Bound neutrons pave way to free ones

Feb 07, 2011
Some experiments seem to show that the building blocks of protons and neutrons inside a nucleus are somehow different from that of free ones (the EMC Effect). Other experiments show they behave differently when they pair up (Short-Range Correlations): they move faster and frequently overlap. Combining the data from experiments addressing these two effects, nuclear physicists showed that the two were connected. This connection has allowed scientists, for the first time, to extract information through experimentation about the internal structure of free neutrons, without the assistance of a theoretical model. Credit: DOE's Jefferson Lab

(PhysOrg.com) -- A study of bound protons and neutrons conducted at the Department of Energy's Thomas Jefferson National Accelerator Facility has allowed scientists, for the first time, to extract information through experimentation about the internal structure of free neutrons, without the assistance of a theoretical model. The result was published in the Feb. 4 issue of Physical Review Letters.

The major hurdle for scientists who study the internal structure of the neutron is that most are bound up inside the nucleus of atoms to protons. In nature, a free neutron lasts for only a few minutes, while in the nucleus, neutrons are always encumbered by the ubiquitous proton.

To tease out a description of a free neutron, a group of scientists compared data collected at Jefferson Lab and the SLAC National Accelerator Laboratory that detail how bound protons and neutrons in the nucleus of the atom display two very different effects. Both and neutrons are referred to as nucleons.

"Both effects are due to the nucleons behaving like they are not free," says Doug Higinbotham, a Jefferson Lab staff scientist.

Nucleons appear to differ when they are tightly bound in heavier nuclei versus when they are loosely bound in light nuclei. In the first effect, experiments have shown that nucleons tightly bound in a heavy nucleus pair up more often than those loosely bound in a light nucleus.

"The first thing was the probability of finding two nucleons close together in the nucleus, what we call a short-range correlation," says Larry Weinstein, a professor at Old Dominion University. "And the probability that the two nucleons are in a short-range correlation increases as the nucleus gets heavier."

Meanwhile, other experiments have shown a clear difference in how the proton's building blocks, called quarks, are distributed in heavy nuclei versus light nuclei. This difference is called the EMC Effect.

"People were measuring and discussing the EMC effect. And people were discussing things about the short-range correlations effect. Nobody bothered to look to see if there's any connection between them," adds Eliezer Piasetzky, a professor at Tel Aviv University in Israel.

When the group combined the data from a half-dozen experiments regarding these two different effects on one graph, they found that the two effects were correlated.

"Take a quantity that tells you how strong the EMC Effect is. And then take another quantity that tells you how many short-range correlations you have," Higinbotham explains. "And you see that when one is big, the other one is big. When one is small, the other one is small."

The scientists say that it's unlikely that one effect causes the other. Rather, the data shows that there is a common cause for both.

"I think that we certainly agree that from the position picture, it's due to nucleons overlapping that is causing this. And in the momentum picture, it is the high-momentum nucleons that are causing this. And, of course, it's quantum mechanics, so choose your picture," Higinbotham explains.

The group says the common cause may have remained a mystery for so long, because while the two effects they are studying are obviously related when laid out on a graph, the connection was previously obscured by the different, yet related ways in which the two effects are studied.

"When you do a measurement for the EMC Effect, what you do is you look inside the nucleon. You break open the nucleon and see inside. What happens inside the nucleon is very different from the short-range correlations, which is what happens between two different nucleons," Piasetzky says.

"What's very new here is that we have linked two fields that were completely disconnected. So now you can start asking questions about what that connection can help us learn," Higinbotham says.

They say the next step is to further compare the data from all of the source experiments that they used in their analysis to see if data for one effect may now be used to learn something new about the other. Then, of course, they'd like to use the knowledge that the two effects are connected to design new experiments for shining a light on other secrets buried in the nucleus of the atom.

