%0 Generic %1 geach2012molecular %A Geach, James E. %A Papadopoulos, Padelis P. %D 2012 %K alma emission line survey %T Molecular and atomic line surveys of galaxies I: the dense, star-forming phase as a beacon %U http://arxiv.org/abs/1206.4693 %X We predict the space density of molecular gas reservoirs in the Universe, and place a lower limit on the number counts of carbon monoxide (CO), hydrogen cyanide (HCN) molecular and CII atomic emission lines in blind redshift surveys in the submillimeter-centimeter spectral regime. Our model uses: (a) recently available HCN Spectral Line Energy Distributions (SLEDs) of local Luminous Infrared Galaxies (LIRGs, L_IR>10^11 L_sun), (b) a value for epsilon=SFR/M_dense(H_2) provided by new developments in the study of star formation feedback on the interstellar medium and (c) a model for the evolution of the infrared luminosity density. Minimal 'emergent' CO SLEDs from the dense gas reservoirs expected in all star-forming systems in the Universe are then computed from the HCN SLEDs since warm, HCN-bright gas will necessarily be CO-bright, with the dense star-forming gas phase setting an obvious minimum to the total molecular gas mass of any star-forming galaxy. We include CII as the most important of the far-infrared cooling lines. Optimal blind surveys with the Atacama Large Millimeter Array (ALMA) could potentially detect very distant (z~10-12) CII emitters in the >ULIRG galaxy class at a rate of ~0.1-1 per hour (although this prediction is strongly dependent on the star formation and enrichment history at this early epoch), whereas the (high-frequency) Square Kilometer Array (SKA) will be capable of blindly detecting z>3 low-J CO emitters at a rate of ~40-70 per hour. The CII line holds special promise for the detection of metal-poor systems with extensive reservoirs of CO-dark molecular gas where detection rates with ALMA can reach up to 2-7 per hour in Bands 4-6.

@misc{geach2012molecular, abstract = {We predict the space density of molecular gas reservoirs in the Universe, and place a lower limit on the number counts of carbon monoxide (CO), hydrogen cyanide (HCN) molecular and [CII] atomic emission lines in blind redshift surveys in the submillimeter-centimeter spectral regime. Our model uses: (a) recently available HCN Spectral Line Energy Distributions (SLEDs) of local Luminous Infrared Galaxies (LIRGs, L_IR>10^11 L_sun), (b) a value for epsilon=SFR/M_dense(H_2) provided by new developments in the study of star formation feedback on the interstellar medium and (c) a model for the evolution of the infrared luminosity density. Minimal 'emergent' CO SLEDs from the dense gas reservoirs expected in all star-forming systems in the Universe are then computed from the HCN SLEDs since warm, HCN-bright gas will necessarily be CO-bright, with the dense star-forming gas phase setting an obvious minimum to the total molecular gas mass of any star-forming galaxy. We include [CII] as the most important of the far-infrared cooling lines. Optimal blind surveys with the Atacama Large Millimeter Array (ALMA) could potentially detect very distant (z~10-12) [CII] emitters in the >ULIRG galaxy class at a rate of ~0.1-1 per hour (although this prediction is strongly dependent on the star formation and enrichment history at this early epoch), whereas the (high-frequency) Square Kilometer Array (SKA) will be capable of blindly detecting z>3 low-J CO emitters at a rate of ~40-70 per hour. The [CII] line holds special promise for the detection of metal-poor systems with extensive reservoirs of CO-dark molecular gas where detection rates with ALMA can reach up to 2-7 per hour in Bands 4-6.}, added-at = {2012-06-22T17:32:15.000+0200}, author = {Geach, James E. and Papadopoulos, Padelis P.}, biburl = {https://www.bibsonomy.org/bibtex/27052c9fe8170446ea0d0fe4dc80794df/miki}, description = {[1206.4693] Molecular and atomic line surveys of galaxies I: the dense, star-forming phase as a beacon}, interhash = {7dc3268bcd8916b0fea0ad8739c676b4}, intrahash = {7052c9fe8170446ea0d0fe4dc80794df}, keywords = {alma emission line survey}, note = {cite arxiv:1206.4693Comment: 16 pages, 9 figures, accepted for publication in ApJ}, timestamp = {2012-06-22T17:32:15.000+0200}, title = {Molecular and atomic line surveys of galaxies I: the dense, star-forming phase as a beacon}, url = {http://arxiv.org/abs/1206.4693}, year = 2012 }