Kachelrieß M, Neronov A, Semikoz D V
Institutt for fysikk, NTNU, Trondheim, Norway.
Astronomy Department, University of Geneva, Chemin d'Ecogia 16, Versoix 1290, Switzerland.
Phys Rev Lett. 2015 Oct 30;115(18):181103. doi: 10.1103/PhysRevLett.115.181103. Epub 2015 Oct 29.
The locally observed cosmic ray spectrum has several puzzling features, such as the excess of positrons and antiprotons above ~20 GeV and the discrepancy in the slopes of the spectra of cosmic ray protons and heavier nuclei in the TeV-PeV energy range. We show that these features are consistently explained by a nearby source which was active approximately two million years ago and has injected (2-3)×10^{50} erg in cosmic rays. The transient nature of the source and its overall energy budget point to the supernova origin of this local cosmic ray source. The age of the supernova suggests that the local cosmic ray injection was produced by the same supernova that has deposited ^{60}Fe isotopes in the deep ocean crust.
当地观测到的宇宙射线谱有几个令人费解的特征，比如在约20 GeV以上正电子和反质子过量，以及在TeV - PeV能量范围内宇宙射线质子和重核谱斜率的差异。我们表明，这些特征可以由一个大约两百万年前活跃的附近源持续解释，该源已在宇宙射线中注入了(2 - 3)×10^{50} 尔格的能量。该源的瞬变性质及其总能量预算指向这个本地宇宙射线源的超新星起源。超新星的年龄表明，本地宇宙射线注入是由在深海地壳中沉积了^{60}Fe同位素的同一颗超新星产生的。