Explore further: New microscope collects dynamic images of the molecules that animate life

More information: link.aps.org/doi/10.1103/PhysRevLett.106.052301

Provided by Thomas Jefferson National Accelerator Facility

4.9 /5 (54 votes)

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tpb
1 / 5 (5) Feb 07, 2011
Quote,
In nature, a free neutron lasts for only a few minutes.

If true, what is a neutron star, and how does it exist without protons.
eachus
5 / 5 (8) Feb 07, 2011
If true, what is a neutron star, and how does it exist without protons.


The neutrons in a neutron star are not free, so that is not an issue. At the surface, there is a thin layer of ordinary matter that contains plenty of protons. When it gets too thick, you get a nova. When the neutron star adds two much weight, it becomes a supernova.
PPihkala
5 / 5 (7) Feb 07, 2011
Quote,
In nature, a free neutron lasts for only a few minutes.

If true, what is a neutron star, and how does it exist without protons.

Neutron star is not formed by one neutron. In neutron stars there are massive amount of nucleus parts compressed together, so there are no free neutrons there. Therefore they are stable. Look at Wikipedia for more info.
Question
1 / 5 (11) Feb 07, 2011
One theory is that our sun was once a supernova.
If so, it was a neutron star and neutrons on the surface being unbound would slowly decay. A neutron decays into a proton and electron plus neutrino radiation. The proton and electron would combine to form hydrogen which could at least in theory turn a neutron star into a sun again given enough time.

Skeptic_Heretic
4.2 / 5 (14) Feb 07, 2011
One theory is that our sun was once a supernova.
No, that's a shitty hypothesis (from a fellow physorg poster) that has been disproved by just about every observation of stellar evolution known.

Stop throwing the word theory around if you don't know what it means within the realm of science.
axemaster
4.6 / 5 (10) Feb 07, 2011
One theory is that our sun was once a supernova.
If so, it was a neutron star and neutrons on the surface being unbound would slowly decay. A neutron decays into a proton and electron plus neutrino radiation. The proton and electron would combine to form hydrogen which could at least in theory turn a neutron star into a sun again given enough time.


Wha... Whaaaaaatttt?????

The things people will believe/parrot...
Resonance
5 / 5 (2) Feb 07, 2011
Supernovas are not completely made of neutrons however the ratio n/p is very large. A normal nucleus with a such a high ratio would be very unstable.
It turns out that gravity is responsible for neutron star stability. Recall the neutron is slightly more massive than the proton; and under such high gravitational energy, it becomes more energetically favorable to occupy more massive states.
This is the reasoning why people have developed quark star models which predict exotic matter in the cores of these stars.
However, we don't have a neutron star equation of state, and we will never be able to probe the insides of the neutron star. So a methodology to prove any of these models is still far away.
ekim
5 / 5 (3) Feb 07, 2011
However, we don't have a neutron star equation of state, and we will never be able to probe the insides of the neutron star. So a methodology to prove any of these models is still far away.

Neutrinos should be able to probe a neutron star. The star itself might emit electron antineutrinos when neutrons decay into protons. Also an artificial or natural source of neutrinos, on the opposite side of a neutron star, could reveal the inner workings of the star. Either way, never say never.
Question
1 / 5 (11) Feb 08, 2011
One theory is that our sun was once a supernova.
No, that's a shitty hypothesis (from a fellow physorg poster) that has been disproved by just about every observation of stellar evolution known.

Stop throwing the word theory around if you don't know what it means within the realm of science.

