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Title: PARALLAXES OF STAR-FORMING REGIONS IN THE OUTER SPIRAL ARM OF THE MILKY WAY

Abstract

We report parallaxes and proper motions of three water maser sources in high-mass star-forming regions in the Outer Spiral Arm of the Milky Way. The observations were conducted with the Very Long Baseline Array as part of Bar and Spiral Structure Legacy Survey and double the number of such measurements in the literature. The Outer Arm has a pitch angle of 14.°9 ± 2.°7 and a Galactocentric distance of 14.1 ± 0.6 kpc toward the Galactic anticenter. The average motion of these sources toward the Galactic center is 10.7 ± 2.1 km s{sup –1} and we see no sign of a significant fall in the rotation curve out to 15 kpc from the Galactic center. The three-dimensional locations of these star-forming regions are consistent with a Galactic warp of several hundred parsecs from the plane.

Authors:
 [1];  [2]; ;  [3]; ; ;  [4]
  1. Research Institute for Time Studies, Yamaguchi University, Yoshida 1677-1, Yamaguchi, Yamaguchi 753-8511 (Japan)
  2. Korea Astronomy and Space Institute, Daedeokdae-ro 776, Yuseong-gu, Daejeon 305-348 (Korea, Republic of)
  3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  4. Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany)
Publication Date:
OSTI Identifier:
22364279
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 800; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMIC RADIO SOURCES; DIAGRAMS; DISTANCE; INCLINATION; MASERS; MASS; MILKY WAY; PROPER MOTION; ROTATION; STAR EVOLUTION; STARS; THREE-DIMENSIONAL CALCULATIONS; WATER

Citation Formats

Hachisuka, K., Choi, Y. K., Reid, M. J., Dame, T. M., Brunthaler, A., Menten, K. M., and Sanna, A. PARALLAXES OF STAR-FORMING REGIONS IN THE OUTER SPIRAL ARM OF THE MILKY WAY. United States: N. p., 2015. Web. doi:10.1088/0004-637X/800/1/2.
Hachisuka, K., Choi, Y. K., Reid, M. J., Dame, T. M., Brunthaler, A., Menten, K. M., & Sanna, A. PARALLAXES OF STAR-FORMING REGIONS IN THE OUTER SPIRAL ARM OF THE MILKY WAY. United States. doi:10.1088/0004-637X/800/1/2.
Hachisuka, K., Choi, Y. K., Reid, M. J., Dame, T. M., Brunthaler, A., Menten, K. M., and Sanna, A. 2015. "PARALLAXES OF STAR-FORMING REGIONS IN THE OUTER SPIRAL ARM OF THE MILKY WAY". United States. doi:10.1088/0004-637X/800/1/2.
@article{osti_22364279,
title = {PARALLAXES OF STAR-FORMING REGIONS IN THE OUTER SPIRAL ARM OF THE MILKY WAY},
author = {Hachisuka, K. and Choi, Y. K. and Reid, M. J. and Dame, T. M. and Brunthaler, A. and Menten, K. M. and Sanna, A.},
abstractNote = {We report parallaxes and proper motions of three water maser sources in high-mass star-forming regions in the Outer Spiral Arm of the Milky Way. The observations were conducted with the Very Long Baseline Array as part of Bar and Spiral Structure Legacy Survey and double the number of such measurements in the literature. The Outer Arm has a pitch angle of 14.°9 ± 2.°7 and a Galactocentric distance of 14.1 ± 0.6 kpc toward the Galactic anticenter. The average motion of these sources toward the Galactic center is 10.7 ± 2.1 km s{sup –1} and we see no sign of a significant fall in the rotation curve out to 15 kpc from the Galactic center. The three-dimensional locations of these star-forming regions are consistent with a Galactic warp of several hundred parsecs from the plane.},
doi = {10.1088/0004-637X/800/1/2},
journal = {Astrophysical Journal},
number = 1,
volume = 800,
place = {United States},
year = 2015,
month = 2
}
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