@article{oai:jaxa.repo.nii.ac.jp:00036659,
 author = {SHIBAI, Hiroshi},
 journal = {The Institute of Space and Astronautical Science report. S.P. : Mid- and Far-Infrared Astronomy and Future Space Mission},
 month = {Dec},
 note = {The observability of Hydrogen molecules in absorption is investigated. For solarabundances, such as in the Galaxy, the absorption measurement is very difficult because the ab-sorption efficiency of the Hydrogen molecular absorption lines is significantly smaller than that ofdust grains. On the other hand, in the metal-poor condition as expected in the early Universe,the absorption efficiency of the Hydrogen molecules become comparable with or larger than thatof the dust grains. If we could use bright infrared sources behind the molecular gas clouds, theabsorption measurement of the Hydrogen molecules would be an important technique to analyzethe primordial gas clouds that are contracting into first-generation objects. The SPICA (SpaceInfrared Telescope for Cosmology and Astrophysics) will be sensitive enough to detect a moleculargas could of 1024 cm-2 against an infrared source of 10 mJy flux. These observations would beable to reveal the distribution of the primordial molecular gas clouds in the early Universe., 資料番号: SA4586769000},
 pages = {67--74},
 title = {Absorption Measurement of Hydrogen Molecules in the Early Universe},
 volume = {14},
 year = {2000}
}