Euclid：早期释放观测——IC10 矮星系的扩展恒星成分
星系天体物理
2026-01-21 v1
摘要
我们报告了对 Local Group 矮星系 IC 10 使用 Euclid Early Release Observations 中 VIS 和 NISP 波段的深层分辨恒星光度测量进行的详细分析。利用 Euclid 独特的广视场和高空间分辨率组合，我们追踪红巨星分支 (RGB) 星系至约 8 kpc 处，达到平均面积亮度水平 29 mag arcsec。我们的分析显示，IC 10 的恒星分布显然比此前所知的更为扩展。经校正前景衰减并减去银河系星星和背景星系的污染后，我们从 RGB 星计数推导出径向恒星密度轮廓。该轮廓在约 5 kpc 处显示出显著的平坦化，最佳拟合为双组分 (Sersic + 指数型) 模型，给出年龄大于 1 Gyr 的古老恒星总质量为 。外围恒星成分的起源尚不明确。它可能是被吸积的，甚至可能与 IC 10 外部 HI 气体逆转有关，亦或可能代表一种古老的原位恒星星云。我们可疑检测到两个对称的恒星超密度区位于图像边缘，这些区域大致指向 IC 10 绕 M31 轨道的方向，暗示它们可能是剥离的痕迹。作为我们的分析的一部分，我们基于 RGB 尖端推导出 IC 10 的新距离，得出 kpc，距离模为 。
引用
@article{arxiv.2601.11997,
title = {Euclid: Early Release Observations -- The extended stellar component of the IC10 dwarf galaxy},
author = {F. Annibali and A. M. N. Ferguson and P. M. Sanchez-Alarcon and P. Dimauro and L. K. Hunt and R. Pascale and M. Bellazzini and A. Lançon and P. Jablonka and J. M. Howell and K. Voggel and J. -C. Cuillandre and Abdurro'uf and G. Battaglia and L. R. Bedin and Michele Cantiello and D. Carollo and P. -A. Duc and S. S. Larsen and M. Libralato and F. R. Marleau and D. Massari and T. Saifollahi and C. Tortora and M. Urbano and M. Gatto and I. McDonald and M. Baes and J. Román and E. Dalessandro and E. Iodice and R. Ragusa and S. Pearson and S. Andreon and N. Auricchio and C. Baccigalupi and M. Baldi and A. Balestra and S. Bardelli and P. Battaglia and A. Biviano and E. Branchini and M. Brescia and S. Camera and G. Cañas-Herrera and V. Capobianco and C. Carbone and J. Carretero and S. Casas and M. Castellano and G. Castignani and S. Cavuoti and A. Cimatti and C. Colodro-Conde and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and F. Courbin and H. M. Courtois and M. Cropper and H. Degaudenzi and G. De Lucia and H. Dole and F. Dubath and C. A. J. Duncan and X. Dupac and S. Escoffier and M. Farina and R. Farinelli and S. Ferriol and F. Finelli and M. Frailis and E. Franceschi and M. Fumana and S. Galeotta and K. George and B. Gillis and C. Giocoli and J. Gracia-Carpio and A. Grazian and F. Grupp and S. V. H. Haugan and H. Hoekstra and W. Holmes and I. M. Hook and F. Hormuth and A. Hornstrup and K. Jahnke and M. Jhabvala and E. Keihänen and S. Kermiche and A. Kiessling and B. Kubik and M. Kümmel and M. Kunz and H. Kurki-Suonio and R. Laureijs and A. M. C. Le Brun and S. Ligori and P. B. Lilje and V. Lindholm and I. Lloro and G. Mainetti and D. Maino and E. Maiorano and O. Mansutti and S. Marcin and O. Marggraf and M. Martinelli and N. Martinet and F. Marulli and R. J. Massey and E. Medinaceli and S. Mei and M. Melchior and Y. Mellier and M. Meneghetti and E. Merlin and G. Meylan and A. Mora and M. Moresco and L. Moscardini and R. Nakajima and C. Neissner and S. -M. Niemi and C. Padilla and S. Paltani and F. Pasian and K. Pedersen and W. J. Percival and V. Pettorino and S. Pires and G. Polenta and M. Poncet and L. A. Popa and L. Pozzetti and F. Raison and R. Rebolo and A. Renzi and J. Rhodes and G. Riccio and E. Romelli and M. Roncarelli and R. Saglia and Z. Sakr and D. Sapone and B. Sartoris and M. Schirmer and P. Schneider and A. Secroun and G. Seidel and S. Serrano and P. Simon and C. Sirignano and G. Sirri and L. Stanco and J. Steinwagner and P. Tallada-Crespí and A. N. Taylor and I. Tereno and N. Tessore and S. Toft and R. Toledo-Moreo and F. Torradeflot and I. Tutusaus and L. Valenziano and J. Valiviita and T. Vassallo and A. Veropalumbo and Y. Wang and J. Weller and G. Zamorani and I. A. Zinchenko and E. Zucca and J. García-Bellido and J. Martín-Fleitas and V. Scottez},
journal= {arXiv preprint arXiv:2601.11997},
year = {2026}
}
备注
24 pages; 11 figures in main text; 3 Appendices. Submitted to A&A