期刊
ASTRONOMY & ASTROPHYSICS
卷 651, 期 -, 页码 -出版社
EDP SCIENCES S A
DOI: 10.1051/0004-6361/202141002
关键词
stars; AGB and post-AGB; circumstellar matter; binaries; close; binaries; symbiotic; stars; individual; R Aqr
资金
- Spanish MICINN [AYA2016-78994-P, AYA2016-75066-C2-1-P, PID2019-105203GB-C2, PID2019-106110GB-I00, PID2019-107115GB-C21]
- National Science Centre, Poland [OPUS 2017/27/B/ST9/01940]
- Ramon y Cajal programme of Spanish MICIU [RyC-2014-16277]
- European Research Council (ERC) [610256: NANOCOSMOS]
- National Research Foundation of Korea (NRF) - Korea government (MIST) [2021R1A2C1008928]
- National Research Foundation of Korea [2021R1A2C1008928] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
This study investigates the structure, dynamics, and chemistry of the molecule-rich nebula around the stellar symbiotic system R Aqr, which is significantly influenced by the presence of a white dwarf companion. Through high-quality ALMA maps and sophisticated calculations, the research reveals the detailed structure and dynamics of the nebula, shedding light on the effects of the WD on the circumstellar shells.
Aims. We investigate the structure, dynamics, and chemistry of the molecule-rich nebula around the stellar symbiotic system R Aqr, which is significantly affected by the presence of a white dwarf (WD) companion. We study the effects of the strong dynamical interaction between the AGB wind and the WD and of photodissociation by the WD UV radiation on the circumstellar shells. Methods. We obtained high-quality ALMA maps of the (CO)-C-12 J = 2-1, J = 3-2, and J = 6-5 lines and of (CO)-C-13 J = 3-2. The maps were analyzed by means of a heuristic 3D model that is able to reproduce the observations. In order to interpret this description of the molecule-rich nebula, we performed sophisticated calculations of hydrodynamical interaction and photoinduced chemistry. Results. We find that the CO-emitting gas is distributed within a relatively small region less than or similar to 1.'' 5. Its structure consists of a central dense component plus strongly disrupted outer regions, which seem to be parts of spiral arms that are highly focused on the orbital plane. The structure and dynamics of these spiral arms are compatible with our hydrodynamical calculations. We argue that the observed nebula is the result of the dynamical interaction between the wind and the gravitational attraction of the WD. We also find that UV emission from the hot companion efficiently photodissociates molecules except in the densest and best-shielded regions, that is, in the close surroundings of the AGB star and some shreds of the spiral arms from which the detected lines come. We can offer a faithful description of the distribution of nebular gas in this prototypical source, which will be a useful template for studying material around other tight binary systems.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据