论文标题
辣椒ver：在宇宙场的空前深度和节奏处的无线电变异性
CHILES VERDES: Radio variability at an unprecedented depth and cadence in the COSMOS field
论文作者
论文摘要
尽管有一个良好的确定性的是某些时期的无线电来源是时间变化，但该无线电可变性的特性及其与宿主星系性能的联系仍有待探索 - 尤其是对于微弱的来源。在这里，我们介绍了来自辣椒变量的无线电变量源的分析和爆炸性的无线电动力学进化调查（智利佛教）--- 1.4 GHz Cosmos \ ion \ ion {H} {1} {1}大型大型外层面调查（辣椒）的合作伙伴项目。智利verdes提供了调查深度，持续时间和节奏的前所未有的组合，960小时为1--2 GHz Continuum vla数据在2013年至2019年之间在0.44 ver $^2 $中获得了209个时期，$^2 $，$^2 $^2 $ the良好的外层面深地上的深层田野，cosmos。我们确定了18个中等变异性来源（显示$ 10-30 \％$通量密度变化）和40个较低的可变性来源（2-10 $ \％$ plux密度变化）。它们主要是主动银河核（AGN），其无线电照明范围为$ 10^{22} -10^{27} $ W Hz $^{ - 1} $，基于与Cosmos多波长目录的交叉匹配。中等变异性来源跨越红移$ z = 0.22-1.56 $，主要是平坦的无线电光谱（$α> -0.5 $），并且在几天到几年之间的时间表不等。低变量源具有相似的属性，但通常比中等变差源具有更高的无线电亮度，扩展到$ z = 2.8 $，并且无线电光谱（$α<-0.5 $）。在我们的分析中，没有星形的星系显示出统计学上的显着差异。观察到的可变性可能起源于短（$ \ sim $周）时标上的闪烁以及多普勒增强的固有AGN变异性的长（月 - 年度）时间表。
Although it is well-established that some extragalactic radio sources are time-variable, the properties of this radio variability, and its connection with host galaxy properties, remain to be explored---particularly for faint sources. Here we present an analysis of radio variable sources from the CHILES Variable and Explosive Radio Dynamic Evolution Survey (CHILES VERDES)---a partner project of the 1.4 GHz COSMOS \ion{H}{1} Large Extragalactic Survey (CHILES). CHILES VERDES provides an unprecedented combination of survey depth, duration, and cadence, with 960 hrs of 1--2 GHz continuum VLA data obtained over 209 epochs between 2013 and 2019 in a 0.44 deg$^2$ section of the well-studied extragalactic deep field, COSMOS. We identified 18 moderate-variability sources (showing $10-30\%$ flux density variation) and 40 lower variability sources (2-10$\%$ flux density variation). They are mainly active galactic nuclei (AGN) with radio luminosities in the range of $10^{22}-10^{27}$ W Hz$^{-1}$ based on cross-matching with COSMOS multi-wavelength catalogs. The moderate-variability sources span redshifts $z=0.22-1.56$, have mostly flat radio spectra ($α>-0.5$), and vary on timescales ranging from days to years. Lower-variability sources have similar properties, but have generally higher radio luminosities than the moderate-variability sources, extend to $z = 2.8$, and have steeper radio spectra ($α<-0.5$). No star-forming galaxy showed statistically significant variability in our analysis. The observed variability likely originates from scintillation on short ($\sim$week) timescales, and Doppler-boosted intrinsic AGN variability on long (month--year) timescales.
