1. More phenomena difficult to observe A MacKinnon

2. More phenomena difficult to observe synchrotron radiation of positrons: sub-mm observations? inner bremsstrahlung of secondary neutrons

3. Positron energy distribution from  + decay really, this is what is injected into the source by colliding p’s,  ’s  =2, T max = 3 GeV/nucl

4. Effective distribution in thick target source dE/dt : collisions (logarithmic energy dependence – constant!) synchrotron (  2 ) bremsstrahlung (  - above 100 MeV)

5. Cumulative e + distribution – ‘mean distribution’ in source divide these by dE/dt

6. Synchrotron spectrum – monoenergetic e c = 4.3×10 6 B  2 sin 

7. Synchrotron spectrum

8. Rough estimate 10 32 protons above 300 MeV × 10 -2 e + per proton  4×10 -22 1000 erg.s -1.Hz -1 × 10 -2 s lifetime spread out over e.g. 100 s and divided by 4  AU 2 ~ 10 -20 erg.cm -2.s -1.Hz -1 = 10 -23 W.m -2.Hz -1 = 10 -1 s.f.u. TOO SMALL

9. Inner Bremsstrahlung spectrum Knipp and Uhlenbeck (1936); Bloch (1936); Petrosian and Ramaty (1972)

10. Angular distribution of IBXR’s r = solar distance z = distance from Earth distances in AU

11. 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)

12. Example

13. Sun’s X-ray halo

14. 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 2.3×10 -8 neutrons.cm -2.s -1 above 100 MeV at 1 AU assume F(E)  (E+10) -  at the Sun and normalise to this prediction  IB flux at <1% of cosmic XRB in 2 – 10 keV range

15. After flares? look near large, limb flares……..