标题： 径向速度和 MATLAS 调查矮星样本的恒星种群 显示英文标题

标题： Radial velocities and stellar populations for a sample of MATLAS survey dwarfs

摘要： 光谱观测对于确认关联、测量动力学和确定矮星系中的恒星种群至关重要。 在这里，我们展示了MATLAS调查中12个矮星系的凯克宇宙网成像仪(KCWI)光谱。 对于其中9个，我们确认了与文献中假设的宿主星系一致的退行速度。 我们提出了对MATLAS-631、1494和1938的宿主星系关联的修订。 对于MATLAS-1494，我们测量的红移将其重新分类为一个超弥散星系候选体，而不是一个较小物理尺寸的矮星系，并将其置于场中。 它似乎很古老且被动，这对那些通过潮汐效应抑制恒星形成的模型构成了挑战。 此外，我们测量了12个星系中的7个的恒星种群估计值，发现既有古老的抑制星系，也有目前正在形成恒星的星系。 与文献相比，我们发现年龄普遍较年轻，金属丰度较高。 这一结果可能有助于调和Heesters等人(2023年)报告的MATLAS调查矮星系相对于普遍恒星质量-金属丰度关系的观测偏移。 显示英文摘要

摘要： Spectroscopic observations are essential for confirming associations, measuring kinematics, and determining stellar populations in dwarf galaxies. Here, we present Keck Cosmic Web Imager (KCWI) spectra for 12 MATLAS survey dwarfs. For 9, we confirm recession velocities consistent with their literature-assumed host galaxies. We propose revisions of the host galaxy associations for MATLAS-631, 1494, and 1938. For MATLAS-1494, our measured redshift reclassifies it from an ultra-diffuse galaxy candidate to a dwarf galaxy that is of smaller physical size and places it in the field. It also appears old and passive, providing a challenge to models that invoke quenching by tidal effects. Additionally, we measure stellar population estimates for 7 of the 12 galaxies, finding a 'mixed bag' of old quenched galaxies and those that are currently forming stars. Compared to the literature we find generally younger ages and higher metallicities. This result may help reconcile the observed offset of MATLAS survey dwarf galaxies from the universal stellar mass-metallicity relationship reported by Heesters et al. (2023).