And what is the present theory, all the heavy metals "just happened to be in the neighborhood when the sun formed?" Now that is dreaming.
Skeptic_Heretic
5 / 5 (10) Feb 08, 2011
And what is the present theory, all the heavy metals "just happened to be in the neighborhood when the sun formed?" Now that is dreaming.
No, that's stellar evolution, which is an actual theory as we have been watching it happen over and over and over in space.
Nik_2213
5 / 5 (9) Feb 08, 2011
"...our sun was once a supernova."
Nearly, but not quite: A lot of the material that formed our sun and its solar nebula was made in a supernova which seeded and probably compressed a Hydrogen / Helium cloud with its blast. For example, the radioactive isotope Al-26 is only formed and ejected by core-collapse supernovae. Also, IIRC, all the 'Uranics' had similar origins...
Question
1 / 5 (11) Feb 08, 2011
SH:
You got some problems with the stellar model for one where is the evidence for all the heavy metals in star forming regions?
Secondly, why wouldn't all the heavy metal end up in the sun (center) during the convalescing stage?
A supernova origin for our sun can explain all this in a logical sequence?
Gawad
5 / 5 (7) Feb 09, 2011
Question, as Nik above wrote, yes the metals in our solar system do have their origins in a supernova, but the neutron star (or BH) that was formed in that event has long gone on its merry way. Heck, stellar fusion will only get you as far as iron on the periodic table, so anything heavier than that can *only* be created in a supernova explosion afaik.

Neutron stars are not recyclable, much less black holes, despite what some other pysorg poster would have you believe. That stuff has as much a solid foundation as Aether Theory.
Ethelred
5 / 5 (8) Feb 10, 2011
That stuff has as much a solid foundation as Aether Theory.
No. Its worse.

It may be possible to come up with something that resembles an aether theory that might not be a complete crock. There is NO WAY to do that with Oliver's idiotic idea. He is actually claiming that the Sun is a perpetual motion machine. And that is the good part. After all if Crank wants to keep Cranking without an additional input of Nonsense-Energy the Crank must have a Perpetual Cranking Machine fueled by Bovine Fertilizer, loaded by Maxwell's Demon with comments by Eliza.

No, I haven't had enough sleep lately. Why do you ask?

Ethelred
Skeptic_Heretic
5 / 5 (7) Feb 10, 2011
SH:You got some problems with the stellar model for one where is the evidence for all the heavy metals in star forming regions?
When a big star blows up it hurls it's material into space. The msot energetic ejections occur during core collapse supernovae, and the heavier elements you're speaking of are only created under the most extreme of circumstances. Large clusters of mostly hydrogen gas that you're referring to certainly do have a relative abundance of heavy metals if they are the result of such interactions. I don't think you understand what the proportion of heavy to light elements should look like.
Secondly, why wouldn't all the heavy metal end up in the sun (center) during the convalescing stage?
Why would they? Different molecules, with different velocities and trajectories will result in scattering. If you notice, most solar systems discovered thus far have their rocky planets closer than their gas planets.
Question
1 / 5 (10) Feb 10, 2011
There is still not a good explanation as to how so much heavy metal escaped from the center of the sun during its convalescing stage.
If the sun started out as giant star that exploded into a supernova it can be explained quite well, including the angular momentum in the heavy metals needed to orbit the remaining neutron star. It also explains the layers of heavy to lighter elements the further one goes from the center of the explosion.
As for Oliver's explanation of the origin of the sun's energy, I do not accept that either, but the source of that energy can be explained.
After the supernova a neutron star would be remaining. Now the question is what happens to a neutron star? The surface neutrons should slowly decay into hydrogen atoms. After enough hydrogen gas collects on the surface of a neutron star, it should start fusing again warming the convalescing planets.
Skeptic_Heretic
5 / 5 (6) Feb 10, 2011
There is still not a good explanation as to how so much heavy metal escaped from the center of the sun during its convalescing stage.
Ok, well now you're being intentionally dense. The heavy elements are not focused at the center of a supernova. They are thrown outwards, meaning that they are not necessarily in the center. Second, the precursor star to our solar system WAS NOT currently in the position that our sun is in.
After the supernova a neutron star would be remaining. Now the question is what happens to a neutron star? The surface neutrons should slowly decay into hydrogen atoms.
According to who?
After enough hydrogen gas collects on the surface of a neutron star, it should start fusing again warming the convalescing planets.
HYDROGEN GAS CANNOT ACCUMULATE ON THE SURFACE OF A NEUTRON STAR IN THAT MANNER.

