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arXiv · 2302.05924

Orphan optical flare as SOSS emission afterglow, localization in time

V. Lipunov·V. Kornilov·K. Zhirkov·N. Tyurina·E. Gorbovskoy·D. Vlasenko·S. Simakov·V. Topolev·C. Francile·R. Podesta·F. Podesta·D. Svinkin·N. Budnev·O. Gress·P. Balanutsa·A. Kuznetsov·A. Chasovnikov·M. Serra-Ricart·A. Gabovich·E. Minkina·G. Antipov·S. Svertilov·A. Tlatov·V. Senik·Yu. Tselik·Ya. Kechin·V. Yurkov
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Abstract

We report on MASTER optical observations of an afterglow-like optical and X-ray transient AT2021lfa/ZTF21aayokph. We detected the initial steady brightening of the transient at 7{\sigma} confidence level. This allowed us to use smooth optical self-similar emission of GRBs model to constrain the explosion time to better than 14 min as well as to estimate its initial Lorentz factor {\Gamma}0 = 20 +/- 10. Taking into consideration the low {\Gamma}0 and non-detection in gamma-rays, we classify this transient as the first failed GRB afterglow.

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V. Lipunov, V. Kornilov, K. Zhirkov, N. Tyurina, E. Gorbovskoy, D. Vlasenko, S. Simakov, V. Topolev, C. Francile, R. Podesta, F. Podesta, D. Svinkin, N. Budnev, O. Gress, P. Balanutsa, A. Kuznetsov, A. Chasovnikov, M. Serra-Ricart, A. Gabovich, E. Minkina, G. Antipov, S. Svertilov, A. Tlatov, V. Senik, Yu. Tselik, Ya. Kechin, V. Yurkov. 2023-02-12. Orphan optical flare as SOSS emission afterglow, localization in time. https://doi.org/10.1093/mnras/stac1906

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