Collaborative Research: Exploring the Dark Side of NGC 5128

合作研究：探索 NGC 5128 的黑暗面

• 批准号: 1813708
• 负责人: David Sand
• 金额: $ 25.55万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1813708&HistoricalAwards=false
• 关键词: Collaborative; Research; Exploring; Dark; Side

The investigators will study the outskirts of the nearest giant elliptical galaxy, named Centaurus A, to learn how the galaxy built up its stellar and dark matter mass over cosmic time. The investigators have measured the positions of nearly all the luminous star clusters associated with Centaurus A, and will precisely measure their velocities using large ground-based telescopes. Using observations of the collection of star clusters, and their motions around Centaurus A, the investigators will measure the dark matter density profile of the galaxy, and search for remnants of smaller galaxies that have merged with Centaurus A. The important goal of their observations is identifying large star clusters which are the remnants left over from smaller galaxies after they have been devoured by the larger Centaurus A. By studying the motions of these star clusters in detail, along with the smaller galaxies it has destroyed, they will have a complete inventory of the 'dark side' of Centaurus A. Their results will be applied to studies of all galaxy populations. The investigators will present the science results from this program to visitors at the National Science Foundation's Kitt Peak National Observatory, by implementing a new docent training program at the visitor center. The investigators will travel to Bryce Canyon National Park and present their results, through summer internships, which ultimately teach 16,000 visitors about the night sky.The currently favored cold dark matter model makes clear predictions for the sub-halo mass function and dark matter density profile of galaxy-sized halos, but quantitatively verifying these predictions is challenging. Centaurus A's dark matter density profile will be measured, using the kinematics derived from a nearly complete sample of star clusters, and the results compared to recent simulations that suggest galaxies with recent mergers and active galactic nuclei should have shallow dark matter profiles. By combining the star cluster kinematics with an already existing red giant branch star map, the visible, accreted substructures will be identified and weighed. Finally, a complete sample of ultra-compact dwarfs will be analyzed, including a search identifying them as the central compact remnants of stripped dwarf galaxies. Accounting for this population of sub-halos is a novel aspect of this program, and one that has largely been neglected when testing galaxy formation models. These efforts will test major predictions of the cold dark matter model at sub-galactic scales in our nearest elliptical galaxy neighbor.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

研究人员将研究最近的巨型椭圆星系（名为半人马座 A）的外围，以了解该星系在宇宙时间内如何形成其恒星和暗物质质量。 研究人员已经测量了几乎所有与半人马座 A 相关的发光星团的位置，并将使用大型地面望远镜精确测量它们的速度。 通过对星团集合及其围绕半人马座 A 运动的观测，研究人员将测量星系的暗物质密度分布，并寻找与半人马座 A 合并的较小星系的残余物。他们观测的重要目标是识别大型星团，这些星团是较小星系被较大的半人马座 A 吞噬后留下的残余物。通过详细研究这些星团以及较小星系的运动当它被摧毁时，他们将拥有半人马座 A 的“黑暗面”的完整清单。他们的结果将应用于所有星系群体的研究。 研究人员将通过在游客中心实施新的讲解员培训计划，向美国国家科学基金会基特峰国家天文台的游客展示该计划的科学成果。 研究人员将前往布莱斯峡谷国家公园，通过暑期实习展示他们的结果，最终向 16,000 名游客传授有关夜空的知识。目前流行的冷暗物质模型对亚晕质量函数和暗物质密度分布做出了明确的预测星系大小的光晕，但定量验证这些预测具有挑战性。 半人马座 A 的暗物质密度剖面将使用从几乎完整的星团样本中得出的运动学进行测量，并将结果与​​最近的模拟进行比较，这些模拟表明最近合并的星系和活跃的星系核应该具有浅的暗物质剖面。 通过将星团运动学与现有的红巨星分支星图相结合，可见的、吸积的子结构将被识别和称重。 最后，将对超致密矮星的完整样本进行分析，包括将它们识别为剥离矮星系的中心致密残余物的搜索。 考虑到这些子晕的数量是该计划的一个新颖方面，并且在测试星系形成模型时很大程度上被忽视了。 这些努力将在我们最近的椭圆星系邻居的亚星系尺度上测试冷暗物质模型的主要预测。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

The Faint End of the Centaurus A Satellite Luminosity Function

• DOI: 10.3847/1538-4357/aafbe7
• 发表时间: 2018-09
• 期刊: The Astrophysical Journal
• 作者: D. Crnojevi'c;D. Sand;P. Bennet;S. Pasetto;K. Spekkens;N. Caldwell;P. Guhathakurta;B. McLeod;A. Seth;J. Simon;J. Strader;E. T. U. O. Tampa;Tâmpa;Fl;USA.;D. PhysicsAstronomy;Texas Tech University;Lubbock;Tx;D. O. Astronomy;S. Observatory;U. Arizona;Tucson;Az;Observatories of the Carnegie Institution for Science-Observatories-of-the-Carnegie-Institution-for-102557742;Pasadena;Ca;Department of Materials Science;Royal Military College of Canada;Kingston;Ontario;Canada;H. C. F. Astrophysics;Cambridge;Ma;D. O. AstronomyAstrophysics;University of California at Santa Cruz;D. Physics;Astronomy;U. Utah;Salt lake City;Ut;M. University;E. Lansing.;Mi;U. Pacific;Stockton

Mapping Dark Matter with Extragalactic Stellar Streams: The Case of Centaurus A

用河外恒星流绘制暗物质图：半人马座 A 的案例

• DOI: 10.3847/1538-4357/ac9bfb
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Pearson, Sarah;Price-Whelan, Adrian M.;Hogg, David W.;Seth, Anil C.;Sand, David J.;Hunt, Jason A.;Crnojević, Denija
• 通讯作者: Crnojević, Denija

Resolved Dwarf Galaxy Searches within ∼5 Mpc with the Vera Rubin Observatory and Subaru Hyper Suprime-Cam*

使用 Vera Rubin 天文台和 Subaru Hyper Suprime-Cam* 解决了 â⁄5 Mpc 内的矮星系搜索问题*

• DOI: 10.3847/1538-4357/ac0db8
• 发表时间: 2021
• 期刊: The Astrophysical Journal
• 作者: Mutlu-Pakdil, Burçin;Sand, David J.;Crnojević, Denija;Drlica-Wagner, Alex;Caldwell, Nelson;Guhathakurta, Puragra;Seth, Anil C.;Simon, Joshua D.;Strader, Jay;Toloba, Elisa
• 通讯作者: Toloba, Elisa