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Title: Trigonometric distance and proper motion of IRAS 20056+3350: a massive star-forming region on the solar circle

Abstract

We report our measurement of the trigonometric distance and proper motion of IRAS 20056+3350, obtained from the annual parallax of H{sub 2}O masers. Our distance of D=4.69{sub −0.51}{sup +0.65} kpc, which is 2.8 times larger than the near kinematic distance adopted in the literature, places IRAS 20056+3350 at the leading tip of the Local arm and proximal to the solar circle. Using our distance, we reevaluate past observations to reveal IRAS 20056+3350 as a site of massive star formation at a young stage of evolution. This result is consistent with the spectral energy distribution of the source evaluated with published photometric data from UKIDSS, WISE, AKARI, IRAS, and the submillimeter continuum. Both analytical approaches reveal the luminosity of the region to be 2.4 × 10{sup 4} L {sub ☉}, and suggest that IRAS 20056+3350 is forming an embedded star of ≥16 M {sub ☉}. We estimated the proper motion of IRAS 20056+3350 to be (μ{sub α}cos δ, μ{sub δ}) = (–2.62 ± 0.33, –5.65 ± 0.52) mas yr{sup –1} from the group motion of H{sub 2}O masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, Ω{sub 0} = 29.75more » ± 2.29 km s{sup –1} kpc{sup –1}, which is consistent with the values obtained for other tangent point and solar circle objects.« less

Authors:
; ; ; ;  [1];  [2];  [3];  [4]
  1. Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Kôrimoto, Kagoshima, Kagoshima 890-0065 (Japan)
  2. Mizusawa VLBI Observatory, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
  3. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
  4. Mizusawa VLBI Observatory, National Astronomical Observatory of Japan, 2-12 Hoshi-ga-oka, Mizusawa-ku, Oshu, Iwate 023-0861 (Japan)
Publication Date:
OSTI Identifier:
22370043
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 797; 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; ANGULAR VELOCITY; DISTANCE; ENERGY SPECTRA; GALAXIES; LUMINOSITY; MASERS; PROPER MOTION; ROTATION; STAR EVOLUTION; SUN; WATER

