Enigmatic velocity dispersions of ultradiffuse galaxies in light of modified gravity theories and the radial acceleration relation

  title={Enigmatic velocity dispersions of ultradiffuse galaxies in light of modified gravity theories and the radial acceleration relation},
  author={Tousif Islam},
  journal={Physical Review D},
  • Tousif Islam
  • Published 22 October 2019
  • Physics
  • Physical Review D
Recent observations of anomalous line-of-sight velocity dispersions of two ultra-diffuse galaxies (UDGs) provide a stringent test for modified gravity theories. While NGC 1052-DF2 exhibits an extremely low dispersion value ($\sigma \sim 7.8_{-2.2}^{+5.6}$ km/s), the reported dispersion value for NGC 1052-DF44 is quite high ($\sigma \sim 41.0 \pm 8$ km/s). For DF2, the dynamical mass is almost equal to the luminous mass suggesting the galaxy have little to no `dark matter' in $\Lambda$CDM… Expand

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