Metal-enriched Neutral Gas Reservoir around a Strongly Lensed Low-mass Galaxy at z=4 Identified by JWST/NIRISS and VLT/MUSE

被引：11

作者：

Lin, Xiaojing ^{[1
]}

Cai, Zheng ^{[1
]}

Zou, Siwei ^{[1
]}

Li, Zihao ^{[1
]}

Chen, Zuyi ^{[2
]}

Bian, Fuyan ^{[3
]}

Sun, Fengwu ^{[2
]}

Shu, Yiping ^{[4
]}

Wu, Yunjing ^{[1
,2
]}

Li, Mingyu ^{[1
]}

Li, Jianan ^{[1
]}

Fan, Xiaohui ^{[2
]}

Prochaska, J. Xavier ^{[5
,6
]}

Schaerer, Daniel ^{[7
]}

Charlot, Stephane ^{[8
]}

Espada, Daniel ^{[9
,10
]}

Dessauges-Zavadsky, Miroslava ^{[11
]}

Egami, Eiichi ^{[2
]}

Stark, Daniel ^{[2
]}

Knudsen, Kirsten K. ^{[12
]}

Bruzual, Gustavo ^{[13
]}

Chevallard, Jacopo ^{[14
]}

机构：

[1] Tsinghua Univ, Dept Astron, Beijing 100084, Peoples R China

[2] Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA

[3] European Southern Observ, Alonso Cordova 3107, Santiago 19, Chile

[4] Chinese Acad Sci, Purple Mt Observ, 10 Yuan Hua Rd, Nanjing 210023, Jiangsu, Peoples R China

[5] Univ Calif Santa Cruz, Dept Astron & Astrophys, UCO, Lick Observ, 1156 High St, Santa Cruz, CA 95064 USA

[6] Univ Tokyo WPI, Kavli IPMU, Kashiwa 2778583, Japan

[7] Univ Geneva, Observ Geneve, Chemin Pegasi 51, CH-1290 Versoix, Switzerland

[8] Sorbonne Univ, Inst Astrophys Paris, CNRS, UMR7095, F-75014 Paris, France

[9] Univ Granada, Fac Ciencias, Dept Fis Teor & Cosmos, Campus Fuentenueva, Edificio Mecenas, E-18071 Granada, Spain

[10] Inst Carlos I Fis Teor & Computac, Fac Ciencias, E-18071 Granada, Spain

[11] Univ Geneva, Dept Astron, Chemin Pegasi 51, CH-1290 Versoix, Switzerland

[12] Chalmers Univ Technol, Dept Space Earth & Environm Chalmers Tekniska Hogs, Inst Rymd Geo Och Miljovetenskap, Gothenburg, Sweden

[13] Univ Nacl Autonoma Mexico, Inst Radio Astron & Astrophys, San Jose de la Huerta, Morelia 58089, Michoacan, Mexico

[14] Univ Oxford, Dept Phys, Denys Wilkinson Bldg, Keble Rd, Oxford OX1 3RH, England

来源：

ASTROPHYSICAL JOURNAL LETTERS | 2023年 / 944卷 / 02期

基金：

国家重点研发计划; 美国国家科学基金会;

关键词：

REST-FRAME ULTRAVIOLET; STAR-FORMING GALAXIES; UV-CONTINUUM SLOPE; LY-ALPHA EMISSION; METALLICITY EVOLUTION; ESCAPE FRACTION; LYMAN-ALPHA; LUMINOSITY FUNCTIONS; IONIZING SPECTRUM; MOSDEF SURVEY;

D O I：

10.3847/2041-8213/aca1c4

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Direct observations of low-mass, low-metallicity galaxies at z greater than or similar to 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. Combining the James Webb Space Telescope (JWST), Very Large Telescope/MUSE, and Atacama Large Millimeter/submillimeter Array, we present detailed observations of a strongly lensed, low-mass (approximate to 10(7.6) M (circle dot)) galaxy at z = 3.98 (also see Vanzella et al.). We identify strong narrow nebular emission, including C iv lambda lambda 1548, 1550, He ii lambda 1640, O iii] lambda lambda 1661, 1666, [Ne iii] lambda 3868, [O ii] lambda 3727, and the Balmer series of hydrogen from this galaxy, indicating a metal-poor H ii region (less than or similar to 0.12 Z (circle dot)) powered by massive stars. Further, we detect a metal-enriched damped Ly alpha system (DLA) associated with the galaxy with the H i column density of N (H I) approximate to 10(21.8) cm(-2). The metallicity of the associated DLA may reach the supersolar metallicity (greater than or similar to Z (circle dot)). Moreover, thanks to JWST and gravitational lensing, we present the resolved UV slope (beta) map at the spatial resolution of approximate to 100 pc at z = 4, with steep UV slopes reaching beta approximate to -2.5 around three star-forming clumps. Combining with low-redshift analogs, our observations suggest that low-mass, low-metallicity galaxies, which dominate reionization, could be surrounded by a high covering fraction of the metal-enriched, neutral-gaseous clouds. This implies that the metal enrichment of low-mass galaxies is highly efficient, and further supports that in low-mass galaxies, only a small fraction of ionizing radiation can escape through the interstellar or circumgalactic channels with low-column-density neutral gas.

引用

页数：12