标题： IC 348中类木棕矮星的新候选体 显示英文标题

标题： New Candidates for Planetary-mass Brown Dwarfs in IC 348

摘要： 我们利用哈勃空间望远镜上的宽视场相机3拍摄的红外图像，寻找IC 348恒星形成团中的行星质量棕矮星。在这张图像中，我们已经识别出12个物体，它们的颜色表明光谱类型晚于M8型，对应于IC 348年龄时的质量小于等于30倍木星质量。 四个最亮的候选者已经通过光谱观测，所有这些都确认为晚期类型。 其中两个候选者似乎很年轻，因此很可能是这个星团的成员，而另外两个候选者的年龄和成员资格尚不确定。 其中一个先前的候选者是在消光校正后的Ks波段中已知的IC 348中最暗的成员，并且根据演化模型和假设年龄为3百万年的条件下，预计它的质量为4到5倍木星质量。 剩下的八个候选者中有四个具有地面光学数据进一步支持它们作为棕矮星的资格，其中一些比已知成员更暗（并且可能质量更低）。 显示英文摘要

摘要： We have used infrared images obtained with the Wide Field Camera 3 on board the Hubble Space Telescope to search for planetary-mass brown dwarfs in the star-forming cluster IC 348. In those images, we have identified 12 objects that have colors indicative of spectral types later than M8, corresponding to masses of <=30 Jupiter masses at the age of IC 348. The four brightest candidates have been observed with spectroscopy, all of which are confirmed to have late types. Two of those candidates appear to be young, and thus are likely members of the cluster, while the ages and membership of the other two candidates are uncertain. One of the former candidates is the faintest known member of IC 348 in extinction-corrected K_s and is expected to have a mass of 4-5 Jupiter masses based on evolutionary models and an assumed age of 3 Myr. Four of the remaining eight candidates have ground-based photometry that further supports their candidacy as brown dwarfs, some of which are fainter (and potentially less massive) than the known members.