Related papers: X-rays from the High-Redshift Universe: The Chandr…
Using the Chandra ACIS-I instruments, we have carried out the deepest X-ray observation on a typical Galactic plane region at l 28.5 deg, where no discrete X-ray sources have been known previously. We have detected, as well as strong…
The more than 80 nearby galaxies imaged with the Chandra Advanced CCD Imaging Spectrometer have been analyzed in a search for Ultra-Luminous X-ray (ULX) sources. The sample of galaxies span the range of Hubble morphological types and…
We present {\it Chandra} X-ray Observatory observations of Giga-Hertz Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources. The {\it Chandra} sample contains 13 quasars and 3 galaxies with measured 2-10 keV X-ray luminosity…
We present Chandra observations of nine high-redshift quasars (z=2.7-5.9) discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra (WLQs). Adding archival X-ray observations of…
The high angular resolution and sensitivity of the Chandra X-ray Observatory has yielded large numbers of faint X-ray sources with measured redshifts in the soft (0.5-2 keV) and hard (2-8 keV) energy bands. Many of these sources show few…
Recent works have suggested that selection criteria based on MIR colors can be used to reveal a population of dust-enshrouded, extremely luminous quasars at z>1. However the X-ray spectral properties of these intriguing sources still remain…
Deep X-ray surveys are providing crucial information on the evolution of AGN and galaxies. We review some of the latest results based on the X-ray spectral analysis of the sources detected in the Chandra Deep Field South, namely: i)…
Northern auroral regions of Earth were imaged with energetic photons in the 0.1-10 keV range using the High-Resolution Camera (HRC-I) aboard the Chandra X-ray Observatory at 10 epochs (each ~20 min duration) between mid-December 2003 and…
We have performed a pilot Chandra survey of an off-center region of the Coma cluster to explore the X-ray properties and Luminosity Function of normal galaxies. We present results on 13 Chandra-detected galaxies with optical photometric…
Quasars selected in optical surveys by means of their blue or UV excess are known to be strong emitters in the X-rays, except for Broad Absorption Line (BAL) objects. In this paper we study the X-ray emission of quasars selected through…
The launch of the Chandra X-ray Observatory in July 1999 opened a new era in X-ray astronomy. Its unprecedented, <0.5" spatial resolution and low background are providing views of the X-ray sky 10-100 times fainter than previously possible.…
Compton Thick (CT) AGN are a key ingredient of Cosmic X-ray Background (CXB) synthesis models, but are still an elusive component of the AGN population beyond the local Universe. Multi-wavelength surveys are the only way to find them at z >…
We present results from the deep XMM-Newton observations of the two brightest X-ray sources in the Chandra Deep Field South (CDFS), PID 203 (z=0.544) and PID 319 (z=0.742). The long exposure of 2.5 Ms over a 10 year period (net 4 yr with a…
We have searched for X-ray jets in the recent Chandra observations of three Sloan Digital Sky Survey (SDSS) quasars at redshift z ~ 6. All 3 quasars were detected in X-rays in these relatively short observations. SDSS 1030+0524 is not…
We present X-ray source catalogs for the $\approx7$ Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 arcmin$^2$. Utilizing WAVDETECT for initial source detection and ACIS Extract for photometric…
To understand the Active Galactic Nuclei (AGN) phenomenon and their impact on the evolution of galaxies, a complete AGN census is required; however, finding heavily obscured AGNs is observationally challenging. Here we use the deep and…
We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg$^2$ Bo\"otes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the Universe at high…
We present the optical, near-infrared, submillimeter, and radio follow-up catalog of the X-ray selected sources from the 1 Ms Chandra observation of the Hubble Deep Field North region. We have B, V, R, I, and z' magnitudes for the 370 X-ray…
Models and observations suggest that luminous quasar activity is triggered by mergers, so it should preferentially occur in the most massive primordial dark matter haloes, where the frequency of mergers is expected to be the highest. Since…
We have investigated the jet-linked \mbox{X-ray} emission from highly radio-loud quasars (HRLQs; $\log R>2.5$) at high redshift. We studied the X-ray properties of 15 HRLQs at $z>4$, using new {\it Chandra} observations for six objects and…