Neutron-star merger yields new puzzle for astrophysicists

Neutron-star merger yields new puzzle for astrophysicists
This graphic shows the X-ray counterpart to the gravitational wave source GW170817, produced by the merger of two neutron stars. The left image is the sum of observations with NASA's Chandra X-ray Observatory taken in late August and early Sept. 2017, and the right image is the sum of Chandra observations taken in early Dec. 2017. The X-ray counterpart to GW170817 is shown to the upper left of its host galaxy, NGC 4993, located about 130 million light years from Earth. The counterpart has become about four times brighter over three months. GW170817 was first observed on Aug. 17, 2017. Credit: NASA/CXC/McGill/J.Ruan et al.

The afterglow from the distant neutron-star merger detected last August has continued to brighten - much to the surprise of astrophysicists studying the aftermath of the massive collision that took place about 138 million light years away and sent gravitational waves rippling through the universe.

New observations from NASA's orbiting Chandra X-ray Observatory, reported in Astrophysical Journal Letters, indicate that the unleashed by the collision is more complex than scientists initially imagined.

"Usually when we see a short gamma-ray burst, the jet emission generated gets bright for a short time as it smashes into the surrounding medium - then fades as the system stops injecting energy into the outflow," says McGill University astrophysicist Daryl Haggard, whose research group led the new study. "This one is different; it's definitely not a simple, plain-Jane narrow jet."

Cocoon theory

The new data could be explained using more complicated models for the remnants of the neutron star . One possibility: the merger launched a jet that shock-heated the surrounding gaseous debris, creating a hot 'cocoon' around the jet that has glowed in X-rays and radio light for many months.

The X-ray observations jibe with radio-wave data reported last month by another team of scientists, which found that those emissions from the collision also continued to brighten over time.

While radio telescopes were able to monitor the afterglow throughout the fall, X-ray and optical observatories were unable to watch it for around three months, because that point in the sky was too close to the Sun during that period.

"When the source emerged from that blind spot in the sky in early December, our Chandra team jumped at the chance to see what was going on," says John Ruan, a at the McGill Space Institute and lead author of the new paper. "Sure enough, the afterglow turned out to be brighter in the X-ray wavelengths, just as it was in the radio."

Physics puzzle

That unexpected pattern has set off a scramble among astronomers to understand what physics is driving the emission. "This neutron-star merger is unlike anything we've seen before," says Melania Nynka, another McGill postdoctoral researcher. "For astrophysicists, it's a gift that seems to keep on giving." Nynka also co-authored the new paper, along with astronomers from Northwestern University and the University of Leicester.

The neutron-star merger was first detected on Aug. 17 by the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO). The European Virgo detector and some 70 ground- and space-based observatories helped confirm the discovery.

The discovery opened a new era in astronomy. It marked the first time that scientists have been able to observe a cosmic event with both light waves—the basis of traditional astronomy—and , the ripples in space-time predicted a century ago by Albert Einstein's general theory of relativity. Mergers of neutron stars, among the densest objects in the universe, are thought to be responsible for producing heavy elements such as gold, platinum, and silver.


Explore further

Radio observations point to likely explanation for neutron-star merger phenomena

More information: John J. Ruan et al. Brightening X-Ray Emission from GW170817/GRB 170817A: Further Evidence for an Outflow, The Astrophysical Journal (2018). DOI: 10.3847/2041-8213/aaa4f3
Provided by McGill University
Citation: Neutron-star merger yields new puzzle for astrophysicists (2018, January 18) retrieved 16 June 2019 from https://phys.org/news/2018-01-neutron-star-merger-yields-puzzle-astrophysicists.html
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Jan 19, 2018
The rapidly changing field after, during, and just before the collision, will generate a long and large pulse that generates a response to every charge of the affected body. That is, it lights up!

Jan 19, 2018
Or more precisely, different sets and location of un-settling-oscillations that is felt by everyone nearby.

Jan 19, 2018
Clearly they discovered an electromagnetic phenomenon and are blaming it on gravity waves, not surprising coming from the plasma ignoramuses.

Jan 19, 2018
Clearly they discovered an electromagnetic phenomenon and are blaming it on gravity waves, not surprising coming from the plasma ignoramuses.


@CD85:
Did they maybe find one of your magical space batteries that was accidentally overcharged and blew up? Or maybe they discovered one of those outer space circuits that has a short circuit, maybe from the giant space cats chewing on an extension cord. If not those, what EM event did they actually witness at many separate sites?

Jan 20, 2018
Science has added a theory about "the suicide of two neutron stars, when they learned that ISIL fighters committed both murder and suicide." The only difference is that a neutron star can "kill" more than one such innocent victim. today thinks that these are gravitational waves, and they do not know what gravity is and how it arises, these are Aether's oscillations caused by the explosion of the supernova, or the transformation of matter into Aether in black holes, when Aether's oscillation of the whole universe again occurs. j supernova explosion or the formation of BH.

