Computer Science – Performance
Scientific paper
May 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011iaus..280p.242l&link_type=abstract
The Molecular Universe, Posters from the proceedings of the 280th Symposium of the International Astronomical Union held in Tole
Computer Science
Performance
Scientific paper
Recent theoretical and observational studies show that most of the extremely bright submillimeter galaxies (SMGs) at wavelengths larger than 500 μm are lensed by foreground objects. By targeting lensed objects, we can study the typical properties of the star forming galaxies in the early Universe that would otherwise be inaccessible in a blank survey due to sensitivity limitations and source confusion. With current instruments capable of measuring multiple CO lines, such as CSO/APEX/Z-Spec, GBT/Zpectrometer and IRAM/PdBI, it is possible to determine the redshifts of the brightest sources found in the ongoing large area surveys, namely H-ATLAS, HerMES, and the SPT survey. These measurements will be soon surpassed by the greater sensitivities and bandwidth coverage of the upcoming facilities, such as ALMA, CCAT, and SPICA. The physical properties of the molecular gas in these SMGs can be initially constrained using 12CO lines, but this method is often limited by the unknown source sizes, and suffers from strong degeneracies. Multiple CO lines, the 12CO (1-0) line in particular, are essential in breaking the density/temperature degeneracy and distinguishing between multiple gas components. To complete the picture of the SMG ISM, and to make a direct comparison with local galaxies, we investigate the diagnostic power of water and high density gas tracers, such as such as HCN, HNC, HCO+, and 13CO. Strong water lines have been detected in Mrk231 and tentatively identified by Z-Spec in the Cloverleaf quasar and in the H-ATLAS source SDP.17b, the latter recently confirmed with IRAM/PdBI. Dense gas tracer lines can be more than 20 times weaker than the 12CO lines, and their detection in lensed galaxies will take full advantage of the ALMA capabilities. It is therefore essential to define the most efficient set of lines that will reveal the physical properties of the ISM and its excitation mechanisms. Combining available atomic line diagnostics and measurements of the dense gas tracers in local galaxies, we can test the performance of new molecular indicators of AGN activity and star formation in both high- and low- redshift galaxies. This set of diagnostic tools and corresponding measurements on a sample of SMGs will enable us to outline the requirements for the future instruments and the surveys to be undertaken by CCAT and SPICA.
Lupu Roxana
Z-Spec Team
No associations
LandOfFree
Investigating the molecular content of lensed submillimeter galaxies 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 Investigating the molecular content of lensed submillimeter galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Investigating the molecular content of lensed submillimeter galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-929962