美国说朝鲜测试是核试验

在一个非常简短的陈述, the Director of the National Intelligence Office announced that the United States has confirmed that North Korea’s large explosion last week was nuclear. How do they know and why did it take them so long to confirm?

显然，朝鲜人提前宣布了对中国人和俄罗斯人的测试，但第一个物理证据表明朝鲜发生了一些事情，这表明爆炸次数很大。（某些地震记录站由综合测试禁令条约办公室运营，旨在验证符合综合测试禁令条约，该条约尚未获得美国的批准。）地震数据表示相当小的测试（通过核标准），不到一公斤，大概只有半千顿。一些Reports引用高达200吨。

当我们得到半吨,500吨s, of high explosive (specifically TNT) equivalent, then it is technically conceivable that the explosion could have actually been conventional, not nuclear. Given the North Korean penchant for bluff, could they have actually set off half a kiloton of conventional explosives? The United States is planning a conventional test,神圣的曲子，这将模拟核作用，它将超过700吨硝酸铵和燃油爆炸性，相当于近600吨TNT。半拖车的卡车可以携带25吨货物，因此，迪瓦斯特（Devine Strake）的700吨（远远足以模拟朝鲜测试）将是35辆卡车。这是硝酸铵的很多，但不是那种必然会在监视朝鲜的情报分析师中跳出来的活动。地震信号可以将爆炸与小地震区分开，但无法分辨常规爆炸和核爆炸之间的差异。所以朝鲜本来可以伪造它的。

This explanation seems increasingly unlikely in light of recent reports that radioactivity consistent with a nuclear weapon has been detected downwind of the North Korean test site. This could nail the test as nuclear. It is not easy to密封核爆炸而且我们甚至都不知道朝鲜人的努力。如果他们想最大程度地减少放射性排气性，他们将用土壤或粘土的回填将隧道塞满，并可能包括混凝土屏障。这些可能在测试期间破裂或泄漏。如果发生这种情况，那么大量的放射性材料可能已经将其弄清楚了，并且可以被发现。除泄漏外，还有渗漏。即使成功地立即进行了测试密封，气体也可能通过多孔岩石或岩石裂缝渗出。根据我的朝鲜地质地图，报告的测试地点位于花岗岩中。花岗岩不可渗透，但气体可能会因难以检测的裂缝而泄漏。

After the test, air samples taken down wind could be collected, returned to a laboratory and tested for even tiny traces of radioactivity. A leak would result in many telltale radioactive particles that would even give us some information about the design of the bomb. A seep most likely would give much less information, since the sample might be largely limited to gases, like xenon-133 with a five day half life. Xenon-133 might come from a nuclear fuel reprocessing facility. If that possibility could be eliminated, then a nuclear test is the most plausible remaining explanation. The DNI statement gave no details, referring simply to radioactive debris.

政府中的匿名消息来源显然已经报告那个炸弹是p。我没有特殊的内部信息，所以我只能推测，但这可能意味着有泄漏，没有渗漏，我们得到了一个很好的放射性样本。（《纽约时报》文章的另一点，使用p plut悔表明北朝鲜铀富集计划没有开发，很难理解。其铀富集计划的高度先进状态。）