Questions tagged [pulsar]
Questions regarding neutron stars which emit regular pulses of electromagnetic radiation.
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What causes a star to become a pulsar?
What processes does a star undergo to become a pulsar? Does it take a very specific star with a certain set of qualities such as "Just the right mass, diameter, and composition," or is it a freak ...
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How Would a Neutron Star Actually Appear?
Having seen many pictures produced by artists of neutron stars and planets that orbit some of them, I was wondering how a pulsar would appear to a human being, in visible light (assuming the intense ...
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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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What causes fast moving pulsars to move so fast?
This article investigates the traces left in the ISM by fast moving pulsars. Is there a mechanism specific to pulsars that causes them to move so fast, or are there just as many fast moving stars?
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Does the observed period of a pulsar change with the time of year?
Over in the Physics SE a question was posted asking about the difference in the time dilation of the Earth between perihelion and aphelion:
Does Earth experience any significant, measurable time ...
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What is the probability of seeing a neutron star as a pulsar?
Pulsars are neutron stars that emit a beam of electromagnetic radiation that is not aligned with its rotation axis. If the Earth passes through that beam of radiation, we see a pulsar. Pulsars are ...
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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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What causes a neutron star to become a pulsar?
Leading on from this pulsar question, what criteria/processes make neutron stars become pulsars, do all neutron stars become pulsars?
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Pulses from a pulsar
What is/was the motivation behind attributing the pulses received from a pulsar to the rotation of an object (neutron star) and emission from the magnetic poles (of the said neutron star), given that ...
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What is the significance of the discovery of a pulsar flipping between radio and x-ray emissions?
This morning on the radio I heard about the discovery of a pulsar that, due to its proximity to a companion star, was flipping between a state where it emitted radio waves and one where it emitted x-...
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Crab Nebula Time Period
I've learned that the time period for a rotating neutron star, i.e., a pulsar is very accurate and can be used as an interstellar clock. But according to Walter Lewin's 8.01 Lec 19 on classical ...
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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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Why are the magnetic poles of a pulsar so far off the rotational axis, yet stable?
My understanding is that a pulsar is a neutron star whose magnetic poles don't coincide with the rotational poles and whose magnetic poles sweep through Earth (allowing us to hear radio noise).
If we ...
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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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Rotation direction of Pulsars
Pulsars are rotating neutron stars observed to have pulses of radiation at very regular intervals that typically range from milliseconds to seconds. It has a very strong magnetic fields which funnel ...
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Is there any well-populated list or database of pulsar "glitches"?
Besides listing which pulsars have ever actually glitched, it would hopefully also include some historical data on their periods before and after they glitched.
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What is a typical polar angle of a pulsar beam?
I've found many articles on the geometry of pulsar beams, but I have not been able to find what would be a typical angle for the beam cone. Illustrations I've found seem to look like it might be 1 or ...
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What are realistic and unrealistic values for the high energy gamma ray spectral indices of pulsar wind nebulae?
This summer, I was working on a project fitting very high energy gamma ray spectra of the Crab Nebula, a pulsar wind nebula. At energies about $\sim$1 TeV, a simple power law suffices, i.e. $\phi(E)\...
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Why do pulsars turn "off" from rotation?
I was looking at the Pulsar wikipedia article
and I came across an interesting aspect that said pulsars turn off from rotation:
When a pulsar's spin period slows down sufficiently, the radio pulsar ...
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Can't pulsars and stars be used for gravitational wave measurement?
Suppose that we collected photons from a distant star, and they arrive regularly at 15 photons every microsecond onto a CCD, when a gravity wave bends space time, wouldn't the regular 15 photons graph ...
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Is "magnetars don't last long — just a year to a few years" really true? Is it a misquote or perhaps taken out of context?
NASA's Two Sides of the Same Star discusses the relationship between pulsars and magnetars and contains a video also linked below.
At 02:13 it quotes "Tom ...
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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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How did Jocelyn Bell Burnell discover the periodicity of CP 1919?
According to Wikipedia,
in 1967, a radio signal was detected using the Interplanetary Scintillation Array of the Mullard Radio Astronomy Observatory in Cambridge, UK, by Jocelyn Bell Burnell. The ...
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Do pulsar beams interact with the interstellar medium?
Pulsars are rotating objects that emit a beam in a direction that is not aligned with the axis of rotation. Because of this, we see them as a periodic pulse. If the beam isn't towards us, we don't see ...
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What are the main ways that pulsar "glitches" are noticed and documented? Do they have to be caught in the act of glitching to be catalogued?
This answer to Is there any well-populated list or database of pulsar "glitches"? mentions two large databases; (Jodrell Bank and ATNF's pulsar catalog) but neither question nor answer ...
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How to tell a pulsar is rotation-powered or accretion-powered?
We need to calculate P/Pdot?
A pulsar may switch between theses two states.
For a rotation powered pulsar, it can pulse and, the pulsed Lx can be much larger than the luminosity given by its ...
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How do we know pulsars have two beams?
Pulsars are neutron stars the emit a beam of electromagnetic radiation that is not aligned with their rotation axis. So we can only see a neutron star as a pulsar if the beam crosses Earth's path.
