TITLE: GCN CIRCULAR NUMBER: 25581 SUBJECT: GRB 190829A: Follow up VLA and VLBI radio observations urged DATE: 19/08/30 20:21:02 GMT FROM: Arnon Dar at Technion-Israel Inst. of Tech S. Dado and A. Dar report, The long duration, low luminosity GRB190829A [1] at redshift z=0.0785 [2] with Ep=130 +/- 20 keV and Eiso~1.8E50 erg, most probably, is an ordinary narrowly beamed GRB being viewed from far off-axis -it satisfies well the correlation (1+z)Ep propto (Eiso)^{1/3}, predicted [3] by the cannonball model of GRBs, as can be seen from figure 3 of [4]. Like in SHB 170817A [5], VLA and VLBI follow up observations of the radio afterglow of GRB190829A may resolve its compact superluminal source and measure its apparent superluminal velocity, Vapp ~ 2c/theta, from which its far off-axis viewing angle theta can be determined [6]. We urge such follow up VLA and VLBI radio observations of its afterglow. [1] S. Lesage et al., GCN 25575. [2] A. F. Valeev et al., GCN 25565. [3] A. Dar & A. De R'ujula, arXiv:astro-ph/0012227 (Eq. 40). [4] S. Dado & A. Dar, arxiv:1908.05116. [5] K. P. Mooley, et al., Nature, 561, 355 (2018) [arXiv:1806.09693]. [6] A. Dar & A. De R'ujula, arXiv:astro-ph/0008474.