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Detecting the disruption of dark-matter halos with stellar streams

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 نشر من قبل Jo Bovy
 تاريخ النشر 2015
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Jo Bovy




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Narrow stellar streams in the Milky Way halo are uniquely sensitive to dark-matter subhalos, but many of these subhalos may be tidally disrupted. I calculate the interaction between stellar and dark-matter streams using analytical and $N$-body calculations, showing that disrupting objects can be detected as low-concentration subhalos. Through this effect, we can constrain the lumpiness of the halo as well as the orbit and present position of individual dark-matter streams. This will have profound implications for the formation of halos and for direct and indirect-detection dark-matter searches.



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