Particle acceleration and non-thermal emission in Pulsar Wind Nebulae from relativistic MHD simulations

AbstractSome fast-moving pulsars, such as the Guitar and the Lighthouse, exhibit asymmetric non-thermal emission features that extend well beyond their ram pressure confined pulsar wind nebulae (PWNe). Based on our 3D relativistic simulations, we analytically explain these features as kinetically streaming pulsar wind particles that escaped into the interstellar medium (ISM) due to reconnection between the PWN and ISM magnetic fields. The structure of the reconnecting magnetic fields at the incoming and outgoing regions produces highly asymmetric magnetic bottles therefore and result in asymmetric extended features. For the features to become visible, the ISM magnetic field should be sufficiently high, BISM > 10 $\mu$G. We also discuss archival observations of PWNe displaying evidence of kinetic jets: the Dragonfly PWN (PSR J2021 + 3651), G327.1–1.1, and MSH 11–62, the latter two of which exhibit symmetric ‘snail eyes’ morphologies. We suggest that in those cases the pulsar is moving along the ambient magnetic field in a frisbee-type configuration.

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Searching for X-ray counterparts of Fermi Gamma-ray pulsars in Suzaku observations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312013130 ◽

2011 ◽

Vol 7 (S279) ◽

pp. 317-318 ◽

Cited By ~ 1

Author(s):

Yu Aoki ◽

Takahiro Enomoto ◽

Yoichi Yatsu ◽

Nobuyuki Kawai ◽

Takeshi Nakamori ◽

...

Keyword(s):

Gamma Ray ◽

Thermal Emission ◽

Flux Ratio ◽

Radio Pulsars ◽

Pulsar Wind Nebulae ◽

X Ray ◽

Absorbed Power ◽

Pulsar Wind ◽

Error Circle

AbstractWe report the Suzaku follow-up observations of the Gamma-ray pulsars, 1FGL J0614,13328, J1044.55737, J1741.82101, and J1813.31246, which were discovered by the Fermi Gamma-ray observatory. Analysing Suzaku/XIS data, we detected X-ray counterparts of these pulsars in the Fermi error circle and interpreted their spectra with absorbed power-law functions. These results indicate that the origin of these X-ray sources is non-thermal emission from the pulsars or from Pulsar Wind Nebulae (PWNe) surrounding them. Moreover we found that J1741.82101 exhibits a peculiar profile: spin-down luminosity vs flux ratio between X- and gamma-rays is unusually large compared to usual radio pulsars.

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Non-thermal emission from pulsar-wind nebulae in starburst galaxies

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/sls025 ◽

2012 ◽

Vol 429 (1) ◽

pp. L70-L74 ◽

Cited By ~ 5

Author(s):

S. Ohm ◽

J. A. Hinton

Keyword(s):

Thermal Emission ◽

Starburst Galaxies ◽

Pulsar Wind Nebulae ◽

Pulsar Wind

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PARTICLE ACCELERATION AT THE TERMINATION SHOCK OF STRIPED PULSAR WINDS

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512004539 ◽

2012 ◽

Vol 08 ◽

pp. 144-150 ◽

Cited By ~ 2

Author(s):

LORENZO SIRONI ◽

ANATOLY SPITKOVSKY

Keyword(s):

Magnetic Field ◽

Particle Acceleration ◽

Magnetic Energy ◽

Termination Shock ◽

Larmor Radius ◽

Pulsar Wind Nebulae ◽

Field Polarity ◽

Particle In Cell ◽

Post Shock ◽

Pulsar Wind

The relativistic wind of pulsars consists of toroidal stripes of opposite magnetic field polarity, separated by current sheets of hot plasma. By means of multi-dimensional particle-in-cell simulations, we investigate particle acceleration and magnetic field dissipation at the termination shock of a relativistic striped pulsar wind. At the shock, the flow compresses and the alternating fields annihilate by driven magnetic reconnection. Irrespective of the stripe wavelength λ or the wind magnetization σ (in the regime σ ≫1 of magnetically dominated flows), shock-driven reconnection transfers all the magnetic energy of alternating fields to the particles. In the limit λ/(rL σ) ≫ 1, where rL is the relativistic Larmor radius in the wind, the post-shock spectrum approaches a flat power-law tail with slope around -1.5, populated by particles accelerated by the reconnection electric field. Our findings place important constraints on the models of non-thermal radiation from Pulsar Wind Nebulae.

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