Portal de Periódicos da CAPES

Astrometry of H2O Masers in Nearby Star-Forming Regions with VERA II SVS 13 in NGC 1333

2008; Oxford University Press; Volume: 60; Issue: 1 Linguagem: Inglês

10.1093/pasj/60.1.37

2053-051X

Tomoya Hirota, Takeshi Bushimata, Yoon Kyung Choi, Mareki Honma, Hiroshi Imai, Kenzaburo Iwadate, Takaaki Jike, Osamu Kameya, Ryuichi Kamohara, Yukitoshi Kan‐ya, Noriyuki Kawaguchi, Masachika Kijima, Hideyuki Kobayashi, Seisuke Kuji, Tomoharu Kurayama, Seiji Manabe, Takeshi Miyaji, Takumi Nagayama, Akiharu Nakagawa, Chung Sik Oh, Toshihiro Omodaka, Tomoaki Oyama, Satoshi Sakai, Tetsuo Sasao, Katsuhisa Sato, Katsunori M. Shibata, Yoshiaki Tamura, Kazuyoshi Yamashita,

Galaxies: Formation, Evolution, Phenomena

We report on the results of multi-epoch VLBI observations with VERA (VLBI Exploration of Radio Astrometry) of the 22 GHz H2O masers associated with the young stellar object SVS 13 in the NGC 1333 region. We have carried out phase-referencing VLBI astrometry and measured an annual parallax of the maser features in SVS 13 of 4.25+/-0.32 mas, corresponding to the distance of 235+/-18 pc from the Sun. Our result is consistent with a photometric distance of 220 pc previously reported. Even though the maser features were detectable only for 6 months, the present results provide the distance to NGC 1333 with much higher accuracy than photometric methods. The absolute positions and proper motions have been derived, revealing that the H2O masers with the LSR (local standard of rest) velocities of 7-8 km s-1 are most likely associated with VLA4A, which is a radio counterpart of SVS 13. The origin of the observed proper motions of the maser features are currently difficult to attribute to either the jet or the rotating circumstellar disk associated with VLA4A, which should be investigated through future high-resolution astrometric observations of VLA4A and other radio sources in NGC 1333.