Neutron stars Definition and 109 Threads

Dear all, I'm starting to study neutron star accretion and a lot of physical phoenomena coming from different scales come along and a consistent picture is frankly hard to grasp. But for now, a real mind boggling question can't exit my mind. Are Neutron stars, as a whole Quantum, or...

Homework Statement About neutron stars we can say that: a) They are newborn stars b) They are generated when a Solar-type star dies c) They are generated when a very massive star dies d) They are in the main sequence Homework Equations None. The Attempt at a Solution I'm...

in general how to calculate binding energy of neutron star? in simple details, what tricks may be included in such a problem..

Does the strong force have any major role in neutrons stars other than obviously holding individual nuclei together? Would low energy neutrons tend to "clump" together in the core?

If Neutron stars are what they are... I mean made of literally only neutrons ...how do they generate such immense magnetic field (of the order 10^8 or something) .. I think the name is somewhat misleading and it ought to have a near half ratio of protons ...But still being so compact how...

2 closely orbiting massive objects are predicted to deserve the fabric of spacetime so much that they will release a ripple of gravitational waves. When geavitational waves are released, they slowly loose velocity energy and spiral into one another. 2 pulsars were discovered orbiting each other...

The situation is this: In a neutron star the Coriolis force induces Rossby waves, just like on Earth. These are waves with very long wavelength -- like halfway around the Earth -- and very large volume but very little amplitude, like fifty meters. On Earth they have a big effect on climate...

what if...Neutron stars I know likely its been answered but if two neutron stars collid, it wouldn't seem that there combined massess would forum a black hole...if I recall that any matter striking the surface of a neutron star impacts with such violence that there is a massive explosion. So I...

If proton decay does not occur, will neutron stars just last for eternity unless something collides with them?

After reading "The Five Ages of the Universe" by Greg Laughlin and Fred Adams, I wondered, if all matter composed of ordinary atoms (protons decay) decay, and black holes decay due to Hawking Radiation, do neutron stars decay in any way? They are composed entirely of neutrons that are kept...

I need so advise on SPH open source code to use to look at mergers and rotating objects... if anyone has some links or tutorials? Thank you!

Homework Statement An open cluster is observed to contain 1000 stars. Clusters contain many more low mass stars compared to high mass stars, reflecting the star formation process. This depen- dence of the number of stars formed in a given mass range is expressed in the so-called initial mass...

I have just attended a talk, where the speaker (a professor in Hong Kong University) claims that neutron stars don't collapse due to "nuclear forces". He further explains that those nuclear forces are residual strong forces (i.e. exchange of pions). However, the mainstream saying (according to...

I have a scientific background in materials science. However this is one type of material that we don't exactly learn about! Let's say you have a neutron star approaching a comparable mass black hole. As the neutron star approaches the event horizon for such a comparable black hole, tidal...

what is the difference between a neutron star and a black hole?

It is my understanding that when an electron drops to a lower orbital that 2 photons of light are produced. The moving electric charge produces EM radiation just like moving charges in a radio transmitters antenna produce EM radiation. Energy in the form of radiation, heat, or whatever else, can...

I was wondering, does anyone know of a lower limit on the mass of a neutron star from fundamental physics? That is, the smallest it could be before its pressure would make it explode. I don't mean the Chandrasekhar limit, as that's the upper limit for a white dwarf. Neutron stars occurring...

Homework Statement Deep in space, two neutron stars are separated (center-to-center) by a distance of 18 X 106 km apart. Neutron star A has a mass of 153 X 1028 kg and radius 52000 m while the neutron star B has a mass of 159 X 1028 kg and radius 72000 m. They are initially at rest with...

Will black dwarfs eventually quantum tunnel into neutron stars if proton decay doesn't occur?

I'm wondering about the visual appearance of neutron stars up close. Do they continue to emit light like a white dwarf? Can cooled ones be gray or black? The xray emissions from pulsars will not be visible to us. Due to their high mass, they will bend light in a similar manner to a black hole...

I thought others might be interested in this: http://arxiv.org/abs/1011.6142 As a nuclear physicist, I don't find it surprising to hear that neutron stars are superfluid. Nuclei are superfluid. I'm not clear on the relationship between superfluidity and cooling. Can anyone explain this using...

First of all, I know that that very large stars tend to form black holes, and smaller stars, but still massive in comparison to our sun, tend to form neutron stars. My question is, if matter is lost when a star collapses into a black hole, but can still form one, why is it that it is a star...

If proton decay does not occur, are neutron stars immortal? I was hearing that that was the case.

If black holes are not real, just wondering? By the way they may or may not exist. But since some people don't believe they exist and some do, then if you DO NOT , how do you explain what happens to neutron stars that are 20 -25 the size of the sun? typo in the title, it should read: " what...

I always here about neutron stars and black holes sucking the gs from their companions. However, a star loses mass before it becomes a neutron star so I don't understand why it afects its neighbor more when it is a neutron star than when it was a regular star.

Neutrinos can pass through solid objects like the Earth easily, and a light-year of lead would only stop half of them from passing through. What about something very dense like a white drawf or neutron star? How readily can neutrinos penetrate that? What % flux reduction would be achievable...

