Related papers: Can eccentric binary millisecond pulsars form by a…
We report the discovery and characterization of PSR J1810-0623, a fully recycled millisecond pulsar with a spin period of 4.55 ms, discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) and followed up with FAST…
The gigaelectronvolt $\gamma$-ray excess observed towards the Galactic centre remains unexplained. While dark matter annihilation has long been considered a leading explanation, an alternative scenario involving a large population of…
We sketch a possible evolutionary scenario by which a highly magnetized super-Chandrasekhar white dwarf could be formed by accretion on to a commonly observed magnetized white dwarf. This is an exploratory study, when the physics in…
We present a new dynamical scenario for the formation of short-period binary millisecond pulsars in globular clusters. Our work is motivated by the recent observations of 20 radio pulsars in 47 Tuc. In a dense cluster such as 47 Tuc, most…
Close-orbit low-mass X-ray binaries (LMXBs), radio binary millisecond pulsars (BMSPs) with extremely low-mass helium WDs (ELM He~WDs) and ultra-compact X-ray binaries (UCXBs) are all part of the same evolutionary sequence. It is therefore…
High sensitivity searches of globular clusters (GC) for radio pulsars by improved pulsar search algorithms and sustained pulsar timing observations have so far yielded some 140 pulsars in more than two dozen GCs. The observed distribution…
We summarize the channels formation of neutron stars (NS) in single or binary evolution and the classic recycling scenario by which mass accretion by a donor companion accelerates old NS to millisecond pulsars (MSP). We consider the…
A millisecond pulsar is a neutron star that has been substantially spun up by accretion from a binary companion. A previously unrecognized factor governing the spin evolution of such pulsars is the crucial effect of non-steady or transient…
The accretion-induced collapse (AIC) of a rotating white dwarf (WD) offers a potential site of millisecond pulsars/magnetars, gamma-ray bursts, and r-process nucleosynthesis. We present three-dimensional general-relativistic…
One channel to form millisecond pulsars with CO white dwarf companions is through the stable Roche-lobe overflow of intermediate-mass ($3\,{\rm M}_\odot\lesssim M\lesssim 5\,{\rm M}_\odot$) stars at the end of the main sequence (Case A) or…
The accretion-induced collapse (AIC) of a white dwarf to form a neutron star can leave behind a rotationally supported disk with mass of up to ~ 0.1 M_sun. The disk is initially composed of free nucleons but as it accretes and spreads to…
Low-mass white dwarfs can either be produced in low-mass X-ray binaries by stable mass transfer to a neutron star, or in a common-envelope phase with a heavier white dwarf companion. We have searched 8 low-mass white dwarf candidates…
We present the first seconds-long 2D general relativistic neutrino magnetohydrodynamic simulations of accretion-induced collapse (AIC) in rapidly rotating, strongly magnetized white dwarfs (WDs), which might originate as remnants of…
To track the formation and evolution links of the millisecond pulsars (MSPs) powered by accretion and rotation in the Galactic field, we investigate the spin period (P) and spin-down power (Edot) distributions of the MSPs observed at the…
Early B-type main-sequence (MS) stars (M$_1$ = 5-16 M$_{\odot}$) with closely orbiting low-mass stellar companions (q = M$_2$/M$_1$ < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However,…
It is generally believed that Ultracompact X-ray binaries (UCXBs) evolved from binaries consisting of a neutron star accreting from a low-mass white dwarf or helium star where mass transfer is driven by gravitational radiation. However, the…
A model for the formation and evolution of binary millisecond radio pulsars in systems with low mass companions (< 0.1 Msun) is investigated using a binary population synthesis technique. Taking into account the non conservative evolution…
White dwarf stars are the most common stellar fossils. When in binaries, they make up the dominant form of compact object binary within the Galaxy and can offer insight into different aspects of binary formation and evolution. One of the…
Six of the eight double neutron stars known in the Galactic disk have low orbital eccentricities (< 0.27) indicating that their second-born neutron stars received only very small velocity kicks at birth. This is similar to the case of the…
Millisecond pulsars, old neutron stars spun-up by accreting matter from a companion star, can reach high rotation rates of hundreds of revolutions per second. Until now, all such "recycled" rotation-powered pulsars have been detected by…