首页|Close Major-merger Pairs at z=0:Star-forming Galaxies with Pseudobulges

Close Major-merger Pairs at z=0:Star-forming Galaxies with Pseudobulges

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
We present a study of star-forming galaxies(SFGs)with pseudobulges(bulges with Sérsic index n＜2)in a local close major-merger galaxy pair sample(H-KPAIR).With data from new aperture photometries in the optical and near-infrared bands(aperture size of 7 kpc)and from the literature,we find that the mean Age of central stellar populations in Spirals with pseudobulges is consistent with that of disky galaxies and is nearly constant against the bulge-to-total ratio(B/T).Paired Spirals have a slightly lower fraction of pure disk galaxies(B/T ≤ 0.1)than their counterparts in the control sample.Compared to SFGs with classical bulges,those with pseudobulges have a higher(＞2σ)mean of specific star formation rate(sSFR)enhancement(sSFRenh=0.33±0.07 versus sSFRenh＝ 0.12±0.06)and broader scatter(by～1dex).The eight SFGs that have the highest sSFRenh in the sample all have pseudobulges.A majority(69％)of paired SFGs with strong enhancement(having sSFR more than 5 times the median of the control galaxies)have pseudobulges.The Spitzer data show that the pseudobulges in these galaxies are tightly linked to nuclear/circum-nuclear starbursts.Pseudobulge SFGs in S+S and in S+E pairs have significantly(＞3σ)different sSFR enhancement,with the means of sSFRenh=0.45±0.08 and-0.04±0.11,respectively.We find a decrease in the sSFR enhancements with the density of the environment for SFGs with pseudobulges.Since a high fraction(5/11)of pseudobulge SFGs in S+E pairs are in rich groups/clusters(local density N1Mpc ≥ 7),the dense environment might be the cause for their low sSFRenh.

galaxies:evolutiongalaxies:interactionsgalaxies:star formationgalaxies:structuregalaxies:bulgesgalaxies:photometry

何川、徐聪、Ute Lisenfeld、戴昱、方陶陶、黄家声、王炜、余清正

展开 >

Chinese Academy of Sciences South America Center for Astronomy,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China

School of Astronomy and Space Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

Departamento de Física Teórica y del Cosmos,Universidad de Granada,18071 Granada,Spain

Instituto Carlos Ⅰ de Física Téorica y Computacional,Facultad de Ciencias,18071 Granada,Spain

Department of Astronomy,Xiamen University,Xiamen 361005,China

CAS Key Laboratory of Optical Astronomy,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China

展开 >

National Natural Science Foundation of China(NSFC)National Natural Science Foundation of China(NSFC)Junta de Andaluciaía(Spain)grantNational Key R&D Program of ChinaNational Natural Science Foundation of China(NSFC)National Natural Science Foundation of China(NSFC)National Natural Science Foundation of China(NSFC)China Manned Space Project

1187305511933003FQM1082017YFA0402600118906921213300812221003CMS-CSST-2021-A04

2024

10.1088/1674-4527/ad392c

天文和天体物理学研究
中国科学院国家天文台

天文和天体物理学研究

CSTPCD
影响因子：0.406
ISSN：1674-4527
年,卷(期)：2024.24(5)
  • 67