Zobrazeno 1 - 10
of 20
pro vyhledávání: '"Hans Nieuwenhuijzen"'
In an earlier paper De Jager et al. (2018) studied the relation between the intensity variations of the variable equatorial and polar solar magnetic energy sources and that of the average terrestrial northern hemisphere ground temperature. It was fou
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5262f533f6f3457b4802ad5ecb589c0e
https://doi.org/10.21203/rs.3.rs-51876/v1
https://doi.org/10.21203/rs.3.rs-51876/v1
Autor:
Hans Nieuwenhuijzen, C. de Jager
Publikováno v:
Natural Science. :1112-1120
We study the influence of solar activity on climate by investigating the relation between the long-term components of the total magnetic fluxes of both the equatorial and polar fields of the sun and the average terrestrial ground temperature. This is
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::626d32d2cee529d5a3da4f6016406385
https://doi.org/10.4236/ns.2013.510136
https://doi.org/10.4236/ns.2013.510136
We summarize the major aspects of the remarkable, fairly long lasting period ( $\sim 2005$ to $\sim 2010$ ) of low solar activity, that we will call the Transition. It is the transitional stage between the Grand Maximum of the 20th century and a fort
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5b702bcd6fed80bf624f9d9dd9ff521f
https://www.vliz.be/imisdocs/publications/33/297233.pdf
https://www.vliz.be/imisdocs/publications/33/297233.pdf
Autor:
F. A. Musaev, Robert P. Stefanik, Andrea K. Dupree, Guillermo Torres, I. V. Ilyin, Hans Nieuwenhuijzen, C. de Jager, Nancy D. Morrison, G. Israelian, A. Lobel
Publikováno v:
The Astrophysical Journal. 583:923-954
We present an overview of the spectral variability of the peculiar F-type hypergiant Rho Cas, obtained from our long-term monitoring campaigns over the past 8.5 years with four spectrographs in the northern hemisphere. Between 2000 June and September
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::494934191dfcf403daef281e09027725
https://doi.org/10.1086/345503
https://doi.org/10.1086/345503
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 327:452-458
The following instability regions for blueward evolving supergiants are outlined and compared: (1) Areas in the Hertzsprung-Russell(HR) diagram where stars are dynamically unstable. (2) Areas where the effective acceleration in the upper part of the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9ec21b7c4f8100c2e483e78d62f48d82
https://doi.org/10.1046/j.1365-8711.2001.04791.x
https://doi.org/10.1046/j.1365-8711.2001.04791.x
Publikováno v:
EAS Publications Series. :279-280
We present a comparative study of the detailed spectroscopic variability of selected Fe i absorption lines observed between 1991 and 1995 in the optical spectra of the bright yellow hypergiants HR 5171A and Rho Cas. We also compare with the high-reso
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::66cd6986de49583449ba36bfa2025c23
https://doi.org/10.1051/eas/1571062
https://doi.org/10.1051/eas/1571062
Autor:
Cornelis de Jager, Hans Nieuwenhuijzen
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 290:L50-L54
During their evolution, massive stars first swell and thus become red supergiants, after which they shrink again to evolve to the blue supergiant phase. When, during this blueward loop, the effective photospheric temperature Tefl. has increased to va
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9924dd985c18105dce91b2e0ea885824
https://doi.org/10.1093/mnras/290.3.l50
https://doi.org/10.1093/mnras/290.3.l50
Autor:
E. Zsoldos, Hans Nieuwenhuijzen, Garik Israelian, C. de Jager, André Maeder, I. Kolka, Alex Lobel, Georges Meynet
Publikováno v:
\aap
Context. We study the time history of the yellow hypergiant HR 8752 based on high-resolution spectra (1973-2005), the observed MK spectral classification data, B - V- and V-observations (1918-1996) and yet earlier V-observations (1840-1918).Aims. Our
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b05a907b976ea29a8784b673b55c62a5
http://www.vliz.be/imisdocs/publications/72/262672.pdf
http://www.vliz.be/imisdocs/publications/72/262672.pdf
Autor:
Cornelis de Jager, Hans Nieuwenhuijzen
Publikováno v:
International Astronomical Union Colloquium. 108:102-113
A review is given of rate of mass-loss values in the upper part of the Hertzsprung-Russell diagram. Near the luminosity limit of stellar existance = −10−4 M⊙ yr−1. Episodical mass loss in bright variable super- and hypergiants does not signif
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8dfdf4daca174ee75c5a76999a560d30
https://doi.org/10.1017/s0252921100093568
https://doi.org/10.1017/s0252921100093568
Publikováno v:
International Astronomical Union Colloquium. 113:211-220
A review is given of data and theories on the motion fields in super and hypergiants with special reference to LBV’s. We show that the radiative momentum flux is incapable of driving the episodical bursts of mass loss of these stars, and that there
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::eaa23bfdcd71a0da5d4d02d9225d86d0
https://doi.org/10.1017/s0252921100004474
https://doi.org/10.1017/s0252921100004474