标题： 直接观测费什巴赫增强的$\it{s}$波散射的费米子 显示英文标题

标题： Direct observation of Feshbach enhanced $\it{s}$-wave scattering of fermions

摘要： 我们通过碰撞简并费米气体（DFGs）并成像散射原子，直接测量了超冷$^{40}\rm{K}$原子在磁场 Feshbach 共振处的归一化$\it{s}$波散射截面。 我们在一系列偏置磁场下提取了散射分数，并测得共振位置为$B_0 = 20.206(15)$mT，宽度为$\Delta = 1.0(5)$mT。 为了优化散射图像中原子数的信噪比，我们开发了在反冲引起的失谐校正显著的区域解释吸收图像的技术。 这些成像技术通常适用于轻碱金属实验，这些实验可以通过牺牲空间成像分辨率来最大化原子数计数的信噪比。 显示英文摘要

摘要： We directly measured the normalized $\it{s}$-wave scattering cross-section of ultracold $^{40}\rm{K}$ atoms across a magnetic-field Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. We extracted the scattered fraction for a range of bias magnetic fields, and measured the resonance location to be $B_0 = 20.206(15)$ mT with width $\Delta = 1.0(5)$ mT. To optimize the signal-to-noise ratio of atom number in scattering images, we developed techniques to interpret absorption images in a regime where recoil induced detuning corrections are significant. These imaging techniques are generally applicable to experiments with lighter alkalis that would benefit from maximizing signal-to-noise ratio on atom number counting at the expense of spatial imaging resolution.