The conformity of H I galaxies in ALFALFA-SDSS sample

• 作者: Lin-Cheng Li Bo Qin Jie Wang Jing Wang You-Gang Wang
• 来源期刊: 天文和天体物理学研究
• 年，卷（期）: 2021,（2）
• 页码范围: 61-67
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-4527/21/2/32

摘要

The conformity effect,indicating the evolution of galaxies is related to its surrounding neighbor galaxies as far as a few Mpc,is an interesting phenomenon in the modeling of galaxy and evolution.Here we study the conformity effect of HI galaxies in a matched galaxy sample between SDSS DR7 and ALFALFA surveys.By checking the probability difference for the detected HI galaxies as a function of distance around a normal or an H I galaxy,we find that this effect is significant out to 5 Mpc.It also shows a dependence on the stellar mass of galaxies,with the strength the strongest in the stellar mass range of 1010＜M*/M⊙＜1010.5.However,when the sample is confined to central galaxies in groups with virial radii smaller than 1 Mpc,the 1-halo conformity signal is still evident,while the 2-halo conformity signal is reduced to a very weak amplitude.Our results confirm the previous study in the optical band that the 2-halo term is possibly caused by the bias effect in the sample selection.Furthermore,we confirm the existence of the 1-halo conformity discovered in the optical and radio band in previous investigations.Our results provide another viewpoint on the conformity effect and hope to shed light on the co-evolution of the galaxies and their neighbors in the current galaxy formation models.