Finding the failed supernovae

Apr 04, 2011 By Jon Voisey, Universe Today
Credit: chandra.harvard.edu

When high mass stars end their lives, they explode in monumental supernovae. But, when the most massive of these monsters die, theory has predicted that they may not even reveal as much as a whimper as their massive cores implode. Instead, the implosion occurs so quickly, that the rebound and all photons created during it, are immediately swallowed into the newly formed black hole. Estimates have suggested that as much as 20% of stars that are massive enough to form supernovae collapse directly into a black hole without an explosion. These "failed supernovae" would simply disappear from the sky leaving such predictions seemingly impossible to verify. But a new paper explores the potential for neutrinos, subatomic particles that rarely interact with normal matter, could escape during the collapse, and be detected, heralding the death of a giant.

Presently, only one supernova has been detected by its neutrinos. This was supernova 1987a, a relatively close supernova which occurred in the Large Magellanic Cloud, a satellite galaxy to our own. When this star exploded, the neutrinos escaped the surface of the star and reached detectors on Earth three hours before the shockwave reached the surface, producing a visible brightening. Yet despite the enormity of the eruption, only 24 neutrinos (or more precisely, electron anti-neutrinos), were detected between three detectors.

The further away an event is, the more its neutrinos will be spread out, which in turn, decreases the flux at the detector. With current detectors, the expectation is that they are large enough to detect supernovae events around a rate of 1-3 per century all originating from within the and our satellites. But as with most astronomy, the detection radius can be increased with larger detectors. The current generation uses detectors with masses on the order of kilotons of detecting fluid, but proposed detectors would increase this to megatons, pushing the sphere of detectability to as much as 6.5 million light years, which would include our nearest large neighbor, the Andromeda galaxy. With such enhanced capabilities, detectors would be expected to find neutrino bursts on the order of once per decade.

Assuming the calculations are correct and that 20% of supernova implode directly, this means that such gargantuan detectors could detect 1-2 failed supernovae per century. Fortunately, this is slightly enhanced due to the extra mass of the star, which would make the total energy of the event higher, and while this wouldn’t escape as light, would correspond to an increased neutrino output. Thus, the detection sphere could be pushed out to potentially 13 million lightyears, which would incorporate several galaxies with high rates of star formation and consequently, supernoave.

While this puts the potential for detections of failed supernovae on the radar, a bigger problem remains. Say neutrino detectors record a sudden burst of neutrinos. With typical supernovae, this detection would be quickly followed with the optical detection of a supernova, but with a failed supernova, the followup would be absent. The neutrino burst is the beginning and end of the story, which could not initially positively define such an event as different from other supernovae, such as those that form neutron stars.

To tease out the subtle differences, the team modeled the supernovae to examine the energies and durations involved. When comparing failed supernovae to ones forming neutron stars, they predicted that the failed supernovae neutrino bursts would have shorter durations (~1 second) than ones forming neutron stars (~10 seconds). Additionally, the energy imparted in the collision that makes up the detection would be higher for failed (up to 56 MeV vs 33 MeV). This difference could potentially discriminate between the two types.

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omatumr
1 / 5 (6) Apr 04, 2011
Neutron repulsion probably prevents the formation of black holes ["Neutron Repulsion," The APEIRON Journal, in press (2011), 19 pages}.
http://arxiv.org/...2.1499v1

With kind regards,
Oliver K. Manuel
Ethelred
5 / 5 (4) Apr 05, 2011
Neutron repulsion probably prevents the formation of black
How about this Oliver? You evaded the question when it has been asked so far.

Is this neutron repulsion of yours a long distance force?

Because that is what is needed to stop black holes from forming. AND it should stop neutron stars from forming as well as in mainstream thinking the force that holds them up is Strong Force and the Pauli Exclusion principle.

And for about the umpteenth time the size of a Black Hole increases faster than the mass of a Black Hole so that if you have enough of gas with the density of a water you will get a Black Hole even if there is no singularity.

Black Hole DOES NOT EQUAL a singularity if it is a super massive black hole. Only stellar mass black hole MUST have a singularity.

Ethelred
omatumr
1 / 5 (6) Apr 05, 2011
Neutron repulsion is an empirical fact [1-4] recorded in nuclear rest mass data of every nucleus with two or more neutrons, just as the repulsive force that causes the alpha particle (He-4) to be ejected from the nucleus of U-238.

That repulsive force does not cause the U-238 nucleus to immediately disintegrate. Neutron repulsion does not cause neutron stars to immediately fly apart.