Seriously, how are you this stupid?
Ethelred
5 / 5 (7) Feb 10, 2011
not a good explanation as to how so much heavy metal escaped from the center of the sun during its convalescing stage
Orbiting particles are not separated by mass because the velocity of the orbits is dependent on distance and independent of mass.
If the sun started out as giant star that exploded into a supernova it can be explained quite well
No. It would either collapse into a Black Hole or a REALLY hot neutron star that would stay hot billions of years. Neutron stars have a minimum mass that is HIGHER than the mass of our sun. So we do NOT have neutron star within our sun.
Now the question is what happens to a neutron star?
For one thing it is more massive than Sol or it must be a white dwarf.
The surface neutrons should slowly decay into hydrogen atoms.
No surface neutrons. That would be degenerate matter. Mostly protons and alpha particles within a sea of electrons. This would be a fairly thin skin or it would fuse catastrophically.

More
Skeptic_Heretic
5 / 5 (5) Feb 10, 2011
neutron stars will accrete hydrogen over time. One of several things will happen during this process.

Since the gravitational energy of a neutron star is impossibly high (on the order of a million, million G at the surface) the hydrogen will start stellar fusion, however, the hydrogen will burn out so quickly that the only relevant aspect is the speed of accretion of hydrogen. If the hydrogen is quickly accreted it will ignite and burn through all available fuel very quickly, causing a burst of brightness that will taper off over a few months. This is a Nova. Then you can accrete at a rather moderate pace and result in cataclysmic eruptions of fusion which sputter out, called a cataclysmic variable. Then you can accrete incredibly slowly, which will maintain a continuous fusion reaction blasting portions of the Neutron star away or blasting the entire star apart at once in a Type I supernova.

So if you think this is wrong, provide your alternate explanation for this phenomina.
Ethelred
5 / 5 (9) Feb 10, 2011
After enough hydrogen gas collects
It goes boom just like it does on a white dwarf. Fusion begins catastrophically. We can see this in Type II supernova.

The whole concept simply defies actual physics. Its all spitwadding and hoping the teacher doesn't notice the math is nonexistent. Oliver has NEVER run the numbers and simply holds his breath till his face turns blue when people mention the real numbers.

You want a neutron star within the Sun?

You need to prove that the minimum mass of a neutron star is LOWER than the mass of the Sun.

You meed to prove that hydrogen on the surface of the neutron star would NOT fuse catastrophically.

You need to show that the metals formed by the initial supernova would be captured by the neutron star despite the know high velocity of the ejecta.

You need to show that bound neutrons undergo beta decay and it has never been observed.

Please note that these things presently appear to be contrary to real physics.

Ethelred
Question
1 / 5 (8) Feb 10, 2011
SH and Ethlred: neither one of you offered and explanation for the heavy metals orbiting our sun.
During the sun's convalescing phase all the heavy metals would have ended up in the center of the sun.
Where are your answers??
As for all the question you have asked me, try answering them yourself, you cannot with any more certainty than I can.
I will answer this one though with a question, why wouldn't neutrons decay on the surface of a neutron star? As far as I know gravity has no effect on decay rates.
And this one with a question also, does hydrogen fuse catastrophically in the sun? No, so why should that always be the case on the surface of a neutron star?
Skeptic_Heretic
5 / 5 (3) Feb 10, 2011
neither one of you offered and explanation for the heavy metals orbiting our sun.
We both offered the same one, and you aren't paying attention.
During the sun's convalescing phase all the heavy metals would have ended up in the center of the sun.
According to what?
As for all the question you have asked me, try answering them yourself, you cannot with any more certainty than I can.
Incorrect, and not only can we answer those questions, but we can produce observational evidence for our answers, which you cannot.
I will answer this one though with a question, why wouldn't neutrons decay on the surface of a neutron star?
Because they are bound.
And this one with a question also, does hydrogen fuse catastrophically in the sun?
No.
No, so why should that always be the case on the surface of a neutron star?
Because a neutron star is not a sun-like star. They're not made of the same materials.

