Abstract

A model of a population of ultraluminous X-ray sources with magnetized neutron stars (NULXs) in a spiral galaxy with a star formation history as in the thin disk of the Milky Way is constructed by the hybrid population synthesis method. First, based on analytical approximations (BSE code), we compute a set of close binary systems (CBSs), potential precursors of NULXs, and, then, the evolution with mass accretion onto magnetized neutron stars (NSs) is computed by the MESA evolutionary code. The accretion rate onto NSs and the X-ray luminosity of sources are calculated for the models of sub- or supercritical disks and disks with advection. During accretion onto magnetized NSs, super-Eddington luminosities \(L_{\textrm{X}}>10^{38}\) erg s\({}^{-1}\) are reached already at the subcritical stage, when the energy release at the inner boundary of the disk defined by the NS magnetosphere is sub-Eddington one. Our calculations show that the standard evolution of CBSs, given the peculiarities of accretion onto magnetized NSs, allows the observed properties of NULXs (X-ray luminosities, NS spin periods, CBS orbital periods, and optical component masses) to be quantitatively explained without requiring additional model assumptions about the collimation of X-ray emission from NSs with a high observed super-Eddington luminosity. In a model galaxy with a star formation rate \({\sim}5M_{\odot}\) yr\({}^{-1}\) there can be several NULXs. The detection of a powerful wind from NULXs with \(L_{\textrm{X}}\sim 10^{41}\) erg s\({}^{-1}\) may suggest supercritical accretion onto magnetized NSs.

中文翻译：

---

磁化中子星的超发光X射线源的种群合成

摘要

通过混合种群合成方法，建立了具有银河系薄盘中具有恒星形成历史的旋涡星系中具有磁化中子星（NULXs）的超发光X射线源的种群模型。首先，基于解析近似（BSE代码），我们计算出一组近似的二元系统（CBS），NULX的潜在前体，然后，由MESA进化算法计算出在磁中子星（NSs）上质量累积的演化。码。对于亚临界或超临界磁盘和具有平流的磁盘模型，计算了它们在NS上的吸积率和X射线源的光度。在磁化NSs上积聚期间，超爱丁顿光度\（L _ {\ textrm {X}}> 10 ^ {38} \） erg s \（{} ^ {-1} \）当由NS磁层限定的盘内边界的能量释放为亚爱丁顿一级时，在亚临界阶段就已经达到了α。我们的计算表明，考虑到磁化NS上积聚的特殊性，CBS的标准演变可以定量地说明所观察到的NULX的特性（X射线光度，NS自旋周期，CBS轨道周期和光学组件质量）关于具有较高观测到的超爱丁顿光度的NSs的X射线准直的其他模型假设。在具有恒星形成速率\（{\ sim} 5M _ {\ odot} \） yr \（{} ^ {-1} \）的模型星系中，可以有多个NULX。使用\（L _ {\ textrm {X}} \ sim 10 ^ {41} \）从NULX中检测到强风erg s \（{} ^ {-1} \）可能暗示在磁化NS上超临界积聚。