TITLE:   GCN CIRCULAR
NUMBER:  30301
SUBJECT: GRB 210619B: possibility of lensed visible afterglow?
DATE:    21/06/22 13:01:03 GMT
FROM:    Jean-Luc Atteia at IRAP  <jean-luc.atteia@irap.omp.eu>

Based on the fact that GRB 210619B (1) had a bright visible afterglow that remained above magnitude 20 for nearly one day (2), and considering the detection of an intervening system in its optical spectrum (3), we point out the possibility of lensed afterglow emission from this GRB, in the coming weeks or months (4), that could be detectable with moderate size telescopes.


(1) (D'Avanzo et al. GCN 30261 ; Zhao et al. GCN 30264 ; Kawakubo et al. GCNC 30284 ; Levin et al. GCNC 30283 ; Axelsson et al. GCNC 30270 ; Svinkin et al. GCN 30276 ; Poolakkil et al. GCNC 30279).

(2) (Lipunov et al. GCNC 30259; Lipunov et al. GCNC 30262; Jelinek et al. GCNC 30263; Kong et al. GCNC 30265; Pellegrin et al. GCNC 30268; D. Perley GCNC 30271; Zheng et al. GCNC 30273; Blazek et al. GCNC 30274; Kann et al. GCNC 30275; Xin et al. GCNC 30277; Kuin et al. GCNC 30278, Shrestha et al. GCNC 30280; Jelinek et al. GCNC 30281; Kumar et al. GCNC 30286; D'Avanzo et al. GCNC 30288; D'Avanzo et al. GCNC 30289; Cunningham et al. GCNC 30290; Moskvitin et al. GCNC 30291; Romanov GCNC 30292 ; 
Hu et al. GCNC 30293, Zhu et al. GCNC 30294).

(3) de Ugarte Postigo et al. GCNC 30272.

(4) Oguri, M. (2019) Reports on Progress in Physics, 82, 126901.