Jan 21, 2018
@CD85:
Did they maybe find one of your magical space batteries that was accidentally overcharged and blew up? Or maybe they discovered one of those outer space circuits that has a short circuit, maybe from the giant space cats chewing on an extension cord. If not those, what EM event did they actually witness at many separate sites?

The morons can't understand that if you have a conductor (plasma for example) moving across a magnetic field (or vice versa) which are everywhere we look, you will have an induction process which creates electric energy. This is your "battery", but even the plasma ignoramuses are catching on to the obvious.

https://youtu.be/fe0jgBqWjKI


Jan 22, 2018
@CD85:
Did they maybe find one of your magical space batteries that was accidentally overcharged and blew up? Or maybe they discovered one of those outer space circuits that has a short circuit, maybe from the giant space cats chewing on an extension cord. If not those, what EM event did they actually witness at many separate sites?

The morons can't understand that if you have a conductor (plasma for example) moving across a magnetic field (or vice versa) which are everywhere we look, you will have an induction process which creates electric energy. This is your "battery", but even the plasma ignoramuses are catching on to the obvious.

https://youtu.be/fe0jgBqWjKI



Lol. An idiotic proposal, that would overturn a whole chunk of science, and it's on.................youtube!
Hahahahaha! Please, do tell us how this woo creates GWs? Probably best if you link to a paper, as I have no doubt that you haven't got a clue what you're talking about.

Jan 22, 2018

The morons can't understand that if you have a conductor (plasma for example) moving across a magnetic field (or vice versa) which are everywhere we look, you will have an induction process which creates electric energy. This is your "battery", but even the plasma ignoramuses are catching on to the obvious.

https://youtu.be/fe0jgBqWjKI



So induction now creates gravitational waves? That's pretty neat. I also like the circle your buddy Dr. Scott created in the first few sentences he spoke in that video:
Source of magnetic fields:
-plasma (electric current in space) generates magnetic field.
-magnetic field interacts with charge carriers (plasma).
-interaction creates an induction mechanism which creates electric currents.

Kinda seems like he claims that electric currents are what creates electric currents. Missing a few parts, eh?

Jan 22, 2018
Kinda seems like he claims that electric currents are what creates electric currents. Missing a few parts, eh?


Scott's lack of knowledge is not surprising - he's an EE (surprise, surprise) and, from what I've seen, he hasn't got a clue about astrophysics, and astronomical objects. Somebody needs to tell him and cd about the Zeeman and Stark effects.

Jan 22, 2018
I would imagine that the breakdown of the neutron material that was (apparently) spewn outwards should be in the process of 1) Neutron vacuum degeneracy, where the neutrons break down releasing the protons/electron pairs that would then 2) have ample chance to grab onto the high number of free neutrons which amounts to low grade fusion.

In that situation, where you have lots of free neutrons, electrons and protons, still held closely due to the local gravity of the neutron mass, then you are going to have continued fusion and likely fission as well as some of these chunks work themselves up the fusion ladder from Hydrogen, and so even lowgrade, widespread thermonuclear explosion could be happening in such case. It is not impossible at all, but I would think that the dropoff in the emission intensity will only be after it goes thru a wide brightening phase that encompasses fusion and fission cycles due to the neutronium decaying unevenly.

Jan 22, 2018
691, ye have some things confused. First, any time ye have 'million degree gas' it is NOT a gas, it is a plasma since no gas can retain it's atomic structure at that temp. Thus we have large numbers of free electrons and protons, they will often be in huge clouds (think of our polar gamma bubbles to our own galaxy) so you have a carrier there, as stars, with their own magnetic fields, pass thru these clouds they do create current as with any time you pass a magnet along a wire you produce measurable current, same principle in effect.

But it is plain that there are full galactic size currents, with their own magnetic fields (Plenty of evidence) in their own interconnecting cocoons of plasma that form strings of galaxies, and even strings of clusters that appear to all be connected by these same magnetic fields, thus there IS current happening there, since it takes current to make magnetic fields (planetary magnetic field formed by molten iron in core).

No magic, just physics

Jan 23, 2018
@Steelwolf:
I am aware of what plasma is, no worries there. If you watch the YouTube video CD85 posted, my summary is what Scott said. Plasma is flowing, therefore has an electric current. This current has an associated magnetic field. This magnetic field interacts with the plasma (this time seen as charges, not an electric current). This interaction generates an induction mechanism which creates an electric current. He made a full circle claiming that the electric current creates an electric current. Watch the video and tell me he didn't say that.
Based on what he did say, I could see why EU folks think plasma is so amazing if you didn't actually understand E&M.

Jan 23, 2018
But it is plain that there are full galactic size currents,.......


