activity
20152026
most citedFirst Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way

1.9k citations · 12k across the 63 of their papers we have counts for

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Showing 2018Show all

6 papers · 1 filter

astro-ph.GA2018

The Scattering and Intrinsic Structure of Sagittarius A* at Radio Wavelengths

Michael D. Johnson, Ramesh Narayan, Dimitrios Psaltis +12

Radio images of the Galactic Center supermassive black hole, Sagittarius A* (Sgr A*), are dominated by interstellar scattering. Previous studies of Sgr A* have adopted an anisotrop…

astro-ph.GA2018

Exploring the Nature of the 2016 γ-ray Emission in the Blazar 1749+096

Dae-Won Kim, Sascha Trippe, Sang-Sung Lee +9

Recent Fermi-Large Area Telescope (LAT) light curves indicate an active -ray state spanning about five months from 2016 June to 2016 October in the BL Lac object 1749+096 (OT 08…

astro-ph.HE2018

Revealing the Nature of Blazar Radio Cores through Multi-Frequency Polarization Observations with the Korean VLBI Network

Jongho Park, Minchul Kam, Sascha Trippe +13

We study the linear polarization of the radio cores of eight blazars simultaneously at 22, 43, and 86 GHz with observations obtained by the Korean VLBI Network (KVN) in three epoch…

astro-ph.HE2018

Exploring the Variability of the Flat Spectrum Radio Source 1633+382. II: Physical Properties

Juan-Carlos Algaba, Sang-Sung Lee, Bindu Rani +13

The flat spectrum radio quasar 1633+382 (4C~38.41) showed a significant increase of its radio flux density during the period 2012 March - 2015 August which correlates with gamma-ra…

astro-ph.HE2018

KVN observations suggest multiple -ray emission regions in 3C 84

Jeffrey A. Hodgson, Bindu Rani, Sang-Sung Lee +15

3C 84 (NGC 1275) is a well-studied mis-aligned Active Galactic Nucleus (AGN), which has been active in Gamma rays since at least 2008. We have monitored the source at four waveleng…

astro-ph.GA2018

Long-term millimeter VLBI monitoring of M87 with KVN at milliarcsecond resolution: nuclear spectrum

Jae-Young Kim, Sang-Sung Lee, Jeffrey A. Hodgson +5

We study the centimeter- to millimeter-wavelength synchrotron spectrum of the core of the radio galaxy M87 at spatial scales using four years…