Solving the jet/cocoon riddle of a gravitational wave event

**(Re)solving the jet/cocoon riddle of a gravitational wave event
Artist’s impression of the jet of material launched after the merger of the two neutron stars. Credit: © Katharina Immer (JIVE)

An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars ever observed. With its high sensitivity and excellent performance, the 100-meter radio telescope in Effelsberg played an important role in the observations.

In August 2017, two were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors. Neutron stars are ultra-dense stars, roughly the same mass as the Sun, but similar in size to a city like Cologne. This event is the first and only one of this type that has been observed so far, and it happened in a galaxy 130 million light-years away from Earth, in the constellation of Hydra.

Astronomers observed the event and the subsequent evolution across the entire electromagnetic spectrum, from gamma-rays, X-rays to visible light and radio waves. Two hundred days after the merger, observations combining in Europe, Africa, Asia, Oceania, and North America proved the existence of a jet emerging from this violent collision. These findings are now published in the scientific journal Science by an international team of astronomers, led by Giancarlo Ghirlanda from the Italian National Institute for Astrophysics (INAF).

This neutron star merger represented the first case where it was possible to associate a detection of gravitational waves to an object emitting light. The event has confirmed scientific theories that have been under discussion for tens of years, and the association of neutron star mergers with one of the most powerful explosions in the universe: gamma-ray bursts. After the merger, a huge amount of material was expelled into space, forming a shell around the object. Astronomers have been tracing its evolution at different wavelengths. However, there were still some remaining questions concerning this event that could not be clarified by any previous observations.

**(Re)solving the jet/cocoon riddle of a gravitational wave event
Image of the source obtained from the combination of thirty-three radio telescopes from five continents. The source can be seen in the center of the image as a red spot (false color image made entirely for illustration). Credit: © Giancarlo Ghirlanda/Science

"We expected part of the material to be ejected through a collimated jet, but it was unclear whether this material could successfully pierce through the surrounding shell," explains Ghirlanda. "There were two competing scenarios: In one case, the jet cannot break through the shell, instead generating an expanding bubble around the object. In the other, the jet is successful in penetrating the shell and then propagates further into space," expands Tiziana Venturi (INAF). Only the acquisition of very sensitive radio images with very high resolution would discard one scenario or the other. This required the use of a technique known as very long baseline interferometry (VLBI) that allows astronomers to combine radio telescopes all around the Earth.

The authors of this publication conducted global observations in the direction of the merger on 12 March 2018 using thirty-three radio telescopes from the European VLBI Network (that connects telescopes from Spain, the United Kingdom, The Netherlands, Germany, Italy, Sweden, Poland, Latvia, South Africa, Russia, and China), e-MERLIN in the UK, the Australian Long Baseline Array in Australia and New Zealand, and the Very Long Baseline Array in the USA.

"Our 100-m radio in Effelsberg participated in the observations and was a key element, due to its and excellent performance," says Carolina Casadio, a member of the research team from the Max Planck Institute for Radio Astronomy (MPIfR).

**(Re)solving the jet/cocoon riddle of a gravitational wave event
Artist’s impression of a jet that breaks out of the material ejected by the neutron stars merger. The jet is produced by the black hole, surrounded by a hot disc, which was formed after the merger. Credit: O.S. Salafia, G. Ghirlanda, NASA/CXC/GSFC/B. Williams et al.

The data from all telescopes were sent to JIVE, The Netherlands, where the most advanced processing techniques were used to produce an image with a resolution comparable to resolving a person on the surface of the Moon. In the same analogy, the expanding bubble would appear with an apparent size equivalent to a truck on the Moon, whereas a successful jet would be detected as a much more compact object. "Comparing the theoretical images with the real ones, we find that only a jet could appear sufficiently compact to be compatible with the observed size," explains Om Sharan Salafia from INAF in Italy. The team determined that this jet contained as much energy as produced by all the stars in our galaxy during one year. "And all that energy was contained in a size smaller than one light-year," says Zsolt Paragi, also from JIVE.

"Within Europe we utilize the RadioNet consortium for an efficient use of our members' radio telescopes. The observations described here combine radio observatories all over Europe and world wide. They require a well-coordinated effort of the collaborating observatories and institutions to achieve such exciting results," explains Anton Zensus, Director at MPIfR and coordinator of the RadioNet consortium.

