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Herschel-SPIRE observations of the disturbed galaxy NGC4438

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 نشر من قبل Luca Cortese Dr.
 تاريخ النشر 2010
  مجال البحث فيزياء
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We present Herschel-SPIRE observations of the perturbed galaxy NGC4438 in the Virgo cluster. These images reveal the presence of extra-planar dust up to ~4-5 kpc away from the galaxys disk. The dust closely follows the distribution of the stripped atomic and molecular hydrogen, supporting the idea that gas and dust are perturbed in a similar fashion by the cluster environment. Interestingly, the extra-planar dust lacks a warm temperature component when compared to the material still present in the disk, explaining why it was missed by previous far-infrared investigations. Our study provides evidence for dust stripping in clusters of galaxies and illustrates the potential of Herschel data for our understanding of environmental effects on galaxy evolution.



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