Do you think that Iron and Aluminium are the same too?
Question
1 / 5 (8) Feb 10, 2011
Ethelred:
Fits the present day size of the sun nicely, after all neutrons lose mass when they decay.

Quote NASA: "A neutron star is about 20 km in diameter and has the mass of about 1.4 times that of our Sun. This means that a neutron star is so dense that on Earth, one teaspoonful would ..."

imagine.gsfc.nasa.gov/docs/science/know_l1/pulsars.html
Question
1 / 5 (8) Feb 10, 2011
Quote
"Orbiting particles are not separated by mass because the velocity of the orbits is dependent on distance and independent of mass."

This is true but not during the convalescing stage, during that phase they are separated by "weight".

And SH your answer proves my point.
Gawad
5 / 5 (7) Feb 10, 2011
SH and Ethlred: neither one of you offered and explanation for the heavy metals orbiting our sun.
What...are you talking about???
Gawad
5 / 5 (7) Feb 10, 2011
During the sun's convalescing phase all the heavy metals would have ended up in the center of the sun.
Where are your answers??
Convalescing??? Was the Sun sick? Anyway, there's a huge amount of convection happening in the Sun, just as there is convection on Earth, only much much more so. Why do you think there is uranium in Earth's crust, for example?
Question
1 / 5 (6) Feb 10, 2011
Gawad: Perhaps there is a better word than "convalescing" but I cannot think of one. But one of the meanings of convalescing it to grow stronger and that does describe the formation of a star.
You also do have a point about convection playing a part in mixing. But don't forget when the sun was condensing (is that better?) it was not the churning nuclear furnace of today.
Skeptic_Heretic
5 / 5 (4) Feb 10, 2011
Question, do you think that Fusion takes place on the surface of main sequence stars? Your answer will explain why your perception is so skewed if my guess is correct.
Question
2.3 / 5 (3) Feb 10, 2011
Question, do you think that Fusion takes place on the surface of main sequence stars? Your answer will explain why your perception is so skewed if my guess is correct.

No.
Gawad
5 / 5 (6) Feb 10, 2011
why wouldn't neutrons decay on the surface of a neutron star? As far as I know gravity has no effect on decay rates.
It's not about decay rates, it's because bound neutrons can't decay, except in unstable nuclei. Now, a neutron star is essentially a gigantic nuclei bound by gravity rather than the strong force. How stable or unstable is it? I don't know. But afaik QM dictates that beta decay will be prevented in the same way regardless of which source (gravity or the strong force) provides the binding energy. This is because in either case the issues of nuclear stability vs instability (decay) are the same...well of course apart from the fact that the neutron star is a macroscopic nuclei. In simpler terms, the proton that would result has to go somewhere because of its excess energy, but it typically has nowhere to go when the originating neutron is in a bound state. Oh, that and the electrons released in beta decay are normally free, so no hydrogen is directly formed.
Gawad
5 / 5 (7) Feb 10, 2011
Ethelred:
Fits the present day size of the sun nicely, after all neutrons lose mass when they decay.

Quote NASA: "A neutron star is about 20 km in diameter and has the mass of about 1.4 times that of our Sun. This means that a neutron star is so dense that on Earth, one teaspoonful would ..."

