arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0908.2435gr-qcastro-ph.GA
收藏

多态玻色子星

Multi-state Boson Stars

Argelia Bernal, Juan Barranco, Daniela Alic, Carlos Palenzuela

摘要:

由于人们对考虑标量场作为暗物质候选者的模型越来越感兴趣,我们构造了一个广义的相对论玻色子星(BS),它由标量场的基态和第一激发态两个共存态组成.我们利用数值方法研究了这些多态玻色子星在径向扰动下的动力学演化。当第一激发态中的粒子数N2小于基态中的粒子数N1时,可以构造稳定的MSBS。另一方面,当N2 > N1时,构型初始不稳定。然而,它们会进化并稳定下来,形成稳定的构型。在稳定化过程中,初始基态被激发并以第一激发态结束,而初始第一激发态以基态结束。在这个过程中,两种状态都发射出标量场辐射,减少了它们的粒子数。这种行为表明,即使在第一激发态的BS在有限扰动下本质上是不稳定的,从该状态与基态的组合产生的配置产生稳定的对象。最后,我们表明,在一个定性的方式,稳定的MSBS可能是现实的模型的暗物质星系晕,因为它们产生的旋转曲线是平坦的,在大半径比旋转曲线BS只有一个状态。

英文摘要:

Motivated by the increasing interest in models which consider scalar fields as viable dark matter candidates, we have constructed a generalization of relativistic Boson Stars (BS) composed of two coexisting states of the scalar field, the ground state and the first excited state. We have studied the dynamical evolution of these Multi-state Boson Stars (MSBS) under radial perturbations, using numerical techniques. We show that stable MSBS can be constructed, when the number of particles in the first excited state, N2, is smaller than the number of particles in the ground state, N1. On the other hand, when N2 > N1, the configurations are initially unstable. However, they evolve and settle down into stable configurations. In the stabilization process, the initially ground state is excited and ends in a first excited state, whereas the initially first excited state ends in a ground state. During this process, both states emit scalar field radiation, decreasing their number of particles. This behavior shows that even though BS in the first excited state are intrinsically unstable under finite perturbations, the configuration resulting from the combination of this state with the ground state produces stable objects. Finally we show in a qualitative way, that stable MSBS could be realistic models of dark matter galactic halos, as they produce rotation curves that are flatter at large radii than the rotation curves produced by BS with only one state.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