Related papers: A Quarter Century of Guitar Nebula/Filament Evolut…

The Guitar nebula is a spectacular example of an H-alpha bow shock nebula produced by the interaction of a neutron star with its environment. The radio pulsar B2224+65 is traveling at ~800--1600 km/s (for a distance of 1--2 kpc), placing it…

We have detected weak soft X-ray emission from the Pulsar Wind Nebula trailing the high velocity star PSR 2224+65 (the `Guitar Nebula'). This X-ray flux gives evidence of \gamma~10^7 eV particles in the pulsar wind and constrains the…

Context: A mysterious X-ray nebula, showing a remarkably linear geometry, was recently discovered close to the Guitar Nebula, the bow-shock nebula associated with B2224+65, which is the fastest pulsar known. The nature of this X-ray feature…

Based on three years of deep observations of the Galactic center with the Chandra X-ray Observatory, we report the discovery of changes in the intensities and morphologies of two hard X-ray nebulosities. The nebulosities are dominated by…

Context. We propose that the X-ray filaments emerging from selected bow shock pulsar wind nebulae are due to a charge-separated outflow of electrons and/or positrons escaping the nebula and propagating along the local Galactic magnetic…

We present an X-ray morphological and spectroscopic study of the pulsar B2224+65 and its apparent jet-like X-ray features based on two epoch Chandra observations. The main X-ray feature, which shows a large directional offset from the…

The Guitar Nebula is an H-alpha nebula produced by the interaction of the relativistic wind of a very fast pulsar, PSR B2224+65, with the interstellar medium. It consists of a ram-pressure confined bow shock near its head and a series of…

Guitar nebula is a prime example of a class of bow-shock pulsar wind nebulae (PWNe), powered by a wind of a supersonically moving neutron star. Bow-shock PWNe can probe particle acceleration processes in relativistic pulsar winds, as well…

\xmm ~observations of the X-ray feature 1SAX J0617.1+2221 in the IC443 supernova remnant are reported.We resolve the structure of the nebula into a compact core with a hard spectrum of photon index $\gamma= 1.63^{+0.11}_{-0.10}$ in the…

The new Spectrum Roentgen Gamma (SRG) eROSITA X-ray telescope has a superior response to extended soft X-rays, which makes it ideal for studying low X-ray surface brightness emission of cosmic filaments. We search for extended X-ray…

Stellar bow shocks are observed in a variety of interstellar environments and are shaped by the conditions of gas in the interstellar medium (ISM). In situ measurements of turbulent density fluctuations near stellar bow shocks are only…

The Crab Nebula is one of the brightest and most stable sources in the X-ray sky. Year-scale flux variation from the object was recently revealed in the hard X-ray band by four satellites. This marked the first detection of year-scale…

New X-ray and optical observations shed light on the remarkable X-ray filament of the Gamma-ray pulsar PSR~J2030+4415. Images of the associated H$\alpha$ bow shock's evolution over the past decade compared with its velocity structure…

NGC 1275 in the centre of the Perseus cluster of galaxies, Abell 426, is surrounded by a spectacular filamentary Halpha nebula. Deep Chandra X-ray imaging has revealed that the brighter outer filaments are also detected in soft X-rays. This…

The synchrotron-emitting nebulae formed by energetic winds from young pulsars provide information on a wide range phenomena that contribute to their structure. High resolution X-ray observations reveal jets and toroidal structures in many…

We examine deep Chandra X-ray observations of the Centaurus cluster of galaxies, Abell 3526. Applying a gradient magnitude filter reveals a wealth of structure, from filamentary soft emission on 100pc (0.5 arcsec) scales close to the…

We report the detection of a point source CXO J172337.5-373442 in a Chandra field with a high significance (26.7 sigma), and the discovery (4 sigma) of a 48" long X-ray tail emanating from the point source. The X-ray spectra of both the…

We analyse the remnants of CK Vul (Nova Vul 1670) using optical imaging and spectroscopy. The imaging, obtained between 1991 and 2010, spans 5.6% of the life-time of the nebula. The flux of the nebula decreased during the last 2 decades.…

The filamentary nebula encompassing the central galaxy of the Perseus Cluster, NGC 1275, is a complex structure extending dozens of kiloparsecs from NGC 1275. Decades of previous works have focused on establishing the primary formation and…

We present results of deep integral field spectroscopy observations using high resolution optical (4150-7200 A) VIMOS VLT spectra, of NGC 4696, the dominant galaxy in the Centaurus cluster (Abell 3526). After the Virgo cluster, this is the…