Astronomers find a brand new way that stars die. Really!

Astounding, astonishing astronomy! So many ways to die! 😊

It appears though, the study is not really about the discovery of a new way of how stars die! So perhaps the popular science article went a bit too far!

"... But recent research has uncovered a remarkable, previously unseen fourth option, a long-hypothesized but elusive phenomenon. ...

While searching for the origins of a long-duration gamma-ray burst (GRB), astronomers using the Gemini South telescope in Chile and other telescopes, found a collision of stars or their remnants in the chaotic and densely packed vicinity surrounding a supermassive black hole within an ancient galaxy.

“These new results show that stars can meet their demise in some of the densest regions of the Universe where they can be driven to collide ..."

"... The general consensus used to be that long gamma ray bursts of at least a few seconds can only occur when a very heavy star collapses into a supernova at the end of its life. In 2022, a second potential trigger of long gamma ray bursts was uncovered when two large stars, which had been orbiting each other all their lives, turned into neutron stars at the end and collided into a kilonova. Now in 2023, it seems that long gamma ray bursts can occur in a third way. ...
“Our data indicate that this is a case of two separate neutron stars merging. So not neutron stars that have been together all their lives,”... “We suspect that the neutron stars were pushed together by the gravity of the many surrounding stars at the centre of the galaxy.” ..."

From the abstract:

"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 T90 = 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."

Astronomers find a brand new way that stars die

First long gamma-ray burst ever observed at centre of ancient galaxy (presumed primary news source) For the first time, an international team of astronomers has observed a long gamma-ray burst near the centre of an ancient galaxy. This is special because these kinds of gamma-ray bursts typically occur when massive stars collapse or when neutron stars circle each other for a long time, and there are no such stars at the centre of ancient galaxies. The team, led by Andrew Levan (Radboud University), are publishing their findings in Nature Astronomy.

A long-duration gamma-ray burst of dynamical origin from the nucleus of an ancient galaxy (no public access)