imagine.gsfc.nasa.gov/docs/science/know_l1/pulsars.html
Question, a neutron star is bound by gravity. Gravity that is almost unimaginably strong. If you were somehow teleported to one's surface you would be liquefied into a slick less than one micron thick within a millisecond. Without the neutron star's own mass to provide that gravity, wich stabilizes the neutronium that makes up the neutron star, the NS will blow itself apart. And the minimal amount of mass needed to generate the gravity needed to form stable neutronium is roughly 1.5 solar masses. So how can the Sun have a NS inside it?
Question
1 / 5 (6) Feb 10, 2011
Gawad: Whether our sun still has a remnant of a neutron star in its center, I cannot even offer a guess.
As for gravity having an affect on neutron decay decay rates, I would like to see your source for that information.
That would also contradict what Ethelred stated earlier about neutron stars have catastrophic nuclear flares from time to time.
Gawad
5 / 5 (5) Feb 10, 2011
Gawad: ...As for gravity having an affect on neutron decay decay rates, I would like to see your source for that information.
I explicitly wrote it wasn't about decay rates so I don't know where you're getting that other than you've decided to troll, can't read or can't be bothered to. Given that there are scores of reliable internet sources you could consult to learn something about neutron stars, supernovas and stellar evolution, instead of relying on Physorg's living, breathing Shakespearean tragedy, Oliver K. Manuel, I tend to think the latter. Either way, not cool. That would also contradict what Ethelred stated earlier about neutron stars have catastrophic nuclear flares from time to time. No, because the mechanism Eth refers to involves the accretion of hydrogen from companion stars, not the spontaneous formation of hydrogen from beta decay on a NS's surface. And you would know that if you bothered to read just the BASICS. Never mind getting into degenerate matter.
Gawad
5 / 5 (6) Feb 10, 2011
Correction...
That would also contradict what Ethelred stated earlier about neutron stars have catastrophic nuclear flares from time to time.
No, because the mechanism Eth refers to involves the accretion of hydrogen from companion stars, not the spontaneous formation of hydrogen from beta decay on a NS's surface. And you would know that if you bothered to read just the BASICS. Never mind getting into degenerate matter.
Question
1 / 5 (9) Feb 10, 2011
Gawad: I accept that a companion star can be the source of hydrogen that explodes on the surface of a neutron star. That is not to say I accept it as the only source, I don't.
But I am sorry to read that you do not have time to look up a source to back up your claim that gravity has an effect on the decay rates of neutrons. So I will disregard that until I find out otherwise. I do not accept hearsay as facts.


Gawad
5 / 5 (3) Feb 10, 2011
Gawad: ...But I am sorry to read that you do not have time to look up a source to back up your claim that gravity has an effect on the decay rates of neutrons.
For the second time: I made no mention of "gravity [having] an effect on the decay rates of neutrons". That was YOU. Seriously, get some remedial reading help; it'll go a long way to helping you sort out what ideas are associated together as well as which are not, and help you practice which ideas are to be attributed to whom. Among other problems.
Question
1 / 5 (3) Feb 10, 2011
Quote Gawad:
Question, a neutron star is bound by gravity. Gravity that is almost unimaginably strong. If you were somehow teleported to one's surface you would be liquefied into a slick less than one micron thick within a millisecond. Without the neutron star's own mass to provide that gravity, wich stabilizes the neutronium that makes up the neutron star, the NS will blow itself apart. And the minimal amount of mass needed to generate the gravity needed to form stable neutronium is roughly 1.5 solar masses. So how can the Sun have a NS inside it?

If you are not claiming that gravity is what is keeping the neutronium (neutrons stablized) bound what are you claiming??
Gawad
5 / 5 (4) Feb 10, 2011
Oh wait a minute. You mean for my claim that neutrons within neutron stars won't undergo beta decay? (That's NOT the same thing as saying "gravity affects decay rates", by the way!) No, I don't have a direct source that deals with beta decay in neutron stars and frankly I would be surprised one exists.

My claim is based on the fact that QM & symmetry principals (energy conservation) prevents beta decay in stable nuclei. A neutron star is a gigantic gravitationally bound and stabilized nuclei that has already undergone MASSIVE inverse beta decay. The latter is just a fact, plain and simple. Now what I'm saying is that BOUND is BOUND. Just because it's as a result of gravity overwhelming the electromagnetic force rather than bound as a result of strong force interactions DOESN'T SUSPEND QM restrictions on beta decay.

