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http://dx.doi.org/10.5303/JKAS.2010.43.2.041

THE EVOLUTIONARY STAGE OF H II REGION AND SPECTRAL TYPES OF MASSIVE STARS FROM KINEMATICS OF H2O MASERS IN W51 MAIN  

Cho, Jae-Sang (Department of Astronomy, Yonsei University)
Kan-Ya, Yukitoshi (Department of Astronomy, Yonsei University)
Byun, Yong-Ik (Department of Astronomy, Yonsei University)
Kurayama, Tomoharu (Faculty of Science and Engineering, Kagoshima University)
Choi, Yoon-Kyung (Max-Planck-Institut fuer Radioastronomie Auf dem Huegel)
Kim, Mi-Kyoung (Department of Astronomy, Graduate School of Science, The University of Tokyo)
Publication Information
Journal of The Korean Astronomical Society / v.43, no.2, 2010 , pp. 41-54 More about this Journal
Abstract
We report relative proper motion measurements of $H_{2}O$ masers in massive star-forming region W51 Main, based on data sets of VLBI observations for $H_{2}O$ masers at 22 GHz with Japanese VERA telescopes from 2003 to 2006. Data reductions and single-beam imaging analysis are to measure internal kinematics of maser spots and eventually to estimate the three-dimensional kinematics of $H_{2}O$ masers in W51 Main. Average space motions and proper motion measurements of $H_{2}O$ masers are given both graphical and in table formats. We find in this study that W51 Main appears to be associated with hyper-compact H II region with multiple massive proto-stars whose spectral types are of late O.
Keywords
radio lines: stars; stars: formation; ISM: jets and outflows; ISM: kinematics; masers: $H_{2}O$ maser;
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1 Zhang, Q., & Ho, P. T. P. 1997, Dynamical Collapse in W51 Massive Cores: $NH_3$ Observations, ApJ, 488, 241   DOI
2 Zhang, Q., Wang, Y., Pillai, T., & Rathborne, J. 2009, Fragmentation at the Earliest Phase of Massive Star Formation, ApJ, 696, 268   DOI
3 Zinnecker, H., & Yorke, H. W. 2007, Toward Understanding Massive Star Formation, ARA&A, 45, 481   DOI   ScienceOn
4 Purcell, C. R., Longmore, S. N., Burton, M. G., Walsh, A. J., Minier, V., Cunningham, M. R., & Balasubramanyam, R. 2009, Physical and Chemical Conditions in Methanol Maser Selected Hot Cores and UCHII Regions, MNRAS, 394, 323   DOI   ScienceOn
5 Reid, M. J. 2002, Masers from Protostars to Black Holes: Conference Summary, ASPCS, 206, 506
6 Sewilo, M., Chuchwell, E., Krutz, S., Goss, W. M., & Hofner, P. 2004, Broad Radio Recombination Lines from Hypercompact H II Regions, ApJ, 605, 285   DOI
7 Rudolph, A., Welch, W. J., Palmer, P., & Dubrulle, B. 1990, Dynamical Collapse of the W51 Star-Forming Region, ApJ, 363, 528   DOI
8 Sato, M., & the VERA collaboration 2007, Absolute Proper Motions of $H_2O$ Masers away from the Galactic Plane Measured with VERA in the Superbubble Region NGC 281, PASJ, 59, 743   DOI
9 Scott, P. F. 1978, High Resolution Radio Observations of G49.5-0.4 W51, MNRAS, 183, 435   DOI
10 Shepherd, D. 2005, Massive Star Outflows, in Massive Star Birth, IAU Symp., 227, 237
11 Tieftrunk, A. R., Gaume, R. A., Cluassen, M. J., Wilson, T. L., & Johnston, K J. 1997, The H II Molecular Cloud Complex W3 Revisited: Imaging the Radio Continuum Sources Using Multi-Con, Multi-Frequency Observations with the VLA, A&A, 318, 931
