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Deep Near-Infrared Imaging and Photometry of the Antennae Galaxies with WIRC

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 نشر من قبل Bernhard Brandl
 تاريخ النشر 2005
  مجال البحث فيزياء
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We present deep near-infrared images of the Antennae galaxies, taken with the Palomar Wide-Field Infrared Camera WIRC. The images cover a 4.33 x 4.33 (24.7kpc x 24.7kpc) area around the galaxy interaction zone. We derive J and K_s band photometric fluxes for 172 infrared star clusters, and discuss details of the two galactic nuclei and the overlap region. We also discuss the properties of a subset of 27 sources which have been detected with WIRC, HST and the VLA. The sources in common are young clusters of less than 10 Myr, which show no correlation between their infrared colors and 6 cm radio properties. These clusters cover a wide range in infrared color due to extinction and evolution. The average extinction is about A_V~2 mag while the reddest clusters may be reddened by up to 10 magnitudes.


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