Dust Continuum Imaging of the HH 24 Region in L1630
Dust Continuum Imaging of the HH 24 Region in L1630
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L1630 中 HH 24 区域的尘埃连续体成像
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
R. Zylka
中科院分区：
文献类型：
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作者：
D. Lis;K. Menten;R. Zylka
利用IRAM 30 m望远镜的MPIR测辐射热计和加州理工学院亚毫米波天文台（CSO）的SHARC测辐射热计照相机，我们绘制了L1630中Herbig-Haro天体HH 22-HH 26周围区域的1300和350 μm连续辐射图，这是猎户座B分子云复合体的一部分。我们的观测揭示了在HH 24-HH 26周围区域存在一个至少由9个处于不同演化阶段的原恒星凝聚体组成的星团。除了两颗先前确认的0级原恒星外，还探测到另外两颗具有350/1300 μm低通量比的源。虽然远红外线通量的缺乏排除了确定其性质的可能性，但它们的低350/1300 μm通量比沿着以及没有嵌入的红外线和无线电连续源表明它们可能处于非常早期的演化阶段。特别是，这两个源之一在1300 μm的图像中显得相当紧凑，可能处于等温坍塌的短暂阶段。此外，我们还在HH 22-HH 23天体附近探测到了3毫米的连续源，包括HH 23光学喷流起源处的一个紧凑源。辐射热光度，亚毫米辐射热光度比，温度和质量的这个来源都是一致的0级原恒星。然而，源的紧凑性表明，连续辐射可能是由一个未解决的磁盘为主，将预期为一个更先进的原恒星源。在我们的CO、13 CO和HCO+数据中，没有发现与CSO相关的分子外流存在的证据。
We have mapped the 1300 and 350 μm continuum emission in the region surrounding the Herbig-Haro objects HH 22-HH 26 in L1630, which is part of the Orion B molecular cloud complex, using the MPIR bolometer at the IRAM 30 m telescope and the SHARC bolometer camera at the Caltech Submillimeter Observatory (CSO). Our observations reveal the presence of a cluster of at least nine protostellar condensations at various evolutionary stages in the region around HH 24-HH 26. In addition to two previously identified class 0 protostars, two additional sources with a low 350/1300 μm flux ratio are detected. Although the lack of far-infrared fluxes precludes a definitive determination of their nature, their low 350/1300 μm flux ratio along with the absence of embedded infrared and radio continuum sources suggests that they are likely to be in a very early evolutionary stage. In particular, one of these two sources appears quite compact in the 1300 μm image and may be in the short-lived phase of isothermal collapse. In addition, we have detected three millimeter continuum sources in the vicinity of the HH 22-HH 23 objects, including a compact source at the origin of the HH 23 optical jet. The bolometric luminosity, submillimeter-to-bolometric luminosity ratio, temperature, and mass of this source are all consistent with those of a class 0 protostar. However, the compactness of the source suggests that the continuum emission may be dominated by an unresolved disk, as would be expected for a more evolved protostellar source. No evidence is found for the presence of a molecular outflow associated with this source in our CO, 13CO, and HCO+ data obtained with the CSO.