12 Torrelles, J. M., Gomez, J. F., Rodriguez, L. F., Curiel, S., Ho, P. T. P., & Garay, G. 1996, The Thermal Radio Jet of Cepheus A HW2 and the Water Maser Distribution at 0 -8pt. Scale (60 AU), ApJ, 457, L107
13 Ulich, B. L., & Has,s R. W. 1976, Absolute Calibration of Millimeter-Wavelength Spectral Lines, ApJS, 30, 247   DOI
14 Wood, D. O. S., & Churchwell, E. 1989, The Morphologies and Physical Properties of Ultracompact H II Regions, ApJS, 69, 831   DOI
15 Yu, K C., Billawala, Y., & Bally, J. 1999, Parsec-Scale CO Outflow and $H_2$ Jets in Barnard 5, ApJ, 118, 2940   DOI
16 Imai, H. 2006, Observational Study on Star Formation with VLBI (Kiyosato: EAYAM 2006)
17 Kurtz, S., Cesaroni, R., Churchwell, E., Hofner, P., & Walmsley, C. M. 2000, Hot Molecular Cores and the Earliest Phases of High-Mass Star Formation, in Protostars and Planets IV, ed. Mannings V., Boss A., Russell S. S. (Tucson: University of Arizona Press), 299
18 Jaffe, D. T., & Martin-Pintdo. 1999, Low-Velocity Ionized Winds from Regions around Young O Stars, ApJ, 520, 162   DOI
19 Kan-ya, Y., & the VERA collaboration 2007, CCcoda - The I/O Library for the Radio Data Reduction System VEDA, BKAS, 32, No.1, 104
20 Kim, K-T., & Koo, B.-C. 2001, Radio Continuum and Recombination Line Study of Ultracompact H II Regions with Extended Envelopes, ApJ, 549, 979   DOI
21 Kurtz, S. 2000, Ultracompact H II Regions: New Challenges, Rev. Mex. AA, 9, 169
22 Krutz, S. 2005, Hypercompact H II Regions, in Massive Star Birth, IAU Symp. 227, 111
23 Lai, S.-P., Crutcher, R. M., Girart, J. M., & Rao, R. 2001, Interferometric Mapping of Magnetic Fields in Star-Forming Regions. I. W51 e1/e2 Molecular Cores, ApJ, 561, 864   DOI
24 Leppanen, K., Liljestrom, T., & Diamond, P. 1998, Submilliarcsecond Linear Polarization Observations of Water Masers in W51 M, ApJ, 507, 909   DOI
25 Liljestrom, T. 1998, Shock Structure of the High-Velocity Water Masers in W49 N, ASPCS, 144, 251
26 Martin, A. H. M. 1972, High Resolution Observations of W51, MNRAS, 157, 31   DOI
27 Pascucci, I., Apai, D., Henning, Th., Stecklum, B., & Brandl, B. 2004, The Hot Core-Ultracompact H II Connection in G10.47+0.03, A&A, 426, 523   DOI   ScienceOn
28 Genzel, R., & Downes, D. 1977, $H_2O$ in the Galaxy: Sites of Newly Formed OB Stars, A&AS, 30, 145
29 Genzel, R., Downes, D., Schneps, M. H., Reid, M. J., Moran, J. M., Kogan L. R., Kostenko, V. I., Matveyenko, L. I., & Ronnang, B. 1981, Proper Motions and Distances of $H_2O$ Maser Sources. II - W51 MAIN, ApJ, 247, 1039   DOI
30 Genzel, R., Downes, D., Moran, J. M., Johnston, K. J., Spencer, J. H., Matveyenko, L. I., Kogan, L. R., Kostenko, V. I., Ronnang, B., Haschick, A. D., Reid, M. J., Walker, R. C., Giuffrida, T. S., Burke, B. F., & Moiseev, I. G. 1979, $H_2O$ in W51 Main - An Expanding Bubble around a Young Massive Star, A&A, 78, 239
31 Gwinn, C. R. 1994, Hypersonic Acceleration and Turbulence of $H_2O$ Masers in W49N, ApJ, 429, 241   DOI
32 Goldader, J. D., & Wynn-Williams, C. G. 1994, Near-Infrared Observations of W51, ApJ, 433, 164   DOI
