%0 Journal Article
%T Measurements of the Dark Matter Mass, Temperature and Spin
%A Bruce Hoeneisen
%J International Journal of Astronomy and Astrophysics
%P 184-202
%@ 2161-4725
%D 2024
%I Scientific Research Publishing
%R 10.4236/ijaa.2024.143012
%X We summarize several measurements of the dark matter temperature-to-mass ratio, or equivalently, of the comoving root-mean-square thermal velocity of warm dark matter particles <math display='inline' xmlns='http://www.w3.org/1998/Math/MathML'>
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. The most reliable determination of this parameter comes from well measured rotation curves of dwarf galaxies by the LITTLE THINGS collaboration: <math display='inline' xmlns='http://www.w3.org/1998/Math/MathML'>
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. Complementary and consistent measurements are obtained from rotation curves of spiral galaxies measured by the SPARC collaboration, density runs of giant elliptical galaxies, galaxy ultra-violet luminosity distributions, galaxy stellar mass distributions, first galaxies, and reionization. Having measured <math display='inline' xmlns='http://www.w3.org/1998/Math/MathML'>
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, we then embark on a journey to the past that leads to a consistent set of measured dark matter properties, including mass, temperature and spin.
%K Warm Dark Matter
%K Dwarf Galaxies
%K Spiral Galaxies
%K Elliptical Galaxies
%K Galaxy Distributions
%K First Galaxies
%K Reionization
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=135535