Can Deep Research Agents Retrieve and Organize? Evaluating the Synthesis Gap with Expert Taxonomies. - Ming Zhang 030; Jiabao Zhuang; Wenqing Jing; Kexin Tan; Ziyu Kong; Jingyi Deng; Yujiong Shen; Yuhang Zhao; Ning Luo; Renzhe Zheng; Jiahui Lin; Mingqi Wu; et al. (CoRR, 2026)