Citation Formats

Burns, Ross A., Handa, Toshihiro, Omodaka, Toshihiro, Nakagawa, Akiharu, Nakanishi, Hiroyuki, Nagayama, Takumi, Hayashi, Masahiko, and Shizugami, Makoto, E-mail: RossBurns88@MilkyWay.sci.Kagoshima-u.ac.jp. Trigonometric distance and proper motion of IRAS 20056+3350: a massive star-forming region on the solar circle. United States: N. p., 2014. Web. doi:10.1088/0004-637X/797/1/39.
Burns, Ross A., Handa, Toshihiro, Omodaka, Toshihiro, Nakagawa, Akiharu, Nakanishi, Hiroyuki, Nagayama, Takumi, Hayashi, Masahiko, & Shizugami, Makoto, E-mail: RossBurns88@MilkyWay.sci.Kagoshima-u.ac.jp. Trigonometric distance and proper motion of IRAS 20056+3350: a massive star-forming region on the solar circle. United States. doi:10.1088/0004-637X/797/1/39.
Burns, Ross A., Handa, Toshihiro, Omodaka, Toshihiro, Nakagawa, Akiharu, Nakanishi, Hiroyuki, Nagayama, Takumi, Hayashi, Masahiko, and Shizugami, Makoto, E-mail: RossBurns88@MilkyWay.sci.Kagoshima-u.ac.jp. Wed . "Trigonometric distance and proper motion of IRAS 20056+3350: a massive star-forming region on the solar circle". United States. doi:10.1088/0004-637X/797/1/39.
@article{osti_22370043,
title = {Trigonometric distance and proper motion of IRAS 20056+3350: a massive star-forming region on the solar circle},
author = {Burns, Ross A. and Handa, Toshihiro and Omodaka, Toshihiro and Nakagawa, Akiharu and Nakanishi, Hiroyuki and Nagayama, Takumi and Hayashi, Masahiko and Shizugami, Makoto, E-mail: RossBurns88@MilkyWay.sci.Kagoshima-u.ac.jp},
abstractNote = {We report our measurement of the trigonometric distance and proper motion of IRAS 20056+3350, obtained from the annual parallax of H{sub 2}O masers. Our distance of D=4.69{sub −0.51}{sup +0.65} kpc, which is 2.8 times larger than the near kinematic distance adopted in the literature, places IRAS 20056+3350 at the leading tip of the Local arm and proximal to the solar circle. Using our distance, we reevaluate past observations to reveal IRAS 20056+3350 as a site of massive star formation at a young stage of evolution. This result is consistent with the spectral energy distribution of the source evaluated with published photometric data from UKIDSS, WISE, AKARI, IRAS, and the submillimeter continuum. Both analytical approaches reveal the luminosity of the region to be 2.4 × 10{sup 4} L {sub ☉}, and suggest that IRAS 20056+3350 is forming an embedded star of ≥16 M {sub ☉}. We estimated the proper motion of IRAS 20056+3350 to be (μ{sub α}cos δ, μ{sub δ}) = (–2.62 ± 0.33, –5.65 ± 0.52) mas yr{sup –1} from the group motion of H{sub 2}O masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, Ω{sub 0} = 29.75 ± 2.29 km s{sup –1} kpc{sup –1}, which is consistent with the values obtained for other tangent point and solar circle objects.},
doi = {10.1088/0004-637X/797/1/39},
journal = {Astrophysical Journal},
number = 1,
volume = 797,
place = {United States},
year = {Wed Dec 10 00:00:00 EST 2014},
month = {Wed Dec 10 00:00:00 EST 2014}
}
  • We present observations of 3.6 cm continuum and water maser emission toward the high-mass star-forming region IRAS 06061+2151 (AFGL 5182), made at {approx}0.''3 and {approx}0.''1 resolution, respectively, using the Very Large Array (VLA) in the A configuration. Continuum and maser emission are not detected toward the center of AFGL 5182. However, we detected two groups of continuum sources located {approx}12'' and {approx}3' to the west and northeast of AFGL 5182, respectively. The first group, labeled as the G188.79+1.03 complex, is composed of three continuum sources in a region of about 6'' x 10'', while the second group, associated with themore » source G188.77+1.07, is composed of at least two continuum sources in a region {approx}1'' in diameter. The physical parameters estimated, based on the morphology and the continuum emission, suggest that all the continuum sources in both groups are ultracompact H II regions, associated with ZAMS B-type stars. Water maser emission is only detected toward the compact source VLA N2, which is located in the G188.79+1.03 complex. Accuracy in the relative positions between the radio continuum source and the water masers is of the order of 15 mas. In addition, the observed spatial and kinematical distribution of the water maser features has remained stable for several years, and we confirm that they are tracing a bipolar outflow, where the best candidate of the source powering the water masers and the outflow is VLA 2N.« less
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  • We present results from Chandra ACIS-I and Karl G. Jansky Very Large Array 6 cm continuum observations of the IRAS 20126+4104 massive star-forming region. We detect 150 X-ray sources within the 17′ × 17′ ACIS-I field, and a total of 13 radio sources within the 9.′2 primary beam at 4.9 GHz. Among these observtions are the first 6 cm detections of the central sources reported by Hofner et al., namely, I20N1, I20S, and I20var. A new variable radio source is also reported. Searching the 2MASS archive, we identified 88 near-infrared (NIR) counterparts to the X-ray sources. Only four of the X-raymore » sources had 6 cm counterparts. Based on an NIR color–color analysis and on the Besançon simulation of Galactic stellar populations, we estimate that approximately 80 X-ray sources are associated with this massive star-forming region. We detect an increasing surface density of X-ray sources toward the massive protostar and infer the presence of a cluster of at least 43 young stellar objects within a distance of 1.2 pc from the massive protostar.« less
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