Questions tagged [neutron-star]
Questions regarding a degenerate star that is mainly composed of neutrons.
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What would happen on earth if there was a surge in gravitational waves [duplicate]
There are claims that when massive objects merge some of their mass is converted to gravitational energy. Such as the following links:
https://astronomy.stackexchange.com/a/38727/2305
https://youtu.be/...
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Fraction of initial mass lost (radiated) by neutron star mergers compared to black hole mergers?
GW190521 black hole merger total mass calculation and missing mass, how does this happen? notes that there are about 9 solar masses missing from the final black hole.
GW170817 is the first observed ...
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If a pulsar's rotational and magnetic axes were aligned and both aimed at us, would we see a steady radio source?
In other words, a non-pulsing pulsar?
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Do the neutrons in neutron stars emit the radio waves?
Neutrons can, especially in extreme circumstances (and large concentrations) emit electromagnetic radiation. I specifically asked about this in Physics S.E. Has a free neutron ever been shown to ...
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How is angular momentum transferred between a neutron star and its accretion disk?
Accreting neutron stars can either gain or loose angular momentum via interaction with their accretion disks. This leads to either spin-up or spin-down. Which of the two is the case, depends on the ...
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If the sun is a second or third generation star, where is the neutron star? [duplicate]
It is widely believed that before the Sun was another star, more pristine in its composition (mostly Hydrogen and perhaps some Helium). And maybe before it was yet another. This blog explains this via ...
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Is there any synthetic spectrum software for neutron star?
Is there any software that can calculate the emergent spectrum of a neutron star photosphere, for Teff is about 1e7K, density is above 1e21-1e22 cm^-3 ? Output line wavelength is about 0-100A is ...
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Why can there be several seconds of lag between a binary neutron star merger and the emission of gamma rays from the same area?
Answers to: Gravitational waves and gamma ray burst: how were the error bars determined for this speed of gravity calculation? Was $H_0$ used? go into substantial detail explaining this determination. ...
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What is the “hypothesized lower mass gap” between 2.5 and 5 solar masses?
Searching here for "mass gap" yields nothing yet. Penn State's Black hole or neutron star? LIGO-Virgo scientists find mystery object in 'mass gap' begins:
When the most massive stars die, ...
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Can the Sun contain degenerate matter?
Degenerate matter (neutronium) is hypothesized to be very dense and, at a certain amount, unstable - in the sense of collapsing on itself and causing fusion. The result would be a massive fusion ...
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Are there neutron stars whose magnetic axis and rotating axis are the same, and if so what will happen?
I know that there's probably a higher chance of having a neutron star that has its magnetic axis inclined to the rotational axis rather than having it perfectly aligned.
If they are not aligned, the ...
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Is the object a pulsar
We have a star having 1.8 solar mass. Justify any four means (measurable/ observed properties) by which you can identify that the object is a Pulsar and not a white dwarf or a Black Hole.
So one ...
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In practice, can very high magnetic fields significantly alter the dynamics of an astronomical-scale bodies?
The direct effect of magnetic fields on the dynamics (as in the movements, trajectories etc of the bodies themselves, rather than lower-level phenomena like stellar winds and atmospheric degradation) ...
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How far away are the events that caused the gravitational waves that have been detected?
A certain number of gravitational wave events have been detected. Is it possible to know how far away the mergers that caused those gravitational wave events are?
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Is the atmosphere of neutron star solid, liquid or gaseous state? [duplicate]
Neutron star has a thin layer of atmosphere consist mostly of hydrogen and helium and is about less than a metre thick on average, but what wasn't stated in many articles I read is the state of matter ...
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How does the field decay of a magnetar power the emission of high-energy electromagnetic radiation?
In Space.com's Dr. Pulsar and Mr. Magnetar? 2 Star Types May Turn into Each Other (and in the linked video) "Tom Prince, a physics professor at the California Institute of Technology and a senior ...
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Can we detect pulsars that aren't “pointed” towards us?
A pulsar is a highly magnetized rotating neutron star that emits beams of radiation through its magnetic poles, in the direction of the Earth. This makes it seem to pulse, as seen from Earth. There ...
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How can I hear (or at least detect) a pulsar at home?
Scott Manley's video Using Relativistic Raytracing &X-Rays To See Detail on Surface Of Neutron Star talks about X-ray measurements using the NICER X-ray telescope attached to the International ...
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If we accelerate a neutron star to move at speeds comparable to light would it become a blackhole because of the added energy?
Could a neutron star turn into a blackhole if it is accelerated to near luminal velocities? And if it slows down after a while, does it become a neutron star again?
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What is the “radiation sound speed” inside an accretion column?
I was trying to read "A New Two-fluid Radiation-hydrodynamical Model for X-Ray Pulsar Accretion Columns" and its follow-up paper both by West et al. and came across a quantity called "radiation sound ...
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Neutron star size in different reference frames
What is the estimated size of neutron stars observed in their reference frame and in our reference frame?
That is, how bent is space-time around neutron stars?
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Could anything consume a small black hole?
Whenever I read about black holes, it is normally involving how they devour anything that comes too close... regardless of how big anything is.
But what if it were a really small black hole vs ...
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Neutron star r-process nucleosynthesis
The $r$-process in supernovae happens when a high flux of neutrons irradiates the heaviest abundant nuclei (in the region of iron), resulting in endothermic nuclear reactions.
To the extent that at ...
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Radiation from Neutron Star impact?
As I understand it, objects falling into an old/inactive/dead/non-pulsar neutron star would be ripped apart, form an accretion disc and eventually emit a burst of radiation as they fall onto the ...
