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Thread: Fermi speaks hazily about gamma rays

  1. #1
    Join Date
    Sep 2005
    Metrowest, Boston

    Question Fermi speaks hazily about gamma rays

    The Fermi telescope finds an unusual symmetry between a diffuse microwave haze known to exist in the WMAP data towards the galactic center, and an overlying gamma ray haze with the same distinct overlapping morphology in the same region of the sky. The authors, Gregory Dobler,Douglas P. Finkbeiner,Ilias Cholis,Tracy Slatyer, and Neil Weiner propose no present explanation for the puzzling superposition of the two datasets.


    They do imply that the superposition of the two datasets will suggest a new surprising effect in an upcoming paper. I'll take my best shot here and now. I'd say both data sets putatively originate in the chance alignment of a young supernova remnant towards the galactic center.Why?
    1. It is unlikely that a colossal supernova remnant could possibly occur in the denser starfields of the galactic center, and still maintain a roughly axisymmetric (~ spherical ) shape of that size after expanding for tens of thousands of years.
    2. Transfer of momentum to the galactic ISM would slow and disintegrate even a huge remnant before long due to the spiral motion of the galaxy which is at least Keplerian near the hub.
    3.Previous work in other posts has distinctly shown that supernova remnants carry sufficient kinetic energy to generate microwaves for centuries. This has been corroborated by the work of Eli Dwek at NASA Goddard, Greenbelt, MD.
    4. The question of how blackbody the microwaves from a remnant can be has been a justifiable source of continual conundrum,raised by several authors, but is looking towards a novel approach with the study of late phase evolution of type 2 supernovae by Dr. Katherine Kielty of Rice U. According to her thesis, late phase type 2's contain the "blackest of blacks", carbon nanotubes. Black absorbers become black-body emitters at low temperatures, and that's in the microwave region.
    SEE: 2003 Phd Theses Blast Waves etc. SEE:
    SEE: post #4
    5. Inside the expanding supernova shock, the same synchrotron electrons contribute the haze of hard gammas which diffuse slowly out through the diffuse shell. This is what Fermi sees as a gamma haze in the shape of a shell.
    6. WMAP, tuned to different frequencies, sees the diffuse microwave haze from the nanotubes.
    7. The supernova remnant we live in, the Local Bubble, does the same thing, spraying us with a constant rain of cosmic rays, a trace of gammas, and x-rays, and our outer nanotube-coated dust grain diffuse shell peppers us with a constant whisper of microwaves that is the primary signal seen by WMAP, except from the inside of the bubble.
    Last edited by trinitree88; 2009-Oct-27 at 11:36 PM. Reason: link, authors

  2. #2
    Join Date
    Mar 2008
    I believe they are chasing after a neutralino self destruction scenario. The Fermi scientist suggest exercising reserve in this regard. While it fits in with the recent ideas about Dark Matter destruction, other ideas may be considered as well. They seem to think it is too wide ranged to be due to just one or more supernovae and the energy may not match.

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