Retraction Note to: X-ray observations of PSR B0355+54 and its pulsar wind nebula

We present year-scale morphological variations of the Crab Nebula revealed by the Chandra X-ray Observatory. Observations have been performed about every 1.7 years over the three years from launch. The variations are clearly recognized at two sites: the torus and the southern jet. The torus, which had been steadily expanding until 1.7 years ago, now appears to have shrunk in the latest observation. Additionally, the circular structures seen to the northeast of the torus have decayed into several arcs. On the other hand, the southern jet shows the growth of its overall kinked-structure. We discuss the nature of these variations in terms of the pulsar wind nebula mechanism.

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New insight into the origin of the GeV flare in the binary system PSR B1259-63/LS 2883 from the 2017 periastron passage

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1876 ◽

2020 ◽

Vol 497 (1) ◽

pp. 648-655

Author(s):

M Chernyakova ◽

D Malyshev ◽

S Mc Keague ◽

B van Soelen ◽

J P Marais ◽

...

Keyword(s):

Binary System ◽

Light Curve ◽

Energy Release ◽

Broad Band ◽

Strong Shock ◽

Optical Observations ◽

X Rays ◽

X Ray ◽

Inverse Compton ◽

Pulsar Wind

ABSTRACT PSR B1259-63 is a gamma-ray binary system hosting a radio pulsar orbiting around an O9.5Ve star, LS 2883, with a period of ∼3.4 yr. The interaction of the pulsar wind with the LS 2883 outflow leads to unpulsed broad-band emission in the radio, X-rays, GeV, and TeV domains. While the radio, X-ray, and TeV light curves show rather similar behaviour, the GeV light curve appears very different with a huge outburst about a month after a periastron. The energy release during this outburst seems to significantly exceed the spin-down luminosity of the pulsar and both the GeV light curve and the energy release vary from one orbit to the next. In this paper, we present for the first time the results of optical observations of the system in 2017, and also reanalyse the available X-ray and GeV data. We present a new model in which the GeV data are explained as a combination of the bremsstrahlung and inverse Compton emission from the unshocked and weakly shocked electrons of the pulsar wind. The X-ray and TeV emission is produced by synchrotron and inverse Compton emission of energetic electrons accelerated on a strong shock arising due to stellar/pulsar winds collision. The brightness of the GeV flare is explained in our model as a beaming effect of the energy released in a cone oriented, during the time of the flare, in the direction of the observer.

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High Resolution X-ray Observations of 3C 58

Symposium - International Astronomical Union ◽

10.1017/s0074180900180921 ◽

2004 ◽

Vol 218 ◽

pp. 185-188

Author(s):

Patrick Slane

Keyword(s):

High Resolution ◽

Massive Star ◽

Thermal Emission ◽

Rotation Axis ◽

Crab Nebula ◽

X Ray ◽

The Galaxy ◽

Pulsar Wind ◽

Star Surface ◽

The Crab Nebula

As the presumed remnant of SN 1181, 3C 58 houses one of the youngest known neutron stars in the Galaxy. The properties of this young pulsar and its associated pulsar wind nebula (PWN) differ considerably from those of the Crab Nebula, and may well offer a more typical example of the endpoint of massive star collapse. High resolution X-ray studies reveal structures in the inner nebula that may be associated with the pulsar wind termination shock, a jet that may be aligned with the rotation axis, and other regions of enhanced emission. Spectral variations in the PWN are consistent with the expected evolution of the postshock flow, and complex loops of emission are seen in the nebula interior. Limits on the neutron star surface temperature fall below standard cooling models, indicating that some more rapid neutrino cooling process is required. The outer regions of 3C 58 show thermal emission with enhanced levels of neon, indicative of shocked ejecta bounding the PWN.

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XMM-Newton and Geminga

Symposium - International Astronomical Union ◽

10.1017/s007418090018101x ◽

2004 ◽

Vol 218 ◽

pp. 215-218

Author(s):

Patrizia Caraveo ◽

Andrea De Luca ◽

Sandro Mereghetti ◽

Alberto Pellizzoni ◽

Giovanni Bignami ◽

...

