Broad-line type Ic SN 2020bvc: Signatures of an off-axis gamma-ray burst afterglow

L Izzo; K Auchettl; J Hjorth; F De Colle; C Gall; CR Angus; SI Raimundo; E Ramirez-Ruiz

Journal article

Broad-line type Ic SN 2020bvc: Signatures of an off-axis gamma-ray burst afterglow

L Izzo, K Auchettl, J Hjorth, F De Colle, C Gall, CR Angus, SI Raimundo, E Ramirez-Ruiz

Astronomy and Astrophysics | EDP SCIENCES S A | Published : 2020

DOI: 10.1051/0004-6361/202038152

Abstract

Long-duration gamma-ray bursts (GRBs) are almost unequivocally associated with very energetic, broad-line supernovae of Type Ic-BL. While the gamma-ray emission is emitted in narrow jets, the SN emits radiation isotropically. Therefore, it has been hypothesized that some SN Ic-BL not associated with GRBs arise from events with inner engines such as off-axis GRBs or choked jets. Here we present observations of the nearby (d&Rlarr2; =&Rlarr2; 120 Mpc) SN 2020bvc (ASAS-SN 20bs) that support this scenario. Swift-UVOT observations reveal an early decline (up to two days after explosion), while optical spectra classify it as a SN Ic-BL with very high expansion velocities (≈70 000 km s-1), similar ..

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University of Melbourne Researchers

Katie Auchettl Author

Related Projects (1)

ARC CENTRE OF EXCELLENCE FOR ALL SKY ASTROPHYSICS IN 3D (ASTRO 3D)

Grants

Awarded by INAF-Osservatorio Astronomico di Padova

Funding Acknowledgements

We thank the referee for his/her valuable comments, which definitely help to improve the quality of the paper. Based on observations collected at Copernico telescope (Asiago, Italy) of the INAF - Osservatorio Astronomico di Padova. We are grateful to P. Ochner and S. Benetti for allowing and executing the Asiago observations presented in this paper. This work was supported by a VILLUM FONDEN Investigator grant to JH (project number 16599) and by a VILLUM FONDEN Young Investigator grant to CG (project number 25501). KAA and ERR are supported by the Danish National Research Foundation (DNRF132). SIR gratefully acknowledges support from the Independent Research Fund Denmark via grant numbers DFF 4002-00275 and 8021-00130. FDC acknowledges support from UNAM-PAPIIT grant AG100820. Parts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013.