Searching for a possible dipole anisotropy in acceleration scale with 147 rotationally supported galaxies  

作　　者：Zhe Chang Hai-Nan Lin Zhi-Chao Zhao Yong Zhou 常哲;林海南;赵志超;周勇(Institute of High Energy Physics, Chinese Academy of Sciences;School of Physical Sciences, University of Chinese Academy of Sciences;Department of Physics, Chongqing University)

机构地区：[1]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [2]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [3]Department of Physics,Chongqing University,Chongqing 401331,China

出　　处：《Chinese Physics C》2018年第11期137-144,共8页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China(11675182,11690022,11603005)

摘　　要：We report a possible dipole anisotropy in acceleration scale g↑ with 147 rotationally supported galaxies in the local Universe. It is found that a monopole and dipole correction for the radial acceleration relation can better describe the SPARC data set. The monopole term is negligible but the dipole magnitude is significant. It is also found that the dipole correction is mostly induced by anisotropy in the acceleration scale. The magnitude of the g↑-dipole reaches 0.25±0.04, and its direction is aligned to （l,b）=（171.30°±7.18°,-15.41°±4.87°）, which is very close to the maximum anisotropy direction from the hemisphere comparison method. Furthermore, a robust check shows that the dipole anisotropy could not be reproduced by an isotropic mock data set. However, it is still premature to claim that the Universe is anisotropic, due to the small data samples and uncertainty in the current observations.We report a possible dipole anisotropy in acceleration scale g↑ with 147 rotationally supported galaxies in the local Universe. It is found that a monopole and dipole correction for the radial acceleration relation can better describe the SPARC data set. The monopole term is negligible but the dipole magnitude is significant. It is also found that the dipole correction is mostly induced by anisotropy in the acceleration scale. The magnitude of the g↑-dipole reaches 0.25±0.04, and its direction is aligned to （l,b）=（171.30°±7.18°,-15.41°±4.87°）, which is very close to the maximum anisotropy direction from the hemisphere comparison method. Furthermore, a robust check shows that the dipole anisotropy could not be reproduced by an isotropic mock data set. However, it is still premature to claim that the Universe is anisotropic, due to the small data samples and uncertainty in the current observations.

关 键 词：GALAXIES kinematics and dynamics GALAXIES fundamental parameters large-scale structure of Universe 

分 类 号：P159[天文地球—天文学]