Results 31 to 40 of about 440,001 (300)

Spectral classification of stars based on LAMOST spectra

, 2015
In this work, we select the high signal-to-noise ratio spectra of stars from the LAMOST data andmap theirMK classes to the spectral features. The equivalentwidths of the prominent spectral lines, playing the similar role as the multi-color photometry ...
Cui, Wen-Yuan, Deng, Li-Cai, Hou, Yonghui, Liu, Chao, Wan, Jun-Chen, Wang, Yuefei, Yang, Ming, Zhang, Bo, Zhang, Yong   +8 more
core   +1 more source

KMOS view of the Galactic Centre I. Young stars are centrally concentrated [PDF]

, 2015
The Galactic centre hosts a crowded, dense nuclear star cluster with a half-light radius of 4 pc. Most of the stars in the Galactic centre are cool late-type stars, but there are also >100 hot early-type stars in the central parsec of the Milky Way ...
de Zeeuw, P. T., Feldmeier-Krause, A., Hilker, M., Kissler-Patig, M., Kuntschner, H., Lützgendorf, N., Neumayer, N., Schödel, R., Seth, A., Walcher, C. J.   +9 more
core   +3 more sources

Critical Metallicity of Cool Supergiant Formation. I. Effects on Stellar-mass Loss and Feedback

The Astrophysical Journal, 2023
This paper systematically studies the relation between metallicity and mass loss of massive stars. We perform one-dimensional stellar evolution simulations and build a grid of ∼2000 models with initial masses ranging between 11 and 60 M _⊙ and absolute ...
Po-Sheng Ou, Ke-Jung Chen, You-Hua Chu, Sung-Han Tsai   +3 more
doaj   +1 more source

The coupling of a young stellar disc with the molecular torus in the Galactic centre

, 2010
The Galactic centre hosts, according to observations, a number of early-type stars. About one half of those which are orbiting the central supermassive black hole on orbits with projected radii $\gtrsim$ 0.03 pc form a coherently rotating disc ...
Aarseth, Allen, Bartko, Bartko, Christopher, Collin, Cuadra, Do, Eisenhauer, Genzel, Ghez, Ghez, Gillessen, Gillessen, Hobbs, J. Haas, Kozai, L. Šubr, Levin, Lidov, Löckmann, Morbidelli, P. Kroupa, Paumard, Schödel, Yelda, Zhao, Šubr, Šubr   +28 more
core   +1 more source

New Approach to Superflare Energy Determination

The Astrophysical Journal Letters
We present a new method for estimating the total energy radiated by stellar flares in broadband continua, which assumes a constant emitting area but incorporates a time-dependent temperature evolution.
P. Heinzel, R. Falewicz, K. Bicz, P. Preś   +3 more
doaj   +1 more source

On Technetium Abundance in Late-type Stars [PDF]

Symposium - International Astronomical Union, 1988
Technetium abundances in the atmospheres of S- and C-stars are estimated by comparing the synthetic spectra and high dispersion observed spectra for the TcI λ 5924.47 region. It was found that reliable estimates are possible only for the pure S-stars and SC-stars. For the late carbon stars only the upper limit of the Tc abundance can be found.
openaire   +1 more source

Magnetic fields in late-type stars [PDF]

Monthly Notices of the Royal Astronomical Society, 1981
Observations show that magnetic activity in late-type stars is correlated with rotation rates and that there is a discontinuous change in behavior at a critical rotation period. This can be explained as a consequence of a transition from convection in rolls parallel to the rotation axis to normal convection cells as the angular velocity is decreased.
E. Knobloch, R. Rosner, N. O. Weiss
openaire   +1 more source

Evidence for a New Class of Extreme UV Sources

, 1996
Most of the sources detected in the extreme ultraviolet (EUV; 100 Ang to 600 Ang) by the Rosat WFC and EUVE all-sky surveys have been identified with active late-type stars and hot white dwarfs that are near enough to escape absorption by interstellar ...
Maoz, Dan, Ofek, Eran, Shemi, Amotz
core   +1 more source

The HIT Network for Children and Adolescents With CNS Tumors Facilitates Improvements of Diagnostic Assessments, Multimodal Treatments, Individual Counseling, and Research in Germany, Austria, and Switzerland

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background The HIT network was established in 2000 to create a population‐based structure aiming to improve survival rates and reduce late effects for children with central nervous system (CNS) tumors by conducting comprehensive clinical trials.
Stefan Rutkowski, Michael C. Frühwald, Gudrun Fleischhack, Stephan Tippelt, Pablo Hernáiz‐Driever, Olaf Witt, Astrid Gnekow, Christof Kramm, Matthias Eyrich, Johannes E. A. Wolf, Hermann Müller, Carsten Friedrich, Uwe R. Kordes, Denise Obrecht‐Sturm, Petra Ketteler, Barbara von Zezschwitz, Pascal Johann, Dominik Sturm, Karoline Nemes, Stefan Schönberger, Till Milde, Brigitte Bison, Monika Warmuth‐Metz, Torsten Pietsch, Ulrich Schüller, Arend Koch, David Capper, Martin Hasselblatt, Christian Thomas, Christian Hagel, Stefan M. Pfister, Felix Sahm, David T. W. Jones, Martin U. Schuhmann, Jürgen Krauss, Pedram Emami, Ahmed El Damaty, Rolf D. Kortmann, Rudolf Schwarz, Jürgen Debus, Mechthild Krause, Fabian Pohl, Holger Ottensmeier, Lisa Bußenius, Katja Baust, Andreas Faldum, Cecile Ronckers, Desiree Grabow, Martin Benesch, Thomas Perwein, Karin Dieckmann, Irene Slavc, Johannes Gojo, Nicolas U. Gerber, André O. von Bueren, Katrin Scheinemann, Gabriele Calaminus, Beate Timmermann, Ulrich‐Wilhelm Thomale, Martin Mynarek   +59 more
wiley   +1 more source

Differential photometry of EK DRA and 29 DRA [PDF]

Serbian Astronomical Journal, 2005
We report on BVR precise photometry of active late-type stars EK DRA and 29 DRA in the spring of 2004. The analysis suggests a reasonable fit with single spot model for both cases in the season as far as the V-curve is concerned.
Zboril M.
doaj   +1 more source