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相关论文: An Updated Formalism For Line-Driven Radiative Acc…

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In this paper, we study the structure and stability of line driven winds using numerical hydrodynamic simulations. We calculate the radiation force from an explicit non-local solution of the radiation transfer equation, rather than a…

天体物理学 · 物理学 2009-11-07 E. L. Gomez , R. J. R. Williams

In a radiatively heated and cooled medium, the thermal instability is a plausible mechanism for forming clouds, while the radiation force provides a natural acceleration, especially when ions recombine and opacity increases. Here we extend…

高能天体物理现象 · 物理学 2015-05-27 Daniel Proga , Tim Waters

Modelling of stellar radiative intensities in various spectral pass-bands plays an important role in stellar physics. At the same time the direct calculations of the high-resolution spectrum and then integrating it over the given spectral…

太阳与恒星天体物理 · 物理学 2021-06-30 L. S. Anusha , A. I. Shapiro , V. Witzke , M. Cernetic , S. K. Solanki , L. Gizon

Radiative pressure exerted by line interactions is a prominent driver of outflows in astrophysical systems, being at work in the outflows emerging from hot stars or from the accretion discs of cataclysmic variables, massive young stars and…

太阳与恒星天体物理 · 物理学 2015-09-29 U. M. Noebauer , S. A. Sim

It has long been observed that the number of weak lines from many-electron atoms follows a power law distribution of intensity. While computer simulations have reproduced this dependence, its origin has not yet been clarified. Here we…

原子物理 · 物理学 2020-05-13 Keisuke Fujii , Julian C. Berengut

Stellar flares are characterized by sudden enhancement of electromagnetic radiation in stellar atmospheres. So far much of our understanding of stellar flares comes from photometric observations, from which plasma motions in flare regions…

太阳与恒星天体物理 · 物理学 2022-04-13 Yuchuan Wu , Hechao Chen , Hui Tian , Liyun Zhang , Jianrong Shi , Han He , Hongpeng Lu , Yu Xu , Haifeng Wang

We review basic physics of line-driven stellar winds of OB stars. We discuss elementary processes due to which stellar winds are accelerated on a microscopic level. We show how these microscopic processes may enable the outflow and how they…

天体物理学 · 物理学 2007-05-23 Jiri Krticka , Jiri Kubat

The Doppler beaming effect, induced by the reflex motion of stars, introduces flux modulations and serves as an efficient method to photometrically determine mass functions for a large number of close binary systems, particularly those…

太阳与恒星天体物理 · 物理学 2024-08-08 Chuanjie Zheng , Yang Huang , Jifeng Liu , Youjun Lu , Henggeng Han , Yuan Tan , Timothy C. Beers

Line intensities and oscillator strengths for the controversial 3C and 3D astrophysically relevant lines in neonlike Fe${}^{16+}$ ions are calculated. We show that, for strong x-ray sources, the modeling of the spectral lines by a peak with…

In disk wind models for active galactic nuclei (AGN) outflows, high-energy radiation poses a significant problem wherein the gas can become overionized, effectively disabling what is often inferred to be the largest force acting on the gas:…

星系天体物理 · 物理学 2024-04-26 Kara Smith , Daniel Proga , Randall Dannen , Sergei Dyda , Tim Waters

Conventionally, friction is understood as an efficient dissipation mechanism depleting a physical system of energy as an unavoidable feature of any realistic device involving moving parts, e.g., in mechanical brakes. In this work, we…

加速器物理 · 物理学 2019-05-07 Z. Gong , F. Mackenroth , X. Q. Yan , A. V. Arefiev

Recent observation of some luminous transient sources with low color temperatures suggests that the emission is dominated by optically thick winds driven by super-Eddington accretion. We present a general analytical theory of the dynamics…

高能天体物理现象 · 物理学 2016-04-01 Rong-Feng Shen , Ehud Nakar , Tsvi Piran

Intermediate mass protostarsprovide a bridge between theories of low- and high-mass star formation. Emerging molecular outflows can be used to determine the influence of fragmentation and multiplicity on protostellar evolution through the…

Calculations of the opacity of hot, dense matter require models for plasma line broadening. However, the most general theories are too complex to calculate directly and some approximation is inevitably required. The most widely-used…

等离子体物理 · 物理学 2020-10-05 R. A. Baggott , S. J. Rose , S. P. D. Mangles

An analysis of ~19500 narrow (<200 km/s) CIV 1548.2,1550.8 absorbers in ~34000 Sloan Digital Sky Survey quasar spectra is presented. The statistics of the number of absorbers as a function of outflow-velocity shows that in approximately…

星系天体物理 · 物理学 2015-06-22 Rebecca A. A. Bowler , Paul C. Hewett , James T. Allen , Gary J. Ferland

Time-dependent numerical studies of line-driven winds using the Sobolev approximation have a history spanning over three decades. In many of these studies, the wind solutions display notorious oscillations. Two clues suggest the…

星系天体物理 · 物理学 2025-04-23 Joshua Key , Daniel Proga , Randall Dannen , Sterling Vivier , Timothy Waters

Hot, massive (OB) stars experience strong line-driven stellar winds and mass loss. As the majority of efficient driving lines are metallic, the amount of wind driving and mass loss is dependent on the stellar metallicity Z. In addition,…

太阳与恒星天体物理 · 物理学 2022-07-13 F. A. Driessen , J. O. Sundqvist , A. Dagore

The frequency shift of spectral lines is most often explained by the Doppler Effect in terms of relative motion, whereas the Doppler broadening of a particular line mainly depends on the absolute temperature. The Wolf effect on the other…

天体物理学 · 物理学 2009-10-31 Sisir Roy , Menas Kafatos , Suman Dutta

The radiative transfer equation for spectral lines from an extended gas is derived from first principles, treating the gas as a system of many atoms/molecules rather than isolated ones. Line broadening effects are assumed to be dominated by…

星系天体物理 · 物理学 2026-01-14 Boy Lankhaar

We review recent developments regarding radiation driven mass loss from OB-stars. We first summarize the fundamental theoretical predictions, and then compare these to observational results (including the VLT-FLAMES survey of massive…

太阳与恒星天体物理 · 物理学 2009-11-05 J. Puls , J. O. Sundqvist , F. Najarro , M. M. Hanson