Results 81 to 90 of about 4,173,094 (217)

Radio Spectroscopy of Active Galactic Nuclei

, 2005
Radio spectroscopy offers a number of tools for studying a large variety of astrophysical phenomena, ranging from stars and their environment to interstellar and intergalactic medium, active galactic nuclei (AGN) and distant quasars. Main targets of extragalactic radio spectroscopy are atomic and molecular material in galaxies, HII regions, and maser ...
openaire   +2 more sources

Challenges and Opportunities for Layered Double Perovskite Solar Cells

Solar RRL, Volume 10, Issue 17, 15 September 2026.
Layered lead‐free double perovskites suffer from intrinsic and extrinsic limitations that hinder high photovoltaic performance. This review identifies key challenges, including unfavorable band structures, strong self‐trapping, defect‐induced recombination, processing‐induced inhomogeneity, and device‐level mismatches.
Krishnaiah Mokurala, Marija Mrkonjić, Ceylan Doyranli, Jovana V. Milić, Mohammad Reza Golobostanfard   +4 more
wiley   +1 more source

OBSERVATIONAL EVIDENCE FOR ACTIVE GALACTIC NUCLEI FEEDBACK AT THE PARSEC SCALE

, 2011
In a hot accretion flow, the radiation from the innermost region of the flow propagates outward and heats the electrons at large radii via Compton scattering.
Miao Li, Feng Yuan, Yuan, Feng, Li, Miao
core   +1 more source

An Investigation of 5 yr Simultaneous X-Ray and Radio Light Curves of the Dwarf Seyfert Galaxy UGC 6728

The Astrophysical Journal
We present serendipitous simultaneous radio and X-ray light curves of the dwarf Seyfert galaxy UGC 6728 spanning 5 yr. The X-ray light curve exhibits a flaring period, followed by a gradual rise and decline.
Krista Lynne Smith, Macon Magno, Michael Koss   +2 more
doaj   +1 more source

Ultrafast Transitions in X‐Ray Irradiated Solids

Contributions to Plasma Physics, Volume 66, Issue 7-8, September 2026.
ABSTRACT In this review, we present current developments on modeling ultrafast transitions in solids triggered by intense, atto‐ to femtosecond pulses from X‐ray free electron lasers. This specific irradiation regime requires dedicated simulation tools based on theoretical and computational methods, involving the elements of classical and quantum ...
Sebastião Antunes, Konrad J. Kapcia, Vladimir Lipp, Beata Ziaja   +3 more
wiley   +1 more source

Compact Radio Sources, Quasars and Active Galactic Nuclei [PDF]

Australian Journal of Physics, 1994
This paper reviews John G. Bolton's contributions to our understanding of compact radio sources associated with quasars and active galactic nuclei (AGNs), and his work leading to the discovery of quasars. Particular attention is given to the interpretation of the observed properties of quasars and AGNs within the framework of unified models which ...
openaire   +1 more source

Late-time Radio Brightening and Emergence of a Radio Jet in the Changing-look AGN 1ES 1927+654

The Astrophysical Journal Letters
We present multifrequency (5–345 GHz) and multiresolution radio observations of 1ES 1927+654, widely considered one of the most unusual and extreme changing-look active galactic nuclei (CL-AGNs).
Eileen T. Meyer, Sibasish Laha, Onic I. Shuvo, Agniva Roychowdhury, David A. Green, Lauren Rhodes, Amelia M. Hankla, Alexander Philippov, Rostom Mbarek, Ari laor, Mitchell C. Begelman, Dev R. Sadaula, Ritesh Ghosh, Gabriele Bruni, Francesca Panessa, Matteo Guainazzi, Ehud Behar, Megan Masterson, Haocheng Zhang, Xiaolong Yang, Mark A. Gurwell, Garrett K. Keating, David Williams-Baldwin, Justin D. Bray, Emmanuel K. Bempong-Manful, Nicholas Wrigley, Stefano Bianchi, Federica Ricci, Fabio La Franca, Erin Kara, Markos Georganopoulos, Samantha Oates, Matt Nicholl, Main Pal, S. Bradley Cenko   +34 more
doaj   +1 more source

A Low‐Power Radioisotope XRF Spectrometer for Detection of Light Elements on Planetary Missions

X-Ray Spectrometry, Volume 55, Issue 5, Page 721-729, September/October 2026.
ABSTRACT Current X‐ray spectrometers for in situ geochemical analysis on planetary missions typically rely either on X‐ray tubes, which demand electrical power and add mass and thermal complexity, or on alpha particle X‐ray spectrometers (APXS) that use rare 244 Cm sources, and come with severe concerns on radiation safety and isotope availability.
Leandro Silveri, Artem Knyazev, Hashem Alaidaros, Maryam Manzoor Amanullah, Zach Ioannou, Tengiz Ibrayev, Danish Khan, Sara Leardini, Laura Manenti, Simi Maria Emilia Mangani, Safa Naseem, Sandhya Sharma, Sara Trevisan, Alia Zino, Francesco Arneodo   +14 more
wiley   +1 more source

The host galaxies of radio-loud active galactic nuclei: mass dependences, gas cooling and active galactic nuclei feedback [PDF]

Monthly Notices of the Royal Astronomical Society, 2005
The properties of the host galaxies of a well-defined sample of 2215 radio-loud active galactic nuclei (AGN) with redshifts 0.03 10 23 W Hz -1 is a strong function of stellar mass, rising from nearly zero below a stellar mass of 10 10 M○. to more than 30 per cent at stellar masses of 5 x 10 11 M○.. In contrast to the integrated [O III] luminosity
Best, P. N., Kauffmann, G., Heckman, T. M., Brinchmann, J., Charlot, S., Ivezić, Ž., White, S. D. M.   +6 more
openaire   +3 more sources

Searching for active galactic nuclei among unidentified INTEGRAL Sources [PDF]

, 2011
We report on a new method to identify active galactic nuclei (AGNs) among unidentified INTEGRAL sources. This method consists of cross-correlating unidentified sources listed in the fourth Imager on Board the INTEGRAL Satellite (IBIS) Survey Catalogue ...
Vahram Chavushyan
core