Time Monitoring of Radio Jets and Magnetospheres in the Nearby Young Stellar Cluster R Coronae Australis
- Autor(en)
- Hauyu Baobab Liu, Roberto Galván-Madrid, Jan Forbrich, Luis F. Rodríguez, Michihiro Takami, Gráinne Costigan, Carlo Felice Manara, Chi-Hung Yan, Jennifer L. Karr, Mei-Yin Chou, Paul T. P. Ho, Qizhou Zhang
- Abstrakt
We report Karl G. Jansky Very Large Array 8-10 GHz (λ = 3.0-3.7 cm) monitoring observations toward the young stellar object (YSO) cluster R Coronae Australis (R CrA), taken from 2012 March 15 to 2012 September 12. These observations were planned to measure the radio flux variabilities in timescales from 0.5 hr to several days, to tens of days, and up to 200 days. We found that among the YSOs detectable in individual epochs, in general, the most reddened objects in the Spitzer observations show the highest mean 3.5 cm Stokes I emission, and the lowest fractional variabilities on <200 day timescales. The brightest radio flux emitters in our observations are the two reddest sources IRS7W and IRS7E. In addition, by comparing our observations with observations taken from 1996 to 1998 and 2005, we found that the radio fluxes of these two sources have increased by a factor of 1.5. The mean 3.5 cm fluxes of the three Class I/II sources, IRSI, IRS2, and IRS6, appear to be correlated with their accretion rates derived by a previous near-infrared line survey. The weakly accreting Class I/II YSOs, or those in later evolutionary stages, present radio flux variability on <0.5 hr timescales. Some YSOs were detected only during occasional flaring events. The source R CrA went below our detection limit during a few fading events.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- Academia Sinica - Taiwan, European Southern Observatory (Germany), Dublin Institute for Advanced Studies, National Taiwan Normal University, Harvard-Smithsonian Center for Astrophysics, Universidad Nacional Autonoma de Mexico
- Journal
- The Astrophysical Journal
- Band
- 780
- Anzahl der Seiten
- 14
- ISSN
- 0004-637X
- DOI
- https://doi.org/10.1088/0004-637X/780/2/155
- Publikationsdatum
- 01-2014
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Schlagwörter
- ASJC Scopus Sachgebiete
- Astronomy and Astrophysics, Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/76698cb2-5319-4539-aea1-0b7904b4e9f7