Astronomers think that after neutron stars merge, the debris creates noticeable and infrared light from the decay of radioactive components like platinum and gold formed in the particles from the merger. This burst of light is called a kilonova. Noticeable light and infrared emission were discovered from GW170817 numerous hours after the gravitational waves.
The neutron star merger likely produced a jet of high-energy particles that was not pointed directly at Earth, describing an initial absence of X-rays seen by Chandra. Given that the end of 2020, the X-rays identified by Chandra have actually remained at an almost constant level. The Chandra image from data taken in December 2020 and January 2021 programs X-ray emission from GW170817 and from the center of its host galaxy, NGC 4993.
A research group studying the Chandra information think this steadying of the X-ray emission originates from a shock– like a sonic boom from an aircraft– as the merger particles responsible for the kilonova strikes gas around GW170817. Material heated by such a shock would glow steadily in X-rays giving a “kilonova afterglow”, like Chandra has actually observed. The artists illustration shows the merger debris responsible for the kilonova in blue surrounded by a shock depicted in orange and red.
There is also an alternative explanation suggesting that the X-rays originate from material falling towards a great void that formed after the neutron stars combined. This product is portrayed by a small disk in the center of the illustration. To avoid a coincidence, it is likely that only one of the 2 choices– the kilonova afterglow or matter falling onto a black hole– is a significant source of the discovered X-rays.
The two blue glowing arcs of material above and listed below the kilonova show where product from the now-faded jet has struck surrounding material.
To compare the 2 descriptions astronomers will keep monitoring GW170817 in X-rays and radio waves. The radio emission is anticipated to get brighter over time and be found again in the next few months or years if it is a kilonova afterglow. If the explanation involves matter falling onto a newly-formed great void, then the X-ray output should stay stable or decrease quickly and no radio emission will be spotted over time.
Scientists just recently revealed a source was identified in new Chandra observations carried out in December 2021. Analysis of that information is continuous. No radio detection has yet been reported.
For more information on this research study see:.
Credit: X-ray: NASA/CXC/Northwestern Univ./ A. Hajela et al.; Illustration: NASA/CXC/M. Weiss.
NASAs Chandra X-ray Observatory continues to study GW170817, a neutron star merger that produced gravitational waves.
Numerous telescopes saw different type of light after the discovery in August 2017, but only Chandra is still making a detection.
Early Chandra information exposed the presence of a narrow jet that has actually decreased and expanded with time.
The current study provides X-ray proof for a shock– similar to a sonic boom from an airplane– in the aftermath of the merger.
A paper describing these results appears in the current problem of The Astrophysical Journal Letters and is readily available online [link] The authors are Aprajita Hajela (Northwestern University), Rafella Marguitti (University of California at Berkeley), Joe Bright (Berkeley), Kate Alexander (Northwestern), Brian Metzger (Columbia University), Vsevovold Nedora (University of Jena, Germany), Adithan Kathirgamarju (Berkeley), Ben Margalit (Berkeley), David Radice (Penn State University), Cristiano Guidorzi (University of Ferrara, Italy), Edo Berger (Center for Astrophysics I Harvard & & Smithsonian (CfA)), Andrew MacFadyen (New York University), Dimitrios Giannios (Purdue University), Ryan Chornock (Berkeley), Ian Heywood (University of Oxford, UK), Lorenzo Sironi (Columbia), Ore Gottlieb (Tel Aviv University, Israel), Deanne Coppjans (Northwestern), Tanmoy Laskar (University of Bath, UK), Yvette Cendes (CfA), Rodolfo Barniol Duran (California State University, Sacramento), Tarraneh Eftekhari (CfA), Wen-fai Fong (Northwestern), Austin McDowell (NYU), Matt Nicholl (University of Birmingham, UK), Zhengtong Xie (University of Southampton, UK), Jonathan Zrake (Clemson University), Sebastiano Bernuzzi (University of Jena), Floor Broekgaarden (CfA), Charlie Kilpatrick (Northwestern), Giacomo Terreran (Northwestern), Ashley Villar (Columbia), Peter Blanchard (Northwestern), Sebastian Gomez (CfA), Griffin Hosseinzadeh (University of Arizona), David Jacob Matthews (Berkeley), and Jillian Rastinejad (Northwestern).
NASAs Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatorys Chandra X-ray Center manages science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
An artists conception highlights the aftermath of a “kilonova,” an effective occasion that takes place when two neutron stars merge. NASAs Chandra X-ray Observatory has actually been gathering data on the kilonova connected with GW170817 considering that shortly after it was first found in gravitational waves by the Laser Interferometry Gravitational-wave Observatory (LIGO) and Virgo on August 17, 2017.
GW170817 was the first– and so far the just– cosmic occasion where both gravitational waves and electromagnetic radiation, or light, were discovered. This mix provides scientists with important details about the physics of neutron star mergers and associated phenomena, utilizing observations at several parts of the electro-magnetic spectrum. Chandra is the only observatory still able to spot light from this extraordinary cosmic collision more than four years after the initial occasion.
The neutron star merger likely produced a jet of high-energy particles that was not pointed straight at Earth, describing a preliminary absence of X-rays seen by Chandra. Since the end of 2020, the X-rays identified by Chandra have actually remained at an almost constant level. The Chandra image from information taken in December 2020 and January 2021 programs X-ray emission from GW170817 and from the center of its host galaxy, NGC 4993.
A research study team studying the Chandra data believe this steadying of the X-ray emission comes from a shock– like a sonic boom from a plane– as the merger particles responsible for the kilonova strikes gas around GW170817. Material heated up by such a shock would radiance progressively in X-rays providing a “kilonova afterglow”, like Chandra has observed.