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Rule of Exception in All Nearest Objects
I once heard of a strange phenomenon, but now cannot find anything about it on the Internet. I might be looking for the wrong keywords or misremember some relevant aspect. So maybe someone here can ...
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Does Doppler shift affect apparent pulsar frequency?
We know that redshift and blueshift is the result of the frequency of light waves reflected or emitted by an object lengthening or shortening due to the relative velocity of the observer moving away ...
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Is the pulsar map on the Pioneer/Voyager probes only meaningful for earthlings?
The Pioneer probes brought plaques (and later the Voyagers two golden discs) with a "pulsar map" imprinted on them. The purpose of the map is to make the position of the Sun clear for an ...
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How bright is the Crab Pulsar's 30 Hz modulation in visible light? What color is it?
This answer to Has great eyesight been necessary for astronomers? mentions Astronomer Jocelyn Bell Burnell's recounting of a likely first visual observation of a pulsar. This can be found for example ...
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Can a pulsar hit us with both beams?
Can a pulsar have an axial tilt close enough to $90^\circ$ to hit us with both beams for two pulses per rotation?
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Is there a significant population of neutron stars outside the galactic plane?
Pulsar kicks originating from supernovae can impart neutron stars with speeds of 100-500 km/s, often at or close to the escape velocity of the Milky Way. Even if a pulsar fails to escape the galaxy, ...
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which pulsar has the longest spin period so far?
Vela X-1 has a 283s spin period, while this one may have a 2.7hr spin period.
However neither of them is included in ATNF catalog.
They are not included in $p-\dot{p}$ diagram either. The longest ...
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How did the Hulse-Taylor Pulsar Provide Confirming Evidence of General Relativity?
What measurements and observations of the Hulse-Taylor Pulsar agreed precisely with the predictions of general relativity, and how did these measurements support the theory?
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How to interpret illumination in "pulsar cannonball" image
This beautiful image (from APOD) looks like the trail of the ejected pulsar is illuminating a ball of gas and dust. My eye sees patches of light and shadow, but sometimes images can be deceptive. What ...
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Brightest Radio Source In the Universe
I would have assumed that the brightest radio source in the Universe is a quasar of some kind (perhaps 3C 273) given that the average pulsar has luminosity of $~10^{40} \text{Watts}$ and this is the ...
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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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Pulsars: How do astronomers measure minute changes in period (~picoseconds per year)?
I've been to some talks that mention how stable the period of a millisecond pulsar is over long periods of time. Recently, it was mentioned that astronomers have calculated the change in period over ...
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How do I make a custom pulsar map?
I'm looking to make a custom pulsar map like the one on the Voyager Records, but for an arbitrary location within the Milky Way Galaxy. I'm not even sure where to begin.
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How long would we survive an approaching neutron star?
I recently came across PSR B1620−26. A neutron star that captured a sun like star with an orbiting planet. The system went through several stages of development, but through it all the orbiting planet ...
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Hulse Taylor Binary Pulsar - How is "Cumulative Periastron Time shift" calculated?
Following on from a previous question about the interesting Hulse Taylor Binary Pulsar.
BACKGROUD
Weisberg & Taylor, 2004 present a graph showing the change in "Cumulative Periastron Time Shift" ...
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Acronyms in astrophysics: is there a place that collects them all anywhere on the internet? And what does PSN mean on the TNS server?
Acronyms in astrophysics: is there a place that collects them all anywhere on the internet? And what does PSN mean on the TNS server?
Is it "possible supernova" or "pulsar" ...
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Could pulsar navigation replace GPS
as a follow-up to my previous question I found out that the Voyager Golden record uses a star map of pulsars to precisely show where our solar system is...
Is it possible/feasible to base a ...
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Hulse-Taylor binary pulsar - what is the rate of mass/energy loss from the source?
Following on from an earlier question about the very interesting Hulse-Taylor binary pulsar. The high-frequency (radio) beam from the spinning pulsar sweeps across Earth about 17 times per second. ...
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I was finding the period of crab pulsar using efsearch(xronos)
I was finding the period of crab pulsar(one orbit data from ASTROSAT/laxpc) using efsearch (heasarc/xronos). Despite considering period = 33ms, I am not getting sharp peaks at higher Resolution for ...
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Is there a Vela Nebula?
The Vela pulsar is a neutron star from a supernova that exploded 10,000 years ago. It spins 11 times a second. The Crab Nebula along with the central Crab Pulsar formed 1000 years ago. This pulsar ...
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What exactly is "the rotating lighthouse model" in the context of a double pulsar?
The introduction to Testing the rotating lighthouse model with the double pulsar system PSR J0737-3039A/B (open access) says:
The double pulsar system PSR J0737-3039A/B was discovered by Burgay et al....
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How are pulsars detected from Earth?
This paper on Arxiv indicates that the signal period of known pulsars is 1 ms-15 s (0.07-1,000 Hz since F=1/T). I have an EE background and it's a long story how I ended up here, but suffice it to say ...
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How to find period of a pulsar from a given time sampled voltage data?
I've a data file with 2 columns, each containing time sampled voltage output (a sequence of real numbers) from a radio telescope, so there is a pair of telescope which are measuring the signal here. ...
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