Homework Statement The Gravitational binding energy of an object consisting of loose material, held together by gravity alone, is the amount of energy required to pull all of the material apart, to infinity. the gravitational binding energy Ug is roughly given by GM^2/R. how fast do you have...

Homework Statement Certain neutron stars (extremely dense stars) are believed to be rotating at about 6 rev/s. If such a star has a radius of 15 km, what must be its minimum mass so that material on its surface remains in place during the rapid rotation? G=6.67*10-11m3 kg-1 s-2 Homework...

Gravity acceleration value depend on planet and stars mass. On the earth, the well known average value is 9.81 ms-2. On the sun, I read 1200 ms-2; is it true ? does exist a curve giving values depending on mass ?

Hi, in a lecture I was told that the cooling of neutron stars cannot happen via the 'direct' Urca process (beta decay and inverse beta decay), because the created particles cannot go into occupied states (Pauli exclusion). The 'modified' Urca process was introduced, with an additional neutron...

I was wondering about the light emitted by one of these neutron stars. To my limited knowledge, neutron stars are among the discrete objects in the observable universe with the strongest gravitational and EM fields [black holes beat the living crap out of neutron stars, but that's besides the...

Neutron Stars and Special Relativity and General Relativity Here is a question which I can't quite wrap my head around: Suppose we have a Neutron Star that is borderline on the Chandrasekhar limit in its rest frame. In another frame, the Neutron star is moving. As a result, its density...

Since neutrons have no electric charge, how is it that a neutron star is able to produce a magnetic field? :confused:

can someone Explain the NS-NS or NS-BH or BH-BH mergers proposed to explain short GRB’s. Thanks

Not sure where to put this post, care more about what's happening on atomic scaI le so i put it here. I am currently taking Heat transfer for engineers and we were discussing the mechanicals for heat transfer, conduction, convection, raditation. In class my professor said that conduction is...

Homework Statement "During most of its lifetime, a star maintains an equilibrium size in which the inward force of gravity on each atom is balanced by an outward pressure force due to the heat of the nuclear reactions in the core. But after all the hydrogen "fuel" is consumed by nuclear...

Hey! I have a question, whose answer I was unable to get after reading some articles regarding neutron start. I've understood that neutron stars lose their rotational energy and emit fragments of it to earth, thus slowing down through the years. I know that this process takes billions of...

Hi guys, I'm not to great at physics and all but I want to learn more. I hope you guys can help me in that aspect.First of all, how do neutron stars form? I was told their electrons shrink into their nucleuses and therefore the whole star shrinks, but what causes the atoms to behave like that?

Neutron stars represent the final stage of life for some massive stars. Typically, they have radii of 10 km. Determine the magnitude of the centripetal acceleration for a piece of neutron star matter on the star surface at the equator (so the matter moves in a circle of radius 10km). Assume...

I was intrigued by this paper, and apparent implications for Smolin's cosmic natural selection [CNS] conjecture. http://arxiv.org/abs/astro-ph/0609644 Observational constraints on quarks in neutron stars Authors: Pan Nana, Zheng Xiaoping Comments: 16 pages,6 figures We estimate the...

We were having a little chat in my physics lesson about neutron stars for our A level course, and nobody really understood why neutron stars have a magnetic field if they are consist of neutrons, which are obviously neutral charge. We thought that you needed charged particles to create a...

I was reading about neutron stars and wonder if anyone can help me with something that puzzled me , namely what happens to the electrons in such a mass of atomic neuclii? I can only see there might be 2 possibilities .Either 1) that the electrons are expelled from the atoms during the collapse...

Is a neutron star held together mainly by the strong force? Are they dense enough so that this is the case, or is gravity the only thing to consider? What about black holes?

What are they? :confused:

I have a question about the time scale for a certain type occurance causing a neturon star to explode, and a related question about the conditions of this occurrance. If you have a binary star system with one of the stars being a neutron star, I read that if the other star sucks off enough...

quasars are highly active but extremely distant galaxies, right?what kind of galaxies are they and do they represent an earlier stage of the lives of the conventional galaxies?i've a vague idea that quasars a galaxies in which the supermassive black holes at the centres are actively gobbling up...

Are Neutron Stars the major factors of Proton Stars? :http://arxiv.org/abs/astro-ph/0506092 Why do Neutron Stars evolve from Proton Star collapse, and what is the next evolving stage?..if any? :http://arxiv.org/abs/astro-ph/0506100 Can a further collapse occur that does 'not' produce...

http://www.physics.ubc.ca/~heyl/ns2005/prospectus.html Neutron Stars at the Crossroads of Fundamental Physics I. Organizers Jeremy Heyl – University of British Columbia Vicky Kaspi – McGill University Feryal Özel – University of Arizona Krishna Rajagopal – Massachusetts Institute...

Where can I find PDF "Black holes White Dwars and Neutron Stars" Gents, Could u pls advise me if you know where can i find book "Black holes White Dwars and Neutron Stars" Authors Shapiro, Tuekolsky (free PDF or DJVu or other format) Thks

What are the forces that give asteroids their shapes? And what shape do neutron stars that do not rotate around its axis have?