Why do both poles of a radio pulsar emit radio waves?

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Discussion Overview

The discussion revolves around the emission of radio waves from both poles of a neutron star, specifically addressing the mechanisms behind this phenomenon and the implications of magnetic field interactions. Participants explore theoretical aspects, including synchrotron radiation and the behavior of particles in magnetic fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that both magnetic poles of a neutron star emit radio waves with similar characteristics, suggesting a synchrotron nature of the radiation.
  • Others question the mechanics of particle emission at the poles, arguing that particles at one pole are pushed upward while at the other they are pressed against the star, potentially affecting emission.
  • There is a discussion about the Lorentz force and how it influences particle movement in magnetic fields, with some participants emphasizing that magnetic fields do not push particles like electric fields do.
  • One participant notes that for emission to occur, particles must move, and questions the conditions under which pulsars emit radiation, suggesting that if particles move along field lines, the emission would be continuous rather than pulsating.
  • Another participant explains that pulsars pulse due to the misalignment of their magnetic poles and rotational axis, leading to periodic emissions as the beam sweeps past observers.
  • There is a suggestion that radiation may not be limited to the poles but could involve the entire surface of the star, raising questions about the nature of synchrotron radiation in this context.
  • A participant calls for peer-reviewed sources to support claims made in the discussion, indicating a need for more rigorous evidence in the arguments presented.

Areas of Agreement / Disagreement

Participants express differing views on the mechanisms of radio wave emission from neutron stars, with no consensus reached on the specifics of particle behavior and emission processes.

Contextual Notes

Some claims rely on assumptions about the behavior of particles in magnetic fields, and there are unresolved questions regarding the conditions under which pulsars emit radiation and the implications of synchrotron radiation theory.

Line_112
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TL;DR
According to generally accepted ideas, both magnetic poles of a neutron star emit radio waves. But the poles of a magnet are opposites in their properties.
According to generally accepted ideas, both magnetic poles of a neutron star emit radio waves. Moreover, they have the same radiation spectrum, average pulse amplitude, and pulse microstructure. The radiation is supposed to be of a synchrotron nature. But the poles of a magnet are opposites in their properties. If particles are pushed upward at one pole and begin to emit during acceleration, then at the other pole they will be pressed even more strongly against the star and a similar effect will not occur there.
 
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Line_112 said:
If particles are pushed upward at one pole and begin to emit during acceleration, then at the other pole they will be pressed even more strongly against the star and a similar effect will not occur there.

Why exactly? Do you know how Lorentz force works? What does changing the sign of ##\vec{B}## do to particles movement? Hint: magnetic fields don't push particles the way electric fields do.

Btw, this is high school level physics.
 
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weirdoguy said:
Hint: magnetic fields don't push particles the way electric fields do.
In any case, in order to emit, the particles must move, but where? If along the field lines, the star will glow constantly, and not pulsate. And if not, then its entire surface will glow, that is, again, continuously.
 
You did not check how Lorentz force works, did you? It's a high school topic, so there are plenty of materials. Particles move on a helix on both poles. The difference between poles is the chirality of helix.

EDIT: although I think that particles moving away from the star, move on helixes with the same chiriality. Anyways, that's not that important for OP question.
 
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Line_112 said:
In any case, in order to emit, the particles must move, but where? If along the field lines, the star will glow constantly, and not pulsate. And if not, then its entire surface will glow, that is, again, continuously.
Pulsars "pulse" because their magnetic poles and rotational axis don't align. The radiation emitted from the magnetic poles is constant. We only receive it when if the rotation of the pulsar causes the beam to periodically sweep past us. It's like seeing a lighthouse produce flashes even though its rotating light is always on.
 
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Janus said:
Pulsars "pulse" because their magnetic poles and rotational axis don't align. The radiation emitted from the magnetic poles is constant. We only receive it when if the rotation of the pulsar causes the beam to periodically sweep past us. It's like seeing a lighthouse produce flashes even though its rotating light is always on.
I know that, but the interesting thing is that the radiation will not be emitted only by the poles, but by the entire surface of the star. But even if only by the poles, the particles will move along curved lines of force, as indicated for synchrotron radiation in Wikipedia, and this is what is suspected of pulsars:
https://ru.wikipedia.org/wiki/Синхротронное_излучение
As a result, we should record it not only when the magnetic pole is facing us, but also in all other positions, since there will always be particles that will be facing us at that moment. During accretion, particles descend along the lines of force to the magnetic poles and radiate from there, so in these cases there really can be a cone. However, radio pulsars, as it is written, do not have accretion.
 
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Line_112 said:
According to generally accepted ideas, both magnetic poles of a neutron star emit radio waves. Moreover, they have the same radiation spectrum, average pulse amplitude, and pulse microstructure. The radiation is supposed to be of a synchrotron nature.
@Line_112 -- You need to post links to the peer-reviewed journal articles that support what you are saying. Wikipedia's synchrotron article is not sufficient for this purpose. Please post those links and point out where in the articles they are saying what you are claiming. Thank you.
 
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