In the coming years, many more of these neutron star binary mergers will be discovered. "The obtained results also suggest that more than 10 percent of all these mergers should exhibit a successful jet," explains Benito Marcote from JIVE. "These types of observations will allow us to unveil the processes that take place during and after some of the most powerful events in the universe," concludes Sándor Frey from the Konkoly Observatory in Hungary.


Explore further

Radio observations confirm superfast jet of material from neutron star merger

More information: G. Ghirlanda el al., "Compact radio emission indicates a structured jet was produced by a binary neutron star merger," Science (2019). science.sciencemag.org/cgi/doi … 1126/science.aau8815
Journal information: Science

Provided by Max Planck Society
Citation: Solving the jet/cocoon riddle of a gravitational wave event (2019, February 22) retrieved 15 July 2019 from https://phys.org/news/2019-02-jetcocoon-riddle-gravitational-event.html
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Feb 22, 2019
They observed a plasmoid making the transition between quiescent and jet ejection. No faerie tales needed.

Feb 22, 2019
They observed a plasmoid making the transition between quiescent and jet ejection. No faerie tales needed.


How does this mechanism relate to the gravitational waves observed by LIGO?

Feb 22, 2019
They observed a plasmoid making the transition between quiescent and jet ejection. No faerie tales needed.


No they did not, you idiot. How the F is a plasmoid creating gravitational waves and r-process nucleosynthesis, you moron? Stick to Velikovsky, you loon.

Feb 22, 2019
How does this mechanism relate to the gravitational waves observed by LIGO?

Pattern matching of a hiccup from 250,000 "models" to achieve a discovery? Yeah, no science involved, no gravitational waves detected. They detected an EM event, not the collisions of dancing leprechauns.

Feb 22, 2019
How does this mechanism relate to the gravitational waves observed by LIGO?

Pattern matching of a hiccup from 250,000 "models" to achieve a discovery? Yeah, no science involved, no gravitational waves detected. They detected an EM event, not the collisions of dancing leprechauns.


Wrong. Read the literature. Also detected by VIRGO. Damn near simultaneously with the EM signature. Which showed evidence of r-process nucleosynthesis. You won't know what that is. Check it out. Matches theory beautifully. Show me any cockwomble predicting GWs and r-process nucleosynthesis from a f***ing plasmoid, you ignorant tool.

Feb 22, 2019
r-process nucleosynthesis from a f***ing plasmoid,

LOL! Scientists using the Z-machine (z-pinch device) and electron beams (such that plasmoids create) are testing theories of r-process nucleosynthesis. More plasma processes...

Feb 22, 2019
Outflows are ubiquitous in astrophysics. Despite different sizes, velocity and amount of transported energy, luminosity and degree of collimation, they have obvious morphological similarities. However, what is important for us, there is the picture of the outflows from everywhere and none of inflows into somewhere. That is an obvious asymmetry.
https://www.acade...and_Jets

Feb 22, 2019
The pretty jets, the trivial sparklers of plasma, EM fields tangling together. All of that spectacle is nothing more than a Cosmic version of an industrial waste site flaring or municipal garbage dump on fire.
Lots of toxic smoke & shooting flames but otherwise irrelevant.
This is GW170817, the aftermath of the merger.

The really interesting, absolute effects are occurring deep inside the conglomerated smash-up.
The revenant of the merged neutron stars.

How do we know?
The gravity waves are signaling chaotic processing.

It will be an interesting series of studies over the centuries to come.
For instance, will this combined mass be sufficient to trigger a Stygian Oubliette? Where there is only Gravity?

The emergent combination may provide clues useful for developing a confirmable Theory of Quantum Gravity?

Feb 23, 2019
"Pattern matching of a hiccup from 250,000 "models" to achieve a discovery? Yeah, no science involved, no gravitational waves detected. They detected an EM event, not the collisions of dancing leprechauns."

There are great doubts about LIGO, enough to have it independently investigated as fraud, in which case some people should be facing jail time.
Is LIGO guilty of Scientific Fraud?
https://www.resea...ic_Fraud

Search LIGO fraud for others.

