发现能量为10万亿电子伏特的宇宙射线的局部过量区域。

Discovery of localized regions of excess 10-TeV cosmic rays.

作者信息

Abdo A A, Allen B, Aune T, Berley D, Blaufuss E, Casanova S, Chen C, Dingus B L, Ellsworth R W, Fleysher L, Fleysher R, Gonzalez M M, Goodman J A, Hoffman C M, Hüntemeyer P H, Kolterman B E, Lansdell C P, Linnemann J T, McEnery J E, Mincer A I, Nemethy P, Noyes D, Pretz J, Ryan J M, Parkinson P M Saz, Shoup A, Sinnis G, Smith A J, Sullivan G W, Vasileiou V, Walker G P, Williams D A, Yodh G B

机构信息

Naval Research Laboratory, Washington, DC, USA.

出版信息

Phys Rev Lett. 2008 Nov 28;101(22):221101. doi: 10.1103/PhysRevLett.101.221101. Epub 2008 Nov 24.

DOI:10.1103/PhysRevLett.101.221101

PMID:19113471

Abstract

The 7 year data set of the Milagro TeV observatory contains 2.2 x 10(11) events of which most are due to hadronic cosmic rays. These data are searched for evidence of intermediate scale structure. Excess emission on angular scales of approximately 10 degrees has been found in two localized regions of unknown origin with greater than 12sigma significance. Both regions are inconsistent with pure gamma-ray emission with high confidence. One of the regions has a different energy spectrum than the isotropic cosmic-ray flux at a level of 4.6sigma, and it is consistent with hard spectrum protons with an exponential cutoff, with the most significant excess at approximately 10 TeV. Potential causes of these excesses are explored, but no compelling explanations are found.

摘要

米拉格罗 TeV 天文台的 7 年数据集包含 2.2×10¹¹ 个事件，其中大部分是强子宇宙射线所致。对这些数据进行搜索以寻找中等尺度结构的证据。在两个来源不明的局部区域发现了约 10 度角尺度上的过量发射，显著性大于 12σ。两个区域都高度置信地与纯伽马射线发射不一致。其中一个区域的能谱与各向同性宇宙射线通量不同，显著性水平为 4.6σ，并且与具有指数截断的硬谱质子一致，在约 10 TeV 处有最显著的过量。对这些过量的潜在原因进行了探讨，但未找到令人信服的解释。