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Is there evidence of super-heavy elements in the x-ray and gamma-ray spectrums of neutron stars?
It occurs to me, that between the surface and interior of neutron stars, gravitational pressure might produce super-heavy elements and that signatures of such elements might be detectable in the star'...
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A neutron star without a flat surface and an atmosphere?
In the Kurzgesagt video Atoms As Big As Mountains — Neutron Stars Explained they state that neutron stars have an atmosphere that reaches about 10 centimeters above the surface.
How is this possible?...
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Binary pairings that haven't been discovered yet?
Question: Are there any kinds of binary pairings that haven't been discovered yet? Any that are particularly significant, or that might shed some light on binary stellar evolution or theories of ...
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Roche Zone of a black hole vs Roche Zone of Neutron Star
Suppose a very unusually small back hole with the mass of about, lets say, 1.5 solar masses(hawking radiation should destroy a lot of mass let's assume). It thus would have a Roche limit smaller than ...
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What does “GPU-accelerated butterfly matched filtering over dense bank of time-symmetric chirp-like templates” mean? (GW170817)
A new analysis of gravitational wave (and other data) from GW170817 on 2017-Aug-17 has been published, strongly suggesting that the merger of two neutron stars resulted in a large, rapidly rotating ...
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A high-temperature isolated neutron star could be super-Eddington?
If the surface temperature of a young neutron star is hot enough, say, several KeV, its blackbody radiation could be super-Eddington?
Did any paper discuss this scenario before?
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Could an astronomical process create elements in the islands of stability?
I was reading about heavy elements recently, and I took note of the theorized islands of stability, and how some the elements involved are considerably heavier than anything we've been able to ...
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What is Propeller Effect exactly?
I find the original reference seems to be here. I still do not understand the mechanism. It is necessarily occur in neutron binaries? Anyone can introduce it in detail? This paper is old.
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How big should be a piece of neutron star to reach Earth's mass?
Imagine a neutron star could be broke into pieces.
How big would be the piece matching Earth's mass?
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Why aren't neutron stars full of dark matter?
Dark matter interacts with the gravitational force right? Well, unlike black holes, neutron stars are actually visible, and they're an enormous gravitational sink, so dark matter should collect to ...
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Why do neutron stars collide instead of just revolving around each other like planets revolve around the Sun?
We know about events like two neutron star colliding and resulting in a black hole, also collision of black holes, and collision of galaxies. But we never see a satellite such as a moon colliding with ...
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Is there a possibility that a white dwarf can turn into a neutron star or a black hole?
I know that a white dwarf is mainly balanced by electron degeneracy pressure and that if it gains more than 1.4 solar masses from any source (such as a companion star or a collision), it explodes as a ...
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Core collapse supernova vs Neutron Star
I am reading about massive stars and their final consequences. what I understood is massive stars after throwing out their outer envelop with masses > 1.4 solar Mass turn into neutron stars. But I ...
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What is the light that we see from a neutron star come from?
What hold the electrons in orbit? Is it gravity or the atomic attraction between the protons and neutrons?
I asked this question on Physics SE I hope I improved on the quality enough to do better ...
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Can we create neutron star by pressing earth? Or other objects?
Everywhere I can hear, that if we press anything to the right size, we create black hole.
Can we create neutron star by pressing, for example, our planet? And what if we press something bigger, like ...
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How do we know how fast the surface of a neutron star is rotating?
I understand that we can count pulses in time, but how do we know that the magnetosphere is rotating along with the surface of a neutron star?
Can we measure the rotation of a neutron star in any ...
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Could life survive on a planet orbiting a neutron star? [closed]
Suppose an Earth-like planet orbits a neutron star, though specifically not a pulsar. Is there any possible orbit, around any possible neutron star, in which the planet could support human life?
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Why is neutron star a star?
I am wondering since neutron star is smaller than the average main-sequence stars and it doesn't produce energy via fusion so why do we still call it a star?
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Did the scientists really observed gold and platinum being created from kilonova?
I read that after LIGO and Virgo interferometers detected gravitational waves signal from a kilonova, many ground based telescopes quickly turns their mirrors towards the spot and "sees" gold and ...
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Can a Neutron Star become charged?
If you keep adding electrons or protons to a Neutron star, what would happen? Are there decay processes that convert them to neutrons in the absence of the oppositely charged particle?
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“Who saw” the binary neutron star merger first? What was the sequence of events? (GRB/GW170817)
I'm trying to read Multi-messenger Observations of a Binary Neutron Star Merger the "cast of thousands" OPEN Access ApJ letter 848:L12 (59pp), 2017 October 20 https://doi.org/10.3847/2041-8213/aa91c9 ...
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Energy Source for Gamma Rays from Merging Neutron Stars
When the two neutron stars merged in the latest event, large amounts of gamma rays were emitted. Given that their deorbitting is a result of gravitational wave production, where does the energy for ...
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Which atom is a Neutron star made of?
I understood that everything was made of Atoms.
An atom is the smallest constituent unit of ordinary matter that has
the properties of a chemical element. Every solid, liquid, gas, and
plasma ...
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Are binary neutron star mergers needed to explain the abundance of gold?
The NPR News item Astronomers Strike Gravitational Gold In Colliding Neutron Stars mentions and quotes "Daniel Kasen, a theoretical astrophysicist at the University of California, Berkeley:"
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Why is the discovery of merging neutron stars important?
I'm fairly certain people here will have heard about it, already, but apparently, two supernova leftovers clashed some 130 million years ago and some billion billion kilometres away ...
What I haven'...
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Do neutron stars shine?
Ignore pulsars and the like, just a neutron star in empty space – does it emit light and neutrinos?
