AI 中文总结
该研究利用JWST NIRSpec分析PEC小行星成分，发现其有富镁层状硅酸盐吸收，大小天体水蚀变程度有别，与贝努、龙宫光谱一致，光谱微弱吸收还与主带内外小天体有关，为PEC母体外太阳系形成提供证据。
AI 中文摘要
富含碳的小行星有助于了解早期太阳系，而碳质小行星家族是研究小行星内部结构和原行星盘物质的有力样本。本文通过詹姆斯·韦布空间望远镜近红外光谱仪（JWST NIRSpec）对波兰娜-尤拉莉亚小行星群（PEC）内小行星的成分进行研究。NIRSpec观测是“3微米区域主带小行星光谱分析”（SAMBA3）项目的一部分，目标包括尤拉莉亚家族同名小行星[495]尤拉莉亚以及波兰娜家族的三颗小行星。对2.7微米区域的分析表明，PEC小行星存在与富镁层状硅酸盐相关的吸收，显示过去有较高程度的水蚀变。[142]波兰娜和[495]尤拉莉亚的2.7微米波段更深，表明大小PEC小行星水蚀变程度有差异。3.0至4.0微米的微弱吸收表明[495]尤拉莉亚表面碳酸盐可能更多。此外。PEC小行星与贝努和龙宫光谱一致，其光谱中的微弱吸收还与主带内外小天体有关，为PEC母体的外太阳系形成提供了进一步证据。
英文摘要
Carbon rich [C complex] asteroids provide insight into the early Solar System, and families of C complex asteroids serve as robust samples for learning about the internal structure of planetesimals and the materials of the protoplanetary disk. This work investigates the compositions of asteroids within the Polana Eulalia Complex [PEC] through analyses of JWST NIRSpec. Obtained as part of the Spectral Analysis of Main Belt Asteroids in the 3 um Region [SAMBA3] project. NIRSpec observations were conducted for the namesake asteroid of the Eulalia family, [495] Eulalia, as well as three members from the Polana family: [2441] Hibbs, [6712] Hornstein, and [6769] Brokoff. Analyses of the 2.7 um region demonstrate that PEC asteroids exhibit absorptions associated with Mg rich phyllosilicates, in turn underscoring high, though incomplete, degrees of aqueous alteration in the past for both PEC families. Although consistent in regard to composition, [142] Polana and [495] Eulalia show deeper 2.7 um bands than the Polana family asteroids, suggesting slight differences in the degrees of aqueous alteration between large and small PEC asteroids. Minor absorptions from 3.0 to 4.0 um indicate that [495] Eulalia's surface may contain more carbonates than [142] Polana, which potentially highlights slight differences between each family's formation and evolution. Additionally, PEC asteroids also show spectral consistency with Bennu and Ryugu, reinforcing their shared origin in the PEC. Minor absorptions in PEC asteroid spectra also connect to small bodies within and beyond the Main Belt, providing further evidence of outer Solar System formation for the PEC parent bodies.
Comments75 pages, 11 sets of figures in main text and 9 figures in the appendix. Accepted in PSJ
