Kavli Affiliate: John D. Silverman
| First 5 Authors: Qing-Hua Tan, Emanuele Daddi, Benjamin Magnelli, Camila A. Correa, Frédéric Bournaud
| Summary:
The majority of stars in today’s Universe reside within spheroids, which are
bulges of spiral galaxies and elliptical galaxies. Their formation is still an
unsolved problem. Infrared/submm-bright galaxies at high redshifts have long
been suspected to be related to spheroids formation. Proving this connection
has been hampered so far by heavy dust obscuration when focusing on their
stellar emission or by methodologies and limited signal-to-noise ratios when
looking at submm wavelengths. Here we show that spheroids are directly
generated by star formation within the cores of highly luminous starburst
galaxies in the distant Universe. This follows from the ALMA submillimeter
surface brightness profiles which deviate significantly from those of
exponential disks, and from the skewed-high axis-ratio distribution. The
majority of these galaxies are fully triaxial rather than flat disks: the ratio
of the shortest to the longest of their three axes is half, on average, and
increases with spatial compactness. These observations, supported by
simulations, reveal a cosmologically relevant pathway for in-situ spheroid
formation through starbursts likely preferentially triggered by interactions
(and mergers) acting on galaxies fed by non-co-planar gas accretion streams.
| Search Query: ArXiv Query: search_query=au:”John D. Silverman”&id_list=&start=0&max_results=3