相关论文: High Mass X-ray Binaries in the NIR : Orbital solu…
We report near-infrared radial velocity measurements of the recently identified donor star in the high mass X-ray binary system OAO 1657-415 obtained in the H band using ISAAC on the VLT. Cross-correlation methods were employed to construct…
Determining the maximum possible neutron star (NS) mass places limits on the equation of state (EoS) of ultra-dense matter. The mass of NSs in low mass X-ray binaries can be determined from the binary mass function, providing independent…
Determining the type of matter that is inside a neutron star (NS) has been a long-standing goal of astrophysics. Despite this, most of the NS equations of state (EOS) that predict maximum masses in the range 1.4-2.8 solar masses are still…
OAO1657-415 is only the seventh eclipsing X-ray pulsar known and therefore has the potential to yield only the seventh mass of a neutron star in an X-ray binary. Here we report photometric and spectroscopic observations of candidates for…
We intended to measure the radial velocity curve of the supergiant companion to the eclipsing high mass X-ray binary pulsar EXO1722-363 and hence determine the stellar masses of the components. We used a set of archival K$_{\rm s}$-band…
We analyze the currently available observations of X-ray binaries in a consistent way, to re-determine the masses of the neutron stars in these systems. In particular, our attention is focussed on a realistic and consistent assessment of…
This review summarizes the observational constraints on the mass spectrum of compact objects in X-ray binaries. We currently have 20 X-ray binaries with confirmed black holes, based on dynamical information (i.e. mass in excess of 3 Msun).…
A neutron star low-mass X-ray binary is a binary stellar system with a neutron star and a low-mass companion star rotating around each other. In this system the neutron star accretes mass from the companion, and as this matter falls into…
The maximum mass of a neutron star has important implications across multiple research fields, including astrophysics, nuclear physics and gravitational wave astronomy. Compact binary millisecond pulsars (with orbital periods shorter than…
For some neutron stars (NSs) in the binary systems, the masses have been accurately measured. While for the isolated neutron stars (INSs), no mass measurement has been reported yet. The situation will change soon thanks to the successful…
We report near-infrared observations of the supergiant donor to the eclipsing high mass X-ray binary pulsar IGR J18027-2016. We aim to determine its spectral type and measure its radial velocity curve and hence determine the stellar masses…
Neutron stars in X-ray binary systems are fascinating objects that display a wide range of timing and spectral phenomena in the X-rays. Not only parameters of the neutron stars, like magnetic field strength and spin period evolve in their…
X-ray binaries are excellent laboratories to study collapsed objects. On the one hand, transient X-ray binaries contain the best examples of stellar-mass black holes while persistent X-ray binaries mostly harbour accreting neutron stars.…
The measurement or constraint of the masses of neutron stars and their binary companions tests theories of neutron star structure and of pulsar formation and evolution. We have measured the rate of the general relativistic advance of the…
The obvious lack of the binary stellar systems that contain neutron stars (NS) is observed at present. Partly it is caused by the fact that it is very difficult to detect neutron star in a binary system if this relativistic component does…
There are now about fifty known radio pulsars in binary systems, including at least five in double neutron star binaries. In some cases, the stellar masses can be directly determined from measurements of relativistic orbital effects. In…
In recent years, the number of pulsars with secure mass measurements has increased to a level that allows us to probe the underlying neutron star (NS) mass distribution in detail. We critically review the radio pulsar mass measurements. For…
We present an improved method for determining the mass of neutron stars in eclipsing X-ray pulsar binaries and apply the method to six systems, namely Vela X-1, 4U 1538-52, SMC X-1, LMC X-4, Cen X-3, and Her X-1. In previous studies to…
A pure nucleonic equation of state (EoS) for beta equilibrated charge neutral neutron star (NS) matter is determined using density dependent effective NN interaction. This EoS is found to satisfy both the constraints from the observed…
Swift J1749.4-2807 is a transient accreting millisecond X-ray pulsars, the first that displayed X-ray eclipses. Therefore it holds a great potential for accurate mass measurements in a low mass X-ray binary system. The determination of the…