AI 中文总结
研究对红移\(z = 2.236\)的强引力透镜DSFG-1进行恒星群体分析，结合JWST NIRCam成像与SMA观测，给出其恒星质量、形成率等，发现其处于星系过渡阶段，恒星年龄和尘埃衰减有空间变化，凸显多因素复杂作用。
AI 中文摘要
我们结合詹姆斯·韦布空间望远镜近红外相机成像和新的亚毫米波阵列观测，对红移\(z = 2.236\)的强引力透镜尘埃星系形成星系（DSFG）PLCK G165.7+67.0 DSFG-1进行了详细的恒星群体分析。该源被多重成像为两个透镜组件：图像1a，放大倍数适中，\(\mu \sim 5\)；图像1bc，放大倍数极高，\(\mu \sim 40\)。新的亚毫米波阵列观测在225GHz和273GHz探测到显著的尘埃连续发射，图像1a的组合通量密度为\(S_{\rm cont}=(1.19\pm0.38)\) mJy，图像1bc为\(S_{\rm cont}=(10.02\pm0.85)\) mJy，表明在亚千秒差距尺度上有活跃的恒星形成。基于综合SED建模，DSFG-1的透镜放大校正恒星质量为\(M_{\star} = (1.2 \pm 0.4) \times 10^{10} M_{\odot}\)，恒星形成率（SFR）为\((103 \pm 14) M_{\odot}\,\mathrm{yr^{-1}}\)，与之前基于\(H\alpha\)的结果相似，在该红移下比恒星形成主序列高出四倍。其在尺寸-质量平面上的位置和形态特性表明，该系统处于恒星形成晚期星系和紧凑早期星系系统之间的过渡阶段。连同其增强的恒星形成活动，这与宇宙正午期间观测到的快速演化星系一致。我们进一步研究了空间分辨恒星群体特性，发现恒星年龄和尘埃衰减存在显著的空间变化。这些结果表明恒星形成历史不均匀，并突出了尘埃几何、恒星生长和引力透镜之间的复杂相互作用，与合并情景一致。
英文摘要
We present a detailed stellar population analysis of the strongly lensed dusty star-forming galaxy (DSFG) PLCK G165.7+67.0 DSFG-1 at $z = 2.236$, combining JWST NIRCam imaging with new Submillimeter Array (SMA) observations. This source is multiply imaged into two lensed components: image 1a, with a moderate magnification factor of $μ\sim 5$, and image 1bc, with an extreme magnification factor of $μ\sim 40$. The new SMA observations detect significant dust continuum emission at 225GHz and 273GHz, with combined flux densities of $S_{\rm cont}=(1.19\pm0.38)$ mJy in image 1a and $S_{\rm cont}=(10.02\pm0.85)$ mJy in image 1bc, indicating active star formation at sub-kpc scale. Based on the integrated SED modeling, DSFG-1 exhibits a lensing amplification-corrected stellar mass of $M_{\star} = (1.2 \pm 0.4) \times 10^{10} M_{\odot}$, and a star-formation rate (SFR) of $(103 \pm 14) M_{\odot}\,\mathrm{yr^{-1}}$, similar to previous $Hα$-based results, placing it four times above the star-forming main sequence at this redshift. Its location on the size-mass plane and its morphological properties suggest that the system occupies a transitional phase between star-forming late-type galaxies and compact early-type systems. Together with its elevated star-formation activity, this is consistent with a rapidly evolving galaxy observed during Cosmic Noon. We further investigate the spatially resolved stellar population properties, and found significant spatial variations in stellar age and dust attenuation. These results point to a non-uniform star-formation history and highlight the complex interplay between dust geometry, stellar growth, and gravitational lensing, consistent with a merger scenario.
Comments16 pages, 9 figures, 3 tables, accepted by ApJ