References:

1. "Attraction and repulsion of nucleons: Sources of stellar energy", J. Fusion Energy 19, 93-98 (2001):
www.omatumr.com/a...tnuc.pdf

2. "The sun's origin, composition and source of energy", Lunar and Planetary Science XXIX, 1041 (2001).
www.omatumr.com/lpsc.prn.pdf

3. "Nuclear systematics: III. The source of solar luminosity", J. Radioanal. Nucl. Chem. 252, 3-7 (2002).
www.omatumr.com/a...sym3.pdf

4. "The standard solar model versus experimental observations" Beyond Standard Model Physics, IOP Proc (2003) 307-316.
www.omatumr.com/a...2002.pdf
Ethelred
5 / 5 (5) Apr 05, 2011
That isn't what I asked Oliver. Is it long range?

You keep acting as if it is long range. Yes or no?

None of your papers say diddly about range yet you seem certain that is so. Make it clear.

And not it isn't fact. It's your opinion. The Pauli Exclusion Principle IS fact and it covers the data you have.

But you claim something different. You claim it can stop black holes. This requires it to be different from the PEP so what makes it different and to stop a black hole from forming it must be long range. And even long range it can't stop a super massive black hole from forming UNLESS you know something you are keeping secret.

Ethelred
dumbo
5 / 5 (4) Apr 05, 2011
I would like to hear Oliver specifically respond to Ethelred on this point
omatumr
1 / 5 (5) Apr 05, 2011
I would like to hear Oliver . . . respond:"Dynamic competition between gravitational attraction and neutron repulsion sustains our dynamic universe, the Sun, and life on planet Earth."


Quote from page 11 ["Neutron Repulsion," The APEIRON Journal, in press (2011), 19 pages]
http://arxiv.org/...2.1499v1

Calling some forces "long range" and others "short-range" is arbitrary.

Weak, long-range forces become strong at short distances.

Strong, short-range forces become weak at long distances.

Perhaps that is why it took us so long to recognize that "Dynamic competition between gravitational attraction and neutron repulsion sustains our dynamic universe, the Sun, and life on planet Earth."



Ethelred
5 / 5 (6) Apr 06, 2011
Calling some forces "long range" and others "short-range" is arbitrary.
Evasion.

Weak, long-range forces become strong at short distances.
Evasion.

Strong, short-range forces become weak at long distances.
Evasion.

Gravity is a long range force. EM cancels out over long ranges. Weak force only seems to mean anything in the nucleus. The Strong force is VERY short range.

If you can't manage a ball park figure then you have no idea what you are talking about. You have no numbers about the strength or range of the force. Yet you act as if it is stronger than gravity at long ranges and you just plain ignore the Pauli Exclusion Principle which already covers the data you claims proves some new force. Some new force you can't quantify in any way whatsoever.

Ethelred
omatumr
1.2 / 5 (5) Apr 06, 2011
"There is a principle which is a bar against all information,

which is proof against all arguments, and which cannot fail
to keep a man in everlasting ignorancethat principle is
contempt prior to investigation."
Herbert Spencer, or
William H. Poole ?
vidar_lund
not rated yet Apr 06, 2011
I'm curious, is this concept of dark supernovas an accepted theory? To me it sounds weird that such a massive star would just implode with little to see. Those massive stars tend to shed big layers of gas and are generally really big. Even if the core collapses there should still be plenty of gas outside of the core. This gas should be lighting up like a candle from intense heating of the layers that are close to the black hole. The outer layers would be either blown apart greatly increasing the luminosity or sucked into the black hole creating vast amounts of x-rays. Either way, this should be clearly visible and rather spectacular?
Ethelred
5 / 5 (3) Apr 06, 2011
Very good Oliver. I ask a straight forward question and for the eleventeenth time you respond with a irrelevant quote that can only show you don't know the answer.

Which one of us ignorant Oliver? I who ask questions when I don't know the answer or the person that claims to know the answer and gives platitudes instead.

And since you know that I HAVE read all your stuff and it is YOU that refuse to look at things that run counter to your beliefs that was a pretty mindless quotation.

Just answer the bloody question.

Is your neutron repulsion long range or not?

What makes it different from the Pauli Exclusion Principle which is NOT long range?

Why should we think your idea is better than the PEP when the PEP fits your data table. Or rather your students data table.

Mindless irrelevant quotes will be accepted as evidence of capitulation. Only an actual answer will be considered a sign that you have any scientific principles left.

Ethelred
omatumr
1.5 / 5 (8) Apr 06, 2011
It would be a total waste of space and everyone's time to try to communicate with someone that is absolutely convinced that they already know everything.

Ethelred
5 / 5 (4) Apr 07, 2011
Its a simple question Oliver. Evasion like that strongly implies that you don't have an answer.

I am not the only person here in any case. That non-answer is just another way to avoid dealing with difficult questions.

