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arXiv · 0808.1789

The NGC 672 and NGC 784 Galaxy Groups: Evidence for Galaxy Formation and Growth Along a Nearby Dark Matter Filament

Adi Zitrin·Noah Brosch
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Abstract

(Abridged): We present U, B, V, R, I, H-alpha and NUV photometry of 14 galaxies in the very local Universe (within 10 Mpc that are dwarf irregular galaxies (dIrr), are at low redshift (51 1-10 Gyr) and one "young" population (<30 Myr) with the recent SF bursts occurring a few to a few 10s of Myr ago, arguing for synchronicity in star formation in these objects. We propose that the ~synchronous star formation in all objects is caused by the accretion of cold gas from intergalactic space onto dark matter haloes arranged along a filament threading the void where these dwarf galaxies reside and point out this galaxy sample as an ideal target to study hierarchical clustering and galaxy formation among very nearby objects.

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Adi Zitrin, Noah Brosch. 2008-08-13. The NGC 672 and NGC 784 Galaxy Groups: Evidence for Galaxy Formation and Growth Along a Nearby Dark Matter Filament. https://doi.org/10.1111/j.1365-2966.2008.13786.x

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