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Title: A POSSIBLE EXTENSION OF THE SCUTUM-CENTAURUS ARM INTO THE OUTER SECOND QUADRANT

Abstract

Combining H I data from the Canadian Galactic Plane Survey and CO data from the Milky Way Imaging Scroll Painting project, we have identified a new segment of a spiral arm between Galactocentric radii of 15 and 19 kpc that apparently lies beyond the Outer Arm in the second Galactic quadrant. Over most of its length, the arm is 400-600 pc thick in z. The new arm appears to be the extension of the distant arm recently discovered by Dame and Thaddeus as well as the Scutum-Centaurus Arm into the outer second quadrant. Our current survey identified a total of 72 molecular clouds with masses on the order of 10{sup 2}-10{sup 4} M {sub ☉} that probably lie in the new arm. When all of the available data from the CO molecular clouds are fit, the best-fitting spiral model gives a pitch angle of 9.°3 ± 0.°7.

Authors:
; ; ; ; ; ;  [1]
  1. Purple Mountain Observatory and Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Nanjing 210008 (China)
Publication Date:
OSTI Identifier:
22364693
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal Letters
Additional Journal Information:
Journal Volume: 798; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 2041-8205
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CARBON MONOXIDE; CLOUDS; INCLINATION; LENGTH; MASS; MILKY WAY; MOLECULES

Citation Formats

Sun, Yan, Xu, Ye, Yang, Ji, Li, Fa-Cheng, Du, Xin-Yu, Zhang, Shao-Bo, and Zhou, Xin. A POSSIBLE EXTENSION OF THE SCUTUM-CENTAURUS ARM INTO THE OUTER SECOND QUADRANT. United States: N. p., 2015. Web. doi:10.1088/2041-8205/798/2/L27.
Sun, Yan, Xu, Ye, Yang, Ji, Li, Fa-Cheng, Du, Xin-Yu, Zhang, Shao-Bo, & Zhou, Xin. A POSSIBLE EXTENSION OF THE SCUTUM-CENTAURUS ARM INTO THE OUTER SECOND QUADRANT. United States. https://doi.org/10.1088/2041-8205/798/2/L27
Sun, Yan, Xu, Ye, Yang, Ji, Li, Fa-Cheng, Du, Xin-Yu, Zhang, Shao-Bo, and Zhou, Xin. 2015. "A POSSIBLE EXTENSION OF THE SCUTUM-CENTAURUS ARM INTO THE OUTER SECOND QUADRANT". United States. https://doi.org/10.1088/2041-8205/798/2/L27.
@article{osti_22364693,
title = {A POSSIBLE EXTENSION OF THE SCUTUM-CENTAURUS ARM INTO THE OUTER SECOND QUADRANT},
author = {Sun, Yan and Xu, Ye and Yang, Ji and Li, Fa-Cheng and Du, Xin-Yu and Zhang, Shao-Bo and Zhou, Xin},
abstractNote = {Combining H I data from the Canadian Galactic Plane Survey and CO data from the Milky Way Imaging Scroll Painting project, we have identified a new segment of a spiral arm between Galactocentric radii of 15 and 19 kpc that apparently lies beyond the Outer Arm in the second Galactic quadrant. Over most of its length, the arm is 400-600 pc thick in z. The new arm appears to be the extension of the distant arm recently discovered by Dame and Thaddeus as well as the Scutum-Centaurus Arm into the outer second quadrant. Our current survey identified a total of 72 molecular clouds with masses on the order of 10{sup 2}-10{sup 4} M {sub ☉} that probably lie in the new arm. When all of the available data from the CO molecular clouds are fit, the best-fitting spiral model gives a pitch angle of 9.°3 ± 0.°7.},
doi = {10.1088/2041-8205/798/2/L27},
url = {https://www.osti.gov/biblio/22364693}, journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 2,
volume = 798,
place = {United States},
year = {Sat Jan 10 00:00:00 EST 2015},
month = {Sat Jan 10 00:00:00 EST 2015}
}