H2 Absorption Measurement of Primordial Clouds

H. Shibai; T. T. Takeuchi; T. N. Rengarajan; H. Hirashita

doi:10.1051/eas:2002106

All issues

Volume 4 (2002)

EAS Publications Series, 4 (2002) 387

Abstract

Issue		EAS Publications Series Volume 4, 2002 Infrared and Submillimeter Space Astronomy: An International Colloquium to Honor the Memory of Guy Serra


Page(s)		387 - 387
Section		Posters
DOI		https://doi.org/10.1051/eas:2002106
Published online		25 September 2002

Infrared and Submillimeter Space Astronomy: An International Colloquium to Honor the Memory of Guy Serra
M. Giard, J.P. Bernard, A. Klotz and I. Ristorcelli (eds)
EAS Publications Series, 4 (2002) 387

H₂ Absorption Measurement of Primordial Clouds

H. Shibai¹, T. T. Takeuchi², T. N. Rengarajan³ and H. Hirashita⁴

¹ Nagoya University, Nagoya, Japan
² National Astronomical Observatory, Mitaka, Tokyo, Japan
³ Instituto Nacional de Astrofisica Optica y Electronica, Tonantzintla, Mexico
⁴ Osservatorio Astrofisico di Arcetri, Firenze, Italy

Corresponding author: shibai@phys.nagoya-u.ac.jp

Abstract

The observability of hydrogen molecules in absorption was investigated for infrared lines against bright infrared sources. The absorption efficiency of the hydrogen molecules becomes comparable with or larger than that of the dust grains in the metal-poor condition expected in the early Universe. If we can use bright infrared continuum sources behind the molecular gas clouds, the absorption measurement of the hydrogen molecules will be an important technique to explore the primordial gas clouds that are contracting into first-generation objects.