Pulsars as cosmic ray sources

• Assuming Crab pulsar-like sources… can Galactic pulsars source CR electrons? Need to calculate how many electrons produced by the Crab nebula.

• Observed synchrotron X-rays from SNR, n ~10 Hz = 4 x 10 E B Hz assume B = 10 Tesla => E = 5 x 10 J = 3 x 10 eV

m

18

36

2

SNR

-8

e-

-6

13

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We are going to find out whether pulsar lie the Crab pulsar, can produced the observed levels of cosmic ray electron energy densities.

So first we have to calculate how many electrons the Crab pulsar actually produces. Stage one is to find out how much energy is in the electrons. At X-ray frequencies, nu_m~1e18 Hz, and this is equal to 4e36 E^2 B Hz (see the section on synchrotron emission).

Thus assuming a magnetic field for the supernova remnant of 1e-8 Tesla, we calculate an energy in the electrons of 5e-6 J, which is equivalent to 3e13eV.