Feb 23, 2019
"Pattern matching of a hiccup from 250,000 "models" to achieve a discovery? Yeah, no science involved, no gravitational waves detected. They detected an EM event, not the collisions of dancing leprechauns."

There are great doubts about LIGO, enough to have it independently investigated as fraud, in which case some people should be facing jail time.
Is LIGO guilty of Scientific Fraud?
https://www.resea...ic_Fraud

Search LIGO fraud for others.


More cranks. How the f*** are they detecting an EM event? Dickheads. They didn't even know about the EM event until they detected the GWs, and triangulated onto the position of their origin. Which just happens to mimic the predicted signature, including r-process nucleosynthesis, of a neutron star merger. Wow, what a coincidence!
The author on researchgate is obviously a scientifically illiterate tool. As is anyone that believes him. Dime a dozen, these cranks. All tosspots.

Feb 23, 2019
Jonesdumb running his mouth again. What a drooling idiot!

Feb 23, 2019
Jonesdumb running his mouth again. What a drooling idiot!


Sorry, shitforbrains? Show me where I'm wrong, you clueless tosser.

Feb 23, 2019
"Dime a dozen, these cranks. All tosspots."

Ah, the pot calling the kettle black. The whole of present day astrophysics is a crock.

Feb 23, 2019
You may be witnessing a Unicleus Pressure Valve. As I've predicted in the past with my Grand Fission Theory our Universe is essentially in a closed bubble (with-in our 4 dimensions) so when a Black Hole first initializes a Quantum Funneling process it hasn't the strength to create a perfect stream. Do to the pressure of our universe the process will fold back on itself ultimately blasting photons out from the weaker edges of the Unicleus. ;O)-

Feb 23, 2019
"Dime a dozen, these cranks. All tosspots."

Ah, the pot calling the kettle black. The whole of present day astrophysics is a crock.


Really, shitforbrains? Says whom?

Feb 23, 2019
Search LIGO fraud for others

Astrophysics and climate science have been frauds for decades. They should let the Bernie Madoff's of the world out of prison and replace them with the real fraudsters such as Kip Thorne, N. D. Tyson, and Hawking posthumously.

Feb 23, 2019
well solopiss & cant, since you are setting down the law? I don't want to hear your whining when you are prosecuted for making false accusations.
Convicted by a jury of your peers for producing bogus evidence.
Judicially sentenced for your criminally fraudulent activities.

You're both going to look so spiffy in those orange prison bloomers as you pick up trash along the road.

Feb 23, 2019
I don't want to hear your whining when you are prosecuted for making false accusations.

I didn't file a false police report, we can leave that to the lying duplicitous criminal neoliberals. No Jussies here.

Feb 24, 2019
Monkey antigoracle sockpuppet cantdrive, keeps on driving into trees, hence the brain loss comments he babbles on a consistent basis, his mental institution lets him loose on here as his fellow loonies can't take his stupidity anymore.

Feb 24, 2019
I don't want to hear your whining when you are prosecuted for making false accusations.

I didn't file a false police report, we can leave that to the lying duplicitous criminal neoliberals. No Jussies here.


What a tosser.

Feb 24, 2019
@solon
...doubts about LIGO, enough to have it independently investigated as fraud
for starters, you posted a speculative discussion on researchgate only

there is no evidence of any fraud in that link - the only thing your link contains is the circumstantial speculations of individuals
if the speculations had merit, there would have been a very public inquiry, which would have released data publicly (considering the time frame)

secondly, there is no validation of the claim of fraud

lastly, in order for LIGO to be guilty of fraud, there must be an adjudication, as in a judicial finding or judgement

therefore, the link above is speculative at best and defamation at worst, and considering your delusional belief that "The whole of present day astrophysics is a crock", it is most likely the latter due to your need for MS physics to be false and your demonstrable desire to find and spread any false information that you think supports your claims

