Acknowledgement
We are grateful to the staff of the KVN, who helped us to operate the array and to correlate the data. The KVN is a facility operated by KASI (Korea Astronomy and Space Science Institute). The KVN observations and correlations are supported through high-speed network connections among the KVN sites provided by KREONET (Korea Research Environment Open NETwork), which is managed and operated by KISTI (Korea Institute of Science and Technology Information). This work has made use of Fermi-LAT data supplied by Abdollahi et al. (2023), https://fermi.gsfc.nasa.gov/ssc/data/access/lat/LightCurveRepository. This work was supported by a grant from the National Research Foundation of Korea (NRF) funded by the Korean government (MIST) (2020R1A2C2009003).
References
- Abdo, A. A., Ackermann, M., Ajello, M., et al. 2010, ApJ, 710, 1271
- Abdollahi, S., Ajello, M., Baldini, L., et al. 2023, ApJS, 265, 31
- Algaba, J. C., Nakamura, M., Asada, K., & Lee, S. S. 2017, ApJ, 834, 65
- Algaba, J.-C., Zhao, G.-Y., Lee, S.-S., et al. 2015, JKAS, 48, 237
- Algaba, J.-C., Lee, S.-S., Rani, B., et al. 2018, ApJ, 859, 128
- Angel, J. R. P., & Stockman, H. S. 1980, ARA&A, 18, 321
- Atwood, W. B., Abdo, A. A., Ackermann, M., et al. 2009, ApJ, 697, 1071
- Blandford, R., Meier, D., & Readhead, A. 2019, ARA&A, 57, 467
- Burrows, D. N., Hill, J. E., Nousek, J. A., et al. 2005, Space Sci. Rev., 120, 165 https://doi.org/10.1007/s11214-005-5097-2
- Carroll, B. W., & Ostlie, D. A. 2017, An introduction to modern astrophysics, 2nd edn. (Cambridge: Cambridge University Press)
- Chidiac, C., Rani, B., Krichbaum, T. P., et al. 2016, A&A, 590, A61
- Das, A. K., Prince, R., & Gupta, N. 2021, ApJ, 920, 117
- de Witt, A., Jacobs, C. S., Gordon, D., et al. 2023, AJ, 165, 139
- Deller, A. T., Brisken, W. F., Phillips, C. J., et al. 2011, PASP, 123, 275
- Drake, A. J., Djorgovski, S. G., Mahabal, A., et al. 2009, ApJ, 696, 870
- Event Horizon Telescope Collaboration, Akiyama, K., Alberdi, A., et al. 2019, ApJ, 875, L4
- Fey, A. L., Ma, C., Arias, E. F., et al. 2004, AJ, 127, 3587
- Gehrels, N., Chincarini, G., Giommi, P., et al. 2004, ApJ, 611, 1005
- Hodgson, J. A., Lee, S.-S., Zhao, G.-Y., et al. 2016, JKAS, 49, 137
- Homan, D. C., Cohen, M. H., Hovatta, T., et al. 2021, ApJ, 923, 67
- Jorstad, S. G., Marscher, A. P., Morozova, D. A., et al. 2017, ApJ, 846, 98
- Kang, S., Lee, S. S., Hodgson, J., et al. 2021, A&A, 651, A74
- Kataoka, J., & Stawarz, L. 2005, ApJ, 622, 797
- Kellermann, K. I., Lister, M. L., Homan, D. C., et al. 2004, ApJ, 609, 539
- Lee, J. W., Lee, S.-S., Hodgson, J. A., et al. 2017, ApJ, 841, 119
- Lee, J. W., Lee, S.-S., Algaba, J.-C., et al. 2020, ApJ, 902, 104
- Lee, S.-S., Oh, C. S., Roh, D.-G., et al. 2015, JKAS, 48, 125
- Lee, S.-S., Wajima, K., Algaba, J.-C., et al. 2016, ApJS, 227, 8
- Lobanov, A. P., Krichbaum, T. P., Witzel, A., & Zensus, J. A. 2006, PASJ, 58, 253
- Marscher, A. P. 1977, ApJ, 216, 244
- Marscher, A. P. 1983, ApJ, 264, 296
- Marti-Vidal, I., Krichbaum, T. P., Marscher, A., et al. 2012, A&A, 542, A107
- Niinuma, K., Lee, S.-S., Kino, M., et al. 2014, PASJ, 66, 103
- Padovani, P., Alexander, D. M., Assef, R. J., et al. 2017, A&A Rev., 25, 2
- Richards, J. L., Max-Moerbeck, W., Pavlidou, V., et al. 2011, ApJS, 194, 29
- Roming, P. W. A., Kennedy, T. E., Mason, K. O., et al. 2005, Space Sci. Rev., 120, 95
- Scargle, J. D., Norris, J. P., Jackson, B., & Chiang, J. 2013, ApJ, 764, 167 https://doi.org/10.1088/0004-637X/764/2/167
- Shaw, M. S., Romani, R. W., Cotter, G., et al. 2012, ApJ, 748, 49
- Shepherd, M. C., Pearson, T. J., & Taylor, G. B. 1994, in Bull. Am. Astron. Soc., Vol. 26, 987-989
- Smith, P. S., Montiel, E., Rightley, S., et al. 2009, arXiv e-prints, arXiv:0912.3621
- Urry, C. M., & Padovani, P. 1995, PASP, 107, 803
- Wells, D. C. 1985, in Data Analysis in Astronomy, ed. V. di Gesu, L. Scarsi, P. Crane, J. H. Friedman, & S. Levialdi, 195
- Whitney, A. R. 2002, in Proc. of the 6th EVN Symp., 41
- Zargaryan, D., Mackey, J., Barnouin, T., & Aharonian, F. 2022, MNRAS, 510, 1118