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تسجيل مستخدم جديدUltraluminous Infrared Galaxies in the AKARI All Sky Survey
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We present a new catalog of 118 Ultraluminous Infrared Galaxies (ULIRGs) and one Hyperluminous Infrared Galaxy (HLIRG) by crossmatching AKARI all-sky survey with the Sloan Digital Sky Survey Data Release 10 (SDSS DR10) and the Final Data Release of the Two-Degree Field Galaxy Redshift Survey (2dFGRS). 40 of the ULIRGs and one HLIRG are new identifications. We find that ULIRGs are interacting pair galaxies or ongoing/post mergers. This is consistent with the widely accepted view: ULIRGs are major mergers of disk galaxies. We confirm the previously known positive trend between the AGN fraction and IR luminosity. We show that ULIRGs have a large off-set from the main sequence up to z~1; their off-set from the z~2 main sequence is relatively smaller. We find a consistent result with the previous studies showing that compared to local star forming SDSS galaxies of similar mass, local ULIRGs have lower oxygen abundances. We for the first time demonstrate that ULIRGs follow the fundamental metallicity relation (FMR). The scatter of ULIRGs around the FMR (0.09 dex - 0.5 dex) is comparable with the scatter of z~2-3 galaxies. Their optical colors show that ULIRGs are mostly blue galaxies and this agrees with previous findings. We provide the largest local (0.050 < z < 0.487) ULIRG catalog with stellar masses, SFRs, gas metallicities and optical colors. Our catalog provides us active galaxies analogous to high-z galaxies in the local Universe where they can be rigorously scrutinized.
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