Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events

  title={Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events},
  author={Larissa M. Ejzak and Adrian L. Melott and Mikhail V. Medvedev and Brian C. Thomas},
  journal={The Astrophysical Journal},
Gamma-ray bursts (GRBs) directed at Earth from within a few kiloparsecs may have damaged the biosphere, primarily through changes in atmospheric chemistry that admit greatly increased solar UV. However, GRBs are highly variable in spectrum and duration. Recent observations indicate that short (~0.1 s) burst GRBs, which have harder spectra, may be sufficiently abundant at low redshift that they may offer an additional significant effect. A much longer timescale is associated with shock breakout… Expand

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