Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009aas...21344513r&link_type=abstract
American Astronomical Society, AAS Meeting #213, #445.13; Bulletin of the American Astronomical Society, Vol. 41, p.330
Astronomy and Astrophysics
Astronomy
Scientific paper
Detailed investigations of the molecular interstellar medium in quasar host galaxies at the highest redshifts are important for our understanding of the formation and evolution of quasars and their bulges, since it is the molecular gas out of which stars form. I will present the first successful observations of molecular gas at z>4 obtained with the Combined Array for Research in Millimeter-wave Astronomy (CARMA). This study helps to constrain the physical properties in two key active galactic nucleus (AGN)-starburst systems in the early universe. The z=4.41 quasar BRI1335-0417 is currently undergoing a massive, "wet" (gas-rich) merger, leading to the formation of its host galaxy, the active growth of its central black hole, and the buildup of its stellar bulge. The detection of CO(J=4-3) emission in this system helps to constrain its molecular gas excitation, in particular the gas density and temperature. The z=3.91 quasar APM08279+5255 is in an even more extreme phase of its evolution, as shown by its extreme molecular gas excitation. The detection of highly excited emission from the high-level J=6-5 transitions of the dense, star-forming gas tracers HCN and HCO+ is very unusual, and suggests that the dense gas in this system is substantially radiatively (rather than collisionally) excited. This is consistent with the finding that the gas and dust reservoirs in this galaxy are very compact and warm, and that the AGN is highly luminous (even among type-1 quasars), indicating rapid, co-eval growth of the black hole and the stellar component. These observations highlight the importance of understanding the molecular gas properties of key targets among the earliest galaxies to place them in an evolutionary context, and pave the way for future observations with the Expanded Very Large Array (EVLA) and the Atacama Large Millimeter/submillimeter Array (ALMA).
DR acknowledges funding from NASA/STScI through Hubble Fellowship HST-HF-01212.01-A.
No associations
LandOfFree
The Molecular Gas Reservoirs in Quasar Host Galaxies at Redshift 4: First Constraints from CARMA does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Molecular Gas Reservoirs in Quasar Host Galaxies at Redshift 4: First Constraints from CARMA, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Molecular Gas Reservoirs in Quasar Host Galaxies at Redshift 4: First Constraints from CARMA will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1704351