N
Nikolai V. Erkaev
Researcher at Siberian Federal University
Publications - 200
Citations - 5498
Nikolai V. Erkaev is an academic researcher from Siberian Federal University. The author has contributed to research in topics: Magnetohydrodynamics & Solar wind. The author has an hindex of 38, co-authored 197 publications receiving 4872 citations. Previous affiliations of Nikolai V. Erkaev include Saint Petersburg State University & Russian Academy of Sciences.
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Journal ArticleDOI
Roche lobe effects on the atmospheric loss from "Hot Jupiters"
Nikolai V. Erkaev,Yu. N. Kulikov,Helmut Lammer,Franck Selsis,D. Langmayr,G. F. Jaritz,Helfried K. Biernat,Helfried K. Biernat +7 more
TL;DR: In this article, the effect of the Roche lobe on the atmospheric loss from short-periodic gas giants was investigated and reasonably accurate approximate formulas to estimate atmospheric loss enhancement due to the action of tidal forces on a hot Jupiter and to calculate the critical temperature for the onset of geometrical blow-off.
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Coronal mass ejection (CME) activity of low mass M stars as an important factor for the habitability of terrestrial exoplanets. II. CME-induced ion pick up of Earth-like exoplanets in close-in habitable zones.
Helmut Lammer,Herbert Lichtenegger,Yuri N. Kulikov,J.-M. Grießmeier,Naoki Terada,Nikolai V. Erkaev,Helfried K. Biernat,Helfried K. Biernat,Maxim L. Khodachenko,Ignasi Ribas,Thomas Penz,Thomas Penz,Franck Selsis +12 more
TL;DR: It is suggested that larger and more massive terrestrial-type exoplanets may better protect their atmospheres against CMEs, because the larger cores of such exoplanet would generate stronger magnetic moments and their higher gravitational acceleration would constrain the expansion of their thermosphere-exosphere regions and reduce atmospheric escape.
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Determining the mass loss limit for close-in exoplanets: what can we learn from transit observations?
Helmut Lammer,Petra Odert,Martin Leitzinger,Maxim L. Khodachenko,Mykhaylo Panchenko,Yu. N. Kulikov,T. L. Zhang,Herbert Lichtenegger,Nikolai V. Erkaev,Günther Wuchterl,Giuseppina Micela,T. Penz,Helfried K. Biernat,J. Weingrill,M. Steller,H. Ottacher,J. Hasiba,Arnold Hanslmeier +17 more
TL;DR: In this paper, the authors estimate the position of the pressure balance boundary between Coronal Mass Ejection (CME) and stellar wind ram pressures and the planetary ionosphere pressure for non- or weakly magnetized gas giants at close orbits.
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Origin and loss of nebula-captured hydrogen envelopes from ‘sub’- to ‘super-Earths’ in the habitable zone of Sun-like stars
Helmut Lammer,Alexander Stökl,Nikolai V. Erkaev,Nikolai V. Erkaev,Ernst A. Dorfi,Petra Odert,Petra Odert,Manuel Güdel,Yu. N. Kulikov,Kristina G. Kislyakova,Martin Leitzinger +10 more
TL;DR: In this paper, the authors investigated the origin and loss of captured hydrogen envelopes from protoplanets having masses in a range between sub-Earth-like bodies of 0.1 M and super-Earths with 5 M in the habitable zone at 1 au of a Sun-like G star.
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Probing the blow-off criteria of hydrogen-rich 'super-Earths'
Helmut Lammer,Nikolai V. Erkaev,Nikolai V. Erkaev,Petra Odert,Petra Odert,Kristina G. Kislyakova,Kristina G. Kislyakova,Martin Leitzinger,Maxim L. Khodachenko +8 more
TL;DR: In this article, a time-dependent numerical algorithm was applied to solve the system of 1-D fluid equations for mass, momentum, and energy conservation to investigate the criteria under which super-Earths with hydrogen-dominated upper atmospheres can experience hydrodynamic expansion by heating of the stellar XUV (soft X-rays and extreme ultraviolet) radiation and thermal escape via blow-off.