arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2208.08473astro-ph.GA
收藏

用JWST和ALMA在$z=3.06$鉴别尘埃多臂螺旋星系

The Identification of a Dusty Multiarm Spiral Galaxy at $z=3.06$ with JWST and ALMA

Yunjing Wu, Zheng Cai, Fengwu Sun, Fuyan Bian, Xiaojing Lin, Zihao Li, Mingyu Li, Franz E. Bauer, Eiichi Egami, Xiaohui Fan, Jorge González-López, Jianan Li, Fe… 展开作者

Yunjing Wu, Zheng Cai, Fengwu Sun, Fuyan Bian, Xiaojing Lin, Zihao Li, Mingyu Li, Franz E. Bauer, Eiichi Egami, Xiaohui Fan, Jorge González-López, Jianan Li, Feige Wang, Jinyi Yang, Shiwu Zhang, Siwei Zou

摘要:

螺旋臂在恒星形成和星系演化中起着至关重要的作用。本文报道了利用詹姆斯·韦伯空间望远镜(JWST)的近红外光谱成像和棱镜光谱对$z=3.059$的一个尘埃多臂螺旋星系A2744-DSG-$z3$的识别。A2744-DSG-$z3$是由ALMA发现的一个引力透镜亚毫米星系。这是迄今为止看到的最遥远的恒星螺旋结构,与宇宙学模拟相一致,该模拟表明PDMATHAMO是螺旋出现的时代。由于JWST的引力透镜效应和出色的空间分辨率,螺旋臂的空间分辨率为$\approx290$ \,pc。根据SED拟合,该螺旋星系的去透镜恒星形成率为$85\pm30 \ M_{\odot}$ yr $^{-1}$,恒星质量为$\approx10^{10.6}\ M_{\odot}$,表明A2744-DSG- $z3$是一个主序星星系。拟合旋臂后,得到恒星有效半径($R_{e, \rm{star}}$)为$5.0\pm1.5$ kpc。结合ALMA测量结果,我们发现尘埃与恒星的有效半径比为$\approx0.4$,与大质量SFG在$z\sim2$处的半径比相似,表明A2744-DSG- $z3$中存在致密的尘埃核。此外,这个星系似乎生活在一个星系群环境中:包括A2744-DSG- $z3$在内,至少有三个位于$z=3.05 - 3.06$的星系被JWST/NIRISS和ALMA光谱证实,它们居住在$\approx 70$ kpc的透镜校正投影尺度内。这与不对称的亮度轮廓一起,进一步表明螺旋臂可能是由$z\gtrsim3$的小合并事件触发的。

英文摘要:

Spiral arms serve crucial purposes in star formation and galaxy evolution. In this paper, we report the identification of A2744-DSG-$z3$, a dusty, multiarm spiral galaxy at $z=3.059$ using the James Webb Space Telescope (JWST) NIRISS imaging and grism spectroscopy. A2744-DSG-$z3$ was discovered as a gravitationally lensed sub-millimeter galaxy with ALMA. This is the most distant stellar spiral structure seen thus far, consistent with cosmological simulations which suggest $z\approx3$ as the epoch when spirals emerge. Thanks to the gravitational lensing and excellent spatial resolution of JWST, the spiral arms are resolved with a spatial resolution of $\approx290$\,pc. Based on SED fitting, the spiral galaxy has a de-lensed star formation rate of $85\pm30 \ M_{\odot}$ yr$^{-1}$, and a stellar mass of $\approx10^{10.6}\ M_{\odot}$, indicating that A2744-DSG-$z3$ is a main-sequence galaxy. After fitting the spiral arms, we find a stellar effective radius ($R_{e, \rm{star}}$) of $5.0\pm1.5$ kpc. Combing with ALMA measurements, we find that the effective radii ratio between dust and stars is $\approx0.4$, similar to {those} of massive SFGs at $z\sim2$, indicating a compact dusty core in A2744-DSG-$z3$. Moreover, this galaxy appears to be living in a group environment: including A2744-DSG-$z3$, at least three galaxies at $z=3.05 - 3.06$ {are} spectroscopically confirmed by JWST/NIRISS and ALMA, residing within a lensing-corrected projected scale of $\approx 70$ kpc. This, along with the asymmetric brightness profile, further suggests that the spiral arms may be triggered by minor merger events at $z\gtrsim3$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