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Redbacks (RBs) and black widows (BWs) are two peculiar classes of eclipsing millisecond pulsars (MSPs). The accretion-induced collapse (AIC) of an oxygen/neon/magnesium composition white dwarf to a neutron star has been suggested as one possible formation pathway for those two classes of MSPs. However, it is difficult to produce all known MSPs with the traditional AIC scenario. In this study by using the MESA stellar evolution code, we investigate the detailed pre-AIC evolution of magnetized white dwarf binaries with the magnetic confinement model where the high magnetic field strength of the white dwarf can confine the accreted matter in the polar caps. We find that the initial donor mass and orbital periods in our model can be lower than that of previous traditional AIC models. We also present post-AIC evolution models to form RBs and BWs with and without the spin down luminosity evaporation of MSPs. Under the magnetic confinement model and evaporative winds (with corresponding angular momentum loss from the surface of the donor star), the companion masses and orbital periods of all known RBs can be covered and a number of binaries can evolve to become BWs.
The wealth of detections of millisecond pulsars (MSPs) in $gamma$-rays by {em Fermi} has spurred searches for these objects among the several unidentified $gamma$-ray sources. Interesting targets are a sub-class of binary MSPs, dubbed Black Widows (B
Millisecond pulsars (MSPs) are generally believed to be old neutron stars (NSs), formed via type Ib/c core-collapse supernovae (SNe), which have been spun up to high rotation rates via accretion from a companion star in a low-mass X-ray binary (LMXB)
Black widows and redbacks are binary systems consisting of a millisecond pulsar in a close binary with a companion having matter driven off of its surface by the pulsar wind. X-rays due to an intra-binary shock have been observed from many of these s
Gamma-ray data from the Fermi-Large Area Telescope reveal an unexplained, apparently diffuse, signal from the Galactic bulge. The origin of this Galactic Center Excess (GCE) has been debated with proposed sources prominently including self-annihilati
Black widow and redback systems are compact binaries in which a millisecond pulsar heats and may even ablate its low-mass companion by its intense wind of relativistic particles and radiation. In such systems, an intrabinary shock can form as a site