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Galactic Structure

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Galactic Radio Astronomy

Part of the book series: Lecture Notes in Physics ((LNP,volume 935))

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Abstract

The Milky Way is one of the most typical spiral galaxies, resembling the Andromeda galaxy (M31), and is composed of a nucleus nesting a supermassive black hole, a spheroidal central bulge composed of old stars, flat stellar disk filled with interstellar gas superposed by spiral arms, and a huge dark halo extending half-way to the neighboring galaxy.

The galaxy is the nearest, hence most extensively observed galaxy in detail, however, the special position of the observers located inside the object always poses difficulty in knowing the three-dimensional structure. This difficulty, in turn, forced astronomers to develop sophisticated techniques of observation and analysis. The difficulty is overcome by observing a galaxy from outside, which is in fact extensively done for external galaxies.

In this chapter we describe the method to derive the dynamical structure of galaxies based on the Newtonian theory of gravitation. We learn various methods to measure the mass distributions, and the methods are applied to observed rotation curves of galaxies.

The original version of this chapter was published without printing chapter abstract. The abstracts for each chapter are updated in the front matter in the current version of the book. An erratum to this chapter can be found at https://doi.org/10.1007/978-981-10-3445-9_7.

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References

  1. Bennett, C.L., Larson, D., Weiland, J.L., et al.: Nine-year Wilkinson Microwave Anisotropy Probe (WMAP) observations: Final maps and results. ApJS 208, 20 (2013). [Hubble constant WMAP9y]

    Google Scholar 

  2. Binney, J. Tremaine, S.: Galactic Dynamics, p. 146. Princeton University Press, Princeton (1987). [Galactic dynamics]

    Google Scholar 

  3. Dame, T.M., Hartman, D., Thaddeus, P.: The Milky Way in molecular clouds: a new complete CO survey. ApJ 547, 792 (2001). [CO in the Galaxy]

    Google Scholar 

  4. Haslam, C.G.T., Salter, C.J., Stoffel, H., & Wilson, W.E.: A 408 MHz all-sky continuum survey. II – the atlas of contour maps. AA Suppl. 47, 1 (1982)

    Google Scholar 

  5. Hou, L.G., Han, J.L.: The observed spiral structure of the Milky Way. AA 569, 125 (2014). [HII regions]

    Google Scholar 

  6. Honma, M., Nagayama, T., & Sakai, N.: Determining dynamical parameters of the Milky Way Galaxy based on high-accuracy radio astrometry. PASJ 67, 70 (2015). [Galactic constants by VERA]

    Google Scholar 

  7. Kalberla, P.M.W., Burton, W.B., Hartmann, D., et al. The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI. Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections. AA 440, 775 (2005). [All sky HI]

    Google Scholar 

  8. Matsunaga, N., Kawadu, T., Nishiyama, S., et al.: A near-infrared survey of Miras and the distance to the Galactic Centre. MNRAS 399, 1709 (2009)

    Article  ADS  Google Scholar 

  9. Miyamoto, M., Nagai, R.: Three-dimensional models for the distribution of mass in galaxies. PASJ 27, 533 (1975). [Galaxy potential]

    Google Scholar 

  10. Nakanishi, H., Sofue, Y.: Three-dimensional distribution of the ISM in the Milky Way Galaxy: II. The molecular gas disk. PASJ 58, 847 (2006). [MW HI and CO 3D map]

    Google Scholar 

  11. Nakanishi, H., Sofue, Y.: Three-dimensional distribution of the ISM in the Milky Way Galaxy. IV. 3D molecular fraction and Galactic-scale H I-to-H2 transition. PASJ 68, 5 (2016). [ibid]

    Google Scholar 

  12. Navarro, J.F., Frenk, C.S., White, S.D.M.: A universal density profile from hierarchical clustering. ApJ 490, 493 (1997). [Dark halo potential]

    Google Scholar 

  13. Oka, T., Hasegawa, T., Sato, F., Tsuboi, M., Miyazaki, A.: A large-scale CO survey of the galactic center. ApJS 118, 455 (1998). [CO in the GC]

    Google Scholar 

  14. Oort, J.H., Kerr, F.T., Westerhout, G.: The galactic system as a spiral nebula (Council Note). MNRAS 118, 379 (1958). [HI view of the MW]

    Google Scholar 

  15. Pavlović, M.Z., Urošević, D., Vukotić, B., Arbutina, B., Göker, Ü.D.: The radio surface-brightness-to-diameter relation for galactic supernova remnants: sample selection and robust analysis with various fitting offsets. ApJS 204, 4 (2013)

    Article  ADS  Google Scholar 

  16. Sofue, Y.: The mass distribution and rotation curve in the galaxy. In: Gilmore, G. (ed.) Planets, Stars and Stellar Systems, vol. 5, chap. 19 Springer, Dordrecht (2013). [Rotation curves]

    Google Scholar 

  17. Sofue, Y.: Rotation and mass in the Milky Way and spiral galaxies. PASJ 69, 1 (2017). https://arxiv.org/abs/1608.08350. [Review of RC and Mass in MW and galaxies]

  18. Sofue, Y., Rubin, V.C.: Rotation curves of spiral galaxies. ARAA 39, 137 (2001). [RC review]

    Google Scholar 

  19. Tully B., Fisher J.R.: A new method of determining distances to galaxies. AA 64, 661 (1977). [Tully-Fisher relation]

    Google Scholar 

  20. Tutui, Y., Sofue, Y.: Effects of galaxy interaction on the Tully-Fisher relation: CO VS HI linewidths. AA 326, 915 (1997). [CO TFR]

    Google Scholar 

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Authors and Affiliations

  1. Institute of Astronomy, The University of Tokyo, Mitaka, Tokyo, Japan

    Yoshiaki Sofue

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  1. Yoshiaki Sofue
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Sofue, Y. (2017). Galactic Structure. In: Galactic Radio Astronomy. Lecture Notes in Physics, vol 935. Springer, Singapore. https://doi.org/10.1007/978-981-10-3445-9_4

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