A Galactic short gamma-ray burst as cause for the C-14 peak in AD 774/5

作者：Hambaryan V V^*; Neuhaeuser R

来源：Monthly Notices of the Royal Astronomical Society, 2013, 430(1): 32-36.

DOI：10.1093/mnras/sts378

• gamma-ray burst: general
• stars: neutron
• supernovae: general
• white dwarfs

In the last 3000 yr, one significant and rapid increase in the concentration of C-14 in tree rings was observed; it corresponds to a gamma- ray energy input of 7 x 10(24) erg at Earth within up to one year in AD 774/5. A normal supernova and a solar or stellar flare are unlikely as cause, so that the source remained unknown. Here, we show that a short gamma-ray burst (GRB) in our Galaxy is consistent with all observables: such an event is sufficiently short and provides the necessary energy in the relevant spectral range of gamma- rays. Its spectral hardness is consistent with the differential production rates of C-14 and Be-10 as observed. The absence of reports about a historic sighting of a supernova in AD 774/5 or a present-day supernova remnant is also consistent with a short GRB. We estimate the distance towards this short GRB to be similar to 1-4 kpc - sufficiently far away, so that no extinction event on Earth was triggered. This is the first evidence for a short GRB in our Galaxy.

• 出版日期2013-3