And it was a lie on top of it. I don't think I know everything. The whole human race doesn't know everything. And one thing no one but you knows is whether you think neutron repulsion is long range or not. It isn't my fault nor the fault of anyone else that you find the question to disturbing to answer.

Lying about me won't make people think you are right. I have warned you before about telling lies about me. Since you did it again I will put one link here to an old post by Barakn. More lies more links to the truth on any thread you do it on.

http://www.physor...704.html

Just answer the bloody question and quit lying to avoid it.

Ethelred
omatumr
1 / 5 (6) Apr 07, 2011
Personal attacks and nonsense criticisms from those who hide their own identity are like members of the Communist Youth League in the old USSR who supported Lysenkoism: A self-sustainable cult-like system of distortions, omissions, and lies designed to support faulty or fraudulent research of "politically correct" pseudo-scientists.

www.softpanorama....sm.shtml
Ethelred
4.4 / 5 (5) Apr 07, 2011
Personal attacks and nonsense criticisms from those who hide their own identity are like members of the Communist Youth League in the old USSR who supported Lysenkoism:
Very well Oliver, you are unwilling to answer and you are unable to stop telling lies about me. This is the second time you have called me a Communist.

You get another link.

http://mominer.ms...hildren/

Pretending I didn't exist as you do frequently was a wiser course of action even it does leave you looking like you have no answer. Of course you don't have an answer to the simple question.

Is Neutron repulsion long range or not?

Instead of answering you told lies after many warnings. You got what I promised for the lies and then you told another. All because you haven't the courage to answer a simple question. That others have asked as well.

Ethelred
omatumr
1 / 5 (3) Apr 09, 2011
As mentioned elsewhere, the observational basis of disagreement . . . .


1. Astronomers use the Sun as a model for distant stars.

2. Astronomers view hundreds of distant stars through telescopes,

3. We used this instrument to obtain detailed information on the Sun:

www.omatumr.com/D...Spec.htm

The data do not fit major parts of the Standard Solar Model:

a.) The Sun's origin
b.) The Sun's composition
c.) The Sun's source of energy
d.) The Sun's influence on Earth's climate

That is the observational basis for the disagreement.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
kaasinees
2.7 / 5 (7) Apr 09, 2011
I bet his defense in court was that Neutron Repulsion was sodomizing his kids.
TheQuietMan
2 / 5 (4) Apr 09, 2011
Black Hole DOES NOT EQUAL a singularity if it is a super massive black hole. Only stellar mass black hole MUST have a singularity.

Ethelred


I question this statement and your attacks. The gentleman omatumr has presented several rebuttals in the form of sources, yet not one comes from you (discounting sarcasm and opinion). Perhaps there is bad blood between you two, but it doesn't belong here.

How can a black hole of any mass not have a singularity? It is one of the core definitions. It doesn't have to be a point, even a torus singularity formed by a spinning black hole is still a singularity.
frajo
5 / 5 (4) Apr 09, 2011
How can a black hole of any mass not have a singularity? It is one of the core definitions. It doesn't have to be a point, even a torus singularity formed by a spinning black hole is still a singularity.
Singularities are mathematical objects, arising out of mathematical modelling. Singularities in a mathematical model are no problem.
But physical "singularities" are a huge problem as they can't exist. In fact they constitute a weak point of GR. Wherever a physical theory can't avoid singularities, the theory is wrong.
Infinite densities, temperatures, frequencies contradict not only human reasoning - it's worse as they contradict QM.
TheQuietMan
5 / 5 (1) Apr 10, 2011
Perhaps, but beyond the event horizon they must exist. It is core to the collapse, and physics as we know it does not exist beyond the event horizon. Unless the math has gone beyond where I believe it has this is still a basic theory.
omatumr
1 / 5 (5) Apr 10, 2011
Physics as we know it does not exist beyond the event horizon.


Cause & Effect (C&E) control physics as we know it.

That is why physics can be used to explain why:

a.) All primordial He was labeled with excess Xe-136 at the birth of the solar system.
www.youtube.com/w...e_Qk-q7M

b.) Light-weight isotopes and s-products are enriched at the top of the photosphere.

www.youtube.com/w...QSSHIe6k

c.) Neutron-rich nuclei have excess mass from neutron repulsion.

www.youtube.com/w...yLYSiPO0

In the above video you will see that every atom in you and me had the aggressive personality of Kali when ejected from the Sun. Those neutrons decayed to hydrogen and were fused into the atoms that comprise us

d.) Psychology suggests that C&E also has dominant control over you and me, but Buddha discovered the one factor we may be able to influence:

"All that we are is the result of what we have thought.
We are formed and molded by our thoughts."

-Twin Verses of Buddha
Ethelred
3.4 / 5 (5) Apr 11, 2011
I question this statement and your attacks.
That's nice.But wrong.