33 Hofner, P., Krutz S., Churchwell, E., Walmsley, C. M., & Cesaroni, R. 1994, High-Resolution Observations of a New Ammonia Maser Line in G9.62+0.19, ApJ, 429, L85   DOI
34 Honma, M., & the VERA collaboration 2003, First Fringe Detection with VERAs Dual-Beam System and Its Phase-Referencing Capability, PASJ, 55, L57   DOI   ScienceOn
35 Honma, M., & the VERA collaboration 2005, Multi-Epoch VERA Observations of -0.1, PASJ, 57, 595   DOI
36 Iguchi, S., Kurayama, T., Kawaguchi, N., & Kawakami, K. 2005, Gigabit Digital Filter Bank: Digital Backend Subsystem in the VERA Data-Acquisition System, PASJ, 57, 259   DOI
37 Imai, H., Watanabe, T., Omodaka, T., Nishio, M., Kameya, O., Miyaji, T., & Nakajima, J. 2002, 3-D Kinematics of Water Masers in the W 51A Region, PASJ, 54, 741   DOI
38 Imai, H., & the VERA collaboration 2005, Water masers in W51A observed with the VLBI Exploration of Radio Astrometry VERA, in Massive Star Birth: A Crossroads of Astrophysics, IAU Symp. 242, poster section
39 Bally, J., Reipurth, B., & Davis, C. J. 2007, Observations of Jets and Outflows from Young Stars, in Protostars and Planets V, ed. Reipurth B., Jewitt D., Keil K. (Tucson: University of Arizona Press), 215
40 Argon, A. L., Reid M. J., & Menten, K. M. 2002, Full-Polarization Maps of OH Main-Line Masers in the W51 and G351.78-0.54 Star-Forming Regions, IAU Symp., 206, 367
41 Beuther, H., Churchwell, E. B., McKee, C. F., & Tan, J. C. 2007, The Formation of Massive Stars, in Protostars and Planets V, ed. Reipurth B., Jewitt D., Keil K. (Tucson: University of Arizona Press), 165
42 Beuther, H., & Shepherd, D. 2005, Precursors of UCHII Regions & the Evolution of Massive Outflows, A&SSL, 324, 105
43 Cesaroni, R., Churchwell, E., Hofner, P., Walmsley, C. M., & Krutz, S. 1994, Hot Ammonia towards Compact HII Regions, A&A, 288, 903
44 Cheung, A. C., Rank, D. M., & Townes, C. H. 1969, Detection of Water in Interstellar Regions by its Microwave Radiation, Nature, 221, 626   DOI
45 Chikada, Y., Kawaguchi, N., Inoue, M., Morimoto, M., Kobayashi, H., & Mattori S. 1991, The VSOP Correlator, in Frontiers of VLBI, Tokyo: Universal Academy Press, 79
46 Churchwell, E. 2002, Ultra-Compact HII Regions and Massive Star Formation, ARA&A, 40, 27   DOI   ScienceOn
47 De Wit, W. J., Testi, L., Palla, F., & Zinnecker, H. 2005, The Origin of Massive O-Type Field Stars: II. Field O Stars as Runaways, A&A, 437, 247   DOI   ScienceOn
48 Elmegreen, B. G., & Lada, C. J. 1977, Sequential Formation of Subgroups in OB Associations, ApJ, 214, 725   DOI
49 Fish, V. L., & Reid, M. J. 2007, Proper Motions of OH Masers and Magnetic Fields in Massive Star-Forming Regions, ApJ, 670, 1159   DOI
50 Fomalont, E. B., & Weliachew, L. 1973, Interferometric Observations of Formaldehyde Absorption in Front of Strong Galactic Sources, ApJ, 181, 781   DOI
51 Arce, H. G., Shepherd, D., Gueth, F., Lee, C.-F., Bachiller, R., Rosen, A., & Beuther, H. 2007, Molecular Outflows in Low- and High-Mass Star-Forming Regions, in Protostars and Planets V, ed. Reipurth B., Jewitt D., Keil K. (Tucson: University of Arizona Press), 245