卫星照片显示朝鲜在核试验场挖掘新坑道

North Korea appears to be digging a tunnel that could be used for a detonation at its main nuclear test site, according to new satellite photography analysis.

最新卫星照片分析显示，朝鲜正在其主要核试验场挖掘一条可用于引爆的新坑道。

Jeffrey Lewis, a prominent nuclear weapons analyst at the Monterey Institute of International Studies, said images from the past two months suggested work was under way on a fourth tunnel at the Punggye-ri site on the country’s east coast.

蒙特瑞国际研究学院(Monterey Institute of International Studies)的著名核武器分析专家杰弗里路易斯(Jeffrey Lewis)表示，过去两个月的卫星照片似乎表明，朝鲜正在其东海岸的丰溪里(Punggye-ri)核试验场建造第四条坑道。

North Korea has conducted three nuclear tests, in 2006, 2009 and 2013. Speculation has grown in recent months about a possible fourth test, which some had thought might come in October to mark the anniversary of foundation of the ruling Korean Workers’ party.

朝鲜于2006年、2009年和2013年进行了三次核试验。近几个月来，外界越来越担心朝鲜可能进行第四次核试验。有些人曾认为，核试验或许会在今年10月进行，配合朝鲜劳动党(Korean Workers’ Party)的成立周年庆祝。

In his analysis posted on the North Korea-focused 38 North website, Mr Lewis said there were no indications that a test was imminent but noted that it would add to Pyongyang’s “ability to conduct additional detonations at Punggye-ri over the coming years”.

路易斯在关注朝鲜的网站贴出的分析文章中表示，没有迹象表明朝鲜将马上进行核试验。但他指出，这将提高朝鲜“未来几年里在丰溪里进行更多核爆炸的能力”。

North Korea’s three previous tests suggested steady advances in nuclear technology. Academics at the University of Science and Technology of China estimated the yield of the 2013 test at about 12kT: more than double the force of its 2009 test and four-fifths that of the bomb dropped on Hiroshima in 1945.

此前三次试验似乎表明，朝鲜在核技术上取得了稳步进展。中国科学技术大学的学者们估计，2013年朝鲜核试验的当量约为1.2万吨——是2009年试验当量的两倍多，为1945年投到广岛的原子弹当量的五分之四。

Significantly, South Korean and US intelligence agencies see reason to believe North Korea’s claims that it has mastered the technology needed to produce a nuclear warhead small enough to be used with an intercontinental ballistic missile.

重要的是，韩国和美国的情报机构看到了相信朝鲜如下说法的理由：朝鲜已掌握了制造出可用于洲际弹道导弹的小型核弹头的技术。