More phenomena difficult to observe

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More phenomena difficult to observe

• A MacKinnon

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More phenomena difficult to observe

• synchrotron radiation of positrons sub-mm
  observations?
• inner bremsstrahlung of secondary neutrons

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Positron energy distribution from ? decay
really, this is what is injected into the source
by colliding ps, ?s ?2, Tmax 3 GeV/nucl
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Effective distribution in thick target source
dE/dt collisions (logarithmic energy dependence
constant!) synchrotron (?2)
bremsstrahlung (? - above 100 MeV)
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Cumulative e distribution mean distribution
in source
divide these by dE/dt
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Synchrotron spectrum monoenergetic e
?c 4.3106 B ?2 sin?
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Synchrotron spectrum
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Rough estimate

• 1032 protons above 300 MeV
• 10-2 e per proton
• 410-22 1000 erg.s-1 .Hz-1
• 10-2 s lifetime
• spread out over e.g. 100 s and divided by 4 ? AU2
• 10-20 erg.cm-2.s-1 .Hz-1 10-23 W.m-2.Hz-1
  10-1 s.f.u.
• TOO SMALL

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Inner Bremsstrahlung spectrum
Knipp and Uhlenbeck (1936) Bloch (1936)
Petrosian and Ramaty (1972)
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Angular distribution of IBXRs
r solar distance z distance from
Earth distances in AU
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Briefly

• X-ray flux integrates over all neutron energies
  present along the line of sight
• looking further from the Sun samples more
  energetic neutrons because lower energy ones
  decay
• Approximately, the distribution of X-ray flux
  with angle is the Laplace transform of the
  neutron energy distribution at the Sun
• invert integral equation to deduce neutron energy
  distribution F(E)

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Example
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Suns X-ray halo
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Seckel et al. (1992)

• modelled turbulent transport of cosmic rays in
  inner heliosphere interaction with small-scale
  magnetic fields near solar surface (lots of
  assumptions!)
• predicted 2.310-8 neutrons.cm-2.s-1 above 100
  MeV at 1 AU
• assume F(E)?(E10)-? at the Sun and normalise to
  this prediction
• ? IB flux at lt1 of cosmic XRB in 2 10 keV
  range

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After flares?

• look near large, limb flares..