Feb 24, 2019
@Captain Stumpy,
@solon
doubts about LIGO, enough to have it independently investigated as fraud
for starters, you posted a speculative discussion on researchgate only

there is no evidence of any fraud in that link - the only thing your link contains is the circumstantial speculations of individuals
if the speculations had merit, there would have been a very public inquiry, which would have released data publicly (considering the time frame)

secondly, there is no validation of the claim of fraud

lastly, in order for LIGO to be guilty of fraud, there must be an adjudication, as in a judicial finding or judgement
...
It's a pity you didn't apply that criteria to your own false accusations of "fraud" against me all these years, mate. An apology from you now would go a long way towards repairing the damage you have needlessly caused to your character/reputation all these years, Stumpy. :)

ps: @Solon, its NOT "whole of Astrophysics"; just "BB-biased Cosmology". :)

Feb 24, 2019
@cantdrive.
Astrophysics and climate science have been frauds for decades.
While (some) of astrophysics and (practically all) of cosmology WAS led off the rails for decades by BB-biased interpretations of observations/data etc, the CLIMATE SCIENCE HAS BEEN ON TRACK since CO2 problem was identified (by Russian/Exxon scientists?) and later politicised by vested interests when fossil PROFITS became threatened. But NOW the Climate Science predictions are coming to pass increasingly, such that even OZ's Liberal-National Conservative Govt (and long-time saboteurs of past climate action attempts) are having to admit the dangers; and are now (too little, too late) trying to forge a real climate change/emissions reductions/renewables policy that is no longer sabotaged by climate deniers within their own party.

CD, my advice as a friend in science and humanity: Stick to astrophysics/cosmology discussions and leave AGW discussions alone until you are more informed/objective. :)

Feb 24, 2019
RC;
Despite your proclamations of "fact" and the opinions of your political action committees, AGW alarmism is not science. There is no doubt we need to reduce pollution (not only plant food) on the planet, but knee jerk solutions and taxation schemes based on deceit is not the answer.
The number one reason why it's not relevant is because the biggest factor by far in climate and weather is the Sun, and due to astrophysicists misrepresentation of this connection it renders all the models based on it irrelevant. The predictions have been miserably inaccurate. Contrary to the propaganda rag the NYT, there is still snow! Almost 2 feet of it at 5000ft in Central AZ, most in over 100-years. And yes, I understand it's weather, but weather is the product of the climate.

Feb 24, 2019
@idiot f*ckwad fraudulent lying POS pseudoscience trolling criminal sam fodera the crank
It's a pity you didn't apply that criteria to your own false accusations of "fraud" against me
1- it's not an accusation if its provable, has evidence, and you demonstrate it

2- if you could prove my comments were false, you would have attempted charges or litigation
you haven't, therefore you're a liar

3- 8,600 posts and you still can't prove you posted the 4 fatal flaws, let alone all 8 flaws

reported for lying, fraud and trolling with pseudoscience idiocy

EDIT:
you're going to try to reply
I don't care

I will report any and all future posts that don't include the 4 fatal flaws and links to where they were posted on PO

Feb 25, 2019
@Forum (and for particular attention of @observicist if reading).

Note the hypocritical and 'unhinged' response from @Captain Stumpy:
@idiot f*ckwad fraudulent lying POS pseudoscience trolling criminal sam fodera the crank
It's a pity you didn't apply that criteria to your own false accusations of "fraud" against me
1- it's not an accusation if its provable, has evidence, and you demonstrate it

2- if you could prove my comments were false, you would have attempted charges or litigation
you haven't, therefore you're a liar

3- 8,600 posts and you still can't prove you posted the 4 fatal flaws, let alone all 8 flaws

reported for lying, fraud and trolling with pseudoscience idiocy

EDIT:
you're going to try to reply
I don't care

I will report any and all future posts that don't include the 4 fatal flaws and links to where they were posted on PO
Sad, isn't it, that this 'bad character' does not want to change his character. This poor troll is far gone. Sad.

