# Pulsar's spectrum

1. Jul 18, 2012

### alialice

I know that pulsars have been discovered as radio sources. But ... where does the hypothetical black body spectrum of a neutron star peak? Does it emit more in radio or in X rays?
Thank you

2. Jul 18, 2012

### am_smbh

Although the first detected pulsars emitted in radio wavelengths, they have, subsequently, been found to emit in visible light, X-ray, and/or gamma ray wavelengths.

Your question might be read as a question about a neutron star temperature: well, the temperature inside a newly formed neutron star is from around $10^{11}$ to $10^{12}$ kelvin. However, the huge number of neutrinos it emits carries away so much energy that the temperature falls within a few years to around $10^{6}$ K. At this temperature, most of the light generated by a neutron star is in X-rays. Note that in visible light, neutron stars probably radiate approximately the same energy in all parts of visible spectrum, and therefore appear white.

The beam due to their rotation is expected to be in the radio spectrum: in fact we observe periodic-variability in the radio part of the electromagnetic spectrum.

I hope I studied well in order to answer your question correctly.

3. Jul 18, 2012

### alialice

Very good! Thank you for your answer! By the way, it seems like you're studying for an astronomy exam!