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FIRST radio counterpart candidates to ULXs: a catalogue

  • D. Pérez-Ramírez
  • J. R. Sánchez-Sutil
  • A. Muñoz-Arjonilla
  • J. Martí
  • J. L. Garrido
  • P. Luque-Escamilla
Conference paper

Abstract

Ultraluminous X-ray sources (ULXs) are the most luminous discrete X-ray sources (excluding AGNs) in the local Universe with observed luminosities above, and in many cases in excess of, 1039 erg s−1. Their physical nature is still uncertain, and many models have been proposed to explain their unusual luminosities. Some of them favour the possible nature of these objects as extragalactic microquasars with strong beaming effects. Others, instead, rely on accretion onto intermediate-mass black holes. In any case, both interpretations offer perspectives for possible gamma-ray detections by future space missions. In order to help to constrain at present the ULX physical nature, we provide here an account of our search for radio counterparts to ULXs located in nearby galaxies, based on a systematic cross-identification of the most recent, available and extensive ULX catalogues and radio archival data. Although we ended up with 70 positional coincidences, most of them were located within the nuclear regions of these galaxies, and thus, they do not represent true ULXs. However, among these sources we identify 11 remarkable cases not previously reported of ULX and radio emission coincidence. Future follow up of these promising cases with a multi-wavelength approach could be useful to improve our understanding of the ULX phenomenon.

Keywords

X-ray: galaxies X-ray: stars Radio continuum: galaxies Radio continuum: stars X-ray: binaries Black hole physics 

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References

  1. [Aharonian et al., 2005]
    Aharonian, F., et al.: Discovery of very high energy gamma rays associated with an X-ray binary. Science 309(5735), 746–749 (2005) ADSCrossRefGoogle Scholar
  2. [Albert et al., 2006]
    Albert, J., et al.: Variable very-high-energy gamma-ray emission from the microquasar LS I +61 303. Science 312(5781), 1771–1773 (2006) ADSCrossRefGoogle Scholar
  3. [Begelman, 2002]
    Begelman, M.C.: Super-eddington fluxes from thin accretion disks? Astrophys. J. 568, L97–L100 (2002) ADSCrossRefGoogle Scholar
  4. [Bertone et al., 2005]
    Bertone, G., Zentner, A.R., Silk, J.: New signature of dark matter annihilations: gamma rays from intermediate-mass black holes. Phys. Rev. D 72(10), 103517 (2005) ADSCrossRefGoogle Scholar
  5. [Colbert and Ptak, 2002]
    Colbert, E.J.M., Ptak, A.F.: A catalogue of candidate intermediate-luminosity X-ray objects. Astrophys. J. Suppl. Ser. 143, 25–45 (2002) ADSCrossRefGoogle Scholar
  6. [Georganopoulos et al., 2002]
    Georganopoulos, M., Aharonian, F.A., Kirk, J.G.: External Compton emission from relativistic jets in galactic black hole candidates and ultraluminous X-ray sources. Astron. Astrophys. 388, L25–L28 (2002) ADSCrossRefGoogle Scholar
  7. [Jenkins et al., 2004]
    Jenkins, L.P., Roberts, T.P., Warwick, R.S., et al.: An XMM-Newton view of M101—I. The luminous X-ray source population. Mon. Not. Roy. Astron. Soc. 349, 404–424 (2004) ADSCrossRefGoogle Scholar
  8. [King et al., 2001]
    King, A.R., Davies, M.B., Ward, M.J., Fabbiano, G., Elvis, M.: Ultraluminous X-ray sources in external galaxies. Astrophys. J. 552, L109–L112 (2001) ADSCrossRefGoogle Scholar
  9. [Liu and Bregman, 2005]
    Liu, J.-F., Bregman, J.N.: Ultraluminous X-ray sources in nearby galaxies from ROSAT high resolution imager observations I. Data Analysis. Astrophys. J. Suppl. Ser. 157, 59–125 (2005) ADSCrossRefGoogle Scholar
  10. [Liu and Mirabel, 2005]
    Liu, Q.Z., Mirabel, I.F.: A catalogue of ultraluminous X-ray sources in external galaxies. Astron. Astrophys. 429, 1125–1129 (2005) ADSCrossRefGoogle Scholar
  11. [Madhusudhan et al., 2006]
    Madhusudhan, N., Justham, S., Nelson, L., Paxton, B., et al.: Models of ultraluminous X-ray sources with intermediate-mass black holes. Astrophys. J. 640, 918–922 (2006) ADSCrossRefGoogle Scholar
  12. [Makishima et al., 2000]
    Makishima, K., Kubota, A., Mizuno, T., Ohnishi, T., et al.: The nature of ultraluminous compact X-ray sources in nearby spiral galaxies. Astrophys. J. 535, 632–643 (2000) ADSCrossRefGoogle Scholar
  13. [Sánchez-Sutil et al., 2006]
    Sánchez-Sutil, J.R., Muñoz-Arjonilla, A.J., Martí, J.: A catalogue of ultra-luminous X-ray source coincidences with FIRST radio sources. Astron. Astrophys. 452, 739–742 (2006) ADSCrossRefGoogle Scholar
  14. [White et al., 1997]
    White, R.L., Becker, R.H., Helfand, D.J., Gregg, M.D.: A catalogue of 1.4 GHz radio sources from the FIRST survey. Astrophys. J. 475, 479 (1997) ADSCrossRefGoogle Scholar

Copyright information

© Springer 2007

Authors and Affiliations

  • D. Pérez-Ramírez
    • 1
  • J. R. Sánchez-Sutil
    • 1
  • A. Muñoz-Arjonilla
    • 1
  • J. Martí
    • 1
  • J. L. Garrido
    • 1
  • P. Luque-Escamilla
    • 1
  1. 1.Departamento de FísicaUniversidad de JaénJaénSpain

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