We present panchromatic resolved stellar photometry for 22 million stars in the Local Group dwarf spiral Triangulum (M33), derived from Hubble Space Telescope observations with the Advanced Camera for Surveys in the optical (F475W, F814W), and the Wide Field Camera 3 in the near-ultraviolet (F275W, F336W) and near-infrared (F110W, F160W) bands. The large, contiguous survey area covers ∼14 square kpc and extends to 3.5 kpc (14′, or 1.5–2 scale lengths) from the center of M33. The PHATTER observing strategy and photometry technique closely mimics that of Panchromatic Hubble Andromeda Treasury, but with updated photometry techniques that take full advantage of all overlapping pointings (aligned to within <5–10 milliarcseconds) and improved treatment of spatially varying point-spread functions. The photometry reaches a completeness-limited depth of F475W∼28.5 in the lowest surface density regions observed in M33 and F475W∼26.5 in the most crowded regions found near the center of M33. We find the young populations trace several relatively tight arms, while the old populations show a clear, looser two-armed structure. We present extensive analysis of the data quality, including artificial star tests to quantify completeness, photometric uncertainties, and flux biases. This stellar catalog is the largest ever produced for M33, and is publicly available for download by the community.

我们展示了本地群矮螺旋三角座 (M33) 中 2200 万颗恒星的全色分辨恒星光度测量，源自哈勃太空望远镜使用光学高级相机 (F475W、F814W) 和广角相机 3 进行的观测。近紫外（F275W、F336W）和近红外（F110W、F160W）波段。大的、连续的勘测区覆盖约 14 平方千米，并从 M33 的中心延伸到 3.5 千米（14'，或 1.5-2 尺度长度）。PHATTER 观测策略和测光技术与全色哈勃仙女座金库的观测策略和测光技术非常相似，但具有更新的测光技术，可充分利用所有重叠指向（对齐在 <5-10 毫弧秒内）并改进对空间变化点扩展函数的处理。在 M33 中观察到的最低表面密度区域和 F475W~26.5 在 M33 中心附近发现的最拥挤区域中，光度测量达到了 F475W~28.5 的完整性限制深度。我们发现年轻种群追踪了几个相对紧密的手臂，而老年种群则表现出清晰、松散的双臂结构。我们对数据质量进行了广泛的分析，包括用于量化完整性、光度测量不确定性和通量偏差的人造星测试。这个恒星目录是有史以来为 M33 制作的最大的目录，可供社区公开下载。更宽松的两臂结构。我们对数据质量进行了广泛的分析，包括用于量化完整性、光度测量不确定性和通量偏差的人造星测试。这个恒星目录是有史以来为 M33 制作的最大的目录，可供社区公开下载。更宽松的两臂结构。我们对数据质量进行了广泛的分析，包括用于量化完整性、光度测量不确定性和通量偏差的人造星测试。这个恒星目录是有史以来为 M33 制作的最大的目录，可供社区公开下载。