NICER Detection of Thermal X-Ray Pulsations from the Massive Millisecond Pulsars PSR J0740+6620 and PSR J1614–2230

The aim of this work is to study the possible effects and biases on the radius constraints for rotation-powered millisecond pulsars when using Thomson approximation to describe electron scattering in the atmosphere models, instead of using exact formulation for Compton scattering. We compare the differences between the two models in the energy spectrum and angular distribution of the emitted radiation. We also analyse a self-generated, synthetic, phase-resolved energy spectrum, based on Compton atmosphere and the most X-ray luminous, rotation-powered millisecond pulsars observed by the Neutron star Interior Composition ExploreR (NICER). We derive constraints for the neutron star parameters using both the Compton and Thomson models. The results show that the method works by reproducing the correct parameters with the Compton model. However, biases are found in both the size and the temperature of the emitting hotspot, when using the Thomson model. The constraints on the radius are still not significantly changed, and therefore the Thomson model seems to be adequate if we are interested only in the radius measurements using NICER.

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Thermal X-ray emission identified from the millisecond pulsar PSR J1909–3744

Astronomy and Astrophysics ◽

10.1051/0004-6361/201732040 ◽

2019 ◽

Vol 627 ◽

pp. A141 ◽

Cited By ~ 2

Author(s):

N. A. Webb ◽

D. Leahy ◽

S. Guillot ◽

N. Baillot d’Etivaux ◽

D. Barret ◽

...

Keyword(s):

Neutron Star ◽

Equation Of State ◽

Thermal Emission ◽

Black Body ◽

Millisecond Pulsar ◽

Distance Measurements ◽

Millisecond Pulsars ◽

X Ray ◽

Link Type

Context. Pulsating thermal X-ray emission from millisecond pulsars can be used to obtain constraints on the neutron star equation of state, but to date only five such sources have been identified. Of these five millisecond pulsars, only two have well-constrained neutron star masses, which improve the determination of the radius via modelling of the X-ray waveform. Aims. We aim to find other millisecond pulsars that already have well-constrained mass and distance measurements that show pulsed thermal X-ray emission in order to obtain tight constraints on the neutron star equation of state. Methods. The millisecond pulsar PSR J1909–3744 has an accurately determined mass, M = 1.54 ± 0.03 M⊙ (1σ error) and distance, D = 1.07 ± 0.04 kpc. We analysed XMM-Newton data of this 2.95 ms pulsar to identify the nature of the X-ray emission. Results. We show that the X-ray emission from PSR J1909–3744 appears to be dominated by thermal emission from the polar cap. Only a single component model is required to fit the data. The black-body temperature of this emission is $ {kT}=0.26^{0.03}_{0.02} $ keV and we find a 0.2–10 keV un-absorbed flux of 1.1 × 10−14 erg cm−2 s−1 or an un-absorbed luminosity of 1.5 × 1030 erg s−1. Conclusion. Thanks to the previously determined mass and distance constraints of the neutron star PSR J1909–3744, and its predominantly thermal emission, deep observations of this object with future X-ray facilities should provide useful constraints on the neutron star equation of state.

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X-ray Emission Characteristics of Pulsars

Symposium - International Astronomical Union ◽

10.1017/s0074180900162771 ◽

2000 ◽

Vol 195 ◽

pp. 49-60

Author(s):

W. Becker

Keyword(s):

Neutron Star ◽

Neutron Stars ◽

Emission Characteristics ◽

Millisecond Pulsars ◽

X Ray ◽

Emission Properties ◽

Important Progress

Recent X-ray observatories such as ROSAT, ASCA, RXTE, BeppoSAX, and Chandra have achieved important progress in neutron star and pulsar astronomy. The identification of Geminga as a rotation-powered pulsar, the discovery of X-ray emission from millisecond pulsars, and the identification of cooling neutron stars are only a few of the fascinating results. In the following, I will give a brief review on the X-ray emission properties of rotation-powered pulsars and their wind nebulae.

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High-precision X-Ray Timing of Three Millisecond Pulsars with NICER: Stability Estimates and Comparison with Radio

The Astrophysical Journal ◽

10.3847/1538-4357/ab0966 ◽

2019 ◽

Vol 874 (2) ◽

pp. 160 ◽

Cited By ~ 8

Author(s):

J. S. Deneva ◽

P. S. Ray ◽

A. Lommen ◽

S. M. Ransom ◽

S. Bogdanov ◽

...

Keyword(s):

High Precision ◽

Stability Estimates ◽

Millisecond Pulsars ◽

X Ray

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Super-Eddington Accretion in the Formation of Low-Mass X-ray Binaries and Millisecond Pulsars

International Astronomical Union Colloquium ◽

10.1017/s0252921100044213 ◽

1997 ◽

Vol 163 ◽

pp. 828-829 ◽

Cited By ~ 3

Author(s):

R. F. Webbink ◽

V. Kalogera

Keyword(s):

Mass Transfer ◽

Initial Phase ◽

Transfer Rate ◽

Birth Rate ◽

Mass Transfer Rate ◽

Millisecond Pulsars ◽

X Ray ◽

Low Mass ◽

Orbital Periods ◽

X Ray Binaries

AbstractConsiderations of donor star stability, age, and mass transfer rate show that low-mass X-ray binaries and binary millisecond pulsars with orbital periods longer than a few days must have survived an initial phase of super-Eddington mass transfer. We review the physical arguments leading to this conclusion, and examine its implications for the apparent discrepancy between the death rate for low-mass X-ray binaries and the birth rate of binary millisecond pulsars.

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