Unbiased large spectroscopic surveys of galaxies selected by SPICA using dust bands

摘要: The mid-infrared (IR) range contains many spectral features associated with large molecules and dust grains such as polycyclic aromatic hydrocarbons (PAHs) silicates. These are usually very strong compared to fine-structure gas lines, thus valuable in studying the properties of faint distant galaxies. In this paper, we evaluate capability low-resolution mid-IR spectroscopic surveys galaxies that could be performed by SPICA. designed address question how star formation black hole accretion activities evolved over cosmic time through diagnostics physical conditions interstellar/circumnuclear media On basis results obtained Herschel far-IR photometric Spitzer AKARI near- observations nearby galaxies, estimate numbers at redshift z > 0.5, which expected detected PAH or continuum a wide (10 deg^2) deep (1 blind survey, both for given observation 600 hours. As by-products also expect detect debris disks, excess above photospheric emission main-sequence stars, their number. We demonstrate SPICA will efficiently provide us unprecedentedly samples, can studied further