Feb 25, 2019
@cantdrive.
Despite your proclamations of "fact"
The facts are there for all to see, now, even admitted by the erstwhile deniers who are now realising the dangers/damage/costs to them here in OZ.
and the opinions of your political action committees,
Not "opinions", readily confirmable reality 'on the ground' here in OZ and around the world.
AGW alarmism is not science.
The science/facts are what they are now seen clearly by all despite the GOP/Russian/Fossil troll-factory stooges' stupidities-for-profit on the net.
There is no doubt we need to reduce pollution (not only plant food) on the planet, but knee jerk solutions and taxation schemes based on deceit is not the answer.
Kneejerk solutions are not what has been proposed. That is a false label applied by the paid-for troll-factory meme-stooges.
the biggest factor by far in climate and weather is the Sun,...
No, regardless of 'inputs', it's atmospheric lag effect that determines GLOBAL temp. Ok? :)

Feb 25, 2019
@RealityCheck

says Captain Beelzebub to RC
@idiot f*ckwad fraudulent lying POS pseudoscience trolling criminal sam fodera the crank
It's a pity you didn't apply that criteria to your own false accusations of "fraud" against me
1- it's not an accusation if its

3- 8,600 posts and you still can't prove you posted the 4 fatal flaws, let alone all 8 flaws

reported for lying, fraud and trolling with pseudoscience idiocy

EDIT:
you're going to try to reply
I don't care

I will report any and all future posts that don't include the 4 fatal flaws and links to where they were posted on PO


I have just finished reading some of the phorums from 2014 of you and ol' Beelzebub here going at it the same as he is doing here - all about the 4 fatal flaws in Bicep2
Quite frankly, RC, it's wearing a little thin going on 6 years. doncha think?
Just give the damned fool what he wants, RC and be done with it, OK?
And why the heck would you give the creep your real name?

Feb 25, 2019
RC;
Despite your proclamations of "fact" and the opinions of your political action committees, AGW alarmism is not science. There is no doubt we need to reduce pollution (not only plant food) on the planet, the biggest factor by far in climate and weather is the Sun


Did you drove into a tree again or fell out of the tree this time ? Your own little reality resides only within 1cm of your brain (that space mostly occupied by your tree swinging skill and ability to smell bannanas) The real world is very real and entirely different from your own.


Feb 25, 2019
Wow. The first multimessenger observation of a neutron star merger is the gift that keeps on giving!

Besides predicting where the heavy elements comes from et cetera, it suddenly show us the least massive black hole we know of (at some 3-4 solar masses) and single handed bridge the heretofore unobserved mass gap between ~ 2 solar masses neutron stars and ~ 5 solar masses black holes [ https://ligo.nort...dex.html ].

Feb 25, 2019
Oy. Predictably the thread went to pseudosciences - 'EU' is known pseudoscience, astrophysics (and other sciences mentioned here) are known sciences, do I really need to say: check with say Wikipedia - and trolls, instead of discussing the extremely interesting science here. Opportunity wasted.

This poor troll is far gone. Sad.


Give it a rest. We can all see that the comments you refer to respond to the original troll. Implying by your own comments that you are a troll too. "- Who's on first? - Who is on first!? Et cetera," Fun for those with normal humor but maybe not understandable for trolls.

By the way, I don't like the invective and personal attacks which detract further from the actual argument, but trolls *are* trolling for them and they *do* earn them by displaying sorry [excuses for] human traits. So what do you expect?

Feb 25, 2019
Makes me snort with laughter.
Yes. Snort I say! With laughter!

Reading the weasel excuses from the buncoartist wooloons infesting this site.

"Oh your Honor. Sure I mugged that old lady & stole her purse. But it was for a good cause!
I needed a fix & my pusher only takes cash!"

The idiocravy deludes themselves that falsely accusing researchers, scientists & academics of criminal activities is okay. As long as there are no repercussions for the wooloons despicable behavior.

Totally lacking in any credible knowledge? The crapulous frauds have the effrontery to commit extortion. Demanding that Real Scientists give credence ti pseudo-scientific gibberish.

Or the cult of fakirs will smear the Real Scientist's reputations, both Professionally & before the Public.

Feb 25, 2019
@S_E_U.
I have just finished reading some of the phorums from 2014 of you and ol' Beelzebub here…..Just give the damned fool what he wants, RC and be done with it
Been there, done that, mate, more than once now. But this sad internet stalker and troll keeps lying/trolling regardless.

Hence why I long ago stopped pandering to his insanity/malice, and just point out that he [Captain Stumpy] had plenty of opportunities to READ it all, instead of trolling/insulting while he BOASTED he DID NOT READ my posts while trolling/insulting me.

So CS IGNORED the flaws I mentioned across various discussions with various interlocutors.

