During their violent merger, two neutron stars can shed a few percent of their mass. As this ejecta expands, it collides with the surrounding interstellar gas, producing a slowly fading radio flare that lasts for years. Radio flares uniquely probe the neutron star merger populations as many events from past decades could still be detectable. Nonetheless, no radio flare observation has been reported to date. Here we show that the radio transient FIRST J1419+3940, first observed in 1993 and still detectable, could have originated from a neutron star merger. We carry out numerical simulations of neutron star merger ejecta to demonstrate that the observed radio light curve is well reproduced by a merger model with astrophysically expected parameters. We examine the observed radio data, as well as the host galaxy, to find clues that could differentiate the transient’s neutron star merger origin from the alternative explanation—the afterglow of an off-axis long gamma-ray burst....

中文翻译：

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第一个J1419 + 3940，是中子星合并产生的第一个观测到的无线电耀斑

在激烈的合并中，两个中子星可能会掉落其质量的百分之几。随着这种喷射弹的膨胀，它会与周围的星际气体发生碰撞，产生持续多年的缓慢衰落的无线电弹。无线电耀斑独特地探测了中子星合并人口，因为过去几十年的许多事件仍然可以被发现。尽管如此，迄今为止尚无放射性火炬观测的报道。在这里，我们显示，1993年首次观察到并且仍然可以检测到的无线电瞬变FIRST J1419 + 3940可能源自中子星合并。我们对中子星合并射流进行了数值模拟，以证明观察到的无线电光曲线可以很好地被天体预期参数合并模型重现。我们检查观察到的无线电数据以及宿主星系，