Is it? I keep hearing this, but have yet to see the evidence. I searched myself, but got a bunch of results dominated by Peratt's long discredited PU model. Perhaps you could point to the peer reviewed paper where these currents were actually confirmed, rather than proposed. I rather thought COBE, WMAP & Planck had put an end to this line of reasoning.

Jan 23, 2018
^^^^^^Just to be clear, re the above; are we talking about intra-galactic currents, or inter-galactic currents? My query was regarding the latter, as proposed (wrongly, I believe) by Peratt.

Jan 23, 2018
Based on what he did say, I could see why EU folks think plasma is so amazing if you didn't actually understand E&M.

The gentleman making the statements is a retired Professor of Electrical Engineering of 30 years and wrote a text book, I'm fairly certain he has a firm grasp of the 'E&M'...
The ignorance of EM theory and the implications of a Universe pervaded by electrodynamic matter by the plasma ignoramuses is why they can't find 96% of their hypothetical dark universe.

Jan 23, 2018
1) Neutron vacuum degeneracy, where the neutrons break down releasing the protons/electron pairs that would then 2) have ample chance to grab onto the high number of free neutrons
........so what's the length of time of this "ample chance"?


Jan 23, 2018
Based on what he did say, I could see why EU folks think plasma is so amazing if you didn't actually understand E&M.

The gentleman making the statements is a retired Professor of Electrical Engineering of 30 years and wrote a text book, I'm fairly certain he has a firm grasp of the 'E&M'...
The ignorance of EM theory and the implications of a Universe pervaded by electrodynamic matter by the plasma ignoramuses is why they can't find 96% of their hypothetical dark universe.


Where's the paper, woo boy?

Jan 23, 2018
1) Neutron vacuum degeneracy, where the neutrons break down releasing the protons/electron pairs that would then 2) have ample chance to grab onto the high number of free neutrons
........so what's the length of time of this "ample chance"?



Don't be dense. Jesus, this has already been pointed out you, you burke. Try to learn. A vain hope, I do realise. LOOK UP 'NEUTRON DEGENERACY PRESSURE'. How many frigging times? Idiot.

Jan 23, 2018
The gentleman making the statements is a retired Professor of Electrical Engineering of 30 years and wrote a text book, I'm fairly certain he has a firm grasp of the 'E&M'...


The idiot making the statement hasn't got the foggiest clue about either plasma physics or astrophysics. See his 'electric sun' idiocy, if you don't believe me. He is a waster, of no account. Nobody has either heard of him, nor takes the plank seriously. He is a nobody.


Jan 23, 2018
The gentleman is a retired Professor of Electrical Engineering of 30 years and wrote a text book, I'm fairly certain he has a firm grasp of the 'E&M'


The idiot making the statement hasn't got the foggiest clue about either plasma physics or astrophysics. See his 'electric sun' idiocy, if you don't believe me. He is a waster, of no account. Nobody has either heard of him, nor takes the plank seriously. He is a nobody.


Coming from someone who has this manner of explanation of HIS background in Differential Equations that he now claims he took in High School Algebra class:

Jesus H. Christ! Where were you 'educated'? Differential equations were covered in 6th form maths in NZ decades ago. That is, for kids who were 16-17 years old! Well done for figuring it out in your 20s. Have a word with your local education authorities. Might be a bit behind the rest of us.


You wouldn't recognize a Differential Eq slapping you up alongside your head.


Jan 23, 2018
Large scale electric currents;

https://youtu.be/r0qZiI6oH2I

Recall the scalability of plasma phenomena. Inter/intra, doesn't matter because it is all plasma and similar properties apply. Entire clusters of galaxies reside within Birkeland currents, the flow toward 'The Great Attractor' is evidence of this. This is far beyond the relevance of gravity at this scale.

Jan 23, 2018
Just as a reminder, @Lennitheliar:
-m'' + m'n' - m'² - 2m'/r = 0
m'' + m'² - m'n' - 2m'/r = 0
e⁻²ⁿ (1 + m'r - n'r) - 1 = 0
R₂₂ sin² ϕ = 0
Source: http://www.etsu.e...esis.pdf
And another reminder:
E² = (pc)² + (mc²)²
https://phys.org/...rgy.html
https://phys.org/...ole.html

Jan 24, 2018
Just as a reminder, @Lennitheliar:
-m'' + m'n' - m'² - 2m'/r = 0
m'' + m'² - m'n' - 2m'/r = 0
e⁻²ⁿ (1 + m'r - n'r) - 1 = 0
R₂₂ sin² ÄĹ�Ä�ď��ď�� = 0
Source: http://www.etsu.e...esis.pdf

..........another overage Trekkie who doesn't know how to solve Differential Equations, or like his cyber brother jonesy wouldn't even recognize what one looks like.

Hey schneibo, did you also take Differential Equations in High School algebra class? (be careful, this could be a trick question)

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