Evolution of the high-density cores in molecular clouds: Part 2

scientific abstract recent highresolution radio mapping observations have revealed the presence of the highdensity cores in molecular clouds. these are the most likely places for starformation. in fact, iras has found a good correlation between the farinfrared point sources and the cores. the iras sources associated with the cores (class i sources) are believed to be in a very early stage of starformation, i.e., candidate protostars. these are considered to evolve to lowmass mainsequence stars via t tauri phases. however, not all of the radio cores are associated with the iras sources and the nature of the cores without the iras sources are not well known. one explanation is that the core source is still too cold to be detected by iras. if the sensitivity is high enough, even such cold sources will be detected and we can distinguish between the cold cores without any farinfrared sources and the cold cores with faint farinfrared sources. if detected, the faint farinfrared sources are likely to be the precursor of class i sources. another explanation is that the cores without iras sources are actually in a stage before forming stars. we propose to make deep farinfrared survey of the radioselected sample of highdensity molecular cores in taurus or ophiuchus depending on the launch season. the targets are selected based on the nobeyama radio observatory c18o maps and univ. nagoya surveys. observation summary photometry and imaging of the compact continuum emission in 103 highdensity cores either in the taurus or ophiuchus dark clouds (comprising of 90 sources detected with the nro 45m telescope and 13 sources selected by the nagoya group) will be made with phtc in 3 filters (60, 100, and 180 microns), and with phtp in 2 filters (11.5 and 25 microns) using an aperture of 52 arcsec. the large aperture for phtp is used for matching the pixels scale of phtc. th truncated!, Pleas [truncated!, Please see actual data for full text]