Browsing by Author "Krause, M.~G.~H."

Now showing items 1-15 of 15

    • Correlated optical, X-ray, and $-ray flaring activity seen with INTEGRAL during the 2015 outburst of V404 Cygni 

      Rodriguez, J.; Cadolle Bel, M.; Alfonso-Garzón, J.; Siegert, T.; Zhang, X.-L.; Grinberg, V.; Savchenko, V.; Tomsick, J.~A.; Chenevez, J.; Clavel, M.; Corbel, S.; Diehl, R.; Domingo, A.; Gouiffès, C.; Greiner, J.; Krause, M.~G.~H.; Laurent, P.; Loh, A.; Markoff, S.; Mas-Hesse, J.~M.; Miller-Jones, J.~C.~A.; Russell, D.~M.; Wilms, J. (2015-09-23)
      After 25 years of quiescence, the microquasar V404 Cyg entered a new period of activity in June 2015. This X-ray source is known to undergo extremely bright and variable outbursts seen at all wavelengths. It is therefore ...

    • Dynamics and Energy Loss in Superbubbles 

      Krause, M.~G.~H.; Diehl, R. (2014-10-01)
      Interstellar bubbles appear to be smaller in observations than expected from calculations. Instabilities at the shell boundaries create three-dimensional (3D) effects and are probably responsible for part of this discrepancy. ...

    • Galactic winds - how to launch galactic outflows in typical Lyman-break galaxies 

      von Glasow, W.; Krause, M.~G.~H.; Sommer-Larsen, J.; Burkert, A. (2013-09-11)
      We perform hydrodynamical simulations of a young galactic disc embedded in a hot gaseous halo using parameters typical for Lyman-break galaxies (LBGs). We take into account the (static) gravitational potentials due to a ...

    • Gamma-ray spectroscopy of positron annihilation in the Milky Way 

      Siegert, T.; Diehl, R.; Khachatryan, G.; Krause, M.~G.~H.; Guglielmetti, F.; Greiner, J.; Strong, A.~W.; Zhang, X. (2016-02-01)
      Context. The annihilation of positrons in the Galaxy's interstellar medium produces characteristic gamma-rays with a line at 511 keV. This gamma-ray emission has been observed with the spectrometer SPI on ESA's INTEGRAL ...

    • Gas expulsion in massive star clusters?. Constraints from observations of young and gas-free objects 

      Krause, M.~G.~H.; Charbonnel, C.; Bastian, N.; Diehl, R. (2016-03-01)
      Context. Gas expulsion is a central concept in some of the models for multiple populations and the light-element anti-correlations in globular clusters. If the star formation efficiency was around 30 per cent and the gas ...

    • Jets and multi-phase turbulence . 

      Krause, M.~G.~H. (Memorie della Societa Astronomica Italiana, 2008-06-06)
      Jets are observed to stir up multiphase turbulence in the interstellar medium as well as far beyond the host galaxy. Here we present detailed simulations of this process. We evolve the hydrodynamics equations with optically ...

    • Large Scale Simulations of the Jet-Igm Interaction 

      Krause, M.~G.~H. (2004-08-01)
      In a parameter study extending to jet densities of 10−5 times the ambient one, I have recently shown that light large-scale jets start their lives in a spherical bow shock phase. This allows an easy description of the ...

    • Positron Annihilation in the Galaxy 

      Kierans, C.~A.; Beacom, J.~F.; Boggs, S.; Buckley, M.; Caputo, R.; Crocker, R.; De Becker, M.; Diehl, R.; Fryer, C.~L.; Griffin, S.; Hartmann, D.; Hays, E.; Jean, P.; Krause, M.~G.~H.; Linden, T.; Marcowith, A.; Martin, P.; Moiseev, A.; Oberlack, U.; Orlando, E.; Panther, F.; Prantzos, N.; Rothschild, R.; Seitenzahl, I.; Shrader, C.; Siegert, T.; Strong, A.; Tomsick, J.; Vestrand, W.~T.; Zoglauer, A. (2019-03-13)
      The 511 keV line from positron annihilation in the Galaxy was the first γ-ray line detected to originate from outside our solar system. Going into the fifth decade since the discovery, the source of positrons is still ...

