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Supernovae (SNe) with strong interactions with circumstellar material (CSM) are promising candidate sources of high-energy neutrinos and gamma rays, and have been suggested as an important contributor to Galactic cosmic rays beyond 1 PeV.…

高能天体物理现象 · 物理学 2019-03-27 Kohta Murase , Anna Franckowiak , Keiichi Maeda , Raffaella Margutti , John F. Beacom

It has been noted for a long time that the spectra of observed continuum emissions in many solar flares are consistent with double power laws with a hardening at energies $\sim > $ 300 keV. It is now largely believed that at least in…

太阳与恒星天体物理 · 物理学 2015-06-15 Gang. Li , XiangLiang Kong , Gary Zank , Yao Chen

We report the discovery of a faint H-alpha pulsar wind nebula (PWN) powered by the radio pulsar B0740-28. The characteristic bow-shock morphology of the PWN implies a direction of motion consistent with the previously measured velocity…

天体物理学 · 物理学 2009-11-07 D. Heath Jones , Ben W. Stappers , Bryan M. Gaensler

Pulsar wind nebulae (PWNe) are bubbles of relativistic particles, powered by the rotational energy loss of the central pulsars. The Crab Nebula, powered by the Milky Way's most energetic pulsar, was discovered by the Large High Altitude Air…

高能天体物理现象 · 物理学 2026-03-17 The LHAASO Collaboration

We study electron and positron acceleration at the termination shock of a striped pulsar wind. Drift motion along the shock surface keeps either electrons or positrons -but not both, close to the equatorial plane of the pulsar, where they…

高能天体物理现象 · 物理学 2019-09-16 Gwenael Giacinti , John G. Kirk

A rotating pulsar creates a surrounding pulsar wind nebula (PWN) by steadily releasing an energetic wind into the interior of the expanding shockwave of supernova remnant or interstellar medium. At the termination shock of a PWN, the…

等离子体物理 · 物理学 2020-07-15 Yingchao Lu , Fan Guo , Patrick Kilian , Hui Li , Chengkun Huang , Edison Liang

In the present paper we discuss the modifications introduced into the first-order Fermi shock acceleration process due to a finite extent of diffusive regions near the shock or due to boundary conditions leading to an increased particle…

天体物理学 · 物理学 2009-10-28 M. Ostrowski , R. Schlickeiser

Pulsar wind nebulae (PWNe) are one of the most energetic galactic sources with bright emissions from radio waves to very high-energy gamma-rays. We perform wideband X-ray spectroscopy of four energetic PWNe, N157B, PSR J1813-1749, PSR…

高能天体物理现象 · 物理学 2022-08-24 Aya Bamba , Shinpei Shibata , Shuta J. Tanaka , Koji Mori , Hiroyuki Uchida , Yukikatsu Terada , Wataru Ishizaki

We present a new model for the spectral evolution of Pulsar Wind Nebulae inside Supernova Remnants. The model couples the long-term dynamics of these systems, as derived in the 1-D approximation, with a 1-zone description of the spectral…

高能天体物理现象 · 物理学 2017-02-22 N. Bucciantini , J. Arons , E. Amato

The standard approach to the long term evolution of pulsar wind nebulae (PWNe) is based on one-zone models treating the nebula as a uniform system. In particular for the late phase of evolved systems, many of the generally used…

高能天体物理现象 · 物理学 2020-10-07 R. Bandiera , N. Bucciantini , J. Martin , B. Olmi , D. F. Torres

We study four young Pulsar Wind Nebulae (PWNe) detected in TeV gamma-rays, G21.5-0.9, G54.1+0.3, Kes 75, and G0.9+0.1, using the spectral evolution model developed and applied to the Crab Nebula in our previous work. We model the evolution…

高能天体物理现象 · 物理学 2015-05-30 Shuta J. Tanaka , Fumio Takahara

In the recent paper we calculated the $\gamma$-ray spectra from pulsar wind nebulae (PWNe), assuming that a significant amount of the pulsar rotational energy is converted into relativistic nuclei. These nuclei accelerate leptons which are…

天体物理学 · 物理学 2009-11-07 W. Bednarek

We report on a sensitive survey for radio pulsar wind nebulae (PWN) towards 27 energetic and/or high velocity pulsars. Observations were carried out at 1.4 GHz using the Very Large Array and the Australia Telescope Compact Array, and…

天体物理学 · 物理学 2015-06-24 B. M. Gaensler , B. W. Stappers , D. A. Frail , D. A. Moffett , S. Johnston , S. Chatterjee

Evolution of pulsar wind nebulae (PWNe) could be expected to leave imprints in $\gamma$-rays. We suggest that intriguing GeV-TeV spectral energy distribution (SED) of HESS J1809$-$193 and Fermi-LAT source J1810.3$-$1925e is very likely to…

高能天体物理现象 · 物理学 2025-01-16 Jiaxu Sun , Yang Chen , Yiwei Bao , Xiao Zhang , Xin Zhou

The vast majority of Pulsar Wind Nebulae (PWNe) present in the Galaxy is formed by middle-aged systems characterized by a strong interaction of the PWN itself with the supernova remnant (SNR). Unfortunately, modelling these systems can be…

高能天体物理现象 · 物理学 2023-08-16 R. Bandiera , N. Bucciantini , B. Olmi , D. F. Torres

Nonlinear electromagnetic waves with superluminal phase velocity can propagate in the winds around isolated pulsars, and around some pulsars in binary systems. Using a short-wavelength approximation, we find and analyze an integrable system…

高能天体物理现象 · 物理学 2015-06-15 Iwona Mochol , John G. Kirk

If taken into account, the transmission of the particle-scattering turbulence --in addition to just the particles-- through the shock front can change the effective compression ratio felt by the accelerating particles significantly from the…

天体物理学 · 物理学 2007-12-12 Joni Tammi

The curvature in blazar spectrum has the potential to understand the particle dynamics in jets. We performed a detailed analysis of simultaneous Swift-XRT (0.3-10 keV) and NuSTAR (3-79 keV)} observations of Mkn 421. Our analysis of NuSTAR…

高能天体物理现象 · 物理学 2024-04-24 C. Baheeja , S. Sahayanathan , F. M. Rieger , C. D. Ravikumar

The theory of first order Fermi acceleration at shocks assumes that particles diffuse due to scattering off slow-moving magnetic irregularities. However, cosmic rays are closely tied to magnetic field lines, and the transport process,…

天体物理学 · 物理学 2011-05-23 P. Duffy , J. G. Kirk , Y. A. Gallant , R. O. Dendy

Over three thousand pulsars have been discovered, but none have been confirmed to be younger than a few hundred years. Observing a pulsar after a supernova explosion will help us understand the properties of newborn ones, including their…

高能天体物理现象 · 物理学 2023-08-21 Shuta J. Tanaka , Kazumi Kashiyama