论文标题
低金属度星系中的热气和高质量X射线二进制排放：早期宇宙中对雾化电离和呈粉间介质加热的影响
Elevated Hot Gas and High-Mass X-ray Binary Emission in Low Metallicity Galaxies: Implications for Nebular Ionization and Intergalactic Medium Heating in the Early Universe
论文作者
论文摘要
已经提出，与恒星形成相关的高能量发射是在低金属性星爆爆的星际介质（ISM）电离的重要来源，并且是高红色（$ z> 8 $）宇宙中葡萄层间培养基（IGM）加热的重要促进者。使用Chandra观察30个星系的样本，约$ d \ $〜$〜$ 〜200-450 MPC，其高特异性恒星形成率为3--9 Gyr $^{ - 1} $，并在$ z \ odot $附近的金属率和金属性，我们提供了平均0.5--8 kev spectral spectral spectral Shape and Nimal Attrantive（S）的新测量值（我们提供新的测量值（S）。我们将样品混合的X射线光谱建模为热气和高质量X射线二元（HMXB）种群的组合，并限制其相对贡献。我们得出$ \ log l _ {\ rm 0.5-8 keV}^{\ rm hmxb} $/sfr $ = 40.19 \ pm 0.06 $和$ \ log l _ {\ rm 0.5-2 kev}^kev}^{\ rm sfr} $ = 40.19 \ pm = 40.19 \ pm = 40.19 \ pm = 40.19 \ pm = 40.19 \ pm = 40.19 \ pm = 40.19， 39.58^{+0.17} _ { - 0.28} $;与地方关系相比，显着提高。 HMXB缩放也高于$ l _ {\ rm 0.5-8 keV}^{\ rm hmxb} $ - sfr- $ z $关系，可能是由于我们的星系具有相对较低的HMXB模糊和X射线和X射线的恒星恒星恒星的星系。热气缩放关系的升高是由于金属减少而预期的衰减水平。但是，我们无法得出结论，$ l _ {\ rm 0.5-2 kev}^{\ rm as as} $ - sfr- $ z $关系仅由ISM金属内容的变化驱动。最后，我们提出了跨越X射线频段的SFR量表模型（均出现和内在），为ISM离子化和早期宇宙中IGM加热的影响提供了新的基准。
High-energy emission associated with star formation has been proposed as a significant source of interstellar medium (ISM) ionization in low-metallicity starbursts and an important contributor to the heating of the intergalactic medium (IGM) in the high-redshift ($z > 8$) Universe. Using Chandra observations of a sample of 30 galaxies at $D \approx$~200--450 Mpc that have high specific star-formation rates of 3--9 Gyr$^{-1}$ and metallicities near $Z \approx 0.3 Z_\odot$, we provide new measurements of the average 0.5--8 keV spectral shape and normalization per unit star-formation rate (SFR). We model the sample-combined X-ray spectrum as a combination of hot gas and high-mass X-ray binary (HMXB) populations and constrain their relative contributions. We derive scaling relations of $\log L_{\rm 0.5-8 keV}^{\rm HMXB}$/SFR $= 40.19 \pm 0.06$ and $\log L_{\rm 0.5-2 keV}^{\rm gas}$/SFR $= 39.58^{+0.17}_{-0.28}$; significantly elevated compared to local relations. The HMXB scaling is also somewhat higher than $L_{\rm 0.5-8 keV}^{\rm HMXB}$-SFR-$Z$ relations presented in the literature, potentially due to our galaxies having relatively low HMXB obscuration and young and X-ray luminous stellar populations. The elevation of the hot gas scaling relation is at the level expected for diminished attenuation due to a reduction of metals; however, we cannot conclude that an $L_{\rm 0.5-2 keV}^{\rm gas}$-SFR-$Z$ relation is driven solely by changes in ISM metal content. Finally, we present SFR-scaled spectral models (both emergent and intrinsic) that span the X-ray--to--IR band, providing new benchmarks for studies of the impact of ISM ionization and IGM heating in the early Universe.
