Results 101 to 110 of about 1,919 (235)

Strong Amplitude Modulation of Hard-band X-Ray Quasiperiodic Oscillation with Soft-band Flux in RE J1034+396

The Astrophysical Journal
The X-ray quasiperiodic oscillation (QPO) is a remarkable form of variability in systems of compact object accretion. RE J1034+396, harboring the most significant X-ray QPO in active galactic nuclei (AGNs), is the most noteworthy source for in-depth ...
Ruisong Xia, Hao Liu, Yongquan Xue
doaj   +1 more source

X-ray versus optically selected active galactic nuclei: a comparative study of the luminosity functions and evolution rates [PDF]

, 1994
A. Franceschini, F. La Franca, S. Cristiani, J. M. Martín-Mirones   +3 more
openalex   +1 more source

PEARLS: NuSTAR and XMM-Newton Extragalactic Survey of the JWST North Ecliptic Pole Time-domain Field II

The Astrophysical Journal
We present the second NuSTAR and XMM-Newton extragalactic survey of the JWST north ecliptic pole (NEP) time-domain field (TDF). The first NuSTAR NEP-TDF survey had 681 ks total exposure time executed in NuSTAR cycle 5 in 2019 and 2020. This second survey,
Xiurui Zhao, Francesca Civano, Christopher N. A. Willmer, Silvia Bonoli, Chien-Ting Chen, Samantha Creech, Renato Dupke, Francesca M. Fornasini, Rolf A. Jansen, Satoshi Kikuta, Anton M. Koekemoer, Sibasish Laha, Stefano Marchesi, Rosalia O’Brien, Ross Silver, S. P. Willner, Rogier A. Windhorst, Haojing Yan, Jailson Alcaniz, Narciso Benitez, Saulo Carneiro, Javier Cenarro, David Cristóbal-Hornillos, Alessandro Ederoclite, Antonio Hernán-Caballero, Carlos López-Sanjuan, Antonio Marín-Franch, Claudia Mendes de Oliveira, Mariano Moles, Laerte Sodré Jr., Keith Taylor, Jesús Varela, Héctor Vázquez Ramió   +32 more
doaj   +1 more source

X-Ray Spectra and Time Variability of Active Galactic Nuclei [PDF]

, 1993
R. F Mushotzky
openalex   +1 more source

The Prospects Of X-Ray Polarimetry For Active Galactic Nuclei

, 2016
Polarimetry at optical and other wavelength continues to play an important role in our struggle to develop (super-)unification schemes for active galactic nuclei (AGN). Therefore, radio-loud and radio-quiet AGN are important targets for the future small and medium-size X-ray polarimetry missions that are currently under phase A study at NASA and ESA ...
openaire   +2 more sources

Chandra X-Ray Observatory Study of the X-Ray Emission of PKS 0023−26 and Comparison with Recent ALMA Results

The Astrophysical Journal
We present a deep high-resolution Chandra X-ray Observatory study of the powerful compact radio source PKS 0023−26 associated with a quasar at redshift 0.322.
A. Siemiginowska, R. Morganti, G. Fabbiano, E. O’Sullivan, T. Oosterloo, C. Tadhunter, D. Burke   +6 more
doaj   +1 more source

Signature of a Seyfert-like Component in Blazar 3C 273 and Its Reflection-based Explanation

The Astrophysical Journal
We present the results of blazar 3C 273 from simultaneous observations obtained using the XMM-Newton and NuSTAR satellites during the period 2015–2019 in five epochs. When the spectra are modeled with a power law, significant residuals arise below ∼2 keV
Haritma Gaur, Main Pal, Muhammad S. Anjum, Kiran Wani, Pankaj Kushwaha, Ashwani Pandey, Liang Chen   +6 more
doaj   +1 more source

An X‐Ray Spectral Survey of Radio‐loud Active Galactic Nuclei withASCA [PDF]

, 1999
R. M. Sambruna, Michael Eracleous, R. F. Mushotzky   +2 more
openalex   +1 more source

BASS. XLVIII. [Ne V] λ3427 Emission in Powerful Nearby Active Galactic Nuclei

The Astrophysical Journal
We investigate the high-ionization, narrow [Ne V ] λ 3427 line emission in a sample of over 340 ultrahard X-ray (14–195 keV) selected active galactic nuclei (AGN) drawn from the BAT AGN Spectroscopic Survey project.
Tomer Reiss, Benny Trakhtenbrot, Claudio Ricci, Franz E. Bauer, Michael J. Koss, Kohei Ichikawa, Darshan Kakkad, Richard Mushotzky, Kyuseok Oh, Alessandro Peca, Rudolf Bär, Yaherlyn Diaz, Fiona Harrison, Meredith C. Powell, Eleonora Sani, Daniel Stern, C. Megan Urry   +16 more
doaj   +1 more source

X‐Ray Lines in Active Galactic Nuclei and Photoionized Gases [PDF]

, 1996
H. Netzer
openalex   +1 more source