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外文期刊>The Astrophysical journal
>THE PROPERTIES OF THE STAR-FORMING INTERSTELLAR MEDIUM AT z = 0.8–2.2 FROM HiZELS: STAR FORMATION AND CLUMP SCALING LAWS IN GAS-RICH, TURBULENT DISKS
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THE PROPERTIES OF THE STAR-FORMING INTERSTELLAR MEDIUM AT z = 0.8–2.2 FROM HiZELS: STAR FORMATION AND CLUMP SCALING LAWS IN GAS-RICH, TURBULENT DISKS
We present adaptive optics assisted integral field spectroscopy of nine Hα-selected galaxies at z = 0.84-2.23 drawn from the HiZELS narrowband survey. Our observations map the kinematics of these star-forming galaxies on ~kpc scales. We demonstrate that within the interstellar medium of these galaxies, the velocity dispersion of the star-forming gas (σ) follows a scaling relation σ∝Σ1 SFR + constant (where ΣSFR is the star formation surface density and the constant includes the stellar surface density). Assuming the disks are marginally stable (Toomre Q = 1), this follows from the Kennicutt-Schmidt relation (ΣSFR = AΣ n gas), and we derive best-fit parameters of n = 1.34 ± 0.15 and A = 3.4+2.5 –1.6 × 10–4 M ☉?yr–1?kpc–2, consistent with the local relation, and implying cold molecular gas masses of M gas = 109-10 M ☉ and molecular gas fractions of M gas/(M gas + M ) = 0.3 ± 0.1, with a range of 10%-75%. We also identify 11 ~kpc-scale star-forming regions (clumps) within our sample and show that their sizes are comparable to the wavelength of the fastest growing mode. The luminosities and velocity dispersions of these clumps follow the same scaling relations as local H II regions, although their star formation densities are a factor ~15 ± 5?× higher than typically found locally. We discuss how the clump properties are related to the disk, and show that their high masses and luminosities are a consequence of the high disk surface density.
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机译：我们从HiZELS窄带调查中得出z = 0.84-2.23的9个Hα选择星系的自适应光学辅助积分场光谱。我们的观测结果以〜kpc尺度绘制了这些恒星形成星系的运动学图。我们证明在这些星系的星际介质中，恒星形成气体的速度色散（σ）遵循比例关系σ∝Σ1 / n SFR +常数（其中ΣSFR是恒星形成表面密度，常数包括恒星表面密度）。假设圆盘是边际稳定的（Toomre Q = 1），这是根据Kennicutt-Schmidt关系式得出的（ΣSFR=AΣn gas），我们得出的最佳拟合参数为n = 1.34±0.15和A = 3.4 + 2.5 –1.6 ×10–4 M yr？yr–1？kpc–2，与局部关系一致，表示M gas的冷分子气体质量= 109-10 M☉和M gas /（M gas + M）的分子气体分数= 0.3±0.1，范围为10％-75％。我们还确定了样本中11 kpc尺度的恒星形成区域（团块），并表明它们的大小与最快增长模式的波长相当。这些团块的光度和速度色散遵循与局部H II区域相同的比例关系，尽管它们的恒星形成密度比通常在当地发现的高约15±5？×。我们讨论了团块属性与磁盘的关系，并表明它们的高质量和亮度是磁盘表面密度高的结果。
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