Scalar clouds around Kerr–Sen black holes

Yang Huang, Dao-Jun Liu, Xiang-Hua Zhai, Xin-Zhou Li
2017 Classical and quantum gravity  
In this paper, the behaviour of a charged massive scalar test field in the background of a Kerr-Sen black hole is investigated. A kind of stationary solutions, dubbed scalar clouds, are obtained numerically and expressed by the existence lines in the parameter space. We show that for fixed background and a given set of harmonic indices, the mass and charge of the scalar clouds are limited in a finite region in the parameter space of the scalar field. Particularly, the maximum values of the mass
more » ... and charge of the clouds around extremal Kerr-Sen black holes are independent of the angular velocity of the black hole, whereas those in the extremal Kerr-Newman background depend on the angular velocity. In addition, it is demonstrated that, as the static limit of Kerr-Sen black hole, Gibbons-Maeda-Garfinkle-Horowitz-Strominger black hole can not support scalar cloud.
doi:10.1088/1361-6382/aa7964 fatcat:zyxoln373vdftb5nbrqh5dtoxi