An unusual supernova in the error box of the γ-ray burst of 25 April 1998
An unusual supernova in the error box of the γ-ray burst of 25 April 1998
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作者：
Galama, TJ;Vreeswijk, PM;Ianna, P
与 X 射线 (1)、光学 (2) 和无线电 (3) 波长的伽马射线爆发相关的余辉的发现以及对其中一些事件的红移的测量 (4,5) 已经确定伽马射线爆发位于极远的距离，使它们成为宇宙中已知的最强大的光子发射体。在这里，我们报告了在伽马射线暴GRB980425的误差框中发现的瞬态光发射，其Mras的光曲线与之前与伽马射线暴相关的光学余辉的光曲线非常不同。光学瞬变位于星系 ES0184-G82 的旋臂中，其红移速度仅为 2,550 km s(-1)（参考文献 6）。它的光谱和位置表明它是一颗非常明亮的超新星(7)，已被识别为SN1998bw。如果这颗超新星和 GRB980425 确实相关，那么伽马射线辐射的能量至少比其他伽马射线爆发低四个数量级，尽管它的外观在其他方面并不引人注目：这表明非常不同的机制可以产生伽马射线爆发。但与这种关联无关，超新星本身是不寻常的，在射电波长下表现出不寻常的光曲线，这要求发射射电光子的气体相对论性膨胀(8,9)。
The discovery of afterglows associated with gamma-ray bursts at X-ray(1), optical(2) and radio(3) wavelengths and the measurement of the redshifts of some of these events(4,5) has established that gamma-ray bursts lie at extreme distances, making them the most powerful photon-emitters known in the Universe. Here we report the discovery of transient optical emission in the error box of the gamma-ray burst GRB980425, the Light curve of which Mras very different from that of previous optical afterglows associated with gamma-ray bursts. The optical transient is located in a spiral arm of the galaxy ES0184-G82, which has a redshift velocity of only 2,550 km s(-1) (ref, 6). Its optical spectrum and location indicate that it is a very luminous supernova(7), which has been identified as SN1998bw. If this supernova and GRB980425 are indeed associated, the energy radiated in gamma-rays is at least four orders of magnitude less than in other gamma-ray bursts, although its appearance was otherwise unremarkable: this indicates that very different mechanisms can give rise to gamma-ray bursts. But independent of this association, the supernova is itself unusual, exhibiting an unusual light curve at radio wavelengths that requires that the gas emitting the radio photons be expanding relativistically(8,9).