Study of 3-D structure of Orion-Monoceros Molecular Cloud complex with high-precision VLBI

利用高精度 VLBI 研究 Orion-Monoceros 分子云复合体的 3-D 结构

• 批准号: 16540224
• 负责人: HIROTA Tomoya
• 金额: $ 2.05万
• 依托单位: Nation Astronomical Observatory of Japan
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540224/
• 关键词: Radio Astronomy; VLBI; Star Formation; Molecular Cloud; Protostar; Water Maser; Astrometry; Galactic Astronomy; 原始; 相対VLBI

VERA is a newly constructed VLBI array promoted by National Astronomical Observatory of Japan in collaboration with Kagoshima University. VERA aims to measure the annual parallaxes of maser sources associated with star-forming regions and Mira valuables in the Galaxy with an accuracy of 10 micro arcseconds. In this project, we plan to measure the distance and 3-dimensional structure of Orion-Monoceros Molecular Cloud complex, which is the nearest high-mass star-forming region, with VERA.At first, we performed a survey of 20 H2O maser sources in Orion-Moniceros Molecular Cloud complex and confirmed that 4 sources were detectable with VERA. Based on this result, we started multi-epoch VLBI monitoring observations of these 4 H2O maser sources ; Orion KL, HH1, OMC-2, and Mon R2. Using the VERA dual-beam receiving system, we performed phase-referencing VLBI and successfully measured absolute proper motion of H2O maser features with respect to the nearby extragalactic radio sources. We detected the annual parallax of Orion KL, 2.3 milli arcseconds, corresponding to the distance of 430 pc from the Sun. This value is consistent with that reported by Genzel et al. (1980), 480 +/- 80 pc, which is determined from the proper motion and radial velocity of the maser features. For other sources, we have not yet obtained annual parallax because the life time of H2O maser features were typically as short as 4-6 months. Therefore, we continue monitoring observations of these sources with VERA.

VERA是日本国立天文台与鹿儿岛大学合作推出的一个新建成的VLBI阵列。VERA的目标是测量与银河系中的恒星形成区和Mira贵重物有关的脉泽源的年度弛豫，精度为10微弧秒。在本项目中，我们计划利用VERA测量距离最近的大质量恒星形成区--猎户座-麒麟座分子云复合体的距离和三维结构。首先，我们对猎户座-麒麟座分子云复合体中的20个H2O脉泽源进行了测量，确认其中4个源是VERA可探测到的。在此基础上，我们开始了对Orion KL、HH 1、OMC-2和Mon R2这4个H2O脉泽源的多历元VLBI监测观测。利用VERA双光束接收系统，我们进行了相位参考VLBI，并成功地测量了H_2O脉泽特征相对于附近河外射电源的绝对自行。我们探测到猎户座KL的年视差为2.3毫角秒，相当于距离太阳430 pc。这个值与Genzel等人（1980）报道的480 ± 80秒差距是一致的，后者是由脉泽特征的自行和径向速度确定的。对于其他来源，我们还没有获得年视差，因为H2O脉泽特征的寿命通常短至4-6个月。因此，我们继续监测VERA对这些来源的观察。

项目成果

First mm-VLBI Observations between the TRAO 14-m and the NRO 45-m Telescopes: Observations of 86 GHz SiO Masers in VY Canis Majoris

• DOI: 10.1093/pasj/56.3.475
• 发表时间: 2004-06
• 期刊: Publications of the Astronomical Society of Japan
• 影响因子: 2.3
• 作者: K. Shibata;H. Chung;S. Kameno;D. Roh;T. Umemoto;Kwang-Dong Kim;K. Asada;Seog-Tae Han;N. Mochizuki;Se-Hyung Cho;S. Sawada-Satoh;Hyun-Goo Kim;T. Bushimata;Y. Minh;T. Miyaji;N. Kuno;H. Mikoshiba;K. Sunada;M. Inoue;H. Kobayashi

The kinematics of water masers in the stellar molecular outfolw source, IRAS 19134+2131

恒星分子外流源中水脉泽的运动学，IRAS 19134 2131

• 发表时间: 2004
• 期刊: Astronomy and Astrophysics 420
• 作者: Imai;H. et al.
• 通讯作者: H. et al.

The kinematics of water masers in the stellar molecular outflow source, IRAS 19134+2131

恒星分子流出源中水脉泽的运动学，IRAS 19134 2131

• 发表时间: 2004
• 期刊: Astronomy and Astrophysics 420
• 作者: Imai;H. et al.
• 通讯作者: H. et al.

VERA Observation of the W49NH2O Maser Outburst in 2003 October

• DOI: 10.1093/pasj/56.3.l15
• 发表时间: 2004-05
• 期刊: Publications of the Astronomical Society of Japan
• 影响因子: 2.3
• 作者: M. Honma;Y. Choi;T. Bushimata;T. Fujii;T. Hirota;K. Horiai;H. Imai;N. Inomata;J. Ishitsuka;K. Iwadate;T. Jike;O. Kameya;R. Kamohara;Y. Kan-ya;N. Kawaguchi;H. Kobayashi;S. Kuji;T. Kurayama;S. Manabe;T. Miyaji;A. Nakagawa;K. Nakashima;R. Nagayoshi;T. Omodaká;T. Oyama;M. Rioja;S. Sakai;S. Sakakibara;K. Sato;T. Sasao;K. Shibata;R. Shimizu;K. Sora;H. Suda;Y. Tamura;K. Yamashita

Multi-Epoch VERA Observations of OH 43.8-0.1

OH 43.8-0.1 的多历元 VERA 观测

• 发表时间: 2005
• 期刊: Publications of the Astronomical Society of Japan 57
• 作者: Honma;M.;Bushimata;T.;Choi;Y.K.;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.;Kijima;M.;Kobayashi;H.;Kuji;S.;Kurayama;T.;Manabe;S.;Miyaj
• 通讯作者: Miyaj