Observational studies of galaxies in the era of violent evolution

2014 Fiscal Year Final Research Report

• Project/Area Number: 24540230
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: Kyoto University
• Principal Investigator: OHTA Kouji 京都大学, 理学(系)研究科(研究院), 教授 (50221825)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 銀河 / 電波天文学 / 光赤外線天文学

Outline of Final Research Achievements

Studies of evolution of galaxies at redshift = 1~2 (cosmic age of 3-5 Gyr) are important, because galaxies are considered to be evolving violently in the era.
We estimated molecular gas masses and the fractions for star-forming galaxies in the universe with an age of about 4 Gyr with ALMA telescope. We also derived gas metallicity in galaxies in the same era by using the Subaru telescope. Comparing these quantities with galaxy chemical evolution model, we found that gas inflow and out flow into/from galaxies play an important role for galaxy evolution; galaxies have been evolving by blancing gas inflow and star formation and gas out flow. We also studied evolution of galaxy morphology; the epoch of emergence of round disk galaxies is turned out to be around at the cosmic age of 6 Gyr.

Free Research Field

天文学