论文标题
与JWST一起在早期的宇宙中找到豌豆
Finding Peas in the Early Universe with JWST
论文作者
论文摘要
JWST的早期发行观察（ERO）很好地证明了JWST在宇宙黎明中表征宇宙的希望。我们分析了三个$ z \ sim 8 $星系的ERO光谱，以确定其金属性，气体温度和电离。这些星系为通过详细的静电发射线光谱法提供了第一个机会，以理解重新电源星系的物理特性。我们表明，这些对象具有金属丰度$ 12+\ log [o/h] \约6.9-8.2 $，基于$ t_e $方法，以及最近的$ r_ {23} $ METALLICITY指示器的校准。由于光谱是JWST的一些最早的科学数据，因此我们将几个线比与鲁棒物理学预期的值进行了比较，以验证我们的测量程序。我们将丰度和排放线比与附近的绿色豌豆星系样本进行了比较 - 附近的发射线星系群的紫外线性质类似于重新电位的星系，并且通常具有较大的Lyman Continuum Cansue逃生部分。 JWST数据显示，这些高红移星系与附近的绿豌豆之间的进一步相似之处。 $ z \ sim 8 $星系横跨绿豌豆覆盖的金属范围。它们还显示了紧凑的形态，该形态在所有红移中都占主导的星系。基于与绿豌豆的相似之处，这些可能是星系的第一个休息光谱，它们正在积极推动宇宙学
The Early Release Observations (EROs) of JWST beautifully demonstrate the promise of JWST in characterizing the universe at cosmic dawn. We analyze the ERO spectra of three $z \sim 8$ galaxies to determine their metallicities, gas temperatures and ionization. These galaxies offer the first opportunity to understand the physical properties of epoch-of-reionization galaxies through detailed rest-optical emission line spectroscopy. We show that these objects have metal abundances $12+\log[O/H] \approx 6.9 - 8.2$, based on both the $T_e$ method and on a recent calibration of the $R_{23}$ metallicity indicator. Since the spectra are some of the earliest science data from JWST, we compare several line ratios with values expected from robust physics, to validate our measurement procedures. We compare the abundances and emission line ratios to a nearby sample of Green Pea galaxies -- a population of nearby emission line galaxies whose UV properties resemble epoch-of-reionization galaxies, and which often have large Lyman continuum escape fractions. The JWST data show striking further similarities between these high redshift galaxies and nearby Green Peas. The $z\sim 8$ galaxies span the metallicity range covered by Green Peas. They also show the compact morphology that is typical of emission line dominated galaxies at all redshifts. Based on these similarities with Green Peas, it is likely that these are the first rest-optical spectra of galaxies that are actively driving cosmological reionization
