论文标题
通过比较Z $ \ sim $ 1的紫外线和h $α$ in的星星形成爆发的空间分析与uvcandels进行比较
A spatially resolved analysis of star-formation burstiness by comparing UV and H$α$ in galaxies at z$\sim$1 with UVCANDELS
论文作者
论文摘要
宇宙组装近红外深层遗传遗产调查场（UVCANDELS）计划的紫外线成像为四个烛台提供了HST/UVIS F275W成像。我们将这种UV成像与现有的HST/近IIR GRISM光谱相结合，从3D-HST $+$ aghast直接比较了979个星系的样本，以0.7 <z <z <z <z <1.5 $ <1.5 $的范围为$ 10^^$ 10^{8-11.5} $ $的979个星系的样本，以比较979个星系的样本。使用堆叠分析，我们在REST-UV和H $α$的均质图之间进行了分解的比较，以计算平均UV-H $α$α$亮度比（恒星形成中爆发的指标）作为半半径的函数。我们发现，$ \ sim $ 10 $^{9.5} $ m $ _ \ odot $的星系质量低于$ \ sim $ \ sim $^{9.5} $ _ \ odot $，在所有半径上，UV-to-t-to-h $α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$α$比率高于恒星形成所预期的平衡值，这表明爆发型星形构成产生了重要的贡献。即使对于具有恒星质量$ \ gtrsim的星系$ 10 $^{9.5} $ m $ $ _ \ odot $，UV-to-to-t-to-h $α$比率在其郊区（$ r/r_ {eff}> 1.5 $）的郊区（$ r_ r_ {eff}> 1.5 $）都可能超出了繁重的范围，甚至很可能是庞大的，甚至很可能出现了众多的天气。内核。 Furthermore, we present the UV-to-H$α$ ratio as a function of galaxy surface brightness, a proxy for stellar mass surface density, and find that regions below $\sim$10$^{7.5}$ M$_\odot$ kpc$^{-2}$ are consistent with bursty star-formation, regardless of their galaxy stellar mass, potentially suggesting that local star-formation is在最小的尺度上独立于全局星系特性。最后，无论半径或表面亮度如何，我们都发现$ z> 1.1 $的星系具有爆发的恒星形成。
The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) program provides HST/UVIS F275W imaging for four CANDELS fields. We combine this UV imaging with existing HST/near-IR grism spectroscopy from 3D-HST$+$AGHAST to directly compare the resolved rest-frame UV and H$α$ emission for a sample of 979 galaxies at $0.7<z<1.5$ spanning a range in stellar mass of $10^{8-11.5}$ M$_\odot$. Using a stacking analysis, we perform a resolved comparison between homogenized maps of rest-UV and H$α$ to compute the average UV-to-H$α$ luminosity ratio (an indicator of burstiness in star-formation) as a function of galactocentric radius. We find that galaxies below stellar mass of $\sim$10$^{9.5}$ M$_\odot$, at all radii, have a UV-to-H$α$ ratio higher than the equilibrium value expected from constant star-formation, indicating a significant contribution from bursty star-formation. Even for galaxies with stellar mass $\gtrsim$10$^{9.5}$ M$_\odot$, the UV-to-H$α$ ratio is elevated towards in their outskirts ($R/R_{eff}>1.5$), suggesting that bursty star-formation is likely prevalent in the outskirts of even the most massive galaxies but is likely over-shadowed by their brighter cores. Furthermore, we present the UV-to-H$α$ ratio as a function of galaxy surface brightness, a proxy for stellar mass surface density, and find that regions below $\sim$10$^{7.5}$ M$_\odot$ kpc$^{-2}$ are consistent with bursty star-formation, regardless of their galaxy stellar mass, potentially suggesting that local star-formation is independent of global galaxy properties at the smallest scales. Lastly, we find galaxies at $z>1.1$ to have bursty star-formation regardless of radius or surface brightness.