Sheesh guy! You're the one making outrageous claims about some kind of neutron star origin for the Sun, and in spite of the fact that YOUR claims violate known physics.
Gawad
5 / 5 (4) Feb 10, 2011
If you are not claiming that gravity is what is keeping the neutronium (neutrons stablized) bound what are you claiming??
*SIGH*

O.k. Let's make sure we're gettign this stright. Gravity IS what binds and stabilizes NEUTRONIUM. Gravity does NOT bind and stabilize individual neutrons or normal, elemental nucleons.

Now, when did I write that this had anything to do with *decay rates*? I don't give a flying fig about rates, clocks and tic tocs. If you want to get into how GR impacts decay rate in different reference frames that whole other kettle of fish.

What I'm saying is BOUND is BOUND. Doesn't matter if it's as a result of gavity (in the case of neutron stars) or the strong force (in the case of normal nuclear matter): you'll have the same QM (pauli exclusion principle) and symmetry principle (conservation of energy) restrictions on beta decay.

And if that's not good enough for you, that's fine. I'm sure Oliver would love to have you as his protege.
Question
1 / 5 (8) Feb 10, 2011
Gawad:
You need to go back and reread what I said, I have no idea as to whether there is a remnant of a neutron star in the center of our sun. My only claim is that our sun most likely originated from a supernova and therefore neutron star.
And secondly, show me one thing I claimed that violates know physics.
Now it appears you did make a claim that violates physics by your use of the word neutronium.
One thing you cannot seem to understand is that the neutrons on the surface of a neutron star are not bound by anything other than gravity.
And you cannot show me any proof that gravity prevents neutrons from decaying!

Question
1 / 5 (8) Feb 10, 2011
Neutronium is alchemistry, not even close to having been proven to exist.
Gawad
5 / 5 (5) Feb 10, 2011
Gawad: You need to go back and reread what I said, I have no idea as to whether there is a remnant of a neutron star in the center of our sun. My only claim is that our sun most likely originated from a supernova and therefore neutron star.
I did reread it. That's why I said you claimed an outrageous neutron star ORIGIN for the Sun...Sun...Sun. And here, you do it again
show me one thing I claimed that violates know physics.
Bound neutrons undergoing beta decay
Now it appears you did make a claim that violates physics by your use of the word neutronium.
Really??? Well watch THIS:

NEUTRONIUM!

NEUTRONIUM!

NEUTRONIUM!

Wow, that's 3 more times I must have violated physics. Neat eh?
One thing you cannot seem to understand is neutrons on the surface of a neutron star are not bound by anything other than gravity.
To each other, YES. Is there an echo in here?
And you cannot show me any proof that gravity prevents neutrons from decaying!
Wow, feel any better?
Gawad
5 / 5 (5) Feb 10, 2011
Neutronium is alchemistry, not even close to having been proven to exist.
Stop trolling, Q. You're making yourself not even worthy of answering. Do some reading on neutronium and how the word is used in scientific circles. (Not pseudo-scientific pentagrams.)

You're the one who started prattling about neutron stars. What do you think they are made from? Balsa wood?

Face.

Palm.
Question
1 / 5 (6) Feb 10, 2011
You have got me chuckling now, thanks for making my day.

Now let me answer the one point you claim I am violating the laws of physics on. I am not the one claiming bound neutrons cannot decay, and yes even by beta decay. It happens all the time in radioactive isotopes.
Again, neutrons on the surface of a neutron star are not bound by anything other than gravity and they most certainly can decay.
Show me otherwise!!
Skeptic_Heretic
5 / 5 (3) Feb 10, 2011
Question, do you think that Fusion takes place on the surface of main sequence stars? Your answer will explain why your perception is so skewed if my guess is correct.

No.
Then why are you acting as though it does?
Again, neutrons on the surface of a neutron star are not bound by anything other than gravity and they most certainly can decay.
Show me otherwise!!
You do realize that gravity is not the only force involved, right?>
Question
1 / 5 (6) Feb 10, 2011
SH: I do not think fusion takes place on the surface of main sequence stars but that does not mean it could not take place on or very near the surface of a neutron star. Gravity would be crushing there.

