Questions tagged [pulsar]

Questions regarding neutron stars which emit regular pulses of electromagnetic radiation.

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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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6 votes
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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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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 are the typical density and temperatures in Pulsar Wind Nebulae?

What are the typical density and temperatures in Pulsar Wind Nebulae? Also, how do we typically observe/estimate these values?
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Did a watch company really try to sue radio astronomers for using the word "pulsar"? If so, which astronomers?

After about 48:37 in the really wonderful video Jocelyn Bell Burnell Special Public Lecture: The Discovery of Pulsars (linked below) Dr. Bell Burnell describes the ...
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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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Is the smaller companion of Pulsar J0453+1559 still the smallest known neutron star? Was it further confirmed to be a NS after Martinez et al. (2015)?

@ProfRob's Physics SE answer to What is the theoretical lower mass limit for a gravitationally stable neutron star? was linked just now in their answer to Can a neutron star ever be less than about 1....
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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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Pulsar signal periodicity detection algorithms?

I am currently working on pulsar signal periodicity detection. Most of the algorithm or paper which i read they use FFT (Fast Fourier Transform) and FFA (Fast Folding Algorithm ). Do we have any other ...
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How is the polar angle of a pulsar beam determined?

I just read the question "What is a typical polar angle of a pulsar beam?" and I was surprised that it had an answer. I thought there was little real information besides the timing of the ...
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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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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 is superradiance?

What is superradiance? I came across this term recently (used widely to explain fast radio bursts). After googling a bit, what I understand is: When several atoms are confined in a very small area and ...
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Why do some pulsar planets have designations with a capital letter at the end?

The pulsar PSR B1257+12 has three planets. Most triple-planet system have designation foo b, foo c, and foo d. However, I noticed that the three planets of this pulsar (PSR B1257+12) have a ...
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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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2 votes
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Can a pulsar also be a magnetar?

I know this is a simplistic question, but I cannot find a straight answer... Also, is it possible most or all neutron stars are magnetars and/or pulsars? It's just hard to see all of their properties ...
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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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Convert pulsar data to sound

I have a filterbank data (say name.fil) which I have dedispersed and stored into name.dat file using PRESTO. May I ask for detailed steps and explanation on how to convert that data to sound?
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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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9 votes
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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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How to determine arrival time delay given dispersion measure?

In an online textbook, the following formula is given to calculate the arrival time delay between two frequencies, $v_1, v_2$ in a dispersed radio pulse: $$t_1 - t_2 = 4.15 \cdot DM [(v_1/\text{GHz})^{...
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16 votes
2 answers
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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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3 answers
372 views

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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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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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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13 votes
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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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20 votes
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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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6 votes
2 answers
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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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1 vote
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Why pulsar pulses are so extremely regular?

It's often said that the pulses of the pulsar have a very precise period, which helps to detect easily exoplanets that cause fluctuations in the time of arrival (TOA) of the pulses. Anybody knows why?
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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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21 votes
1 answer
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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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10 votes
1 answer
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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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3 votes
0 answers
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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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6 votes
1 answer
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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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3 votes
1 answer
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How do I calculate Allan Variance (maybe for pulsars)?

I am studying pulsar timing this summer and have come across many Allan Deviation plots that include several popular clocks alongside pulsar measurements, like this one by N. Ashby and D.A. Howe: I ...
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2 votes
1 answer
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How do I download PSRCHIVE and Tempo2 for pulsar timing on Mac Mojave?

I am fairly new to pulsar astronomy, and I need to download PSRCHIVE and then Tempo2. I have followed the instructions online here: PulsarAstronomy.net I'm also pretty new to linux commands/Mac ...
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3 votes
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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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0 votes
1 answer
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Constant interval between pulses from all pulsars

It was found from the observations of the radiopulsars that the intervals between their pulses are changing periodically, besides, for all pulsars this period is the same and equal to one stellar (...
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1 vote
1 answer
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How to improve efficiency in periodicity detection?

Our data set has $10^4$ data points, but has a long baseline and many gaps. If we bin the data, there would be $10^8$ data points ($[t,\rm {value}]$), but only about 1% are non-zero values. How to ...
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6 votes
3 answers
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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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3 votes
1 answer
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Have any more "white dwarf pulsars" been discovered or searched for?

Back in 2016, Marsh et al. reported that the binary system AR Scorpii exhibits complex radio signals similar to those observed from traditional pulsars. In particular, pulsed synchrotron emission ...
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4 votes
2 answers
519 views

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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1 vote
3 answers
286 views

How much mass does our sun need for exploding like supernova?

Beside that, is that possible our sun became pulsar? And if not (and i know likely) but how much more mass does it need to become one ?
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1 vote
1 answer
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Why are the spherical and cartesian galactic coordinates in the ATNF Pulsar Catalogue different?

I am trying to relate Galactic Latitude (b) and Longitude (l) (spherical coordinates) to galactic cartesian x,y,z coordinates in the ATNF pulsar catalog. This query shows some sample data with ...
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6 votes
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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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3 votes
1 answer
538 views

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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1 vote
1 answer
181 views

Could a pulsar in orbit around a black hole feed the black hole with its radiation?

Could the black hole consume the radiation? If so, could the pulsar radiation absorbed by the black hole make it grow steadily more massive over the course of billions or trillions of years?
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2 votes
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What does a pulsar look like if viewed from above?

Have we ever seen a pulsar directly from above or below it's spin axis? I am wondering if a pulsar seen from this angle would appear to be constantly spinning or if it would just appear like a normal ...
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5 votes
2 answers
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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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