Related papers: Lyman Alpha Constraints on Very Low Luminosity AGN

We determine the evolution of the faint, high-redshift, optical luminosity function (LF) of AGN implied by several observationally-motivated models of the ionizing background. Our results depend crucially on whether we use the total…

We present new results from the widest narrow band survey search for Lyman-alpha (Lya) emitters at z=5.7, just after reionization. We survey a total of 7 deg$^2$ spread over the COSMOS, UDS and SA22 fields. We find over 11,000 line…

Using the results of recent optical surveys we conclude that the {\it non}-detection of quasars down to faint magnitudes implies a significant flattening of the high redshift (z~6) optical active galactic nuclei (AGN) luminosity function…

We present detection and analysis of faint X-ray sources in the Chandra deep field south (CDFS) using the 4 Msec Chandra observation and adopting a new detection algorithm, based on a targeted search at the position of known high-z…

We present new Keck/MOSFIRE K-band spectroscopy for a sample of 14 faint, X-ray-selected active galactic nuclei (AGNs) in the COSMOS field. The data cover the spectral region surrounding the broad Balmer emission lines, which enables the…

We present the Lya luminosity functions (LFs) derived by our deep Subaru narrowband survey that identifies a total of 3,137 Lya emitters (LAEs) at $z = 2.2$ in five independent blank fields. The sample of these LAEs is the largest, to date,…

We report the first direct and robust measurement of the faint-end slope of the Lyman-alpha emitter (LAE) luminosity function at z = 5.7. Candidate LAEs from a low-spectral-resolution blind search with IMACS on Magellan-Baade were targeted…

Lyman alpha (Lya) emission lines should be attenuated in a neutral intergalactic medium (IGM). Therefore the visibility of Lya emitters at high redshifts can serve as a valuable probe of reionization at about the 50% level. We present an…

We have used XMM-Newton to observe six Lyman Break Analogs (LBAs): members of the rare population of local galaxies that have properties that are very similar to distant Lyman Break Galaxies. Our six targets were specifically selected…

We present a study on stellar properties of Lyman-alpha (Ly$\alpha$) emitters at 5 $< z <$ 8.2. We use 247 photometrically-selected, lensed, high-redshift, low luminosity galaxy candidates with spectroscopic follow-up. Of these, 38 are…

We present a first statistical sample of faint type-1 AGNs at $z>4$ identified by JWST/NIRSpec deep spectroscopy. Among the 185 galaxies at $z_\mathrm{spec}=3.8-8.9$ confirmed with NIRSpec, our systematic search for broad-line emission…

Deep narrow-band surveys have revealed a large population of faint Lyman-alpha (Lya) emitters (LAEs) in the distant Universe, but relatively little is known about the most luminous sources ($L_{Ly\alpha}>10^{42.7}$ erg/s;…

We report the discovery of Lyman alpha emission from a galaxy at z=5.34, the first object at z>5 with a spectroscopically confirmed redshift. The faint continuum emission (m(8000A)=27 AB mag), relatively small rest-frame equivalent width of…

We discuss a sample of 29 AGN (16 narrow-lined and 13 broad-lined) discovered in a spectroscopic survey of ~1000 star-forming Lyman-break galaxies (LBGs) at z~3. Reaching apparent magnitudes of R_{AB}=25.5, the sample includes broad-lined…

We present luminosity functions (LFs) and various properties of Lya emitters (LAEs) at z=3.1, 3.7, and 5.7, in a 1 deg^2 sky of the Subaru/XMM-Newton Deep Survey (SXDS) Field. We obtain a photometric sample of 858 LAE candidates based on…

The Lyman-alpha emitters found at z ~ 4.5 by the Large Area Lyman Alpha (LALA) survey have high equivalent widths in the Lyman-alpha line, which can be produced by either narrow-lined active galactic nuclei (AGNs) or by stellar populations…

Recent wide-field integral field spectroscopy has revealed the detailed properties of high redshift Lyman-alpha (Lya) nebulae, most often targeted due to the presence of an active galactic nucleus (AGN). Here, we use VLT/MUSE to resolve the…

We have determined the cosmological evolution of the density of AGN and of their Nh distribution as a function of the un-absorbed 2-10 keV luminosity up to redshift 4. We used the HELLAS2XMM sample combined with other published catalogs,…

Lyman Alpha Emitters (LAEs) are usually thought to be powered by star formation. It has been recently reported that a fraction of LAEs at redshift z~3-4 hosts an Active Galactic Nuclei (AGN). If an AGN is present it could be obscured and…

We combine Lyman-break colour selection with ultradeep (> 200 ks) Chandra X-ray imaging over a survey area of ~0.35 deg^2 to select high redshift AGN. Applying careful corrections for both the optical and X-ray selection functions, the data…