Evolution and formation of galaxies seen through an ISO Far-infrared survey

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We have carried out a deep far-infrared survey at 95 & 175 μm using ISOPHOT onboard ISO (Infrared Space Observatory) that was put in operation in 1995 This ISO far-infrared survey has detected 100 time more sources than expected from the no-evolution model. It is very important to make optical identification and to measure the redshift of these object by performing follow-up observations from the ground. This project intended to do :1 performing the accurate analysis of the ISO far-infrared survey, generating a highly reliable catalog of ISO far-infrared sources to give a firm base for follow-up observations, and comparing the number density of these sources with the models of galaxies for obtaining information on formation and evolution of galaxies ;2 executing follow-up observations from the optical to radio and measuring basic quantities such as redshift ;3 building a CCD imaging system and carrying out CCD imaging over the fields of European Large Area ISO Survey.We have achieved t … More he following :1 We have performed data analysis with sufficient accuracy of the ISO far-infrared survey based on the most recent calibration for ISO data, and successfully generated a reliable catalog of far-infrared sources. We have obtained number-flux relations using this catalog, and examined the completeness of the survey through simulation Comparing the relations with the models of far-infrared source counts, we found that (1) the star formation rate (SFR) around z 〜0.4 was 100 times higher than the present day SFR, and (2) SFR at high redshift should have been lower than SFR at z 〜0.4 due to the constraint from the Infrared Cosmic Background Radiation.2 We have carried out spectroscopy on the 1.8m telescope at the Okayama Observatory, 20cm imaging using VLA (Very Long Array in USA), and millimeter/submillimeter observations using the 45m telescope at the Nobeyama Observatory, IRAM 30m telescope at Spain, and CSO 10m telescope at Hawaii. The VLA observations were executed very successfully, providing the accurate coordinates of far-infrared sources for the first time. This is indeed a milestone of follow-up observations. Spectroscopy with the KECK telescope is scheduled in March this year.3 The CCD imaging system has almost been completed, and this will be installed on the UK Schmidt telescope at AAO in Australia. This will be commissioned in April in 2000. Less