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Title: MOND Calculations of Bulk Dispersions and Radial Dispersion Profiles of Milky Way and Andromeda Dwarf Spheroidal Galaxies

Abstract

We present a new computational method for calculating the motion of stars in a dwarf spheroidal galaxy (dSph) that can use either Newtonian gravity or Modified Newtonian Dynamics (MOND). In our model, we explicitly calculate the motion of several thousand stars in a spherically symmetric gravitational potential, and we statistically obtain both the line-of-sight bulk velocity dispersion and dispersion profile. Our results for MOND calculated bulk dispersions for Local Group dSph’s agree well with previous calculations and observations. Our MOND calculated dispersion profiles are compared with the observations of Walker et al. for Milky Way dSph’s, and we present calculated dispersion profiles for a selection of Andromeda dSph’s.

Authors:
; ; ; ; ;  [1]
  1. Department of Physics Miami University Oxford, OH 45056 (United States)
Publication Date:
OSTI Identifier:
22663908
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DISPERSIONS; GRAVITATION; MILKY WAY; NONLUMINOUS MATTER; SPHERICAL CONFIGURATION; STARS; SYMMETRY; VELOCITY

Citation Formats

Alexander, S. G., Walentosky, M. J., Messinger, Justin, Staron, Alexander, Blankartz, Benjamin, and Clark, Tristan. MOND Calculations of Bulk Dispersions and Radial Dispersion Profiles of Milky Way and Andromeda Dwarf Spheroidal Galaxies. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/2/233.
Alexander, S. G., Walentosky, M. J., Messinger, Justin, Staron, Alexander, Blankartz, Benjamin, & Clark, Tristan. MOND Calculations of Bulk Dispersions and Radial Dispersion Profiles of Milky Way and Andromeda Dwarf Spheroidal Galaxies. United States. doi:10.3847/1538-4357/835/2/233.
Alexander, S. G., Walentosky, M. J., Messinger, Justin, Staron, Alexander, Blankartz, Benjamin, and Clark, Tristan. Wed . "MOND Calculations of Bulk Dispersions and Radial Dispersion Profiles of Milky Way and Andromeda Dwarf Spheroidal Galaxies". United States. doi:10.3847/1538-4357/835/2/233.
@article{osti_22663908,
title = {MOND Calculations of Bulk Dispersions and Radial Dispersion Profiles of Milky Way and Andromeda Dwarf Spheroidal Galaxies},
author = {Alexander, S. G. and Walentosky, M. J. and Messinger, Justin and Staron, Alexander and Blankartz, Benjamin and Clark, Tristan},
abstractNote = {We present a new computational method for calculating the motion of stars in a dwarf spheroidal galaxy (dSph) that can use either Newtonian gravity or Modified Newtonian Dynamics (MOND). In our model, we explicitly calculate the motion of several thousand stars in a spherically symmetric gravitational potential, and we statistically obtain both the line-of-sight bulk velocity dispersion and dispersion profile. Our results for MOND calculated bulk dispersions for Local Group dSph’s agree well with previous calculations and observations. Our MOND calculated dispersion profiles are compared with the observations of Walker et al. for Milky Way dSph’s, and we present calculated dispersion profiles for a selection of Andromeda dSph’s.},
doi = {10.3847/1538-4357/835/2/233},
journal = {Astrophysical Journal},
number = 2,
volume = 835,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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