The gentleman omatumr has presented several rebuttals in the form of sources,
False.

One. Oliver is in no way a gentleman. He is a bully, as can be seen if you search out his history at the University he used to teach at, he has called me names and then had With Kind Regards in his signature which is exceedingly hypocritical, and he is convicted sex offender.

Two. The sources are all his or is misinterpretations of other's work, none of whom agree with him. Most never agreed with him and the guy that wrote Sun as a pulsar paper never wrote anything about again. He has never said a thing to support Oliver. Oliver freaked when I pointed this out.

More
Ethelred
3.4 / 5 (5) Apr 11, 2011
yet not one comes from you (discounting sarcasm and opinion).
Nonsense. I have shown Oliver's errors here for as long as he has been spamming the site. Do you know what the Pauli Exclusion Principle is? Oliver doesn't. We know he doesn't because it explains the data he claims is due to 'neutron repulsion'. Not one of the students that did the work has come out and agreed with Oliver on his misinterpretation of their data. I looked. If you can find something like that you will have managed to support Oliver in way he has never managed.

yet not one comes from you (discounting sarcasm and opinion).
The bad blood is all Oliver's. I don't get mad at him. I just ask him questions and he refuses to answer them. Its pretty consistent. I ask he ignores. I ask again and again and again and eventually he tells lies about me so I tell the truth about him. The he goes ballistic. Just like this time.

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Ethelred
2.3 / 5 (3) Apr 11, 2011
How can a black hole of any mass not have a singularity?
Oliver is the one saying there can't be any black holes. I am just pointing out that a singularity is not a requirement. For one, a rotating black hole is less likely to have a singularity. For another the Universe was once thought to be a closed universe which would be a black hole and with no singularity. Only non-rotating stellar mass and quantum black holes should have a singularity, and even those may not. The larger the black hole's mass the lower the density of mass within the Event Horizon can be thus stellar mass black holes can easily be without a singularity.

It is one of the core definitions.
No it isn't. The core definition is that the mass is great enough to stop light from escaping. The larger the mass the lower the density can be and still have an Event Horizon.

More
Ethelred
1 / 5 (1) Apr 11, 2011
It doesn't have to be a point, even a torus singularity formed by a spinning black hole is still a singularity.
That is a contradiction. A torus is NOT a singularity. It has VOLUME thus it is not a singularity.

And then there is the possibility that NO black hole has a singularity IF the Planck Length is the smallest anything can be. This is a conjecture but it seems very likely due to the Uncertainty Principle which should make singularities impossible in our Universe.

It is core to the collapse,
Core collapse is not certain a in rotating black hole or in a supermassive black hole where the density can be much lower.

physics as we know it does not exist beyond the event horizon.
Sure it does. Its the singularity that can't be handled. Again if a Universe is closed that it is a Black Hole. Our universe seems to be open but that is only a recent discovery.

Ethelred
frajo
5 / 5 (1) Apr 11, 2011
Perhaps, but beyond the event horizon they must exist.
As long as you can't do physics beyond the event horizon this is a non-falsifiable, i.e. unscientific statement.
It is core to the collapse, and physics as we know it does not exist beyond the event horizon.
This is a non-falsifiable statement and therefore unscientific. Instead, we simply don't know.
Unless the math has gone beyond where I believe it has this is still a basic theory.
Maths doesn't need to "go beyond" as maths has no problem with the gravitational singularities in GR. Physics has a problem with singularities and anything dealing with physical singularities cannot be considered "basic" (whatever that is supposed to mean).

frajo
not rated yet Apr 11, 2011
It doesn't have to be a point, even a torus singularity formed by a spinning black hole is still a singularity.
That is a contradiction. A torus is NOT a singularity. It has VOLUME thus it is not a singularity.
When talking about Kerr black holes it is customary to use the term "ring singularity".
A ring can be thought of as being a toroid with a generating circle of zero length radius, i.e. a distorted toroid. This distorted toroid has zero volume.
Ethelred
1 / 5 (1) Apr 11, 2011
A ring can be thought of as being a toroid with a generating circle of zero length radius, i.e. a distorted toroid.
OK that makes no sense to me but I will take your word for it that it makes sense to a topologist.

To me if has no radius it isn't a torus as a torus has an inner radius and and outer radius and it really should have a cross sections otherwise I would expect to be called a disc.

Then there is that matter of math vs. physics. Math can have things that don't exist in this Universe and I really do expect that there is a minimum size to things. Thus to me torus would need to have, at least, a inner radius of one Planck length and an out radius of two Planck lengths and a cross section of one PL. And yes again that is conjecture based on the uncertainty principle and the concept of the Universe having some granularity to it.

And I wouldn't be surprised if a rotating black hole could have at its center a torus of those dimensions.

Ethelred

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