Filament L1482 in the California molecular cloud
Filament L1482 in the California molecular cloud
复制标题
加州分子云中的细丝 L1482
DOI：
10.1051/0004-6361/201323122
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发表时间：
2014-05
影响因子：
6.5
通讯作者：
He, Y. X.
中科院分区：
文献类型：
--
作者：
Lou, Y. -Q.;Wu, G.;Tang, X. D.;He, Y. X.
目标。结合几个互补的观测和物理估算，研究了加州分子云L1482分子丝的引力碎裂过程。我们研究了这种分子细丝的运动学和动力学状态以及嵌入其中的几十个致密分子团的物理性质。方法.我们提出并比较了分子线发射观测的J = 2− 1和J = 3− 2跃迁的12 CO在这个分子复合物，使用科尔纳天文台的亚毫米天文学（KOSMA）3米望远镜。这些观测得到了中国西部青海省德令哈站紫金山天文台（PMO）13.7米射电望远镜获得的13 CO J = 1− 0发射的档案数据观测和分析，以及赫歇尔太空望远镜在线档案中的红外发射图的补充，SPIRE和PACS相机获得。这些互补数据集的比较允许L1482分子细丝的全面多波长分析。结果在加州分子云中，我们已经沿着分子丝L148 2确定了23个团簇。对于这些分子团，我们能够估计列和数量密度，质量和半径。这些团块的质量范围为6.8 - 62.8 M <$，平均值为24.7 + 31.1 - 16.2 M <$。其中11个分子团似乎与原恒星共生，因此被称为原恒星团。原恒星团块和我们样本中剩下的无星团块似乎具有相似的温度和线宽，但平均而言，原恒星团块似乎比后者质量稍大。所有这些分子团都表现出超音速的非热气体运动。虽然在质量和大小上与更为人所知的猎户座分子云惊人地相似，但基于静态Bonnor-Ebert球得出的质量半径阈值，与猎户座分子云相比，加州分子云中高质量恒星的形成速率似乎受到抑制。沿着沿着L1482分子云的12 CO J = 2− 1的视向速度基本上是一致的，这表明它是一个大体上相干的对流结构。由于NGC 1579星团位于两个分子细丝的交界处，因此NGC 1579星团的起源可能是由对流流入物供给的合并分子细丝。我们的分析表明，这些分子丝是热超临界的，分子团可能通过重力破碎沿丝沿着形成。这些分子团不是静态的，而是很可能处于动态演化过程中。
Aims. The process of gravitational fragmentation in the L1482 molecular filament of the California molecular cloud is studied by combining several complementary observations and physical estimates. We investigate the kinematic and dynamical states of this molecular filament and physical properties of several dozen s of dense molecular clumps embedded therein. Methods. We present and compare molecular line emission observations of the J = 2− 1 and J = 3− 2 transitions of 12 CO in this molecular complex, using the Kolner Observatorium fur Sub-Millimeter Astronomie (KOSMA) 3-meter telescope. These observations are complemented with archival data observations and analyses of the 13 CO J = 1− 0 emission obtained at the Purple Mountain Observatory (PMO) 13.7-meter radio telescope at Delingha Station in QingHai Province of west China, as well as infrared emission maps from the Herschel Space Telescope online archive, obtained with the SPIRE and PACS cameras. Comparison of these complementary datasets allows for a comprehensive multiwavelength analysis of the L1482 molecular filament. Results. We have identified 23 clumps along the molecular filament L148 2 in the California molecular cloud. For these molecular clumps, we were able to estimate column and number densities, masses, and radii. The masses of these clumps range from∼ 6.8 to 62.8M⊙ with an average value of 24.7 +31.1 −16.2 M⊙. Eleven of the identified molecular clumps appear to be assoc iated with protostars and are thus referred to as protostellar clumps. Protostell ar clumps and the remaining starless clumps of our sample appear to have similar temperatures and linewidths, yet on average, the protostellar clumps appear to be slightly more massive than the latter. All these molecular clumps show supersonic nonthermal gas motions. While surprisingly similar in mass and size to the much better known Orion molecular cloud, the formation rate of high-mass stars appears to be suppressed in the California molecular cloud compared with that in the Orion molecular cloud based on the mass-radius threshold derived from the static Bonnor-Ebert sphere. The largely uniform 12 CO J = 2− 1 line-of-sight velocities along the L1482 molecular cloud shows that it is a generally coherent filamentary structure. Since the NGC1579 stellar cluster is at the junction of two molecular filaments, the origin of the N GC1579 stellar cluster might be merging molecular filaments fed by c onverging inflows. Our analysis suggests that these molecul ar filaments are thermally supercritical and molecular clumps may form by gravitational fragmentation along the filament. Instead o f being static, these molecular clumps are most likely in processes of dynamic evolution.
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DOI：
10.1088/0004-637x/772/2/100
发表时间：
2013-06
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Katherine I. Lee;L. Looney;S. Schnee;Zhi-Yun Li
通讯作者：
Katherine I. Lee;L. Looney;S. Schnee;Zhi-Yun Li
DOI：
--
发表时间：
2010
期刊：
--
影响因子：
--
作者：
A. Poglitsch;C. Waelkens;N. Geis;H. Feuchtgruber;B. Vandenbussche;L. Rodriguez;O. Krause;E. Renotte-E
通讯作者：
A. Poglitsch;C. Waelkens;N. Geis;H. Feuchtgruber;B. Vandenbussche;L. Rodriguez;O. Krause;E. Renotte-E
DOI：
10.1088/0004-637x/761/2/171
发表时间：
2012-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Katherine Lee;L. Looney;D. Johnstone;J. Tobin
通讯作者：
Katherine Lee;L. Looney;D. Johnstone;J. Tobin
影响因子：
4.8
作者：
BONNOR, WB
通讯作者：
BONNOR, WB
DOI：
10.1088/2041-8205/766/2/l17
发表时间：
2013-03
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
N. Schneider;P. Andre';V. Könyves;S. Bontemps;F. Motte;C. Federrath;D. Ward-Thompson;D. Arzoumanian-D.
通讯作者：
N. Schneider;P. Andre';V. Könyves;S. Bontemps;F. Motte;C. Federrath;D. Ward-Thompson;D. Arzoumanian-D.