Related papers: RX J1856-3754: Evidence for a Stiff EOS
We observed the isolated neutron star RX J2143.0+0654 with the Hubble Space Telescope (HST) in the UVOIR wavelength range (0.14-1.7 $\mu$m). The UV part is consistent with a Rayleigh-Jeans tail of a thermal spectrum, $f_\nu\propto \nu^2$,…
The isolated neutron star RX J0806.4-4123 was observed with XMM-Newton in November 2000. The data from the three EPIC instruments allowed us (i) to derive an improved X-ray position to an accuracy of 2-3'', (ii) to accumulate the first…
In the line-of-sight toward the DO-type white dwarf RX J0503.9-2854, the density of the interstellar medium (ISM) is very low, and thus the contamination of the stellar spectrum almost negligible. This allows us to identify many metal lines…
We present limits to the log N - log S curve for isolated neutron stars, both cooling and accreting neutron stars, which are not active as radio pulsars, as observed with the ROSAT All-Sky Survey and compare it with theoretical…
A recent analysis on the properties of the XTE J1814-338 pulsar yielded a small radius value around ~ 7 km. Notably, this estimation is significantly lower compared to the currently inferred values for the radius of neutron stars (as they…
In the ROSAT Bright Survey (RBS) we have almost completely optically identified the brightest ~2000 high-galactic latitude sources from the ROSAT All-Sky Survey Bright Source Catalogue (1RXS). A small number of sources has empty X-ray error…
We report the results of a deep XMM-Newton observation of the radio-faint $\gamma$-ray pulsar J1741-2054 and its nebula together with the analysis of 5 years of Fermi LAT data. The X-ray spectrum of the pulsar is consistent with an absorbed…
With a parallactic distance of 170 pc, PSR J2144-3933 is the closest isolated radio pulsar currently known. It is also the slowest (P = 8.51 s) and least energetic (Edot = 2.6E28 erg/s) radio pulsar; its radio emission is difficult to…
We report on the analysis of new X-ray data obtained with XMM-Newton and Chandra from two ROSAT-discovered X-ray dim isolated neutron stars. RX J0806.4-4123 was observed with XMM-Newton in April 2003, 2.5 years after the first observation.…
Properties and structure of neutron stars are determined by the equation of state (EOS) of neutron-rich stellar matter. While the collective flow and particle production in relativistic heavy-ion collisions have constrained tightly the EOS…
The determination of the equation of state (EOS) for nuclear matter has been one of the biggest problems in nuclear astrophysics, because the EOS is essential for determining the properties of neutron stars. To constrain the…
We report on follow-up observations with XMM-Newton, the FORS2 instrument at the ESO-VLT, and FAST, aiming to characterise the nature of five thermally emitting isolated neutron star (INS) candidates recently discovered from searches in the…
Multiwavelength studies of the seven identified X-ray dim isolated neutron stars (XDINSs) offer a unique opportunity to investigate their surface thermal and magnetic structure and the matter-radiation interaction in presence of strong…
Aims: PSR J0855-4644 is a fast-spinning, energetic pulsar discovered at radio wavelengths near the south-eastern rim of the supernova remnant RX J0852.0-4622. A follow-up observation revealed the pulsar's X-ray counterpart and a slightly…
The nearby isolated neutron stars are a group of seven relatively slowly rotating neutron stars that show thermal X-ray spectra, most with broad absorption features. They are interesting both because they may allow one to determine…
We report on the results of a deep XMM-Newton observation of RBS 1774, the most recent dim isolated neutron star candidate found in the ROSAT archive data. Spectral and timing analysis of the high-quality PN and MOS data confirm the…
The recent discovery of burst oscillations at 1122 Hz in the x-ray transient XTE J1739-285, together with the measurement of the mass of the binary millisecond pulsar PSR J0751+1807 (2.1 +- 0.2 solar masses) can finally allow us to put…
X-ray observations unveiled various types of radio-silent Isolated Neutron Stars (INSs), phenomenologically very diverse, e.g. the Myr old X-ray Dim INS (XDINSs) and the kyr old magnetars. Although their phenomenology is much diverse, the…
The observation of $1.97\pm0.04$ solar-mass neutron-like star gives constraint on the equation of state (EOS) of cold, condensed matter. In this paper, the EOS for both pure quark star and hybrid star with a quark core described by…
The properties of strange quark stars are studied within the quasi-particle model. Taking into account the chemical equilibrium and charge neutrality, the EOS of $ (2+1) $-flavor quark matter is obtained. We illustrate the parameter spaces…