Search Results - "Neutron stars."

Based on well-grounded Galactic neutron star populations formed from radio pulsar population syntheses of canonical pulsars (CPs) and millisecond pulsars (MSPs), we use the latest Fermi Large Area Telescope catalog (4FGL-DR4) to investigate the implications of proposed γ -ray luminosity models. Usin...

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We conducted a timing analysis of PSR J0922+0638 (B0919+06) using data from the Nanshan 26 m radio telescope and the MeerKAT telescope, spanning from 2001 January to 2023 March. During this 22 yr period, we discovered a previously unreported small glitch (glitch 1) before the well-known large glitch...

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We propose a possible binary evolution model for the formation of ultralong-period pulsars. The model involves two key stages: first, a neutron star (NS) in wide binaries undergoes an effective spin-down phase through wind-fed accretion from its massive stellar companion; second, the supernova explo...

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When a neutron star (NS) intercepts gas from a nondegenerate star, e.g., in a tidal disruption event, a common-envelope phase, or the collapsing core of a massive star, photons become trapped in the hot flow around the NS. This gas forms a radiatively inefficient accretion flow (RIAF) until the dens...

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Sound speed can be an important tool in unravelling the nature of matter at the cores of neutron stars. In this study, we investigate three major classes of equations of state: monotonic, nonmonotonic, and discontinuous, depending on the nature of the sound speed in neutron stars. The monotonic equa...

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The nondetection of periodicity related to rotation challenges magnetar models for fast radio bursts (FRBs) with FRB emission from close to the magnetar surface. Moreover, a bimodal distribution of the burst waiting times is widely observed in hyperactive FRBs, a significant deviation from the expon...

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We have conducted a time-resolved spectral analysis of magnetar bursts originating from SGR J1550−5418. Our analysis utilizes a two-step methodology for temporal segmentation of the data. We first generated and fitted overlapping time segments. Subsequently, we obtained nonoverlapping time segments...

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We present results of more than 13 yr of Fermi–Large Area Telescope (LAT) data analysis for the Vela pulsar from 60 MeV to 100 GeV and its pulsar wind nebula (PWN), Vela X, for E  > 1 GeV in the off-pulse phases. We find that the Vela X PWN can be best characterized using two extended components:...

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Fast radio bursts (FRBs), typically highly polarized, usually have a nearly constant polarization position angle (PA) during each burst. Some bursts show significant PA variations, and one of them was claimed to have a PA variation pattern consistent with the prediction of the rotating vector model...

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Gravitational-wave astronomy shows great promise in determining nuclear physics in a regime not accessible to terrestrial experiments. We introduce physics-informed priors constrained by nuclear theory and perturbative quantum chromodynamics calculations, as well as astrophysical measurements of neu...

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We write down the force-free electrodynamics equations in dipole coordinates and solve for axisymmetric normal modes corresponding to Alfvénic perturbations in the magnetosphere of a neutron star. We show that a single Alfvén wave propagating on dipole field lines spontaneously sources a fast magnet...

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Motivated by gravitational-wave observations of binary neutron-star mergers, we study the thermal index of low-density, high-temperature dense matter. We use the virial expansion to account for nuclear interaction effects. We focus on the region of validity of the expansion, which reaches 10 ^−3 fm...

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We investigate the effects of temperature on the properties of the inner crust of a non-accreting neutron star. To this aim, we employ two different treatments: the compressible liquid drop model (CLDM) and the temperature-dependent extended Thomas–Fermi (TETF) method. Our systematic comparison show...

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Accurate distance measurements to supernova remnants (SNRs) are essential for determining their physical parameters, such as size, age, and explosion energy, and for constraining the properties of associated neutron stars (NSs). We present an extinction–distance method that combines precise Gaia DR3...

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Transitional millisecond pulsars (tMSPs) bridge the evolutionary gap between accreting neutron stars in low-mass X-ray binaries and millisecond radio pulsars. These systems exhibit a unique subluminous X-ray state characterized by the presence of an accretion disk and rapid switches between high and...

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Several phenomenological aspects of low-luminosity neutron star transients, such as atolls, remain poorly understood. One such source, MAXI J1807+132, entered its latest outburst in 2023 July. To thoroughly characterize this outburst, we conducted an extensive observational campaign spanning radio t...

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