more source