We calculate the evolution of close binary systems (CBSs) formed by a neutron star (behaving as a radio pulsar) and a normal donor star, evolving either to helium white dwarf (HeWD) or ultra short orbital period systems. We consider X-ray irradiation feedback and evaporation due to radio pulsar irradiation. We show that irradiation feedback leads to cyclic mass transfer episodes, allowing CBSs to be observed in-between as binary radio pulsars under conditions in which standard, non-irradiated models predict the occurrence of a low mass X-ray binary. This behavior accounts for the existence of a family of eclipsing binary systems known as redbacks. We predict that redback companions should almost fill their Roche lobe, as observed in PSR J1723-2837. This state is also possible for systems evolving with larger orbital periods. Therefore, binary radio pulsars with companion star masses usually interpreted as larger than expected to produce HeWDs may also result in such {\it quasi - Roche Lobe Overflow} states, rather than hosting a carbon-oxygen WD.
We found that CBSs with initial orbital periods $\mathrm{P_{i}<1}$ day evolve into redbacks. Some of them produce low mass HeWDs, and a subgroup with shorter $\mathrm{P_{i}}$ become black widows (BWs). Thus, BWs descent from redbacks, although not all redbacks evolve into BWs.
There is mounting observational evidence favoring that BW pulsars are very massive ($\mathrm{\gtrsim 2\; M_{\odot}}$). As they should be redback descendants, redback pulsars should also be very massive, since most of the mass is transferred before this stage.
Do all millisecond pulsars share a common heritage?
低质量X射线双星系统中中子星毫秒脉动的发现证实了毫秒射电双星与低质量X射线双星系统之间的联系。从那时起，从LMXB产生毫秒射电双星，然后由于偶极辐射而自旋下降的过程被认为是毫秒射电双星的“标准进化”。然而，是否所有观测到的毫秒射电暴都可以由LMXB产生的问题直到现在还没有得到定量的解决。标准的演化过程产生的毫秒周期（P）和自旋下降速率（Pdot）并不完全独立。毫秒级射电望远镜可能达到的P-Pdot值受到联合约束。为了检验观测到的毫秒射电天体是否是毫秒X射线天体（MSXP）的明确后代，我们制作了一张概率图，它代表了标准模型下毫秒射电天体的预期分布。我们以超过95%的置信度表明，在标准模型的框架内，所观测到的毫秒X射线天体不能产生具有高磁场的最快旋转毫秒射电天体，例如PSR B 1937 +21。