Now, I have no time/inclination to 'feed' said troll who, when last I LINKED to a flaw (in a discussion with @imfromcanada, wherein Captain Stumpy was trolling!), CS LIED that "it never happened" because HIS (now infamous) "TL;DR" research "method" didn't find it!

CS is a liar, and incompetent at that; his APOLOGY is all that's required now. :)

Feb 25, 2019
@torbjorn_b_g_larsson.
This poor troll is far gone. Sad.
We can all see that the comments you refer to respond to the original troll. Implying by your own comments that you are a troll too.
No mystery as to whom I was referring with the "this troll" term. It is a well understood English term referring to present subject (troll under discussion, ie, CS). Please sharpen up your English, tbgl, to avoid relying on (misunderstood) semantics to make a (in this case misdirected) personal comment. Thanks. :)
By the way, I don't like the invective and personal attacks which detract further from the actual argument
Glad to hear it, mate!
but trolls *are* trolling for them and they *do* earn them...
BUT....I am not one of these who "troll for" OR "earn" it, since, as my record shows, I encourage objective/polite science/discourse; but what do I get in return for my pains? I AM the one being targeted/lied about by trolls NOT interested in same. And I defend. :)

Feb 25, 2019
ps @torbjorn_b_g_larsson.
Predictably the thread went to pseudosciences - 'EU' is known pseudoscience, astrophysics (and other sciences mentioned here) are known sciences, do I really need to say: check with say Wikipedia - and trolls, instead of discussing the extremely interesting science here. Opportunity wasted.
Couldn't agree with you more on that, mate! :)

But it's NOT just the 'trolls' you object to that are avoiding discussing the extremely interesting science; it's also you (and others whom you approve of) that ALSO avoid doing so. Example: in thread...

https://phys.org/...ion.html

I posted objective known science based observations re source/distribution of CMB having NO need of BB-biased interpretations/explanations. But I've yet to see YOUR equally scientific response to same. Can you now practice what you aspire to from others, and go answer those points/implications involved in the relevant post therein? Thanks. :)

Feb 25, 2019
"..lastly, in order for LIGO to be guilty of fraud, there must be an adjudication, as in a judicial finding or judgement"

Who is to adjudicate? Mainstream scientists? What about someone like Bibhas De?
http://www.bibhas...book.pdf

Anyway, you know my beef Captain. Until someone can prove that the Apollo astronauts were mistaken when they said it was totally black out there from cislunar space, then I'd rather believe the ancient wise ones of the Kabbalah and the "Hidden Light of Creation" than in the presently accepted, unflasifiable pseudo science.

Feb 26, 2019
@solon
Who is to adjudicate?
adjudicate (v): To hear and settle (a case) by judicial procedure
from the early 18th century (in the sense 'award judicially'): from Latin adjudicat- 'awarded judicially', from the verb adjudicare (see adjudge)
Mainstream scientists? What about someone like Bibhas De?
not unless they are judges
you know my beef Captain
yes
conspiracist ideation leading to a lack of literacy in the sciences and a willingness to wholeheartedly accept delusional debunked claims simply because your bias wants them to be true

funny thing is: you claim mainstream science is "unflasifiable pseudo science" while not actually comprehending what pseudoscience really is

MS is falsifiable, yet the eu isn't
if it happened, eu claims they predicted it

problem is - there are absolutely no theories at all, nor are there histories & written proof of the "hypothesis" let alone a theory or prediction
best you have is web pages of speculation

Feb 26, 2019
Back when the altright gang, called "Sad Puppies", were attempting to hijack the Hugo & Nebulae Awards.
The neo-fascist cretins were confronted with the poor quality of writing & many factual errors in the books they were pimping.

From simple geography errors such as confusing the Balkans & the Baltics. To failing to comprehend the difference between "momentum" & "acceleration". A common error was, still is, to exclaim about seeing twinkling stars, when out of an atmosphere.

When confronted as to why such poor quality of product should be rewarded with Awards?

The altright fairytails speaking for the DBA Sad Puppies, publicly, proudly proclaimed:
"That it was better to be ideologically pure than factually correct! That their politically correct dogma was above scientific accuracy!"

If you have a strong enough stomach,? Sort through the flood of e-books. You can tell the right-fascist swill by their repetitious storylines & tedious repeat of ignorant errors.

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