A search for ionized jets towards massive young stellar objects
A search for ionized jets towards massive young stellar objects
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寻找射向大质量年轻恒星的电离喷流
DOI：
10.1093/mnras/stw1027
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发表时间：
2016
影响因子：
4.8
通讯作者：
Purser S
中科院分区：
文献类型：
--
作者：
Purser S
使用澳大利亚望远镜紧凑阵列在5.5、9.0、17.0和22.8千兆赫进行的无线电连续观测探测到了与49个大质量年轻恒星天体和Hiiregions中的45个有关的自由发射。其中，26个源被归类为电离喷流（其中12个是候选者），2个为模糊喷流或盘风，1个为盘风，14个为Hiiregions，2个无法分类。电离喷流的分类依据是形态学、射电通量和光谱指数，并结合以前在其他波长的观测结果。射电光度和动量的比例与热光度以同样的方式低质量的喷流，表明一个共同的机制，在所有群众的喷流生产。在13个射流中，我们看到了相关的非热/光学薄波瓣，这些波瓣是由射流内部和/或工作表面处的冲击造成的。10个喷流在它们的叶中显示非热（同步辐射）光谱，平均光谱指数α = −0.55，与冲击中的费米加速一致。这表明存在磁场，与包含磁场的射流形成模型一致。由于平行射电喷流的产生与吸积过程有关，本文的结果支持盘介导吸积形成大质量恒星的图象，喷流阶段的上限约为6.5 × 104年。喷流中典型的质量损失率为1.4 × 10− 5 M yr− 1，相关的动量损失率约为（1-2）× 10− 2 M km s− 1 yr −1。
Radio continuum observations using the Australia telescope compact array at 5.5, 9.0, 17.0 and 22.8 GHz have detected free–free emission associated with 45 of 49 massive young stellar objects and Hiiregions. Of these, 26 sources are classified as ionized jets (12 of which are candidates), 2 as ambiguous jets or disc winds, 1 as a disc-wind, 14 as Hiiregions and 2 were unable to be categorized. Classification as ionized jets is based upon morphology, radio flux and spectral index, in conjunction with previous observational results at other wavelengths. Radio luminosity and momentum are found to scale with bolometric luminosity in the same way as low-mass jets, indicating a common mechanism for jet production across all masses. In 13 of the jets, we see associated non-thermal/optically thin lobes resulting from shocks either internal to the jet and/or at working surfaces. 10 jets display non-thermal (synchrotron emission) spectra in their lobes, with an average spectral index of α = −0.55 consistent withFermiacceleration in shocks. This shows that magnetic fields are present, in agreement with models of jet formation incorporating magnetic fields. Since the production of collimated radio jets is associated with accretion processes, the results presented in this paper support the picture of disc-mediated accretion for the formation of massive stars with an upper limit on the jet phase lasting approximately 6.5 × 104yr. Typical mass-loss rates in the jet are found to be 1.4 × 10−5M⊙yr−1with associated momentum rates of the order of (1–2) × 10−2M⊙km s−1yr−1.
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影响因子：
6.5
作者：
J. Buizer;R. Redman;S. Longmore;J. Caswell;P. A. F. SOFIA-USRA;G. Observatory;Nrcc;U. Wales;Atnf
通讯作者：
J. Buizer;R. Redman;S. Longmore;J. Caswell;P. A. F. SOFIA-USRA;G. Observatory;Nrcc;U. Wales;Atnf
Herbig-Haro 物体的分子线发射模型
DOI：
10.1086/170777
发表时间：
1988
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
M. Wolfire;A. Konigl
通讯作者：
A. Konigl
与 OH 排放源相关的一类新型紧凑 H II 区域。
DOI：
10.1086/180116
发表时间：
1967
期刊：
The Astrophysical Journal
影响因子：
--
作者：
P. Mezger;W. Altenhoff;J. Schraml;B. Burke;E. Reifenstein;T. Wilson
通讯作者：
T. Wilson
Vela 分子脊云 D 中毫米级尘埃核的近红外和远红外对应物
影响因子：
6.5
作者：
M. Luca;T. Giannini;D. Lorenzetti;F. Massi;D. Elia;B. Nisini
通讯作者：
B. Nisini
影响因子：
4.9
作者：
HOLLENBACH, D;MCKEE, CF
通讯作者：
MCKEE, CF