I know forces other than gravity are on the surface of a neutron star, like temperature increases from absorbed EMR and neutrinos from the outside. Now if you are implying that the strong nuclear force is involved, it isn't. Have scientist ever created a ball of just neutrons here on earth?
Skeptic_Heretic
5 / 5 (5) Feb 11, 2011
SH: I do not think fusion takes place on the surface of main sequence stars but that does not mean it could not take place on or very near the surface of a neutron star. Gravity would be crushing there.
And that is why the fusion is catastrophic. The gravity is so intense that fusion of atoms on the surface is far more rapid than it is even in the core of a main sequence star.
Now if you are implying that the strong nuclear force is involved, it isn't.
Actually, you'd be the one insisting that the strong nuclear force is involved, otherwise how would your Neutron star be able to prevent sinking the neutrons freed from fusion events?

That's the problem here, you mount a self defeating argument because you're ignorant of the theories that explain these phenomina.
Gawad
5 / 5 (5) Feb 11, 2011
You have got me chuckling now
I try not to take stuff like this too seriously. After all, we're just playing for protons. Er, peanuts.
I am not the one claiming bound neutrons cannot decay, and yes even by beta decay. It happens all the time in radioactive isotopes.
In unstable nuclei, that's right. As I said in one of my first posts above, I wouldn't really know how to measure NS nuclear stability, so I grant that some beta decay might occur. But bare in mind this would only be on the very surface, and in an environment where conditions hugely favour inverse beta decay. There's no way you can build a normal star back up from this process.
neutrons on the surface of a neutron star are not bound by anything other than gravity
So? Gravity not good enough for *neutronium* for you? In that environment it's stronger than the residual strong force that binds nucleons
and they most certainly can decay.
So YOU say
Show me otherwise!!
Nope, you pony up if you have it.
stealthc
5 / 5 (1) Feb 12, 2011
yay it's make belief astro-physics day on physorg. LOL.
MorituriMax
5 / 5 (4) Feb 13, 2011
One theory is that our sun was once a supernova.
No, that's a shitty hypothesis (from a fellow physorg poster) that has been disproved by just about every observation of stellar evolution known.

Stop throwing the word theory around if you don't know what it means within the realm of science.

And what is the present theory, all the heavy metals "just happened to be in the neighborhood when the sun formed?" Now that is dreaming.


Dude, just let it go. Stop making yourself look more and more like a bigger jackass. You were wrong. Move on.
MorituriMax
not rated yet Feb 13, 2011
There is still not a good explanation as to how so much heavy metal escaped from the center of the sun during its convalescing stage.
If the sun started out as giant star that exploded into a supernova it can be explained quite well, including the angular momentum in the heavy metals needed to orbit the remaining neutron star. It also explains the layers of heavy to lighter elements the further one goes from the center of the explosion.
As for Oliver's explanation of the origin of the sun's energy, I do not accept that either, but the source of that energy can be explained.
After the supernova a neutron star would be remaining. Now the question is what happens to a neutron star? The surface neutrons should slowly decay into hydrogen atoms. After enough hydrogen gas collects on the surface of a neutron star, it should start fusing again warming the convalescing planets.

You aren't by any chance the "scientist" that does a lot of work for neal adams, are you?
antialias
not rated yet Feb 14, 2011
Heck, stellar fusion will only get you as far as iron on the periodic table, so anything heavier than that can *only* be created in a supernova explosion afaik.


While it is true that any fusion that goes beyond hydrogen consumes more energy than it creates this does NOT mean that heavy metals aren't created during the normal operations of a sun (even before any supernova event).

It's just a probabilistic distribution: Not all nucleons in the sun have the same (the average) energy at all times. There are rather large fluctuations. So you do get all kinds of fusion products even during the early stages (only with sharply diminishing probabilities) not only H to He, etc. This includes 'freak' fusion products that are heavier than iron.
antialias
5 / 5 (1) Feb 14, 2011
..erm...that should be "any fusion that goes beyond iron"...sorry.