Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005, India.
Nat Commun. 2011 Feb 1;2:175. doi: 10.1038/ncomms1178.
The origin of ultra-high-energy cosmic rays (UHECRs) remains an enigma. They offer a window to new physics, including tests of physical laws at energies unattainable by terrestrial accelerators. They must be accelerated locally, otherwise, background radiations would severely suppress the flux of protons and nuclei, at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Nearby, gamma ray bursts (GRBs), hypernovae, active galactic nuclei and their flares have all been suggested and debated as possible sources. A local sub-population of type Ibc supernovae (SNe) with mildly relativistic outflows have been detected as sub-energetic GRBs, X-ray flashes and recently as radio afterglows without detected GRB counterparts. Here, we measure the size-magnetic field evolution, baryon loading and energetics, using the observed radio spectra of SN 2009bb. We place such engine-driven SNe above the Hillas line and establish that they can readily explain the post-GZK UHECRs.
超高能宇宙射线（UHECRs）的起源仍然是一个谜。它们为新物理提供了一个窗口，包括对地面加速器无法达到的能量的物理定律的检验。它们必须在本地加速，否则，背景辐射会严重抑制质子和原子核的通量，能量超过格雷森-扎采平-库兹明（GZK）极限。在附近，伽马射线暴（GRB）、超新星、活动星系核及其耀斑都被提议并争论为可能的来源。具有轻度相对论性外流的 Ibc 型超新星（SN）的局部亚种群已被检测为亚能伽马射线暴、X 射线闪光，最近还被检测为无线电余晖，而没有检测到伽马射线暴对应物。在这里，我们使用观测到的 SN 2009bb 的射电光谱来测量其大小-磁场演化、重子加载和能量学。我们将这种引擎驱动的超新星置于希拉斯线之上，并确定它们可以很容易地解释后 GZK UHECRs。
