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A Companion Galaxy to the Post-Starburst Quasar UN J1025-0040

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 نشر من قبل Gabriela Canalizo
 تاريخ النشر 1999
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Gabriela Canalizo




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UN J1025-0040 is a quasar at z = 0.6344 that shows an extremely bright post starburst population of age ~ 400 Myr (Brotherton et al. 1999). Images of UN J1025-0040 show a nearly stellar object 4.2 arcseconds SSW of the quasar. We present imaging and spectroscopy that confirm that this object is a companion galaxy at redshift z = 0.6341. We estimate an age of ~ 800 Myr for the dominant stellar population in the companion. The companion appears to be interacting with the quasar host galaxy, and this interaction may have triggered both the starburst and the quasar activity in UN J1025-0040.



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