Directivity and its energy dependence in solar flare energetic emission

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

12

Directivity, Fluence, Gamma Ray Astronomy, Particle Acceleration, Size Distribution, Solar Flares, Spectrum Analysis, Variations, X Ray Astronomy, Bremsstrahlung, Coulomb Collisions, Electron Beams, H Alpha Line, Solar Maximum Mission, Spectral Energy Distribution, Spectrometers, Venera Satellites

Scientific paper

We have studied 72 solar flares simultaneously observed by the Gamma-Ray Spectrometer (GRS, 0.3-1 MeV) and the Hard X-Ray Burst Spectrometer (HXRBS, 30-500 keV) on the Solar Maximum Mission (SMM). Using the spectral analysis results, we studied spectal and size distribution center-to-limb variations for both instruments. The GRS observations show significant center-to-limb variations in both spectral and size distributions, while HXRBS observations show insignificant variations. In general, the GRS spectra are harder than the HXRBS spectra, and their difference increases from center to limb, suggesting that a flattening of the spectrum above 300 keV is inevitable for the gamma-ray emissions. We corrected for the effect of spacecraft pointing and combined HXRBS and GRS data to obtain spectra over the energy range of 0.03-1 MeV. The fluences at various energies were calculated and normalized to the total fluence of the burst to measure the directivity. It is found that the directivity increases with increasing energy, from 1.1 at 50 keV to 6.5 at 1 MeV. These results are consistent with anisotropic electron beams and the physics of Coulomb collision and bremsstrahlung.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Directivity and its energy dependence in solar flare energetic emission does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Directivity and its energy dependence in solar flare energetic emission, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Directivity and its energy dependence in solar flare energetic emission will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1828828

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.