A Possible Icy Kuiper Belt around HD 181327
A Possible Icy Kuiper Belt around HD 181327
复制标题
HD 181327 周围可能存在冰冷柯伊伯带
DOI：
10.1086/592567
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Paul S. Smith
中科院分区：
文献类型：
--
作者：
Christine H. Chen;M. Fitzgerald;Paul S. Smith
我们获得了HD 181327的Gemini South T-ReCS Qa波段（18.3 μm）图像和Spitzer MIPS SED模式观测。HD 181327是一个距今约1200万年的β Picture移动群的F5/F6 V成员。我们首次用热辐射解析了盘，发现盘的北方臂比南方臂亮1.4倍，另外，我们还在60-75 μm的Spitzer IRS和MIPS组合光谱中检测到一个宽峰，可能是由结晶水冰的辐射产生的。我们使用位于距离中心星星86.3 Au的无定形橄榄石和水冰粒的尺寸分布（dn/da a−2.25，amin与最小井喷尺寸一致，amax = 20 μm）来模拟IRS和MIPS数据，正如先前发表的散射光图像所观察到的那样。由于光解吸寿命为冰冷的粒子是~1400年，显着小于估计的~ 1200万年的年龄的系统，我们假设，我们已经检测到的碎片，可能是稳定的补充之间的碰撞冰冷的柯伊伯带对象的母体在一个新形成的行星系统。
We have obtained a Gemini South T-ReCS Qa-band (18.3 μm) image and a Spitzer MIPS SED-mode observation of HD 181327, an F5/F6 V member of the ~12 Myr old β Pictoris moving group. We resolve the disk in thermal emission for the first time and find that the northern arm of the disk is 1.4 times brighter than the southern arm. In addition, we detect a broad peak in the combined Spitzer IRS and MIPS spectra at 60-75 μm that may be produced by emission from crystalline water ice. We model the IRS and MIPS data using a size distribution of amorphous olivine and water ice grains (dn/da ∝ a−2.25, with amin consistent with the minimum blowout size and amax = 20 μm) located at a distance of 86.3 AU from the central star, as observed in previously published scattered-light images. Since the photodesorption lifetime for the icy particles is ~1400 yr, significantly less than the estimated ~12 Myr age of the system, we hypothesize that we have detected debris that may be steadily replenished by collisions among icy Kuiper Belt object-like parent bodies in a newly forming planetary system.