TY - JOUR
T1 - A long-duration gamma-ray burst of dynamical origin from the nucleus of an ancient galaxy
AU - Levan, Andrew J.
AU - Malesani, Daniele B.
AU - Gompertz, Benjamin P.
AU - Nugent, Anya E.
AU - Nicholl, Matt
AU - Oates, Samantha R.
AU - Perley, Daniel A.
AU - Rastinejad, Jillian
AU - Metzger, Brian D.
AU - Schulze, Steve
AU - Stanway, Elizabeth R.
AU - Inkenhaag, Anne
AU - Zafar, Tayyaba
AU - Agüí Fernández, J. Feliciano
AU - Chrimes, Ashley A.
AU - Bhirombhakdi, Kornpob
AU - de Ugarte Postigo, Antonio
AU - Fong, Wen-fai
AU - Fruchter, Andrew S.
AU - Fragione, Giacomo
AU - Fynbo, Johan P. U.
AU - Gaspari, Nicola
AU - Heintz, Kasper E.
AU - Hjorth, Jens
AU - Jakobsson, Pall
AU - Jonker, Peter G.
AU - Lamb, Gavin P.
AU - Mandel, Ilya
AU - Mandhai, Soheb
AU - Ravasio, Maria E.
AU - Sollerman, Jesper
AU - Tanvir, Nial R.
PY - 2023/8
Y1 - 2023/8
N2 - The majority of long-duration (>2 s) gamma-ray bursts (GRBs) arise from the collapse of massive stars, with a small proportion created from the merger of compact objects. Most of these systems form via standard stellar evolution pathways. However, a fraction of GRBs may result from dynamical interactions in dense environments. These channels could also contribute substantially to the samples of compact object mergers detected as gravitational wave sources. Here we report the case of GRB 191019A, a long GRB (a duration of T 90 = 64.4 ± 4.5 s), which we pinpoint close (⪅100 pc projected) to the nucleus of an ancient (>1 Gyr old) host galaxy at z = 0.248. The lack of evidence for star formation and deep limits on any supernova emission disfavour a massive star origin. The most likely route for progenitor formation is via dynamical interactions in the dense nucleus of the host. The progenitor, in this case, could be a compact object merger. These may form in dense nuclear clusters or originate in a gaseous disc around the supermassive black hole. Identifying, to the best of our knowledge, a first example of a dynamically produced GRB demonstrates the role that such bursts may have in probing dense environments and constraining dynamical fractions in gravitational wave populations.
AB - The majority of long-duration (>2 s) gamma-ray bursts (GRBs) arise from the collapse of massive stars, with a small proportion created from the merger of compact objects. Most of these systems form via standard stellar evolution pathways. However, a fraction of GRBs may result from dynamical interactions in dense environments. These channels could also contribute substantially to the samples of compact object mergers detected as gravitational wave sources. Here we report the case of GRB 191019A, a long GRB (a duration of T 90 = 64.4 ± 4.5 s), which we pinpoint close (⪅100 pc projected) to the nucleus of an ancient (>1 Gyr old) host galaxy at z = 0.248. The lack of evidence for star formation and deep limits on any supernova emission disfavour a massive star origin. The most likely route for progenitor formation is via dynamical interactions in the dense nucleus of the host. The progenitor, in this case, could be a compact object merger. These may form in dense nuclear clusters or originate in a gaseous disc around the supermassive black hole. Identifying, to the best of our knowledge, a first example of a dynamically produced GRB demonstrates the role that such bursts may have in probing dense environments and constraining dynamical fractions in gravitational wave populations.
UR - http://www.scopus.com/inward/record.url?scp=85162673864&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/arc/CE17010004
UR - http://purl.org/au-research/grants/arc/FT190100574
U2 - 10.1038/s41550-023-01998-8
DO - 10.1038/s41550-023-01998-8
M3 - Article
AN - SCOPUS:85162673864
SN - 2397-3366
VL - 7
SP - 976
EP - 985
JO - Nature Astronomy
JF - Nature Astronomy
IS - 8
ER -