论文标题

Herschel Gould Belt调查观察到Cepheus Flare Cloud中的密集核心

Herschel Gould Belt Survey Observations of Dense Cores in the Cepheus Flare Clouds

论文作者

Di Francesco, James, Keown, Jared, Fallscheer, Cassandra, André, Philippe, Ladjelate, Bilal, Könyves, Vera, Men'shchikov, Alexander, Stephens-Whale, Shaun, Nguyen-Luong, Quang, Martin, Peter, Sadavoy, Sarah, Pezzuto, Stefano, Fiorellino, Eleonora, Benedettini, Milena, Schneider, Nicola, Bontemps, Sylvain, Arzoumanian, Doris, Palmeirim, Pedro, Kirk, Jason M., Ward-Thompson, Derek

论文摘要

我们介绍了Cepheus Flare Clouds L1157,L1172,L1228,L1241和L1251的Herschel Spire和PACS地图,由附近星形成的分子云的Herschel Gould Belt Survey(HGB)观察到。通过经过修改的黑体拟合尖峰和PACS数据,我们确定典型的云列密度为0.5-1.0 $ \ times $ 10 $^{21} $ cm $^{ - 2} $和14-15 K的典型云温度。使用GetSources outiources iourcorsources识别算法,我们从Spire data和piacs中提取832个密度的核心,并在160-peac中提取832个密度。从质量和尺寸图中的放置,我们认为303是候选的Prestellar核心,其中178个是“强大的” Prestellar核心。从70美元$ $ m的源独立提取,我们认为832个致密核中的25个是原始的。背景柱密度与候选Prestellar核心的分布在2-4 $ \ times $ 10 $^{21} $ cm $^{ - 2} $。由于预计将发生在“跨临界”线质量的细丝中,大约有一半的头孢菌中的候选Prestell核心可能形成。从所有五个Cepheus Clouds绘制的logNormal robust Prestellar核心质量功能(CMF)峰值为0.56 m $ _ {\ odot} $,并且宽度为$ \ sim $ 0.5 DEX,类似于Aquila的CMF。实际上,Cepheus骨料CMF的宽度与恒星系统初始质量函数(IMF)相似。 CMF宽度在不同的云中的相似性和IMF系统表明,一种常见的,可能是湍流的起源,用于播种演变成prestellar核心和恒星的波动。

We present Herschel SPIRE and PACS maps of the Cepheus Flare clouds L1157, L1172, L1228, L1241, and L1251, observed by the Herschel Gould Belt Survey (HGBS) of nearby star-forming molecular clouds. Through modified blackbody fits to the SPIRE and PACS data, we determine typical cloud column densities of 0.5-1.0 $\times$ 10$^{21}$ cm$^{-2}$ and typical cloud temperatures of 14-15 K. Using the getsources identification algorithm, we extract 832 dense cores from the SPIRE and PACS data at 160-500 $μ$m. From placement in a mass vs. size diagram, we consider 303 to be candidate prestellar cores, and 178 of these to be "robust" prestellar cores. From an independent extraction of sources at 70 $μ$m, we consider 25 of the 832 dense cores to be protostellar. The distribution of background column densities coincident with candidate prestellar cores peaks at 2-4 $\times$ 10$^{21}$ cm$^{-2}$. About half of the candidate prestellar cores in Cepheus may have formed due to the widespread fragmentation expected to occur within filaments of "transcritical" line mass. The lognormal robust prestellar core mass function (CMF) drawn from all five Cepheus clouds peaks at 0.56 M$_{\odot}$ and has a width of $\sim$0.5 dex, similar to that of Aquila's CMF. Indeed, the width of Cepheus' aggregate CMF is similar to the stellar system Initial Mass Function (IMF). The similarity of CMF widths in different clouds and the system IMF suggests a common, possibly turbulent origin for seeding the fluctuations that evolve into prestellar cores and stars.

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