    • Positron annihilation signatures associated with the outburst of the microquasar V404 Cygni 

      Siegert, T.; Diehl, R.; Greiner, J.; Krause, M.~G.~H.; Beloborodov, A.~M.; Bel, M.~C.; Guglielmetti, F.; Rodriguez, J.; Strong, A.~W.; Zhang, X. (2016-03-17)
      Microquasars1, 2, 3, 4 are stellar-mass black holes accreting matter from a companion star5 and ejecting plasma jets at almost the speed of light. They are analogues of quasars that contain supermassive black holes of 106 ...

    • RAiSE II: resolved spectral evolution in radio AGN 

      Turner, R. J.; Rogers, J.~G.; Shabala, Stanislav; Krause, M.~G.~H. (2018-01-01)
      The active galactic nuclei (AGN) lobe radio luminosities modelled in hydrodynamical simulations and most analytical models do not address the redistribution of the electron energies due to adiabatic expansion, synchrotron ...

    • Search for 511 keV Emission in Satellite Galaxies of the Milky Way with INTEGRAL/SPI 

      Siegert, T.; Diehl, R.; Vincent, A.~C.; Guglielmetti, F.; Krause, M.~G.~H.; Boehm, C. (2016-10-24)
      The positron annihilation gamma-ray signal in the Milky Way (MW) shows a puzzling morphology: a very bright bulge and a very low surface-brightness disk. A coherent explanation of the positron origin, propagation through ...

    • Soft X-ray absorption excess in gamma-ray burst afterglow spectra: Absorption by turbulent ISM 

      Tanga, M.; Schady, P.; Gatto, A.; Greiner, J.; Krause, M.~G.~H.; Diehl, R.; Savaglio, S.; Walch, S. (2016-11-01)
      Two-thirds of long duration gamma-ray bursts (GRBs) show soft X-ray absorption in excess of the Milky Way. The column densities of metals inferred from UV and optical spectra differ from those derived from soft X-ray ...

    • Squeezed between shells? On the origin of the Lupus I molecular cloud. - II. APEX CO and GASS HI observations 

      Gaczkowski, B.; Roccatagliata, V.; Flaischlen, S.; Kroell, D.; Krause, M.~G.~H.; Burkert, A.; Diehl, R.; Fierlinger, K.; Ngoumou, J.; Preibisch, T. (2017-12-12)
      Context. The Lupus I cloud is found between the Upper-Scorpius (USco) and the Upper-Centaurus-Lupus (UCL) sub-groups of the Scorpius-Centaurus OB-association, where the expanding USco H I shell appears to interact with a ...

    • Squeezed between shells? The origin of the Lupus I molecular cloud. APEX/LABOCA, Herschel, and Planck observations 

      Gaczkowski, B.; Preibisch, T.; Stanke, T.; Krause, M.~G.~H.; Burkert, A.; Diehl, R.; Fierlinger, K.; Kroell, D.; Ngoumou, J.; Roccatagliata, V. (2015-12-01)
      Context. The Lupus I cloud is found between the Upper Scorpius (USco) and the Upper Centaurus-Lupus (UCL) subgroups of the Scorpius-Centaurus OB association, where the expanding USco H I shell appears to interact with a ...

    • Stellar feedback efficiencies: supernovae versus stellar winds 

      Fierlinger, K.~M.; Burkert, A.; Ntormousi, E.; Fierlinger, P.; Schartmann, M.; Ballone, A.; Krause, M.~G.~H.; Diehl, R. (2016-02-11)
      Stellar winds and supernova (SN) explosions of massive stars (`stellar feedback') create bubbles in the interstellar medium (ISM) and insert newly produced heavy elements and kinetic energy into their surroundings, possibly ...