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A Dearth of Dark Matter in Ordinary Elliptical Galaxies

Aaron J. Romanowsky·Nigel D. Douglas·Magda Arnaboldi·Konrad Kuijken·Michael R. Merrifield·Nicola R. Napolitano·Massimo Capaccioli·Kenneth C. Freeman
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Abstract

The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies have been studied using the Planetary Nebula Spectrograph. The galaxies' velocity dispersion profiles are found to decline with radius; dynamical modeling of the data indicates the presence of little if any dark matter in these galaxies' halos. This surprising result conflicts with findings in other galaxy types, and poses a challenge to current galaxy formation theories.

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BibTeXRIS

Aaron J. Romanowsky, Nigel D. Douglas, Magda Arnaboldi, Konrad Kuijken, Michael R. Merrifield, Nicola R. Napolitano, Massimo Capaccioli, Kenneth C. Freeman. 2003-08-28. A Dearth of Dark Matter in Ordinary Elliptical Galaxies. https://doi.org/10.1126/%3D

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