Results 81 to 90 of about 80,128 (249)

PEARLS: Discovery of Point-source Features within Galaxies in the North Ecliptic Pole Time Domain Field

The Astrophysical Journal
The first public 0.9–4.4 μ m NIRCam images of the North Ecliptic Pole Time Domain Field uncovered galaxies displaying point-source features in their cores as seen in the longer-wavelength filters. We visually identified a sample of 66 galaxies (∼1 galaxy
Rafael Ortiz III, Rogier A. Windhorst, Seth H. Cohen, Steven P. Willner, Rolf A. Jansen, Timothy Carleton, Patrick S. Kamieneski, Michael J. Rutkowski, Brent M. Smith, Jake Summers, Cheng Cheng, Dan Coe, Christopher J. Conselice, Jose M. Diego, Simon P. Driver, Jordan C. J. D’Silva, Brenda L. Frye, Hansung B. Gim, Norman A. Grogin, Heidi B. Hammel, Nimish P. Hathi, Benne W. Holwerda, Minhee Hyun, Myungshin Im, William C. Keel, Anton M. Koekemoer, Juno Li, Madeline A. Marshall, Tyler J. McCabe, Noah J. McLeod, Stefanie N. Milam, Rosalia O’Brien, Nor Pirzkal, Aaron S. G. Robotham, Russell E. Ryan Jr., Christopher N. A. Willmer, Haojing Yan, Min S. Yun, Adi Zitrin   +38 more
doaj   +1 more source

Flux States of Active Galactic Nuclei

Galaxies, 2019
Blazars are known to show variability on time scales from minutes to years covering a wide range of flux states. Studying the flux distribution of a source allows for various insights.
Daniela Dorner, Axel Arbet-Engels, Dominik Baack, Matteo Balbo, Adrian Biland, Michael Blank, Thomas Bretz, Kai Bruegge, Michael Bulinski, Jens Buss, Manuel Doerr, Dominik Elsaesser, Dorothee Hildebrand, Lena Linhoff, Karl Mannheim, Sebastian Achim Mueller, Dominik Neise, Andrii Neronov, Maximilian Noethe, Aleksander Paravac, Wolfgang Rhode, Bernd Schleicher, Florian Schulz, Kevin Sedlaczek, Amit Shukla, Vitalii Sliusar, Elan von Willert, Roland Walter, FACT Collaboration   +28 more
doaj   +1 more source

The Correlation between X-ray spectral slope and FeKalpha line energy in radio-quiet active galactic nuclei

, 2002
A significant correlation between FeKalpha line energy and X-ray spectral slope has been discovered among radio-quiet active galactic nuclei. The ionization stage of the bulk of the FeKalpha emitting material is not the same in all active galactic nuclei
Arnaud K. A., Boller T., Brandt W. N., Fabian A. C., George I. M., Grupe D., Guainazzi M., Guilbert P. W., Gulab Chand Dewangan, Koenig M., Mineo T., Pounds K. A., Reynolds C. S., Winkler H., Wisotzki L.   +14 more
core   +1 more source

Active Galactic Nuclei

, 2013
This final chapter introduces a classical example of sources emitting high energy radiation. A strong effort has been made to introduce these sources at a basic level: no pre-knowledge is required. They are one of the best fields of research where we can use what studied in all the previous chapters: we will apply the just learnt theory to the most ...
  +4 more sources

A Catalog of Broad Hα and Hβ Active Galactic Nuclei in MaNGA

The Astrophysical Journal
Broad H α and H β emission lines (FWHM > 1000 km s ^−1 ) are incredibly efficient tracers of the high-velocity clouds encircling active galactic nuclei (AGNs).
James Negus, Julia M. Comerford, Francisco Müller Sánchez   +2 more
doaj   +1 more source

Revisiting the Unified Model of Active Galactic Nuclei [PDF]

, 2015
Hagai Netzer
openalex   +1 more source

Studies of active galactic nuclei with CTA

, 2012
In this paper, we review the prospects for studies of active galactic nuclei (AGN) using the envisioned future Cherenkov Telescope Array (CTA). This review focuses on jetted AGN, which constitute the vast majority of AGN detected at gamma-ray energies ...
A. Reimer, Abdo, Abdo, Abdo, Abdo, Abdo, Abdo, Abdo, Abdo, Abdo, Abdo, Acciari, Ackermann, Ackermann, Aharonian, Aharonian, Aharonian, Aharonian, Albert, Albert, Albert, Aleksic, Aleksic, Araudo, Atoyan, Baring, Barkov, Beall, Bednarek, Bednarek, Bednarek, Blandford, Blandford, Blażejowski, Bloom, Böttcher, Böttcher, Böttcher, Böttcher, Böttcher, Böttcher, Capetti, Cavaliere, Celotti, Chiaberge, Chiaberge, De Angelis, Dermer, Dermer, Dermer, Dermer, Dwek, Eichler, Ellison, Essey, Fanaroff, Finke, Fossati, Franceschini, Georganopoulos, Ghisellini, Ghisellini, Ghisellini, Giannios, Gilmore, Giommi, Kirk, Königl, Landt, Li, M. Böttcher, Mannheim, Maraschi, Marscher, Mücke, Mücke, Mücke, Ostrowski, Padovani, Pian, Pohl, Poutanen, Protheroe, Rau, Rawling, Reimer, Reimer, Reynoso, Romani, Roustazadeh, Roustazadeh, Sikora, Simet, Sitarek, Stawarz, Stecker, Stecker, Takahashi, Urry   +98 more
core   +1 more source

Identifying the Secondary Jet in the RadioAstron Image of OJ 287

The Astrophysical Journal
The 136 yr long optical light curve of OJ 287 is explained by a binary black hole model where the secondary is in a 12 yr orbit around the primary. Impacts of the secondary on the accretion disk of the primary generate a series of optical flares that ...
Mauri J. Valtonen, Lankeswar Dey, Staszek Zola, Alok C. Gupta, Shubham Kishore, Achamveedu Gopakumar, Paul J. Wiita, Minfeng Gu, Kari Nilsson, Zhongli Zhang, Rene Hudec, Katsura Matsumoto, Marek Drozdz, Waldemar Ogloza, Andrei V. Berdyugin, Daniel E. Reichart, Markus Mugrauer, Tapio Pursimo, Stefano Ciprini, Tatsuya Nakaoka, Makoto Uemura, Ryo Imazawa, Michal Zejmo, Vladimir V. Kouprianov, James W. Davidson Jr., Alberto Sadun, Jan Štrobl, Martin Jelínek, Abhimanyu Susobhanan   +28 more
doaj   +1 more source

The environment of active galactic nuclei – I. A two-component broad emission line model [PDF]

, 1988
S. Collin-Souffrin, J. E. Dyson, Jonathan McDowell, J. J. Perry   +3 more
openalex   +1 more source

Probing the Dust Torus Radius–Luminosity Relation: A WISE View

The Astrophysical Journal
We present measurements of the dusty torus sizes of 51 active galactic nuclei (AGNs) with a redshift of z  
Ashutosh Tomar, Suvendu Rakshit, Amit Kumar Mandal, Shivangi Pandey   +3 more
doaj   +1 more source