LISA对银河系晕的观测：利用盖亚数据预测银河系双白矮星群体
LISA's view of the Galactic Halo: forecasts for the Galactic double white dwarf population using Gaia data
浏览论文内容
中文总结 AI 辅助
研究利用包含盖亚-香肠-土卫二的经验性银河系模型评估银河系近距离双白矮星群体规模和特征，与经典模型比较。通过模拟群体并确定引力波信号，发现纳入该成分使啁啾质量和距离分布有显著差异，引力波前景强度和高度不变。
中文摘要 AI 辅助
银河系中近距离双白矮星（DWD）群体将成为LISA分辨出的最大源群体，部分群体可通过LISA观测获得三维位置和啁啾质量测量值。白矮星是银河系恒星残骸群体的主体，LISA分辨出的近距离DWD的位置和质量由其所在的恒星群体属性决定。近期盖亚数据揭示了银河系恒星晕的三轴吸积成分：盖亚-香肠-土卫二，其中恒星比30 kpc以外恒星晕中极贫金属的恒星富含更多金属。本文利用包含盖亚-香肠-土卫二的经验性银河系模型评估近距离DWD群体的规模和特征，并与仅包含单一极贫金属晕群体的经典银河系模型进行比较。为此，我们模拟了现实的当今银河系DWD群体，并使用LEGWORK确定其在LISA中的引力波信号。我们发现，纳入盖亚-香肠-土卫二中富含金属的群体，在分辨出的DWD的啁啾质量和距离分布上产生了显著差异，但引力波前景的强度和高度保持不变。
英文摘要
The population of close double white dwarfs (DWDs) in the Milky Way will make up the largest population of sources resolved by LISA, with a subset of the population having three-dimensional position and chirp mass measurements obtained from LISA observations. Because white dwarfs are the bulk of the Milky Way's stellar remnant population, the positions and masses of close DWDs resolved by LISA are defined by the stellar population properties that host them. Recent Gaia data has unveiled a triaxial accreted component of the Galactic stellar halo: the Gaia-Sausage-Enceladus, which contains stars that are more metal-rich than the extremely metal-poor population of stars residing in the stellar halo beyond 30 kpc. In this work, we assess the size and characteristics of the population of close DWDs using an empirically motivated Galactic model which incorporates the GSE and compare to the classical Galactic model that contains only a single very metal-poor halo population. To do this, we simulate a realistic present-day Galactic DWD population and determine its gravitational wave signal in LISA using LEGWORK. We find that incorporating the metal-rich population from the GSE imprints significant differences in the chirp mass and distance distributions of resolved DWDs, but that the strength and height of the gravitational wave foreground remains unchanged.
