Clustered Star Formation in the Center of NGC 253 Contributes to Driving the Ionized Nuclear Wind
Clustered Star Formation in the Center of NGC 253 Contributes to Driving the Ionized Nuclear Wind
复制标题
DOI：
10.3847/1538-4357/ac0fe8
复制
发表时间：
2021-06
期刊：
影响因子：
--
通讯作者：
E. Mills;M. Gorski;K. Emig;A. Bolatto;R. C. Levy;A. Leroy;A. Ginsburg;J. Henshaw;L. Zschaechner-L.
中科院分区：
文献类型：
--
作者：
E. Mills;M. Gorski;K. Emig;A. Bolatto;R. C. Levy;A. Leroy;A. Ginsburg;J. Henshaw;L. Zschaechner-L.
我们提出了新的3毫米观测电离气体对核星暴在附近（D <$3.5 Mpc）星系NGC 253。利用阿尔马，我们在该星系中心200 pc的空间尺度上探测到H40α和He 40 α线的辐射。复合谱线的发射主要来源于一群大约12个在形成早期嵌入的超级星星团。我们发现，从这些集群的发射的特点是电子温度范围从7000至10,000 K和测量的平均单离子化氦丰度Y += 0.25 ± 0.06，这两个是一致的测量值为H ii区域在银河系的中心。我们还报告了发现异常宽的线宽复合线发射来自七个嵌入式集群。我们认为，这些集群有助于发射的大规模热风观察到从中央星暴。最后，我们使用测得的复合线通量，以改善整体嵌入集群的特性，包括集群质量的分布和集群的星星形成的总星爆，我们估计至少有50%的贡献的表征。
We present new 3 mm observations of the ionized gas toward the nuclear starburst in the nearby (D ∼ 3.5 Mpc) galaxy NGC 253. With ALMA, we detect emission from the H40α and He40α lines in the central 200 pc of this galaxy on spatial scales of ∼4 pc. The recombination line emission primarily originates from a population of approximately a dozen embedded super star clusters in the early stages of formation. We find that emission from these clusters is characterized by electron temperatures ranging from 7000 to 10,000 K and measures an average singly ionized helium abundance 〈Y +〉 = 0.25 ± 0.06, both of which are consistent with values measured for H ii regions in the center of the Milky Way. We also report the discovery of unusually broad line width recombination line emission originating from seven of the embedded clusters. We suggest that these clusters contribute to the launching of the large-scale hot wind observed to emanate from the central starburst. Finally, we use the measured recombination line fluxes to improve the characterization of overall embedded cluster properties, including the distribution of cluster masses and the fractional contribution of the clustered star formation to the total starburst, which we estimate is at least 50%.