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تسجيل مستخدم جديدScience with an ngVLA: Characterizing Feedback Through Molecular Outflows Across Cosmic Time
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Justin Spilker
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Galactic winds are ubiquitously observed in galaxies both locally and in the high-redshift Universe. While these winds span many orders of magnitude in both temperature and density, observations of nearby galaxies show that the cold molecular phase tends to dominate both the mass and momentum carried. The capabilities of the ngVLA for the study of molecular outflows at low redshift are described elsewhere in this Volume; here we focus on the ability of the ngVLA to detect and image such outflows in the high-redshift Universe via deep observations of low-J transitions of the CO molecule. The ngVLA is capable of detecting molecular outflows from typical galaxies on the star-forming sequence with log(Mstar/Msun) >~ 10.5 to z~3, and galaxies with higher star formation rates to beyond z~4. The ngVLA will enable an understanding of the feedback processes that shape galaxies throughout the epoch of galaxy assembly when the bulk of the stars in the Universe were formed. While the emission associated with outflows is faint in comparison to the emission from the galaxy, deep observations are also required for high-resolution dynamical studies, allowing for the routine simultaneous detection and imaging of the outflows.
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