Results 41 to 50 of about 112,522 (249)

Circum-Galactic Medium in the Halo of Quasars

Frontiers in Astronomy and Space Sciences, 2017
The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars.
Riccardo Ottolina, Renato Falomo, Aldo Treves, Michela Uslenghi, Jari K. Kotilainen, Riccardo Scarpa, Emanuele Paolo Farina   +6 more
doaj   +1 more source

What We Talk about When We Talk about Blazars?

Frontiers in Astronomy and Space Sciences, 2017
After the discovery of powerful relativistic jets from Narrow-Line Seyfert 1 Galaxies, and the understanding of their similarity with those of blazars, a problem of terminology was born.
Luigi Foschini
doaj   +1 more source

Model simulation of heavy metals in river systems: case study the Negro river basin

Revista Facultad de Ingeniería Universidad de Antioquia, 2019
Este trabajo describe la aplicación de un modelo de calidad de agua para la simulación de metales pesados en sistemas fluviales. La estrategia propuesta incluye un enfoque de modelación 1D con la extensión del modelo QUASAR-ADZ para la representación del
Carlos Alberto Palacio-Tobón, Sara Cristina Vieira-Agudelo, Julio Cesar Saldarriaga-Molina, Luis Miguel Ruiz-Jaramillo   +3 more
doaj   +1 more source

The Sloan Digital Sky Survey Quasar Catalog: Twelfth data release [PDF]

, 2016
We present the Data Release 12 Quasar catalog (DR12Q) from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III. This catalog includes all SDSS-III/BOSS objects that were spectroscopically targeted as quasar candidates ...
I. Pâris, I. Pâris, P. Petitjean, Nic Ross, Nic Ross, A. Myers, A. Myers, E. Aubourg, A. Streblyanska, A. Streblyanska, S. Bailey, E. Armengaud, N. Palanque-Delabrouille, C. Yéche, F. Hamann, M. Strauss, F. D. Albareti, J. Bovy, D. Bizyaev, D. Bizyaev, W. Brandt, M. Brusa, M. Brusa, J. Buchner, J. Comparat, R. Croft, T. Dwelly, Xiaohui Fan, A. Font-Ribera, J. Ge, A. Georgakakis, P. Hall, Linhua Jiang, K. Kinemuchi, E. Malanushenko, V. Malanushenko, R. McMahon, M. Menzel, A. Merloni, K. Nandra, P. Noterdaeme, D. Oravetz, K. Pan, M. Pieri, Francisco Prada, Francisco Prada, M. Salvato, D. Schlegel, D. Schneider, A. Simmons, M. Viel, D. Weinberg, Liu Zhu   +52 more
semanticscholar   +1 more source

Cosmology With Quasars: Predictions for eROSITA From a Quasar Hubble Diagram

Frontiers in Astronomy and Space Sciences, 2020
The effort for understanding the matter and energy content of the Universe and its evolution relies on different probes, such as cosmic background radiation, cluster lensing, supernovae.
Elisabeta Lusso, Elisabeta Lusso
doaj   +1 more source

Compatibility of the large quasar groups with the concordance cosmological model [PDF]

, 2016
We study the compatibility of large quasar groups with the concordance cosmological model. Large quasar groups are very large spatial associations of quasars in the cosmic web, with sizes of 50–250 h−1 Mpc.
Campusano, Luis E., Clowes, Roger G., Graham, Matthew J., Marinello, Gabriel E., Söchting, Ilona K., Williger, Gerard M.   +5 more
core   +2 more sources

Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). V. Quasar Luminosity Function and Contribution to Cosmic Reionization at z = 6 [PDF]

Astrophysical Journal, 2018
We present new measurements of the quasar luminosity function (LF) at z ∼ 6 over an unprecedentedly wide range of the rest-frame ultraviolet luminosity M1450 from −30 to −22 mag.
Y. Matsuoka, M. Strauss, N. Kashikawa, M. Onoue, K. Iwasawa, Ji-Jia Tang, Chien-Hsiu Lee, M. Imanishi, T. Nagao, M. Akiyama, N. Asami, J. Bosch, H. Furusawa, T. Goto, J. Gunn, Y. Harikane, H. Ikeda, T. Izumi, T. Kawaguchi, N. Kato, S. Kikuta, K. Kohno, Y. Komiyama, R. Lupton, T. Minezaki, S. Miyazaki, H. Murayama, M. Niida, A. Nishizawa, Akatoki Noboriguchi, M. Oguri, Y. Ono, M. Ouchi, P. Price, H. Sameshima, A. Schulze, H. Shirakata, J. Silverman, N. Sugiyama, Philip J. Tait, M. Takada, T. Takata, Masayuki Tanaka, Y. Toba, Y. Utsumi, Shiang‐Yu Wang, T. Yamashita   +46 more
semanticscholar   +1 more source

Large-scale homogeneity in the distribution of quasars in the Hercules-Corona Borealis Great Wall region [PDF]

Serbian Astronomical Journal, 2022
In light of recent debates on the existence of a gigaparsec-scale structure traced by gamma-ray bursts, namely the Hercules-Corona Borealis Great Wall (HCBGW), we revisit large-scale homogeneity in the spatial distribution of quasars. Our volume-
Fujii Hirokazu
doaj   +1 more source

Comparative evaluation of volume and helical four-dimensional computed tomography using canon system. [PDF]

J Appl Clin Med Phys
Abstract Background Four‐dimensional computed tomography (4DCT) is an advanced imaging technique designed to capture anatomical motion over time, enabling more accurate evaluation of tumor and organ motion owing to respiration, while minimizing motion‐related artifacts.
Kim C, Lee E, Yu JH, Kim H, Park S, Han S, Kim TH, Han MC, Hong CS, Kim JS.   +9 more
europepmc   +2 more sources

Discovery of the First Low-luminosity Quasar at z > 7 [PDF]

Astrophysical Journal, 2019
We report the discovery of a quasar at z = 7.07, which was selected from the deep multi-band imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey.
Y. Matsuoka, M. Onoue, N. Kashikawa, M. Strauss, K. Iwasawa, Chien-Hsiu Lee, M. Imanishi, T. Nagao, M. Akiyama, N. Asami, J. Bosch, H. Furusawa, T. Goto, J. Gunn, Y. Harikane, H. Ikeda, T. Izumi, T. Kawaguchi, N. Kato, S. Kikuta, K. Kohno, Y. Komiyama, S. Koyama, R. Lupton, T. Minezaki, S. Miyazaki, H. Murayama, M. Niida, A. Nishizawa, Akatoki Noboriguchi, M. Oguri, Y. Ono, M. Ouchi, P. Price, H. Sameshima, A. Schulze, H. Shirakata, J. Silverman, N. Sugiyama, Philip J. Tait, M. Takada, T. Takata, Masayuki Tanaka, Ji-Jia Tang, Y. Toba, Y. Utsumi, Shiang‐Yu Wang, T. Yamashita   +47 more
semanticscholar   +1 more source