A Shallow Dark Matter Halo in Ultra-diffuse Galaxy AGC 242019: Are UDGs Structurally Similar to Low-surface-brightness Galaxies?

被引：14

作者：

Brook, Chris B. ^{[1
,2
]}

Di Cintio, Arianna ^{[1
,2
]}

Maccio, Andrea, V ^{[3
,4
,5
]}

Blank, Marvin ^{[3
,4
,6
]}

机构：

[1] Univ La Laguna, Avda Astrofis Fco Sanchez, E-38200 Tenerife, Spain

[2] Inst Astrofis Canarias, Calle Via Lactea S-N, E-38206 Tenerife, Spain

[3] New York Univ Abu Dhabi, POB 129188, Abu Dhabi, U Arab Emirates

[4] New York Univ Abu Dhabi, Ctr Astro Particle & Planetary Phys CAP, Abu Dhabi, U Arab Emirates

[5] Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany

[6] Christian Albrechts Univ Kiel, Inst Theoret Phys & Astrophys, Leibnizstr 15, D-24118 Kiel, Germany

来源：

ASTROPHYSICAL JOURNAL LETTERS | 2021年 / 919卷 / 01期

关键词：

RESOLUTION ROTATION CURVES; DENSITY PROFILES; DWARF GALAXIES; MASS; FEEDBACK; CORES; NIHAO; PARAMETERS; LUMINOSITY; DEPENDENCE;

D O I：

10.3847/2041-8213/ac236a

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

A central question regarding ultra-diffuse galaxies (UDGs) is whether they are in a separate category from low-surface-brightness (LSB) galaxies, or just their natural continuation toward low stellar masses. In this Letter, we show that the rotation curve of the gas rich UDG AGC 242019 is well fit by a dark matter halo with an inner slope that asymptotes to similar to-0.54, and that such a fit provides a concentration parameter that matches theoretical expectations. This finding, together with previous works in which shallow inner profiles are derived for UDGs, shows that the structural properties of these galaxies are like other observed LSBs. UDGs show slowly rising rotation curves and this favors formation scenarios in which internal processes, such as supernova-driven gas outflows, are acting to modify UDG profiles.

引用

页数：5

共 61 条

[1] Ultradiffuse galaxies: the high-spin tail of the abundant dwarf galaxy population [J].