Pulsars Definition and 31 Threads

I’m trying to understand the Hellings and Downs curve that is being used to argue for the existence of a gravitational wave background ([NANOGrav article][1]). How can it be that the angle between two pulsars is the only variable that determines if the gravitational waves will interfere...

I was listening to a Star Date podcast regarding the constellation Vulpecula and learned about the discovery of pulsars and neutron stars. https://stardate.org/radio/program/2023-03-19 The first neutron star was discovered in Vulpecula in 1967. https://en.wikipedia.org/wiki/PSR_B1919+21 In...

Hello All Dame Jocelyn Bell Burnell (the lady who was robbed of the Nobel Prize) described Pulsars to be like lighthouses, emitting a beam of high intensity light modulated by their spin, which we see as they 'flash' towards us. Would we only see the beam as pulses if the Pulsar was spinning...

I have a sci-fi idea regarding being able to move planets around like billiard balls. I'm theorizing that, after a nova, some of the bands of material around a star formed a new ring of rocky planets around a Neutron Star. Naturally, these are bathed in radiation. Having never taken high...

World's largest radiotelescope just completed. http://news.xinhuanet.com/english/2016-07/03/c_135485643.htm

Now kindly pardon my ignorance but I hope one of you can explain to me how this can be possible. A rotating neutron star or pulsar have been observed to spin at between 10 to 700 times per second. Now before I proceed further I like to draw your memories back to the merry go round we played as...

Hi everyone. I'm trying to derive the formula for the characteristic age of a pulsar. What I'm starting with is the following differential equation. dP/dt=K*P2-n What i think is odd, is several places they say solving this differential equation gives the following solution...

Hi everyone, The charged particles in the magnetic field around the neuton star, is accelerated along the magnetic field lines, which would go in a curve, from the north pole to the south pole. Due to the acceleration the particles will emit radiation, along their movement axis, and because the...

Hi everybody, I hope some of you have worked with pulsars before or other x-ray data from NASA Heasarc. I need some data showing a very precise light curve of the crab pulsar and some other pulsar. It should be something like this: http://cdn.eso.org/images/screen/eso9948i.jpg Where the time...

Is this phenomenon explicable with the simple laws of electromagnetism alone?

Dear PF Forum, I've read the current Featured Thread in November 12nd, Lost in the Milky Way scenario. It's a good thread. But I want know what pulsar is. https://en.wikipedia.org/wiki/Pulsar A. Does pulsar(s) have unique frequency? Given the number of pulsar in our galaxy and the vast range of...

Assuming a neutron star is a uniformly dense sphere of radius 10km and mass =1.4 mass of sun, derive the period of radial oscillations.First use hydrostatic equilibrium to calculate p, then the velocity of sound is $$v= \sqrt{ \gamma p / \rho}$$, so the period of pulsation is time it takes from...

Do neutron star, pulsars, magnetars etc. have solar flares like the sun or do they have sun spots like the sun or do they have solar winds and if they do have any of those types of weather, what are they called?

I'm slightly confused as to why and how we record "sounds" from space using radio-waves. Take for example, objects like pulsars on this website: http://www.jb.man.ac.uk/pulsar/Education/Sounds/ So do pulsars really sound like this? Do they actually produce a knocking/ticking sound? Or are these...

I've gotten a bit confused about the creation of the neutron star/pulsar, so I was hoping someone could point me in the right direction :) As fusion stops, when reaching the iron phase, the outer layers (hydrogen, helium, carbon... etc.) gets pulled in-wards do to gravity. This creates a bounce...

Pulsars -- Rotating neutron star produces EM radiation? Hello, If a neutron star is composed of neutrons, which do not carry any electric charge then how it's rotation produces pulsars which are electromagnetic radiation? Thanks.

Hello, Does the Conservation of Angular Momentum have any relation to the rapid rotation of Pulsars? I've reasoned that the Angular Momentum of the "parent" star would be concentrated on the smaller pulsar and would produce a greater frequency of rotation. Thanks,

Hello everybody. I am searching for an explanation about the beamed emission of pulsars, either in radio and in X-rays bands. I can not find a "standard" reason (with demonstration, eventually) for the beaming of this objects' radiation. Please, can you suggest to me something, or even a link...

And if so, what is the limit? Some pulsars spin very fast. more than 700 times per second, or even faster? So the centrifugal force would be very strong at the equator, threatening to rip them apart. Is there a limit on how fast a pulsar can spin before the centrifugal force would...

Please excuse the lay question; I'm not an astrophysicist nor do I study it accademically, but it interests me is all. I have a question about pulsars that I've tried to research via google, but the results I'm getting are very heavy, accademic texts. So, I'm hoping someone here could...

Intuitively I would say no because it seems like a big call but at the same time the high energy effects rely on the interaction between magnetic fields and gas don't they? Any tips or just an idea of where I can find out would be awesome

looking at my notes on pulsars I have: K=\frac{2\pi^{2}I}{P^{2}}\implies dk=\frac{2\pi^{2}I}{P^{2}}dP\implies\frac{dk}{dt}=\frac{-4\pi^{2}I}{P^{3}}\frac{dP}{dt} where K is kinetic rotational energy and P is momentum... I don't quite follow the final expression (when the time derivitive...

I know that pulsars are Neutron stars that emit their energy through their poles, bit why do they emit it through their poles, and not their sides? And Quasars, I though that all mater that falls into a black hole never escapes, so how do we see the...''stuff'' leaving it?

The pole still has extremely strong gravity, how can a sphere suddenly concentrate the radiation at the pole to be emitted there ? As this is the only exit, should there not be a strong deformation ? How does the radiation make it to the pole, or, is the radiation we are getting only from...

Ever wondered what it is like to make a major discovery in astrophysics? You may be interested in reading Jocelyn Bell Burnell's account of how she discovered pulsars as a postgraduate: http://www3.interscience.wiley.com/cgi-bin/fulltext/118807400/PDFSTART. BTW, - Jocelyn is too gracious to...

Ok two questions for all u smart people out there: 1. What is the difference between a pulsar and a brown dwarf? are brown dwarves just dead white dwarves? 2. M45. A cluster of blue giants in the sky. Are they actually close relative to each other like our sun and Sirius or Alpha Centauri...

...but they just didn't call it such. :rolleyes: Interesting story: http://scienceblogs.com/catdynamics/2007/08/schisler.php

have such stars been observed by the astrophysicists? and if they haven't yet, are they predicted by the current model of neutron stars physics and evolution?

hi just wondering if anyone knows some interesting things about binary pulsars in relation to general relativity. i have to give a short presentation on the topic and need some ideas on what to talk about thanks in advance

Originally posted in College Level Homework help but I got no responses there. Please help if you can. I am studying for my qualifier and doing problems out of Jackson. I am stuck on this one... any help would really be appreciated... I am unsure how to begin: Jackson 7.15 The partially...

why can't we use nanosecond pulsars to gauge expansion of universe? even if they are irregular ,if the "tendancy "of pulses measured in a second is always downward then at least it would be a partial proof.