Keyword(s):

Magnetic Field ◽

Surrounding Medium ◽

Matter Density ◽

Bow Shock ◽

Synchrotron Emission ◽

Electron Synchrotron ◽

X Ray ◽

Injection Energy ◽

Pulsar Wind ◽

Supersonic Motion

A deep XMM-Newton/EPIC observation of the field of the Geminga pulsar unveiled the presence of two elongated parallel X-ray tails trailing the neutron star. They are aligned with the object's supersonic motion, extend for ∼ 2′, and have a nonthermal spectrum produced by electron-synchrotron emission in the bow shock between the pulsar wind and the surrounding medium. Such a first ever X-ray detection of a pulsar bow shock allows us to gauge the pulsar electron injection energy and the shock magnetic field while constraining the angle of Geminga's motion and the local matter density.

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Deciphering the nature of the pulsar wind nebula CTB 87 with XMM–Newton

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3270 ◽

2019 ◽

Vol 491 (2) ◽

pp. 3013-3021 ◽

Cited By ~ 1

Author(s):

B Guest ◽

S Safi-Harb ◽

A MacMaster ◽

R Kothes ◽

B Olmi ◽

...

Keyword(s):

Supernova Remnant ◽

Thermal Emission ◽

Plasma Temperature ◽

Evolutionary Stage ◽

Reverse Shock ◽

X Ray ◽

Upper Limit ◽

Supernova Shell ◽

Pulsar Wind ◽

Hydrodynamical Simulations

ABSTRACT CTB 87 (G74.9+1.2) is an evolved supernova remnant (SNR) which hosts a peculiar pulsar wind nebula (PWN). The X-ray peak is offset from that observed in radio and lies towards the edge of the radio nebula. The putative pulsar, CXOU J201609.2+371110, was first resolved with Chandra and is surrounded by a compact and a more extended X-ray nebula. Here, we use a deep XMM–Newton observation to examine the morphology and evolutionary stage of the PWN and to search for thermal emission expected from a supernova shell or reverse shock interaction with supernova ejecta. We do not find evidence of thermal X-ray emission from the SNR and place an upper limit on the electron density of 0.05 cm−3 for a plasma temperature kT ∼ 0.8 keV. The morphology and spectral properties are consistent with a ∼20-kyr-old relic PWN expanding into a stellar wind-blown bubble. We also present the first X-ray spectral index map from the PWN and show that we can reproduce its morphology by means of 2D axisymmetric relativistic hydrodynamical simulations.

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Energy-dependent nebula extent and spatially resolved spectra of the pulsar wind nebula 3C 58

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2338 ◽

2020 ◽

Vol 498 (2) ◽

pp. 1911-1919

Author(s):

Fang-Wu Lu ◽

Quan-Gui Gao ◽

Li Zhang

Keyword(s):

Surface Brightness ◽

Spectral Energy Distribution ◽

High Energy ◽

Spatial Variations ◽

Spectral Energy ◽

X Ray ◽

Spatially Resolved ◽

Photon Index ◽

Pulsar Wind ◽

Energy Dependent

ABSTRACT 3C 58 is a pulsar wind nebula (PWN) that shows an interesting energy-dependent nebula extent and spatial variations of the photon index and surface brightness in the X-ray band. These observations provide useful information with which to study the spatially dependent radiative cooling of electrons and the energy-dependent transport mechanisms within the nebula. In this paper, the energy-dependent nebula extent and spatially resolved spectra of this PWN are investigated in the framework of a spatially dependent particle transport model. The observations of the nebula, including the photon spectral energy distribution, spatial variations of the X-ray spectrum, and measurements of the nebula extent, can be naturally explained in this model. Our results show that the energy-dependent nebula extent favours an advection–diffusion scenario with advection-dominated transport, and the variations of the nebula extent with energy in the X-ray band can be attributed to the cooling losses of high-energy electrons affected by synchrotron burn-off. Particle diffusion plays an important role in modifying the spatial variations of the photon index and surface brightness in the X-ray band. The radial extents of the nebula at radio, GeV and TeV energies are predicted by the model, indicating that the nebula extent of 3C 58 varies with energy in these bands. The analyses show that the dependence of the adiabatic cooling rate and synchrotron radiation on the spectral index of injected particles is important for changing the nebula extent at different energies.

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