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Related papers: Bow shock sources close to the Galactic centre

200 papers

We investigate the occurrence of stellar bow shocks around high-mass X-ray binaries (HMXBs) in the Galaxy. We seek to conduct a survey of HMXBs in the mid-infrared to search for the presence of bow shocks around these objects. Telescopes…

Solar and Stellar Astrophysics · Physics 2019-01-09 M. Prisegen

Context. There is a population of runaway stars that move at extremely high speeds with respect to their surroundings. The fast motion and the stellar wind of these stars, plus the wind-medium interaction, can lead to particle acceleration…

High Energy Astrophysical Phenomena · Physics 2022-05-11 J. R. Martinez , S. del Palacio , V. Bosch-Ramon , G. E. Romero

We aim to interpret the radio emission of stellar bow shocks and assess under which conditions it could be either thermal or non-thermal, and how to use the observational data to infer their physical properties. We used an extended…

High Energy Astrophysical Phenomena · Physics 2023-12-20 Javier Rodrigo Martinez , Santiago del Palacio , Valentí Bosch-Ramon

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…

Astrophysics of Galaxies · Physics 2021-12-15 S. K. Ocker , J. M. Cordes , S. Chatterjee , T. Dolch

Far-infrared Herschel/PACS images at 70 and 160 micron of a sample of 78 Galactic evolved stars are used to study the (dust) emission structures, originating from stellar wind-ISM interaction. In addition, two-fluid hydrodynamical…

We performed a spectro-morphological analysis of the diffuse emission in the Galactic center region with H.E.S.S. gamma-ray data. We relied on templates to model the diffuse emissions (the Galactic center ridge and the foreground component)…

High Energy Astrophysical Phenomena · Physics 2025-07-02 J. Devin , A. Lemière , K. Streil , R. Terrier , C. van Eldik

We present results of deep 153 ks Chandra observations of the hot, 11 keV, galaxy cluster associated with the radio galaxy 3C 438. By mapping the morphology of the hot gas and analyzing its surface brightness and temperature distributions,…

High Energy Astrophysical Phenomena · Physics 2017-01-18 Deanna L. Emery , Akos Bogdan , Ralph P. Kraft , Felipe Andrade-Santos , William R. Forman , Martin J. Hardcastle , Christine Jones

We present mid-infrared N- and Q-band photometry of the Galactic Center from images obtained with the mid-infrared camera VISIR at the ESO VLT in May 2004. The high resolution and sensitivity possible with VISIR enables us to investigate a…

Astrophysics · Physics 2009-11-11 T. Viehmann , A. Eckart , R. Schoedel , J. -U. Pott , J. Moultaka

Millimeter very long baseline interferometry will soon produce accurate images of the closest surroundings of the supermassive compact object at the center of the Galaxy, Sgr A*. These images may reveal the existence of a central faint…

General Relativity and Quantum Cosmology · Physics 2016-05-25 F. H. Vincent , Z. Meliani , P. Grandclement , E. Gourgoulhon , O. Straub

Here we present a new bowshock blue-shifted source in the close vicinity of Sgr A* that we name X8. We use data-sets that are based on SINFONI observations with the Very Large Telescope. We can trace the source between 2006 and 2016 in the…

Astrophysics of Galaxies · Physics 2019-04-17 F. Peißker , M. Zajacek , A. Eckart , N. Sabha , B. Shahzamanian , M. Parsa

Gamma ray observations have found evidence of an extremely energetic outflow emanating from the Galactic Centre, and an `excess' of emission at GeV energies towards the Galactic Centre over that expected from current models. Determining…

Astrophysics of Galaxies · Physics 2018-05-17 Steven N. Longmore , J. M. Diederik Kruijssen

The FUGIN CO survey with the Nobeyama 45-m Telescope revealed the 3D structure of a galactic shock wave in the tangential direction of the 4-kpc molecular arm. The shock front is located at G30.5+00.0+95 km/s on the up-stream (lower…

Astrophysics of Galaxies · Physics 2019-07-24 Y. Sofue , M. Kohno , K. Torii , T. Umemoto , N. Kuno , K. Tachihara , T. Minamidani , S. Fujita , M. Matsuo , A. Nishimura , Y. Tsuda , M. Seta

We focus on a sample of 42 sources in the vicinity of the bow-shock source IRS 1W (N-sources), located at the distance of $6.05''$ north-east of the supermassive black hole (SMBH) Sagittarius A* (Sgr A*), within the radius of $1.35''$. We…

Astrophysics of Galaxies · Physics 2024-11-15 S. Elaheh Hosseini , Andreas Eckart , Michal Zajaček , Silke Britzen , Harshitha K. Bhat , Vladimír Karas

The interaction of high-velocity neutron stars with the interstellar medium produces bow shock nebulae, where the relativistic neutron star wind is confined by ram pressure. We present multi-wavelength observations of the Guitar Nebula,…

Astrophysics · Physics 2007-05-23 S. Chatterjee , J. M. Cordes

The spectra emitted from clouds near the Galactic Centre are investigated calculating the UV-optical-IR lines using the physical parameters and the element abundances constrained by the fit of mid-IR observations. The characteristic line…

Astrophysics of Galaxies · Physics 2015-05-20 M. Contini , I. Goldman

We present a new directly-observable statistic which uses sky position and proper motion of stars near the Galactic center massive black hole to identify populations with high orbital eccentricities. It is most useful for stars with large…

Astrophysics of Galaxies · Physics 2015-06-15 Ann-Marie Madigan , Oliver Pfuhl , Yuri Levin , Stefan Gillessen , Reinhard Genzel , Hagai B. Perets

We present improved relative astrometry for stars within the central half parsec of our Galactic Center based on data obtained with the 10 m W. M. Keck Observatory from 1995 to 2017. The new methods used to improve the astrometric precision…

We present evidence for a Galactic North-South asymmetry in the number density and bulk velocity of solar neighborhood stars. The number density profile, which is derived from main-sequence stars in the Sloan Digital Sky Survey, shows a…

Astrophysics of Galaxies · Physics 2015-06-04 Lawrence M. Widrow , Susan Gardner , Brian Yanny , Scott Dodelson , Hsin-Yu Chen

Using adaptive optics at the Gemini North telescope we have obtained a K-band spectrum of the star near the center of the luminous Galactic center bowshock IRS8, as well as a spectrum of the bowshock itself. The stellar spectrum contains…

Astrophysics · Physics 2011-02-11 T. R. Geballe , F. Najarro , F. Rigaut , J. -R. Roy

The bow shocks of runaway stars with strong stellar winds of over 2000 km s$^{-1}$ can serve as particle acceleration sites. The conversion from stellar wind luminosity into particle acceleration power has an efficiency of the same order of…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Yukikatsu Terada , Makoto S. Tashiro , Aya Bamba , Ryo Yamazaki , Tomomi Kouzu , Shu Koyama , Hiromi Seta