A Hyperlink Between Quick Radio Bursts, Magnetars, and Supernovae?
What causes the weird, extragalactic quick radio bursts we’ve detected during the last decade? A brand new research of an unusually vivid supernova might have discovered the important thing to answering this query. Artist’s impression of a superluminous supernova. A brand new research has discovered radio emission from one in all these stellar explosions, presumably
What causes the weird, extragalactic quick radio bursts we’ve detected during the last decade? A brand new research of an unusually vivid supernova might have discovered the important thing to answering this query.
Artist’s impression of a superluminous supernova. A brand new research has discovered radio emission from one in all these stellar explosions, presumably offering the important thing to understanding the origin of quick radio bursts.
NASA / CXC / M. Weiss
Clues from a Repeating Burst
The host of FRB 121102 is positioned in context on this Gemini picture.
Gemini Observatory / AURA / NSF / NRC
When a mysterious millisecond radio pulse of extragalactic origin — a quick radio burst (FRB) — was not too long ago discovered to repeat, it gave astronomers a uncommon likelihood to search out this supply’s host galaxy. FRB 121102 was remoted to a star-forming, low-metallicity dwarf galaxy situated roughly three billion light-years away, and a dimmer, persistent radio supply was found in the identical area that produced the bursts.
This localization lent assist to 1 principle for the origin of FRB 121102 (and presumably different FRBs): that the bursts are powered by a magnetized neutron star born a long time in the past in a superluminous supernova.
Superluminous supernovae are a kind of stellar explosion at the least ten occasions extra highly effective than customary supernovae. These supernovae might shine further vivid because of the delivery of a neutron star with extraordinarily sturdy magnetic fields — a magnetar — that spins on millisecond timescales, emitting radiation and winds as its magnetic fields decay and additional powering the explosion.
Artist’s impression of a magnetar — a particularly magnetized neutron star — in a younger star cluster.
ESO / L. Calçada
Within the superluminous-supernova rationalization for FRBs, the magnetar born within the stellar explosion might, even a decade later, energy temporary radio bursts. As well as, it will producing a glowing nebula seen to us as a persistent radio supply.
A group of scientists has now sought to check this image by inspecting recognized superluminous supernovae and looking for indicators of co-located persistent or bursting radio sources. In a current publication led by Tarraneh Eftekhari (Harvard-Smithsonian Heart for Astrophysics), they element their first success.
Radio Supply Discovered
Utilizing the Very Massive Array, Eftekhari and collaborators found a persistent radio supply coincident with the superluminous supernova PTF10hgi, an explosion that went off 7.5 years in the past, roughly 1.5 billion light-years away. That is the primary time a radio supply of any type has ever been related to a superluminous supernova, offering an essential hyperlink between these explosions and different phenomena.
Left: Radio continuum map from VLA 6-GHz observations of PTF10hgi. Proper: Close to-ultraviolet picture of the host galaxy of PTF10hgi from Hubble, with radio contours overlaid. The small crimson circle reveals the optical place of PTF10hgi.
Eftekhari et al. 2019
The authors take a look at a wide range of totally different potential origins for the radio emission seen, like star formation exercise, an lively galactic nucleus, and a supernova blast wave. Although none of those eventualities can but be dominated out with certainty, Eftekhari and collaborators present that every of them is extremely unlikely.
As an alternative, the radio emission is extraordinarily harking back to the persistent radio supply related to FRB 121102. The authors present that the entire observations are in step with a magnetar central engine powering a glowing nebula embedded within the supernova ejecta. And whereas a bursting radio supply wasn’t discovered coincident with the supernova, the authors’ observations had been solely 40 minutes lengthy; an extended statement time might but uncover a co-located FRB.
The authors element future observations that ought to be capable to rule out various origins for the radio emission and strengthen the case for a superluminous-supernova-born magnetar as a supply of quick radio bursts. Within the meantime, it’s thrilling to look at because the items of this puzzle begin to come collectively!
“A Radio Supply Coincident with the Superluminous Supernova PTF10hgi: Proof for a Central Engine and an Analog of the Repeating FRB 121102?,” T. Eftekhari et al 2019 ApJL 876 L10. doi:10.3847/2041-8213/ab18a5
This publish initially appeared on AAS Nova, which options analysis highlights from the journals of the American Astronomical Society.