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相关论文: Lya Polarisation in Thick H I Media

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The Lya line transfer in an extremely thick medium of neutral hydrogen is investigated by adopting an accelerating scheme in our Monte Carlo code to skip a large number of core or resonant scatterings. This scheme reduces computing time…

天体物理学 · 物理学 2009-11-07 Sang-Hyeon Ahn , Hee-Won Lee , Hyung Mok Lee

The high-redshift Universe contains luminous Lyman Alpha (hereafter Lya) emitting sources such as galaxies and quasars. The emitted Lya radiation is often scattered by surrounding neutral hydrogen atoms. We show that the scattered Lya…

天体物理学 · 物理学 2009-11-13 Mark Dijkstra , Abraham Loeb

The unification scheme of active galactic nuclei (AGNs) invokes an optically thick molecular torus component hiding the broad emission line region. Assuming the presence of a thick neutral component in the molecular torus characterized by a…

星系天体物理 · 物理学 2016-12-22 Seok-Jun Chang , Hee-Won Lee , Yujin Yang

Lyman-$\alpha$ (Ly$\alpha$) is a powerful astrophysical probe. Not only is it ubiquitous at high redshifts, it is also a resonant line, making Ly$\alpha$ photons scatter. This scattering process depends on the physical conditions of the gas…

星系天体物理 · 物理学 2018-04-05 Marius B. Eide , Max Gronke , Mark Dijkstra , Matthew Hayes

A line photon incident in an electron-scattering medium is transferred in a diffusive way both in real space and in frequency space, and the mean number of scatterings changes as the wavelength shifts from the line center. This leads to the…

天体物理学 · 物理学 2009-10-31 Hee-Won Lee

We present Monte Carlo calculations of Lyman alpha (Lya) radiative transfer through collapsing gas clouds, representing proto-galaxies that are caught in the process of their assembly. Such galaxies produce Lya flux over an extended solid…

天体物理学 · 物理学 2008-11-26 Mark Dijkstra , Zoltan Haiman , Marco Spaans

We compute the polarization of the Lyman alpha line photons emerging from an anisotropically expanding and optically thick medium, which is expected to operate in many Lyman alpha emitting objects including the primeval galaxy DLA~2233+131…

天体物理学 · 物理学 2009-10-30 Hee-Won Lee , Sang-Hyeon Ahn

As a result of resonant scatterings off hydrogen atoms, Lyman-alpha (Lya) emission from star-forming galaxies provides a probe of the (hardly isotropic) neutral gas environment around them. We study the effect of the environmental…

宇宙学与河外天体物理 · 物理学 2015-06-16 Zheng Zheng , Joshua Wallace

In Loeb & Rybicki (1999; paper I) it was shown that before reionization, the scattering of \lya photons from a cosmological source might lead to a fairly compact ($\sim 15''$) \lya halo around the source. Observations of such halos could…

天体物理学 · 物理学 2009-10-31 George B. Rybicki , Abraham Loeb

We combine a cosmological reionization simulation with box size of 100Mpc/h on a side and a Monte Carlo Lyman-alpha (Lya) radiative transfer code to model Lyman Alpha Emitters (LAEs) at z~5.7. The model introduces Lya radiative transfer as…

宇宙学与河外天体物理 · 物理学 2014-11-20 Zheng Zheng , Renyue Cen , Hy Trac , Jordi Miralda-Escude

Lya nebulae, or "Lya blobs", are extended (up to ~100 kpc), bright (L[Lya] > 10^43 erg/s) clouds of Lya emitting gas that tend to lie in overdense regions at z ~ 2--5. The origin of the Lya emission remains unknown, but recent theoretical…

We present constrained radiative transfer calculations of Lyman Alpha (Lya) photons propagating through clumpy, dusty, large scale outflows, and explore whether we can quantitatively explain the Lya halos that have been observed around…

宇宙学与河外天体物理 · 物理学 2015-06-04 Mark Dijkstra , Roban Hultman Kramer

In many symbiotic stars there appear broad wings around H alpha, of which the formation mechanism proposed thus far includes a fast outflow, the inner accretion disc motion, electron scattering and Raman scattering of Ly beta. We adopt a…

天体物理学 · 物理学 2009-11-07 Jerry Jaiyul Yoo , Jih-Yong Bak , Hee-Won Lee

Ly-alpha emitting galaxies and giant Ly-alpha blobs (LABs) have been extensively observed to study the formation history of galaxies. However, the origin of their extended Ly-alpha emission, especially of LABs, remains controversial.…

星系天体物理 · 物理学 2022-02-23 Kwang-Il Seon , Hyunmi Song , Seok-Jun Chang

Lyman-alpha (Lya) photons that escape the interstellar medium of star-forming galaxies may be resonantly scattered by neutral hydrogen atoms in the circumgalactic and intergalactic media, thereby increasing the angular extent of the…

宇宙学与河外天体物理 · 物理学 2015-05-20 Zheng Zheng , Renyue Cen , David Weinberg , Hy Trac , Jordi Miralda-Escude

We model the spectra and surface brightness distributions for the Lyman alpha (Lya) radiation expected from protogalaxies that are caught in the early stages of their assembly. We use the results of a companion paper to characterize the…

天体物理学 · 物理学 2008-11-26 Mark Dijkstra , Zoltan Haiman , Marco Spaans

We demonstrate how the stellar and nebular conditions in star-forming galaxies modulate the emission and spectral profile of HI Lya emission line. We examine the net Lya output, kinematics, and in particular emission of blue-shifted Lya…

星系天体物理 · 物理学 2023-02-22 Matthew J. Hayes , Axel Runnholm , Claudia Scarlata , Max Gronke , T. Emil Rivera-Thorsen

Lyman-$\alpha$ nebulae are usually found in massive environments at high redshift ($z > 2$). The origin of their Lyman-$\alpha$ (Lya) emission remains debated. Recent polarimetric observations showed that at least some Lya sources are…

星系天体物理 · 物理学 2016-10-05 M. Trebitsch , A. Verhamme , J. Blaizot , J. Rosdahl

We report the observation of a further asymmetric, extended Lyman alpha emitting halo at z=2.63, from our ultra-deep, long-slit spectroscopic survey of faint high redshift emitters, undertaken with Magellan LDSS3 in the GOODS-S field. The…

宇宙学与河外天体物理 · 物理学 2015-06-05 Michael Rauch , George D. Becker , Martin G. Haehnelt , Jean-Rene Gauthier , Wallace L. W. Sargent

Hydrogen Ly-alpha is our primary emission-line window into high redshift galaxies. Surprisingly, despite an extensive literature, Ly-alpha radiative transfer in the most realistic case of a dusty, multi-phase medium has not received…

天体物理学 · 物理学 2009-11-13 Matthew Hansen , S. Peng Oh
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