Local galaxies with compact cores as the possible descendants of massive compact quiescent galaxies at high redshift  

作　　者：Ying Gao Lu-Lu Fan 高颖;范璐璐(Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment,School of Space Science and Physics,Institute of Space Sciences,Shandong University,Weihai 264209,China; CAS Key Laboratory for Research in Galaxies and Cosmology,Department of Astronomy,University of Science and Technology of China,Hefei 230026,China; School of Astronomy and Space Sciences,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment,School of Space Science and Physics,Institute of Space Sciences,Shandong University,Weihai 264209,China [2]CAS Key Laboratory for Research in Galaxies and Cosmology,Department of Astronomy,University of Science and Technology of China,Hefei 230026,China [3]School of Astronomy and Space Sciences,University of Science and Technology of China,Hefei 230026,China

出　　处：《Research in Astronomy and Astrophysics》2020年第7期139-148,共10页天文和天体物理学研究（英文版）

基　　金：supported by National Key R&D Program of China (No.2017YFA0402703);support from the National Natural Science Foundation of China (NSFC;Grant Nos.11822303;11773020 and 11421303);Shandong Provincial Natural Science Foundation,China(ZR2017QA001 and JQ201801);Funding for the SDSS and SDSS-II has been provided by the Alfred P.Sloan Foundation;the Participating Institutions,the National Science Foundation;the U.S.Department of Energy;the National Aeronautics and Space Administration;the Japanese Monbukagakusho;the Max Planck Society;the Higher Education Funding Council for England。

摘　　要：In order to test a possible evolutionary scenario of high-z compact quiescent galaxies(cQGs)that they can survive as local compact cores embedded in local massive galaxies with different morphology classes, we explore the star formation histories of local compact cores according to their spectral analysis.We build a sample of 182 massive galaxies with compact cores(M*,core> 10^10.6 M⊙) at 0.02 ≤ z ≤ 0.06 from SDSS DR7 spectroscopic catalogue. The STARLIGHT package is used to analyze the median stacked spectra and derive the stellar ages and metallicities. Our main results show that local compact cores have the average age of about 12.1 ± 0.6 Gyr, indicating their early formation at z > 3, which is consistent with the formation redshifts of cQGs at 1 < z < 3. Together with previous studies, our result that local compact cores have similar formation redshifts as those of high-z cQGs, supports that local massive galaxies with compact cores are possible descendants of cQGs. Morphological study of local galaxies with compact cores suggests that there would be multiple possible evolutionary paths for high-z cQGs: most of them(> 80%)will evolve into local massive early-type galaxies according to dry minor merger, while some of them(~ 15%) will build substantial stellar/gas discs according to the late-time gas accretion and sustaining star formation, and finally grow up into spiral galaxies.

关 键 词：galaxies:bulges galaxies:evolution galaxies:formation galaxies:stellar content galaxies:structure 

分 类 号：P157[天文地球—天文学]