VERA observation of the W 49N H2O maser outburst in 2003 October

被引:12
|
作者
Honma, M [1 ]
Choi, YK
Bushimata, T
Fujii, T
Hirota, T
Horiai, K
Imai, H
Inomata, N
Ishitsuka, J
Iwadate, K
Jike, T
Kameya, O
Kamohara, R
Kan-Ya, Y
Kawaguchi, N
Kobayashi, H
Kuji, S
Kurayama, T
Manabe, S
Myaji, T
Nakagawa, A
Nakashima, K
Nagayoshi, R
Omodaka, T
Oyama, T
Rioja, M
Sakai, S
Sakakibara, SI
Sato, K
Sasao, T
Shibata, KM
Shimizu, R
Sora, K
Suda, H
Tamura, Y
Yamashita, K
机构
[1] NAOJ, VERA Project Off, Mitaka, Tokyo 1818588, Japan
[2] NAOJ, Earth Rotat Div, Mizusawa, Iwate 0230861, Japan
[3] Grad Univ Adv Studies, Mitaka, Tokyo 1818588, Japan
[4] Univ Tokyo, Dept Astron, Bunkyo Ku, Tokyo 1138654, Japan
[5] NAOJ, Radio Astron Div, Mitaka, Tokyo 1818588, Japan
[6] Kagoshima Univ, Fac Sci, Kagoshima 8900065, Japan
[7] NAOJ, Mizusawa Astro Geodynam Observ, Mizusawa, Iwate 0230861, Japan
[8] Ajou Univ, Suwon 442749, South Korea
关键词
ISM : H-II regions; ISM : individual (W 49N); masers (H2O); star formation; VERA;
D O I
10.1093/pasj/56.3.L15
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We report on a strong outburst of the W 49N H2O maser observed with VERA. Single-dish monitoring with VERA 20 m telescopes detected a strong outburst of the maser feature at V-LSR = -30.7 kms(-1) in 2003 October. The outburst had a duration of similar to 100 days and a peak intensity of 7.9 x 10(4) Jy, being one of the strongest outbursts in W 49N observed so far. VLBI observations with the VERA array were also carried out near to the maximum phase of the outburst, and the outburst spot was identified in the VLBI map. While the map was in good agreement with previous studies, showing three major concentrations of maser spots, we found a newly formed arc-like structure in the central maser concentration, which may be a shock front powered by a forming star or a star cluster. The outburst spot was found to be located on the arc-like structure, indicating a possible connection of the present outburst to a shock phenomenon.
引用
收藏
页码:L15 / L18
页数:4
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