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A Closer Look at Two of the Most Luminous Quasars in the Universe
Fan, Xiaohui; Huang, Yun-Hsin; Walter, Fabian +7 more
Ultraluminous quasars (M1450 ≤ -29) provide us with a rare view into the nature of the most massive and most rapidly accreting supermassive black holes (SMBHs). Following the discovery of two of these extreme sources, J0341+1720 (M1450 = -29.56, z = 3.71) and J2125-1719 (M1450 = -29.39, z = 3.90), in the Extremely …
Are Compton-thin AGNs Globally Compton Thin?
Yukita, M.; Ptak, A.; LaMassa, S. +2 more
We select eight nearby active galactic nuclei (AGNs) which, based on previous work, appear to be Compton-thin in the line of sight. We model with MYTORUS their broadband X-ray spectra from 20 individual observations with Suzaku, accounting self-consistently for Fe Kα line emission, as well as direct and scattered continuum from matter with finite …
A Perspective on the Scaling of Magnetosheath Turbulence and Effects of Bow Shock Properties
Voitcu, Gabriel; Echim, Marius; Teodorescu, Eliza
We analyze magnetic field data from two magnetosheath crossings, representative of a larger collection of similar cases in the database of the Cluster spacecraft. We apply a novel data analysis method to identify the power-law behavior of the structure functions and to find the validity range of the power-law scaling. We validate the technique wit…
Eclipsing Binaries in the Open Cluster Ruprecht 147. IV: The Active Triple System EPIC 219511354
Torres, Guillermo; Vanderburg, Andrew; Gaidos, Eric +2 more
We report follow-up spectroscopic observations of the 1.62 day, K-type, detached, active, near-circular, double-lined eclipsing binary EPIC 219511354 in the open cluster Ruprecht 147, identified previously on the basis of photometric observations from the Kepler/K2 mission. This is the fourth eclipsing system analyzed in this cluster. A combined a…
A Weakening Compton Hump and Soft X-Ray Excess Detected in the Seyfert 1 Galaxy MCG -02-58-22
Laha, Sibasish; Ghosh, Ritesh
We have carried out an extensive X-ray spectral study of the bare Seyfert 1 galaxy MCG -02-58-22 to ascertain the nature of the X-ray reprocessing media using observations from Suzaku (2009) and simultaneous observations from XMM-Newton and NuSTAR (2016). The most significant results of our investigation are as follows. (1) The primary X-ray emiss…
Broadband Modeling of Low-luminosity Active Galactic Nuclei Detected in Gamma Rays
Prince, Raj; Tomar, Gunjan; Gupta, Nayantara
Low-luminosity active galactic nuclei are more abundant and closer to us than the luminous ones but harder to explore as they are faint. We have selected the four sources, NGC 315, NGC 4261, NGC 1275, and NGC 4486, which have been detected in γ-rays by Fermi-LAT. We have compiled their long-term radio, optical, X-ray data from different telescopes…
Properties of the C II 1334 Å Line in Coronal Hole and Quiet Sun as Observed by IRIS
Tripathi, Durgesh; Upendran, Vishal
Coronal holes (CHs) have subdued intensity and net blueshifts when compared to the quiet Sun (QS) at coronal temperatures. At transition region temperatures, such differences are obtained for regions with identical absolute photospheric magnetic flux density (∣B∣). In this work, we use spectroscopic measurements of the C II 1334 Å line from the In…
DIISC-II: Unveiling the Connections between Star Formation and Interstellar Medium in the Extended Ultraviolet Disk of NGC 3344
Heckman, Timothy; Kennicutt, Robert C.; Thilker, David +6 more
We present our investigation of the extended ultraviolet (XUV) disk galaxy, NGC 3344, conducted as part of Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium survey. We use surface and aperture photometry of individual young stellar complexes to study star formation and its effect on the physical proper…
Reaching the Oldest Stars beyond the Local Group: Ancient Star Formation in UGC 4483
Aloisi, Alessandra; Cignoni, Michele; Sacchi, Elena +9 more
We present new WFC3/UVIS observations of UGC 4483, the closest example of a metal-poor blue compact dwarf galaxy, with a metallicity of Z ≃ 1/15 Z⊙ and located at a distance of D ≃ 3.4 Mpc. The extremely high quality of our new data allows us to clearly resolve the multiple stellar evolutionary phases populating the color-magnitude diag…
X-Ray Binaries in M51 I: Catalog and Statistics
Chandar, Rupali; Rangelov, Blagoy; Prestwich, Andrea +3 more
We used archival data from the Chandra X-ray Observatory (Chandra) and the Hubble Space Telescope, to identify 334 candidate X-ray binary systems and their potential optical counterparts in the interacting galaxy pair NGC 5194/5195 (M51). We present the catalog and data analysis of X-ray and optical properties for those sources, from the deep 892 …