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Related papers: Identifying Lyman Alpha Emitters powered by AGNs

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We present the results of a search for Lyman-alpha emission galaxies at z~ 5.7 in the FORS Deep Field. The objective of this study is to improve the faint end of the luminosity function of high-redshift Lyman-alpha emitting galaxies and to…

Astrophysics · Physics 2009-11-11 C. Tapken , I. Appenzeller , A. Gabasch , J. Heidt , U. Hopp , R. Bender , D. Mehlert , S. Noll , S. Seitz , W. Seifert

We report the discovery of Lyman-alpha emission (Ly$\alpha$) in the bright galaxy EGSY-2008532660 (hereafter EGSY8p7) using the MOSFIRE spectrograph at the Keck Observatory. First reported by Roberts-Borsani et al. (2015), it was selected…

We calculate the impact of the intergalactic medium (IGM) on the observed Lyman alpha lines (hereafter Lya) emitted by galaxies in an ionised IGM at z>4. Our model accounts for gas clumping in the IGM and for the fact that high-redshift…

Astrophysics · Physics 2008-11-26 Mark Dijkstra , Adam Lidz , Stuart Wyithe

The intrinsic strength of the Ly$\alpha$ line in young, star-forming systems makes it a special tool for studying high-redshift galaxies. However, interpreting observations remains challenging due to the complex radiative transfer involved.…

Astrophysics of Galaxies · Physics 2019-06-05 Christoph Behrens , Andrea Pallottini , Andrea Ferrara , Simona Gallerani , Livia Vallini

Context. Lyman Break Galaxies (LBG) and Narrow Band (NB) surveys have been successful at detecting large samples of high-redshift galaxies. Both methods are subject to contamination from low-redshift interlopers. Aims. In this paper, our…

We built a grid of photoionization models and compiled already available observational emission line intensities ($\rm 1000 \: < \: \lambda(\AA) \: < \: 2000$) of confirmed star formation regions and Active Galactic Nucleus (AGNs) in order…

Astrophysics of Galaxies · Physics 2018-07-11 O. L. Dors , B. Agarwal , G. F. Hagele , M. V. Cardaci , C. -E. Rydberg , R. A. Riffel , A. S. Oliveira , A. C. Krabbe

Active Galactic Nuclei are considered as possible sites of cosmic ray acceleration and some of them have been observed as high energy gamma ray emitters (Blazars). There naturally comes an appealing idea that the acceleration of the highest…

Astrophysics · Physics 2010-12-03 G. Henri , G. Pelletier , P. O. Petrucci , N. Renaud

The cosmic ionizing emissivity from star-forming galaxies has long been anchored to UV luminosity functions. Here we introduce an emissivity framework based on Ly$\alpha$ emitters (LAEs), which naturally hones in on the subset of galaxies…

We present a structural study of 182 obscured Active Galactic Nuclei (AGNs) at z<=1.5, selected in the COSMOS field from their extreme infrared to X-ray luminosity ratio and their negligible emission at optical wavelengths. We fit optical…

While the Lyman-$\alpha$ ($\mathrm{Ly}\alpha$) emission line serves as an important tool in the study of galaxies at $z\lesssim 6$, finding Ly$\alpha$ emitters (LAE) at significantly higher redshifts has been more challenging, probably…

The Lya emission has been observed from galaxies over a redshift span z ~ 0 - 8.6. However, the evolution of high-redshift Lya emitters (LAEs), and the link between these populations and local galaxies, remain poorly understood. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Hidenobu Yajima , Yuexing Li , Qirong Zhu , Tom Abel , Caryl Gronwall , Robin Ciardullo

We investigate the physical properties of Lyman-alpha emitters (LAEs) and non-Lyman-alpha emitters (non-LAEs) at z$\sim$4.8--9.6 via a stacking analysis of 253 JWST/NIRSpec spectra of galaxies observed as part of the JWST Advanced Deep…

Using new Keck DEIMOS spectroscopy, we examine the origin of the steep number counts of ultra-faint emission-line galaxies recently reported by Dressler et al. (2011). We confirm six Lyman Alpha emitters (LAEs), three of which have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Alaina Henry , Crystal Martin , Alan Dressler , Marcin Sawicki , Patrick McCarthy

Reionization-era galaxies tend to exhibit weak Ly$\alpha$ emission, likely reflecting attenuation from an increasingly neutral IGM. Recent observations have begun to reveal exceptions to this picture, with strong Ly$\alpha$ emission now…

We propose a new model for the extended Ly alpha blobs found recently at high redshift z ~ 3. The observational properties of these blobs are; 1) the observed Ly alpha luminosities are ~ 10^{43} h^{-2} ergs s^{-1}, 2) they appear elongated…

Astrophysics · Physics 2009-10-31 Yoshiaki Taniguchi , Yasuhiro Shioya

We describe narrowband and spectroscopic searches for emission-line star forming galaxies in the redshift range 3 to 6 with the 10 m Keck II Telescope. These searches yield a substantial population of objects with only a single strong…

Astrophysics · Physics 2009-10-30 Esther M. Hu , Lennox L. Cowie , Richard G. McMahon

The JADES survey recently reported the discovery of JADES-GS-z13-1-LA at $z = 13$, the highest redshift Ly$\alpha$ emitter (LAE) ever observed. This observation suggests that either the intergalactic medium (IGM) surrounding…

Astrophysics of Galaxies · Physics 2026-03-30 Joshua Cohon , Christopher Cain , Rogier Windhorst , Anson D'Aloisio , Timothy Carleton , Yongda Zhu

Lyman-Alpha Emitting galaxies (LAEs) are typically young, low-mass, star-forming galaxies with little extinction from interstellar dust. Their low dust attenuation allows their Ly$\alpha$ emission to shine brightly in spectroscopic and…

Ly$\alpha$ photons scattered by neutral hydrogen atoms in the circumgalactic media or produced in the halos of star-forming galaxies are expected to lead to extended Ly$\alpha$ emission around galaxies. Such low surface brightness…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Ethan Lake , Zheng Zheng , Renyue Cen , Raphael Sadoun , Rieko Momose , Masami Ouchi

Recent work has shown that UV-luminous reionization-era galaxies often exhibit strong Lyman-alpha emission despite being situated at redshifts where the IGM is thought to be substantially neutral. It has been argued that this enhanced…