AI 中文总结
该研究利用JWST中波段成像数据，首次自洽测量1.25<z<6.6的Hα光度函数，推导尘埃校正后的恒星形成率函数与宇宙恒星形成率密度演化，发现z~2处峰值、z=6处下降且归一化程度更高的结果。
AI 中文摘要
我们首次实现了从宇宙正午到再电离纪元的宽红移范围内Hα光度函数的自洽测量。本研究采用基于詹姆斯·韦布空间望远镜（JWST）NIRCam中波段成像的新方法，结合CANUCS、JWST in Technicolor和JUMPS巡天的数据，这些数据提供了深度均匀的成像（29.5-30 AB星等，3σ），并拥有广泛的NIRCam中波段覆盖，若加入辅助的哈勃空间望远镜（HST）ACS和WFC3/UVIS数据，总滤镜可达29个（其中JWST滤镜最多20个）。出色的光谱能量分布（SED）采样实现了精确可靠的测光红移估计（异常值比例为1.7%，本样本的σ_NMAD=0.039），以及经光谱后续观测验证的准确连续谱扣除和线流量测量（无系统偏差，弥散为0.23 dex）。我们通过追踪11个中波段滤镜中的Hα发射线，测量了1.25 < z < 6.6范围内的Hα光度函数（LF）。深度、红移覆盖范围与统计效力的结合是独特的，为光度跨越近三个数量级的LF形状提供了强约束。我们密集的SED采样使我们能够可靠地校正尘埃消光，推导尘埃校正后的恒星形成率函数，以及整个红移范围内宇宙恒星形成率密度的演化。我们在z~2处恢复了峰值，向z=6处呈下降趋势，但归一化程度更高，与近期红外（IR）测量结果比紫外（UV）测量结果更一致，且同时超越了两者。这种潜在的张力将在未来利用具有中红外（MIR）覆盖的更大规模巡天的工作中解决，以更好地约束光度函数的亮端和尘埃的影响。
英文摘要
We present the first self-consistent measurement of the Hα luminosity function over a wide redshift range, covering cosmic noon into the epoch of reionization. Our analysis utilizes a novel method based on James Webb Space Telescope (JWST) NIRCam medium-band imaging. We combine data from the CANUCS, JWST in Technicolor, and JUMPS surveys which offer deep, uniform imaging (29.5-30 AB, 3σ) with extensive NIRCam medium-band coverage, reaching up to 29 total filters (up to 20 JWST) when including ancillary Hubble Space Telescope (HST) ACS and WFC3/UVIS data. The superb spectral energy distribution (SED) sampling enables precise, reliable photometric redshift estimation (outlier fraction 1.7\%, σ N_MAD = 0.039 for this sample) as well as accurate continuum subtraction and line flux measurement verified by spectroscopic follow-up (no systematic offset, 0.23 dex scatter). We measure the Hα luminosity function (LF) from 1.25 < z < 6.6 by tracing the Hα emission line in 11 medium-band filters. The combination of depth, redshift coverage, and statistical power is unique, providing strong constraints on the shape of the LF over almost three orders of magnitude in luminosity. Our dense SED sampling enables us to reliably correct for dust attenuation and derive dust-corrected star formation rate functions as well as the evolution of the cosmic star formation rate density over the full redshift range. We recover the peak at z ~ 2 and a decrease toward z = 6, though with a higher normalization more in line with recent IR measurements than UV, though eclipsing both. This potential tension will be addressed in future work utilizing larger surveys with MIR coverage to better constrain the bright end of the luminosity function and the effects of dust.
Comments15 pages, 9 figures, 3 tables
