Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency

Okezuonu Patrick Chinedu; Ogwo Jemima Ngozi

doi:doi:10.11648/j.ijass.20210903.12

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Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency

Okezuonu Patrick Chinedu, Ogwo Jemima Ngozi

Published in International Journal of Astrophysics and Space Science (Volume 9, Issue 3)

Received: 11 October 2021 Accepted: 5 November 2021 Published: 24 November 2021

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Abstract

The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds (ϵ_GMC) is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M_⋆ harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.

Published in	International Journal of Astrophysics and Space Science (Volume 9, Issue 3)
DOI	10.11648/j.ijass.20210903.12
Page(s)	45-50
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Galaxies, Star Formation Efficiency, Cloud Density, Stellar Mass, Gas Mass

References

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Okezuonu Patrick Chinedu, Ogwo Jemima Ngozi. (2021). Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. International Journal of Astrophysics and Space Science, 9(3), 45-50. https://doi.org/10.11648/j.ijass.20210903.12

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ACS Style

Okezuonu Patrick Chinedu; Ogwo Jemima Ngozi. Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. Int. J. Astrophys. Space Sci. 2021, 9(3), 45-50. doi: 10.11648/j.ijass.20210903.12

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AMA Style

Okezuonu Patrick Chinedu, Ogwo Jemima Ngozi. Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. Int J Astrophys Space Sci. 2021;9(3):45-50. doi: 10.11648/j.ijass.20210903.12

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@article{10.11648/j.ijass.20210903.12,
  author = {Okezuonu Patrick Chinedu and Ogwo Jemima Ngozi},
  title = {Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency},
  journal = {International Journal of Astrophysics and Space Science},
  volume = {9},
  number = {3},
  pages = {45-50},
  doi = {10.11648/j.ijass.20210903.12},
  url = {https://doi.org/10.11648/j.ijass.20210903.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijass.20210903.12},
  abstract = {The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds (ϵ_GMC) is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M_⋆ harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.},
 year = {2021}
}

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TY  - JOUR
T1  - Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency
AU  - Okezuonu Patrick Chinedu
AU  - Ogwo Jemima Ngozi
Y1  - 2021/11/24
PY  - 2021
N1  - https://doi.org/10.11648/j.ijass.20210903.12
DO  - 10.11648/j.ijass.20210903.12
T2  - International Journal of Astrophysics and Space Science
JF  - International Journal of Astrophysics and Space Science
JO  - International Journal of Astrophysics and Space Science
SP  - 45
EP  - 50
PB  - Science Publishing Group
SN  - 2376-7022
UR  - https://doi.org/10.11648/j.ijass.20210903.12
AB  - The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds (ϵ_GMC) is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M_⋆ harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.
VL  - 9
IS  - 3
ER  -

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Author Information

Okezuonu Patrick Chinedu

Department of Industrial Physics, Faculty of Physical Science, Abia State University, Uturu, Nigeria
Ogwo Jemima Ngozi

Department of Industrial Physics, Faculty of Physical Science, Abia State University, Uturu, Nigeria

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Okezuonu Patrick Chinedu, Ogwo Jemima Ngozi. (2021). Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. International Journal of Astrophysics and Space Science, 9(3), 45-50. https://doi.org/10.11648/j.ijass.20210903.12

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ACS Style

Okezuonu Patrick Chinedu; Ogwo Jemima Ngozi. Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. Int. J. Astrophys. Space Sci. 2021, 9(3), 45-50. doi: 10.11648/j.ijass.20210903.12

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AMA Style

Okezuonu Patrick Chinedu, Ogwo Jemima Ngozi. Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency. Int J Astrophys Space Sci. 2021;9(3):45-50. doi: 10.11648/j.ijass.20210903.12

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@article{10.11648/j.ijass.20210903.12,
  author = {Okezuonu Patrick Chinedu and Ogwo Jemima Ngozi},
  title = {Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency},
  journal = {International Journal of Astrophysics and Space Science},
  volume = {9},
  number = {3},
  pages = {45-50},
  doi = {10.11648/j.ijass.20210903.12},
  url = {https://doi.org/10.11648/j.ijass.20210903.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijass.20210903.12},
  abstract = {The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds (ϵ_GMC) is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M_⋆ harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.},
 year = {2021}
}

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TY  - JOUR
T1  - Density, Alternative Determinant of Star Formation Efficiency of the Milky Way GMCs: Core Reason for Low Star Formation Efficiency
AU  - Okezuonu Patrick Chinedu
AU  - Ogwo Jemima Ngozi
Y1  - 2021/11/24
PY  - 2021
N1  - https://doi.org/10.11648/j.ijass.20210903.12
DO  - 10.11648/j.ijass.20210903.12
T2  - International Journal of Astrophysics and Space Science
JF  - International Journal of Astrophysics and Space Science
JO  - International Journal of Astrophysics and Space Science
SP  - 45
EP  - 50
PB  - Science Publishing Group
SN  - 2376-7022
UR  - https://doi.org/10.11648/j.ijass.20210903.12
AB  - The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds (ϵ_GMC) is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M_⋆ harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.
VL  - 9
IS  - 3
ER  -

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