ﻻ يوجد ملخص باللغة العربية
We investigate the flux ratio between the 1335 A and 2326 A lines of singly ionized carbon in the extended narrow line regions of type 2 quasars at z~2.5. We find the observed CII 1335 / CII] 2326 flux ratio, which is not sensitive to the C/H abundance ratio, to be often several times higher than predicted by the canonical AGN photoionization models that use solar metallicity and a Maxwell-Boltzmann electron energy distribution. We study several potential solutions for this discrepancy: low gas metallicity, shock ionization, continuum fluorescence, and kappa-distributed electron energies. Although we cannot definitively distinguish between several of the proposed solutions, we argue that a kappa distribution gives the more natural explanation. We also provide a grid of AGN photoionization models using kappa-distributed electron energies.
The intrinsic column density (NH) distribution of quasars is poorly known. At the high obscuration end of the quasar population and for redshifts z<1, the X-ray spectra can only be reliably characterized using broad-band measurements which extend to
We present a survey of the [CII] 158 $mu$m line and underlying far-infrared (FIR) dust continuum emission in a sample of 27 z>6 quasars using the Atacama Large Millimeter Array (ALMA) at ~1 resolution. The [CII] line was significantly detected (at >5
We present a search for CO emission in a sample of ten type-2 quasar host galaxies with redshifts of z=0.1-0.4. We detect CO(J=1-0) line emission with >=5sigma in the velocity integrated intensity maps of five sources. A sixth source shows a tentativ
Using the prospector spectral energy distribution (SED) fitting code, we analyze the properties of 19 Extreme Emission Line Galaxies (EELGs) identified in the bluest composite SED in the zfourge survey at $2.5 leq z leq 4$. prospector includes a phys
We have obtained H-band spectra of 32 luminous quasars at 2.0<z<2.5 with the Multiple Mirror Telescope. The sample contains 15 radio-loud quasars (RLQs) and 17 radio-quiet quasars (RQQs). We have measured emission line properties from the rest-frame