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Title: Interferometric Monitoring of Gamma-Ray Bright AGNs: S5 0716+714

Abstract

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 129 GHz bands, as part of the Interferometric Monitoring of Gamma-ray Bright active galactic nuclei (iMOGABA) KVN key science program. Observations were conducted in 29 sessions from 2013 January 16 to 2016 March 1, with the source being detected and imaged at all available frequencies. In all epochs, the source was compact on the milliarcsecond scale, yielding a compact VLBI core dominating the synchrotron emission on these scales. Based on the multiwavelength data between 15 GHz (Owens Valley Radio Observatory) and 230 GHz (Submillimeter Array), we found that the source shows multiple prominent enhancements of the flux density at the centimeter (cm) and millimeter (mm) wavelengths, with mm enhancements leading cm enhancements by −16 ± 8 days. The turnover frequency was found to vary between 21 and 69 GHz during our observations. By assuming a synchrotron self-absorption model for the relativistic jet emission in S5 0716+714, we found the magnetic field strength in the mas emission region to be ≤5 mG during the observing period, yielding a weighted mean of 1.0more » ± 0.6 mG for higher turnover frequencies (e.g., >45 GHz).« less

Authors:
; ; ; ; ;  [1];  [2];  [3]
  1. Korea Astronomy and Space Science Institute, 776 Daedeok-daero, Yuseong-gu, Daejeon 34055 (Korea, Republic of)
  2. Department of Physics and Astronomy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826 (Korea, Republic of)
  3. Department of Astronomy and Space Science, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do 17104 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22663550
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 841; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BL LACERTAE OBJECTS; COMPACTS; COSMIC GAMMA BURSTS; EMISSION; FLUX DENSITY; GALAXIES; GALAXY NUCLEI; GAMMA RADIATION; GHZ RANGE; INTERFEROMETRY; LINEAR ABSORPTION MODELS; MAGNETIC FIELDS; RELATIVISTIC RANGE; SELF-ABSORPTION; SYNCHROTRON RADIATION; WAVELENGTHS

Citation Formats

Lee, Jee Won, Lee, Sang-Sung, Hodgson, Jeffrey A., Algaba, Juan-Carlos, Kang, Sincheol, Kang, Jiman, Kim, Dae-Won, and Kim, Sungsoo S., E-mail: sslee@kasi.re.kr. Interferometric Monitoring of Gamma-Ray Bright AGNs: S5 0716+714. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA72F7.
Lee, Jee Won, Lee, Sang-Sung, Hodgson, Jeffrey A., Algaba, Juan-Carlos, Kang, Sincheol, Kang, Jiman, Kim, Dae-Won, & Kim, Sungsoo S., E-mail: sslee@kasi.re.kr. Interferometric Monitoring of Gamma-Ray Bright AGNs: S5 0716+714. United States. doi:10.3847/1538-4357/AA72F7.
Lee, Jee Won, Lee, Sang-Sung, Hodgson, Jeffrey A., Algaba, Juan-Carlos, Kang, Sincheol, Kang, Jiman, Kim, Dae-Won, and Kim, Sungsoo S., E-mail: sslee@kasi.re.kr. Thu . "Interferometric Monitoring of Gamma-Ray Bright AGNs: S5 0716+714". United States. doi:10.3847/1538-4357/AA72F7.
@article{osti_22663550,
title = {Interferometric Monitoring of Gamma-Ray Bright AGNs: S5 0716+714},
author = {Lee, Jee Won and Lee, Sang-Sung and Hodgson, Jeffrey A. and Algaba, Juan-Carlos and Kang, Sincheol and Kang, Jiman and Kim, Dae-Won and Kim, Sungsoo S., E-mail: sslee@kasi.re.kr},
abstractNote = {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 129 GHz bands, as part of the Interferometric Monitoring of Gamma-ray Bright active galactic nuclei (iMOGABA) KVN key science program. Observations were conducted in 29 sessions from 2013 January 16 to 2016 March 1, with the source being detected and imaged at all available frequencies. In all epochs, the source was compact on the milliarcsecond scale, yielding a compact VLBI core dominating the synchrotron emission on these scales. Based on the multiwavelength data between 15 GHz (Owens Valley Radio Observatory) and 230 GHz (Submillimeter Array), we found that the source shows multiple prominent enhancements of the flux density at the centimeter (cm) and millimeter (mm) wavelengths, with mm enhancements leading cm enhancements by −16 ± 8 days. The turnover frequency was found to vary between 21 and 69 GHz during our observations. By assuming a synchrotron self-absorption model for the relativistic jet emission in S5 0716+714, we found the magnetic field strength in the mas emission region to be ≤5 mG during the observing period, yielding a weighted mean of 1.0 ± 0.6 mG for higher turnover frequencies (e.g., >45 GHz).},
doi = {10.3847/1538-4357/AA72F7},
journal = {Astrophysical Journal},
number = 2,
volume = 841,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}