35 citations · 64 across the 23 of their papers we have counts for
8 papers · 1 filter
The 2015-2017 Large EVPA Rotation in OJ 287: Dominant Propagating Component in a Helical Magnetic Field with Time-Dependent Viewing Geometry
Wanchaloem Khwammai, Minchul Kam, Motoki Kino +11
We present high-cadence, multi-frequency monitoring of the blazar OJ 287 using KVN (22--129 GHz), ALMA (91.5--343.5 GHz), and Metsähovi (37 GHz), covering 2012--2023, together with…
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 Universal Physics Defining the Radiation Spectra of Blazars and Gamma-Ray Bursts
Z. Lucas Uhm, Sang-Sung Lee, Bing Zhang +5
Blazars and gamma-ray bursts (GRBs) are both cosmic beacons of extreme energy release powered by relativistic jets. However, they originate from tremendously different environments…
The Celestial Reference Frame at K Band: The CRF-K-2025 Catalog
David Gordon, Aletha de Witt, Christopher S. Jacobs +10
We present an updated K band (24 GHz) celestial reference frame (CRF) constructed from 3.5 million Very Long Baseline Interferometry (VLBI) observations collected during 211 observ…
Constraining the magnetic field strength of a flaring radio core in the compact steep spectrum source 3C 138
Shan Li, Sang-Sung Lee, Whee Yeon Cheong +3
Compact steep spectrum (CSS) sources generally show weak Doppler boosting, yet some exceptions show multi-year-scale radio flux variability and high-energy activity. Since 2022, th…
Verification of the Polarimetric Capability of the East Asia VLBI Network
Yunjeong Lee, Jongho Park, Do-Young Byun +10
The East Asia VLBI Network (EAVN) has recently enabled dual-polarization observations at and . We present the first systematic verification of its polarimetr…
Where within the 3C 84 jet are -rays produced?
Georgios F. Paraschos, Ioannis Liodakis, Svetlana Jorstad +49
The location of -ray creation and emission within extra-galactic jets is a matter of active debate. One particularly well-suited source to pinpoint the location is the nearby, b…
Magnetic field strength constraints on -ray flaring regions in the flat spectrum radio quasar PKS 1222+216
Yeji Jo, Sang-Sung Lee
We present a multi-wavelength study of the Flat Spectrum Radio Quasar PKS 1222+216, analyzing its long-term variability of radio data obtained in 2013-2020 from the iMOGABA, MOJAVE…