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Supernovae GRB paper

  1. Oct 24, 2004 #1

    Chronos

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    Supernovae fans may find this of interest, I know I did:
    http://arxiv.org/abs/astro-ph/0402404
     
  2. jcsd
  3. Oct 25, 2004 #2
    The paper says that quark stars should be a mixture of up, down, and strange quarks. I wonder why is not permitted the presence of charm, top and bottom quarks
     
  4. Oct 25, 2004 #3

    selfAdjoint

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    Ordinary matter at ambient energies does not contain the c, t, and b quarks. Quark stars are theorized to be a late state of ordinary matter stars.
     
  5. Oct 26, 2004 #4
    Interesting the possibility of the existence of Hybrid neutron stars (neutron stars with a core composed of quark matter). It remembers me the Thorne-Zytkow object (a red giant with a neutron star inside). Spectacular if can exist the stellar russian nesting doll (I mean a red giant containing a neutron star and this containing a quark star)! :bugeye:
     
    Last edited: Oct 26, 2004
  6. Oct 27, 2004 #5
    So, I keep reading the article and then it's mentioned the fact that neutrinos are trapped in the interior of a newborn neutron star. This phenomenon is called neutrino trapping. What is the nature of this phenomenon? Neutrinos hardly interact with anything, how can they become trapped?
     
  7. Oct 27, 2004 #6

    Chronos

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    This has to do with what is referred to as the neutrino opacity temperature [~1MeV]. Neutrinos cannot escape from the stellar core above this temperature.
     
  8. Oct 27, 2004 #7

    Nereid

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    because ... ?

    Let me guess (no, I've not read the paper) ... it's much the same reason it takes 'light' millions (?) of years to escape from the core of the Sun ... the neutrinos can only travel a short distance before they collide (inverse beta?) with a proton/quark/whatever and are absorbed, to be re-emitted some short time later, in a direction that's random wrt the one they were originally travelling. Now how does this relate to temperature?
     
  9. Oct 28, 2004 #8

    Chronos

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  10. Oct 28, 2004 #9
    That's great. I've read a bit about all this stuff, and I've learned that the zone dividing the trapped neutrinos from those free to escape is called neutrinosphere
     
    Last edited: Oct 28, 2004
  11. Oct 30, 2004 #10
    on the site that Chronos mentioned above, i read the article and came across a part on neutron stars collapse. and that this would eventually lead to a blackhole.

    first the neutroinosphere. this would be caused not by temp. but pressure.

    this is because in a neutron star, neutrons are so mass less that they are the last to be crushed by gravity. gravity is, from a high energy plasmic point of view, is crushing matter to the state of pure energy( back to the point of plasmic energy,non-particle forms). which then the neutron gets absorbed back into this plasma energy form by absorption of its wave length. this because high energy plasma has within it all wave lengths that are known.

    some neutrinos escape in the proto phase of a neutron star,but in time of course this will lesson as gravity becomes stronger and therefore increases it's grasp on particles which have less and less mass.
     
  12. Oct 30, 2004 #11
    supplemental

    of course the temps; cause by the crushing by gravity, could not counter gravity because moving at only the speed of light couldn't escape. which would add to the internal pressure as well.
     
  13. Oct 30, 2004 #12
    in any blackhole, matter is crushed to the point of pure high energy plasma(non- particle form). this would be true in, dimension,space and time.therefore the blackhole would not loose any macro-characteristics.since dimension,space and time would collapse together. therefore at it's point of maximum singularity, being a high plasma energy state that is still in the particle form. as an increase in gravity pressure continues,it melds into the high energy plasma(non-particle form) and the pressure of gravity is pulled away by the flow of high energy plasma therefore relieving gravitational pressure and then the singularity disperses(with time), as the form of the singularity is absorbed.
     
  14. Oct 31, 2004 #13
    disperses here means,as the wave lengths present in the singularity are absorbed,the singularity it's self begins to decrease in it's form( from a 3D point) to 1/2, 1/4, 1/8.......etc. of the 3D form, until completely absorbed. which happens extremely quickly or instantaneously. depending on the strength of gravitational and other internal pressures and becomes again part of the line of a 3D filament of high energy plasma.(non-particle)
     
  15. Nov 1, 2004 #14
    http://xxx.lanl.gov/abs/astro-ph/0410728
    this appeared today. Is a unified model for short GRBs and long GRBs. According to this model, both kinds of GRBs arise from the same phenomenon (high energetic supernovae). The difference is that we are viewing the jet from different angles. I want to remind that the scientific consensus nowadays is that long and short GRBs arise from different phenomena
     
  16. Nov 1, 2004 #15
    define "DIFFERENT PHENOMENA"
     
  17. Nov 1, 2004 #16
    habitually was thought that long GRBs arise from hypernovae, and short GRBs from a different process (e.g. the collision of two neutron stars)
     
  18. Nov 1, 2004 #17
    as well, other states of matter(gas,liquid,solid) are elecrically neutral BUT high energy plasma is not. it has ALL wavelengths and i do mean ALL. it has wave lengths even beyond our ability to detect. it has, ALL phenomenon.
     
  19. Nov 1, 2004 #18
    in a hypernova, if i understand what your thinking here, is a star which had an imbalance. and the imbalance causes the star to implode. the explosion i suspect is the point of instance with which the balance was broken enough that instead of moving Out from the center of the galaxy, it is now moving in. this then sets up the building of a blackhole.

    in the collision of two neutron stars. to me at this point i cannot say wether short GRBs are not from the collision of two neutron stars. but i look at it this way. if two neutron stars collide, since they are of the same wavelength,
    they will meld into each other quietly(since they are on the same wave length no energy escapes but energy is absorbed). therefore no gamma rays produced. this then leads to WHAT are GRBs,of any length, and that leads to the study of Plasmas and Cosmic Plasmas.

    a couple of sites are; www.theuniverse.ws and www.plasma.org


    enjoy!!
     
  20. Nov 1, 2004 #19

    Nereid

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    north, thanks for your posts.

    However, and perhaps it's just me, but there seems to be considerable confusion in your posts ... For example, the collision of two neutron stars has been extensively modelled, and it does most certainly produce gammas, copious quantities of them. The key question is how well the gamma (and X-ray, and optical, and ...) signature matches the observed short (or long) GRBs (or not). Similarly, whether the short GRBs are merely the first, most violent, sign of a 'flare' on a magnetar can likewise be wrestled with by comparing the observed time and wavelength data against theoretical predictions (there are other tests too).

    Note that whether it's colliding neutron stars, hypernovae (or merely common supernovae), magnetars, .... in ALL cases it is plasmas which give rise to what we 'see' (exception: neutrino emission is due to processes that take place within nuclear material, and are only 'plasmas' to the extent that the term has been generalised to cover a completely different physical regime ... the 'quark-gluon plasma', for example).
     
  21. Nov 2, 2004 #20

    Garth

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    GRBs - May they be exploding primordial back holes a la Hawking?
    Garth
     
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