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How can a magnetar exist?

  1. Mar 16, 2013 #1
    I'm confused how a magnetar could exist, given that the point of a neutron star is that electrons are compressed enough to combine with protons, thus leading to neutrons. If all the electrons were "used up" how could there be any currents, especially since neutrons can't conduct current anyways? Thanks for any answers
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  3. Mar 16, 2013 #2


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  4. Mar 16, 2013 #3
    I quote from wikipedia source you provided

    "Such stars are composed almost entirely of neutrons, which are subatomic particles without net electrical charge and with slightly larger mass than protons."
  5. Mar 16, 2013 #4


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    Read the "Structure" section in that same link.
  6. Mar 16, 2013 #5
    I don't much care for that Wiki page. That's just plain wrong. Neutron star crusts have plenty of nuclei and free electrons, and neutron star cores are a few percent protons and electrons. The cores are so dense that the density of charge carriers is extremely high, possibly the highest in the Universe.
  7. Mar 16, 2013 #6


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    I sure would like some reference(s) to better, more detailed, and more accurate descriptions of neutron stars. Would you please post some? Thank you.
  8. Mar 17, 2013 #7
    How detailed do you want? This book looks very good. It even has extracts posted online that covers the Outer Envelope and Envelopes with Strong Magnetic Fields.
  9. Mar 17, 2013 #8
    There's a magnatar page by the guy who originally proposed they exist. http://solomon.as.utexas.edu/~duncan/magnetar.html

    Now there's a real expert.
  10. Mar 19, 2013 #9
    Neutron stars structure is highly composite, in fact for the core of pulsars like magnetars is yet more or less unknown.

    Neutron stars have an atmosphere of almost electron and plasma gas (sometimes liquid), that even if few cm thick can generate great magnetic field, having plasmon resonances and so on and a rich spectrum... So here you have electrons and finite nuclei (with protons and neutrons)

    Then the crust of the neutron star can be divided into outer and inner crust. The outer crust is roughly half a km wide ad made mostly of a lattice of completely polarized finite nuclei. Usally (but not always) neutron rich. But you have again the same order of magnitude of protons and neutrons.

    The inner crust runs deep for a couple of km and it is made mostly by a sea of neutrons but have a lot of proton "impurities" that condense to form bulges of protons. The ratio is about 50 condensed protons to 1000 of neutrons in most models.

    Then you have the core, divided in
    outer core, 4/5 km deep, made by neutrons, but again not so few protons created by the neutrino emission for cooling of the stars toghether with muons
    and the misterious inner core, also approx 5 km deep, with a still unknown composition, but always with some charged material in the center: in most models toghether with p and n exotic baryons such as hyperions, but also condensed pions, kaons or even free quarks.

    Above all, take into account that the neutron star is a very dynamic environment, like in a star there are a lot of nuclear reactions going on, mostly because it have to find ingenuous way to cool itself, but in such a system also weak force-based reactions are feasible and so the components, and even their charge (due to the weak-force driven reactions), change dynamically.
  11. Mar 19, 2013 #10
  12. Mar 20, 2013 #11
    Where might I learn more about this?
  13. Mar 20, 2013 #12
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