45 citations · 476 across the 38 of their papers we have counts for
15 papers · 1 filter
Cosmological Distance Measurements of High Redshift Blazars: OJ 248 (z=0.939) and 4C +38.41 (z=1.814)
Young-Bin Shin, Sang-Sung Lee, Sincheol Kang +3
In this study, we estimated the angular diameter distances to two high-redshift active galactic nuclei (AGNs), OJ 248 (z = 0.939) and 4C +38.41 (z = 1.814), using 43 GHz radio ligh…
A distance measurement for blazar TXS 0506+056 using its radio variability and very long baseline images
Chanwoo Song, Sang-Sung Lee, Sincheol Kang +1
We present the results of constraining the angular diameter distance to blazar TXS 0506+056. We used data obtained with the 15 GHz VLBA in MJD 54838-60262 and data from the 15 GHz…
The variability angular diameter distance and the intrinsic brightness temperature of active galactic nuclei
Whee Yeon Cheong, Sang-Sung Lee, Chanwoo Song +5
Context. It has recently been suggested that angular diameter distances derived from comparing the variability timescales of blazars to angular size measurements with very long bas…
Polarization flare of 3C 454.3 in millimeter wavelengths seen from decadal polarimetric observations
Hyeon-Woo Jeong, Sang-Sung Lee, Sincheol Kang +6
This study investigates polarimetric characteristics of the blazar 3C~454.3 at 22-129~GHz using decadal~(2011-2022) data sets. In addition, we also delve into the origin of the pol…
Using the Crab Nebula as Polarization Angle Calibrator for the Korean VLBI Network
Minchul Kam, Sascha Trippe, Do-Young Byun +5
The Crab nebula is widely used as a polarization angle calibrator for single-dish radio observations because of its brightness, high degree of linear polarization, and well-known p…
Interferometric Monitoring of Gamma-ray Bright AGNs: OJ 287
Jee Won Lee, Sang-Sung Lee, Juan-Carlos Algaba +9
We present the results of simultaneous multi-frequency imaging observations at 22, 43, 86, and 129\,GHz of OJ\,287. We used the Korean VLBI Network as part of the Interferometric M…
Origin and Evolution of the Multi-band Variability in the Flat Spectrum Radio Source 4C 38.41
Juan Carlos Algaba, Sang Sung Lee, Bindu Rani +13
The flat spectrum radio quasar 4C 38.41 showed a significant increase of its radio flux density during the period 2012 March - 2015 August which correlates with gamma-ray flaring a…
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…
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…
The Millimeter-Radio Emission of BL Lacertae During Two gamma-ray Outbursts
Dae-Won Kim, Sascha Trippe, Sang-Sung Lee +13
We present a study of the inexplicit connection between radio jet activity and gamma-ray emission of BL Lacertae (BL Lac; 2200+420). We analyze the long-term millimeter activity of…
Interferometric Monitoring of Gamma-ray Bright AGNs: S5 0716+714
Jee Won Lee, Sang-Sung Lee, Jeffrey A. Hodgson +5
We present the results of very long baseline interferometry (VLBI) observations of gamma-ray bright blazar S5 0716+714 using the Korean VLBI Network (KVN) at the 22, 43, 86, and 12…
Interferometric Monitoring of Gamma-ray Bright AGNs I: Results of Single-epoch Multifrequency Observations
Sang-Sung Lee, Kyoaki Wajima, Juan-Carlos Algaba +12
We present results of single-epoch very long baseline interferometry (VLBI) observations of gamma-ray bright active galactic nuclei (AGNs) using the Korean VLBI Network (KVN) at 22…
Monitoring of GAmma-ray Bright AGN : The Multi-frequency Polarization of the Flaring Blazar 3C 279
Sincheol Kang, Sang-Sung Lee, Do-Young Byun
We present results of long-term multi-wavelength polarization observations of the powerful blazar 3C~279 after its -ray flare on 2013~December 20. We followed up this flare with…
PAGaN II: The Evolution of AGN Jets on Sub-Parsec Scales
Junghwan Oh, Sascha Trippe, Sincheol Kang +7
We report first results from KVN and VERA Array (KaVA) VLBI observations obtained in the frame of our Plasma-physics of Active Galactic Nuclei (PAGaN) project. We observed eight se…
First Detection of 350 Micron Polarization From a Radio-loud AGN
Sang-Sung Lee, Sincheol Kang, Do-Young Byun +5
We report the first detection of linearly polarized emission at an observing wavelength of 350 m from the radio-loud Active Galactic Nucleus 3C 279. We conducted polarization ob…